* [PATCH v2] block: serialize elevator changes for the same queue using a writer lock
@ 2026-06-23 1:32 Shin'ichiro Kawasaki
2026-06-23 5:29 ` Nilay Shroff
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Shin'ichiro Kawasaki @ 2026-06-23 1:32 UTC (permalink / raw)
To: linux-block, Jens Axboe; +Cc: Ming Lei, Nilay Shroff, Shin'ichiro Kawasaki
When elevator_change() is called concurrently for the same queue, the
elevator_change_done() function runs concurrently as well. This function
adds or deletes kobjects for the debugfs entry of the queue. Then the
concurrent calls cause memory corruption of the kobjects and result in a
process hang. The core part of the elevator switch is protected by queue
freeze and q->elevator_lock. However, since the commit 559dc11143eb
("block: move elv_register[unregister]_queue out of elevator_lock"), the
elevator_change_done() is not serialized. Hence the memory corruption
and the hang.
The failures are observed when udev-worker writes to a sysfs
queue/scheduler attribute file while the blktests test case block/005
writes to the same attribute file. The failure also can be recreated by
running two processes that write to the same queue/scheduler file
concurrently. The failure is observed since another commit 370ac285f23a
("block: avoid cpu_hotplug_lock depedency on freeze_lock"). This commit
changed the behavior of queue freeze and it unveiled the failure.
Fix the failure by changing elv_iosched_store() to acquire
update_nr_hwq_lock as the writer lock instead of the reader lock. This
serializes the whole elevator switch steps, including the
elevator_change_done() call.
Fixes: 559dc11143eb ("block: move elv_register[unregister]_queue out of elevator_lock")
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
---
I observed that the blktests test case block/005 hung on a specific
server hardware using a specific HDD as a block device. During the test
case run, the kernel reported KASAN null-ptr-deref and slab-use-after-
free errors. The failure happened when a sysfs queue/scheduler attribute
file is written concurrently. I reported the failure and shared a
candidate fix patch as RFC [1]. Based on the comments and discussion on
the RFC patch, I propose this v2 patch that avoids introducing a new
lock. My thanks go to Ming and Nilay for the discussion.
Please refer to [1] for details of the failure. Also, I created a
blktests test case that recreates the hang [2], which I used to test the
fix.
* Changes from RFC v1
- Instead of adding a new mutex to struct request_queue, replace the
reader lock on update_nr_hwq_lock with the writer lock in
elv_iosched_store().
[1] https://lore.kernel.org/linux-block/20260611074200.474676-1-shinichiro.kawasaki@wdc.com/
[2] https://github.com/kawasaki/blktests/commit/8e80b3ccc0bbbe3f209d00eacd138d020de97fc6
block/elevator.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/block/elevator.c b/block/elevator.c
index 3bcd37c2aa34..b03185a217ff 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -813,7 +813,7 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf,
* update_nr_hwq_lock -> kn->active (via del_gendisk -> kobject_del)
* kn->active -> update_nr_hwq_lock (via this sysfs write path)
*/
- if (!down_read_trylock(&set->update_nr_hwq_lock)) {
+ if (!down_write_trylock(&set->update_nr_hwq_lock)) {
ret = -EBUSY;
goto out;
}
@@ -824,7 +824,7 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf,
} else {
ret = -ENOENT;
}
- up_read(&set->update_nr_hwq_lock);
+ up_write(&set->update_nr_hwq_lock);
out:
if (ctx.type)
--
2.54.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v2] block: serialize elevator changes for the same queue using a writer lock
2026-06-23 1:32 [PATCH v2] block: serialize elevator changes for the same queue using a writer lock Shin'ichiro Kawasaki
@ 2026-06-23 5:29 ` Nilay Shroff
2026-06-24 9:44 ` Ming Lei
2026-06-24 15:12 ` Ming Lei
2 siblings, 0 replies; 6+ messages in thread
From: Nilay Shroff @ 2026-06-23 5:29 UTC (permalink / raw)
To: Shin'ichiro Kawasaki, linux-block, Jens Axboe; +Cc: Ming Lei
On 6/23/26 7:02 AM, Shin'ichiro Kawasaki wrote:
> When elevator_change() is called concurrently for the same queue, the
> elevator_change_done() function runs concurrently as well. This function
> adds or deletes kobjects for the debugfs entry of the queue. Then the
> concurrent calls cause memory corruption of the kobjects and result in a
> process hang. The core part of the elevator switch is protected by queue
> freeze and q->elevator_lock. However, since the commit 559dc11143eb
> ("block: move elv_register[unregister]_queue out of elevator_lock"), the
> elevator_change_done() is not serialized. Hence the memory corruption
> and the hang.
>
> The failures are observed when udev-worker writes to a sysfs
> queue/scheduler attribute file while the blktests test case block/005
> writes to the same attribute file. The failure also can be recreated by
> running two processes that write to the same queue/scheduler file
> concurrently. The failure is observed since another commit 370ac285f23a
> ("block: avoid cpu_hotplug_lock depedency on freeze_lock"). This commit
> changed the behavior of queue freeze and it unveiled the failure.
>
> Fix the failure by changing elv_iosched_store() to acquire
> update_nr_hwq_lock as the writer lock instead of the reader lock. This
> serializes the whole elevator switch steps, including the
> elevator_change_done() call.
>
> Fixes: 559dc11143eb ("block: move elv_register[unregister]_queue out of elevator_lock")
> Signed-off-by: Shin'ichiro Kawasaki<shinichiro.kawasaki@wdc.com>
Looks good to me.
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] block: serialize elevator changes for the same queue using a writer lock
2026-06-23 1:32 [PATCH v2] block: serialize elevator changes for the same queue using a writer lock Shin'ichiro Kawasaki
2026-06-23 5:29 ` Nilay Shroff
@ 2026-06-24 9:44 ` Ming Lei
2026-06-24 11:48 ` Shin'ichiro Kawasaki
2026-06-24 15:12 ` Ming Lei
2 siblings, 1 reply; 6+ messages in thread
From: Ming Lei @ 2026-06-24 9:44 UTC (permalink / raw)
To: Shin'ichiro Kawasaki; +Cc: linux-block, Jens Axboe, Nilay Shroff
On Tue, Jun 23, 2026 at 10:32:38AM +0900, Shin'ichiro Kawasaki wrote:
> When elevator_change() is called concurrently for the same queue, the
> elevator_change_done() function runs concurrently as well. This function
> adds or deletes kobjects for the debugfs entry of the queue. Then the
> concurrent calls cause memory corruption of the kobjects and result in a
> process hang. The core part of the elevator switch is protected by queue
> freeze and q->elevator_lock. However, since the commit 559dc11143eb
> ("block: move elv_register[unregister]_queue out of elevator_lock"), the
> elevator_change_done() is not serialized. Hence the memory corruption
> and the hang.
>
> The failures are observed when udev-worker writes to a sysfs
> queue/scheduler attribute file while the blktests test case block/005
> writes to the same attribute file. The failure also can be recreated by
> running two processes that write to the same queue/scheduler file
> concurrently. The failure is observed since another commit 370ac285f23a
> ("block: avoid cpu_hotplug_lock depedency on freeze_lock"). This commit
> changed the behavior of queue freeze and it unveiled the failure.
>
> Fix the failure by changing elv_iosched_store() to acquire
> update_nr_hwq_lock as the writer lock instead of the reader lock. This
> serializes the whole elevator switch steps, including the
> elevator_change_done() call.
>
> Fixes: 559dc11143eb ("block: move elv_register[unregister]_queue out of elevator_lock")
> Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
> ---
> I observed that the blktests test case block/005 hung on a specific
> server hardware using a specific HDD as a block device. During the test
> case run, the kernel reported KASAN null-ptr-deref and slab-use-after-
> free errors. The failure happened when a sysfs queue/scheduler attribute
> file is written concurrently. I reported the failure and shared a
> candidate fix patch as RFC [1]. Based on the comments and discussion on
> the RFC patch, I propose this v2 patch that avoids introducing a new
> lock. My thanks go to Ming and Nilay for the discussion.
>
> Please refer to [1] for details of the failure. Also, I created a
> blktests test case that recreates the hang [2], which I used to test the
> fix.
>
> * Changes from RFC v1
> - Instead of adding a new mutex to struct request_queue, replace the
> reader lock on update_nr_hwq_lock with the writer lock in
> elv_iosched_store().
>
> [1] https://lore.kernel.org/linux-block/20260611074200.474676-1-shinichiro.kawasaki@wdc.com/
> [2] https://github.com/kawasaki/blktests/commit/8e80b3ccc0bbbe3f209d00eacd138d020de97fc6
>
> block/elevator.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/block/elevator.c b/block/elevator.c
> index 3bcd37c2aa34..b03185a217ff 100644
> --- a/block/elevator.c
> +++ b/block/elevator.c
> @@ -813,7 +813,7 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf,
> * update_nr_hwq_lock -> kn->active (via del_gendisk -> kobject_del)
> * kn->active -> update_nr_hwq_lock (via this sysfs write path)
> */
> - if (!down_read_trylock(&set->update_nr_hwq_lock)) {
> + if (!down_write_trylock(&set->update_nr_hwq_lock)) {
> ret = -EBUSY;
> goto out;
> }
> @@ -824,7 +824,7 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf,
> } else {
> ret = -ENOENT;
> }
> - up_read(&set->update_nr_hwq_lock);
> + up_write(&set->update_nr_hwq_lock);
I feel this is still abuse of the above lock, which serves writer vs
reader wrt. updating hw queue.
How about the following fix?
diff --git a/block/elevator.c b/block/elevator.c
index 3bcd37c2aa34..0375eb77646e 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -627,8 +627,10 @@ static void elv_exit_and_release(struct elv_change_ctx *ctx,
static int elevator_change_done(struct request_queue *q,
struct elv_change_ctx *ctx)
{
+ bool exit_and_release = false;
int ret = 0;
+ mutex_lock(&q->elevator_lock);
if (ctx->old) {
struct elevator_resources res = {
.et = ctx->old->et,
@@ -640,10 +642,24 @@ static int elevator_change_done(struct request_queue *q,
kobject_put(&ctx->old->kobj);
}
if (ctx->new) {
+ if (ctx->new != q->elevator) {
+ ret = -EBUSY;
+ goto unlock;
+ }
ret = elv_register_queue(q, ctx->new, !ctx->no_uevent);
+ /*
+ * Tear down the failed elevator after dropping elevator_lock:
+ * elv_exit_and_release() freezes the queue and re-acquires
+ * elevator_lock itself, so it must not be called nested here.
+ */
if (ret)
- elv_exit_and_release(ctx, q);
+ exit_and_release = true;
}
+unlock:
+ mutex_unlock(&q->elevator_lock);
+
+ if (exit_and_release)
+ elv_exit_and_release(ctx, q);
return ret;
}
Thanks,
Ming
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v2] block: serialize elevator changes for the same queue using a writer lock
2026-06-24 9:44 ` Ming Lei
@ 2026-06-24 11:48 ` Shin'ichiro Kawasaki
2026-06-24 15:09 ` Ming Lei
0 siblings, 1 reply; 6+ messages in thread
From: Shin'ichiro Kawasaki @ 2026-06-24 11:48 UTC (permalink / raw)
To: Ming Lei; +Cc: linux-block, Jens Axboe, Nilay Shroff
On Jun 24, 2026 / 04:44, Ming Lei wrote:
> On Tue, Jun 23, 2026 at 10:32:38AM +0900, Shin'ichiro Kawasaki wrote:
[...]
> > Please refer to [1] for details of the failure. Also, I created a
> > blktests test case that recreates the hang [2], which I used to test the
> > fix.
> >
> > * Changes from RFC v1
> > - Instead of adding a new mutex to struct request_queue, replace the
> > reader lock on update_nr_hwq_lock with the writer lock in
> > elv_iosched_store().
> >
> > [1] https://lore.kernel.org/linux-block/20260611074200.474676-1-shinichiro.kawasaki@wdc.com/
> > [2] https://github.com/kawasaki/blktests/commit/8e80b3ccc0bbbe3f209d00eacd138d020de97fc6
> >
> > block/elevator.c | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
[...]
> I feel this is still abuse of the above lock, which serves writer vs
> reader wrt. updating hw queue.
>
> How about the following fix?
(snip)
Thank you for the idea. I applied the suggested fix on top of the v7.1 kernel,
and ran the test case that does the concurrent write to the sysfs sched file
[2]. Unfortunately, the test case hung. Before the hang, the kernel reported
WARNs in sysfs_create_dir_ns() [3]. KASAN slab-use-after-free was observed also.
I also noticed that another WARN was observed during boot [4].
[3]
[ 75.184223] [ T1820] run blktests block/044 at 2026-06-24 20:37:20
[ 75.229561] [ T1830] null_blk: disk nullb0 created
[ 75.234717] [ T1830] null_blk: module loaded
[ 75.249186] [ T1820] null_blk: disk nullb1 created
[ 88.092222] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 88.102051] [ T1842] CPU: 6 UID: 0 PID: 1842 Comm: check Tainted: G W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 88.102067] [ T1842] Tainted: [W]=WARN
[ 88.102070] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 88.102075] [ T1842] Call Trace:
[ 88.102080] [ T1842] <TASK>
[ 88.102084] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 88.102105] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 88.102117] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 88.102132] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 88.102146] [ T1842] ? kfree+0x1d6/0x620
[ 88.102156] [ T1842] kobject_add_internal+0x26f/0x800
[ 88.102171] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 88.102180] [ T1842] kobject_add+0x139/0x1a0
[ 88.102190] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 88.102199] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 88.102208] [ T1842] ? kasan_quarantine_put+0xf5/0x240
[ 88.102218] [ T1842] ? kfree+0x21c/0x620
[ 88.102228] [ T1842] ? trace_hardirqs_on+0x53/0x1a0
[ 88.102237] [ T1842] elevator_change_done+0x26f/0x690
[ 88.102250] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 88.102259] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 88.102274] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 88.102285] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 88.102293] [ T1842] elevator_change+0x283/0x4f0
[ 88.102305] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 88.102314] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 88.102326] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 88.102335] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 88.102351] [ T1842] ? lock_acquire+0x126/0x140
[ 88.102364] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 88.102373] [ T1842] queue_attr_store+0x23f/0x360
[ 88.102382] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 88.102393] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 88.102401] [ T1842] ? lock_release+0xfa/0x120
[ 88.102412] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 88.102442] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 88.102452] [ T1842] ? lock_acquire+0x126/0x140
[ 88.102462] [ T1842] ? lock_acquire+0x126/0x140
[ 88.102473] [ T1842] ? lock_release+0xfa/0x120
[ 88.102483] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 88.102492] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 88.102503] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 88.102511] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 88.102522] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 88.102530] [ T1842] vfs_write+0x524/0x1010
[ 88.102541] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 88.102548] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 88.102558] [ T1842] ? wp_page_reuse+0x160/0x1e0
[ 88.102574] [ T1842] ? handle_pte_fault+0x54e/0x760
[ 88.102586] [ T1842] ksys_write+0xff/0x200
[ 88.102595] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 88.102607] [ T1842] do_syscall_64+0xf4/0x660
[ 88.102620] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 88.102637] [ T1842] ? count_memcg_events+0x37f/0x480
[ 88.102651] [ T1842] ? lock_release+0xfa/0x120
[ 88.102662] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 88.102670] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 88.102680] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 88.102693] [ T1842] ? lock_release+0xfa/0x120
[ 88.102703] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 88.102713] [ T1842] ? irqentry_exit+0xb0/0x810
[ 88.102720] [ T1842] ? do_syscall_64+0x34/0x660
[ 88.102730] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 88.102737] [ T1842] ? irqentry_exit+0xb5/0x810
[ 88.102743] [ T1842] ? do_syscall_64+0xab/0x660
[ 88.102754] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 88.102762] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 88.102772] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 88.102779] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 88.102789] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 88.102800] [ T1842] RDX: 0000000000000004 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 88.102809] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 88.102818] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004
[ 88.102827] [ T1842] R13: 0000000000000004 R14: 0000562ec532aa50 R15: 0000562ec5397300
[ 88.102854] [ T1842] </TASK>
[ 88.536717] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 90.116333] [ T1841] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 90.127915] [ T1841] CPU: 0 UID: 0 PID: 1841 Comm: check Tainted: G W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 90.127935] [ T1841] Tainted: [W]=WARN
[ 90.127937] [ T1841] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 90.127941] [ T1841] Call Trace:
[ 90.127945] [ T1841] <TASK>
[ 90.127952] [ T1841] dump_stack_lvl+0x6e/0xa0
[ 90.127971] [ T1841] sysfs_warn_dup.cold+0x17/0x24
[ 90.127982] [ T1841] sysfs_create_dir_ns+0x1fc/0x270
[ 90.128000] [ T1841] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 90.128010] [ T1841] ? kfree+0x1d6/0x620
[ 90.128024] [ T1841] kobject_add_internal+0x26f/0x800
[ 90.128032] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.128039] [ T1841] kobject_add+0x139/0x1a0
[ 90.128044] [ T1841] ? trace_hardirqs_on+0x19/0x1a0
[ 90.128048] [ T1841] ? __pfx_kobject_add+0x10/0x10
[ 90.128053] [ T1841] ? kasan_quarantine_put+0xf5/0x240
[ 90.128058] [ T1841] ? kfree+0x21c/0x620
[ 90.128063] [ T1841] ? trace_hardirqs_on+0x53/0x1a0
[ 90.128066] [ T1841] elevator_change_done+0x26f/0x690
[ 90.128074] [ T1841] ? __pfx_elevator_change_done+0x10/0x10
[ 90.128078] [ T1841] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 90.128086] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.128091] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.128095] [ T1841] elevator_change+0x283/0x4f0
[ 90.128103] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.128107] [ T1841] elv_iosched_store+0x30c/0x3a0
[ 90.128112] [ T1841] ? __pfx_elv_iosched_store+0x10/0x10
[ 90.128116] [ T1841] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 90.128131] [ T1841] ? lock_acquire+0x126/0x140
[ 90.128138] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.128142] [ T1841] queue_attr_store+0x23f/0x360
[ 90.128150] [ T1841] ? __mutex_lock+0x1536/0x25a0
[ 90.128155] [ T1841] ? __pfx_queue_attr_store+0x10/0x10
[ 90.128159] [ T1841] ? lock_release+0xfa/0x120
[ 90.128164] [ T1841] ? __pfx___mutex_lock+0x10/0x10
[ 90.128169] [ T1841] ? __pfx__copy_from_iter+0x10/0x10
[ 90.128175] [ T1841] ? lock_acquire+0x126/0x140
[ 90.128179] [ T1841] ? lock_acquire+0x126/0x140
[ 90.128184] [ T1841] ? lock_release+0xfa/0x120
[ 90.128192] [ T1841] ? sysfs_file_kobj+0xb9/0x1b0
[ 90.128196] [ T1841] ? sysfs_kf_write+0x65/0x170
[ 90.128201] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.128205] [ T1841] kernfs_fop_write_iter+0x3da/0x5e0
[ 90.128214] [ T1841] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 90.128218] [ T1841] vfs_write+0x524/0x1010
[ 90.128223] [ T1841] ? __pfx_vfs_write+0x10/0x10
[ 90.128229] [ T1841] ? __pfx_do_raw_spin_lock+0x10/0x10
[ 90.128238] [ T1841] ? __pfx_pte_val+0x10/0x10
[ 90.128244] [ T1841] ksys_write+0xff/0x200
[ 90.128248] [ T1841] ? __pfx_ksys_write+0x10/0x10
[ 90.128252] [ T1841] ? lock_release+0xfa/0x120
[ 90.128257] [ T1841] ? rcu_read_unlock+0x1c/0x60
[ 90.128260] [ T1841] ? wp_page_reuse+0x160/0x1e0
[ 90.128265] [ T1841] do_syscall_64+0xf4/0x660
[ 90.128277] [ T1841] ? handle_pte_fault+0x54e/0x760
[ 90.128283] [ T1841] ? __pfx_handle_pte_fault+0x10/0x10
[ 90.128288] [ T1841] ? __pfx_pmd_val+0x10/0x10
[ 90.128293] [ T1841] ? __handle_mm_fault+0xa02/0xef0
[ 90.128302] [ T1841] ? do_raw_spin_unlock+0x59/0x230
[ 90.128306] [ T1841] ? __pfx___css_rstat_updated+0x10/0x10
[ 90.128315] [ T1841] ? count_memcg_events+0x37f/0x480
[ 90.128328] [ T1841] ? lock_release+0xfa/0x120
[ 90.128332] [ T1841] ? rcu_read_unlock+0x1c/0x60
[ 90.128336] [ T1841] ? handle_mm_fault+0x4d1/0x7d0
[ 90.128341] [ T1841] ? do_user_addr_fault+0x15d/0xed0
[ 90.128347] [ T1841] ? lock_release+0xfa/0x120
[ 90.128351] [ T1841] ? do_user_addr_fault+0x811/0xed0
[ 90.128356] [ T1841] ? irqentry_exit+0xb0/0x810
[ 90.128359] [ T1841] ? do_syscall_64+0x34/0x660
[ 90.128367] [ T1841] ? trace_hardirqs_on+0x19/0x1a0
[ 90.128370] [ T1841] ? irqentry_exit+0xb5/0x810
[ 90.128373] [ T1841] ? do_syscall_64+0xab/0x660
[ 90.128378] [ T1841] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 90.128388] [ T1841] RIP: 0033:0x7f96f4878bbe
[ 90.128393] [ T1841] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 90.128396] [ T1841] RSP: 002b:00007ffcb76eba90 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 90.128402] [ T1841] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 90.128405] [ T1841] RDX: 000000000000000c RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 90.128410] [ T1841] RBP: 00007ffcb76ebaa0 R08: 0000000000000000 R09: 0000000000000000
[ 90.128413] [ T1841] R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000c
[ 90.128415] [ T1841] R13: 000000000000000c R14: 0000562ec532aa50 R15: 0000562ec5397e70
[ 90.128421] [ T1841] </TASK>
[ 90.128435] [ T1841] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 90.638084] [ T1841] ==================================================================
[ 90.646403] [ T1841] BUG: KASAN: slab-use-after-free in blk_mq_free_sched_tags+0x124/0x160
[ 90.654950] [ T1841] Read of size 4 at addr ffff88818265ad40 by task check/1841
[ 90.665102] [ T1841] CPU: 4 UID: 0 PID: 1841 Comm: check Tainted: G W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 90.665108] [ T1841] Tainted: [W]=WARN
[ 90.665109] [ T1841] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 90.665111] [ T1841] Call Trace:
[ 90.665113] [ T1841] <TASK>
[ 90.665115] [ T1841] dump_stack_lvl+0x6e/0xa0
[ 90.665123] [ T1841] print_address_description.constprop.0+0x70/0x300
[ 90.665129] [ T1841] ? blk_mq_free_sched_tags+0x124/0x160
[ 90.665132] [ T1841] print_report+0xfc/0x1ff
[ 90.665136] [ T1841] ? __virt_addr_valid+0x1d1/0x3f0
[ 90.665141] [ T1841] ? blk_mq_free_sched_tags+0x124/0x160
[ 90.665143] [ T1841] kasan_report+0xf6/0x1c0
[ 90.665148] [ T1841] ? blk_mq_free_sched_tags+0x124/0x160
[ 90.665152] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.665157] [ T1841] blk_mq_free_sched_tags+0x124/0x160
[ 90.665160] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.665163] [ T1841] blk_mq_free_sched_res+0x50/0x170
[ 90.665167] [ T1841] elevator_change_done+0x4f6/0x690
[ 90.665172] [ T1841] ? __pfx_elevator_change_done+0x10/0x10
[ 90.665175] [ T1841] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 90.665181] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.665185] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.665188] [ T1841] elevator_change+0x283/0x4f0
[ 90.665192] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.665196] [ T1841] elv_iosched_store+0x30c/0x3a0
[ 90.665200] [ T1841] ? __pfx_elv_iosched_store+0x10/0x10
[ 90.665204] [ T1841] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 90.665209] [ T1841] ? lock_acquire+0x126/0x140
[ 90.665215] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.665218] [ T1841] queue_attr_store+0x23f/0x360
[ 90.665222] [ T1841] ? __mutex_lock+0x1536/0x25a0
[ 90.665226] [ T1841] ? __pfx_queue_attr_store+0x10/0x10
[ 90.665229] [ T1841] ? lock_release+0xfa/0x120
[ 90.665233] [ T1841] ? __pfx___mutex_lock+0x10/0x10
[ 90.665237] [ T1841] ? __pfx__copy_from_iter+0x10/0x10
[ 90.665241] [ T1841] ? lock_acquire+0x126/0x140
[ 90.665244] [ T1841] ? lock_acquire+0x126/0x140
[ 90.665248] [ T1841] ? lock_release+0xfa/0x120
[ 90.665252] [ T1841] ? sysfs_file_kobj+0xb9/0x1b0
[ 90.665255] [ T1841] ? sysfs_kf_write+0x65/0x170
[ 90.665259] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 90.665262] [ T1841] kernfs_fop_write_iter+0x3da/0x5e0
[ 90.665266] [ T1841] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 90.665268] [ T1841] vfs_write+0x524/0x1010
[ 90.665273] [ T1841] ? __pfx_vfs_write+0x10/0x10
[ 90.665278] [ T1841] ? __pfx_do_raw_spin_lock+0x10/0x10
[ 90.665281] [ T1841] ? __pfx_pte_val+0x10/0x10
[ 90.665286] [ T1841] ksys_write+0xff/0x200
[ 90.665289] [ T1841] ? __pfx_ksys_write+0x10/0x10
[ 90.665292] [ T1841] ? lock_release+0xfa/0x120
[ 90.665295] [ T1841] ? rcu_read_unlock+0x1c/0x60
[ 90.665298] [ T1841] ? wp_page_reuse+0x160/0x1e0
[ 90.665302] [ T1841] do_syscall_64+0xf4/0x660
[ 90.665308] [ T1841] ? handle_pte_fault+0x54e/0x760
[ 90.665312] [ T1841] ? __pfx_handle_pte_fault+0x10/0x10
[ 90.665316] [ T1841] ? __pfx_pmd_val+0x10/0x10
[ 90.665320] [ T1841] ? __handle_mm_fault+0xa02/0xef0
[ 90.665324] [ T1841] ? do_raw_spin_unlock+0x59/0x230
[ 90.665327] [ T1841] ? __pfx___css_rstat_updated+0x10/0x10
[ 90.665334] [ T1841] ? count_memcg_events+0x37f/0x480
[ 90.665339] [ T1841] ? lock_release+0xfa/0x120
[ 90.665343] [ T1841] ? rcu_read_unlock+0x1c/0x60
[ 90.665345] [ T1841] ? handle_mm_fault+0x4d1/0x7d0
[ 90.665349] [ T1841] ? do_user_addr_fault+0x15d/0xed0
[ 90.665353] [ T1841] ? lock_release+0xfa/0x120
[ 90.665357] [ T1841] ? do_user_addr_fault+0x811/0xed0
[ 90.665360] [ T1841] ? irqentry_exit+0xb0/0x810
[ 90.665363] [ T1841] ? do_syscall_64+0x34/0x660
[ 90.665366] [ T1841] ? trace_hardirqs_on+0x19/0x1a0
[ 90.665369] [ T1841] ? irqentry_exit+0xb5/0x810
[ 90.665372] [ T1841] ? do_syscall_64+0xab/0x660
[ 90.665375] [ T1841] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 90.665378] [ T1841] RIP: 0033:0x7f96f4878bbe
[ 90.665383] [ T1841] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 90.665385] [ T1841] RSP: 002b:00007ffcb76eba90 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 90.665390] [ T1841] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 90.665392] [ T1841] RDX: 000000000000000c RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 90.665394] [ T1841] RBP: 00007ffcb76ebaa0 R08: 0000000000000000 R09: 0000000000000000
[ 90.665396] [ T1841] R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000c
[ 90.665397] [ T1841] R13: 000000000000000c R14: 0000562ec532aa50 R15: 0000562ec5397e70
[ 90.665402] [ T1841] </TASK>
[ 91.124911] [ T1841] Allocated by task 1841:
[ 91.129401] [ T1841] kasan_save_stack+0x30/0x50
[ 91.134237] [ T1841] kasan_save_track+0x14/0x30
[ 91.139072] [ T1841] __kasan_kmalloc+0x9a/0xb0
[ 91.143822] [ T1841] __kmalloc_noprof+0x2bb/0x820
[ 91.148832] [ T1841] blk_mq_alloc_sched_tags+0x72/0x2f0
[ 91.154364] [ T1841] blk_mq_alloc_sched_res+0x86/0x220
[ 91.159802] [ T1841] elevator_change+0x113/0x4f0
[ 91.164725] [ T1841] elv_iosched_store+0x30c/0x3a0
[ 91.169821] [ T1841] queue_attr_store+0x23f/0x360
[ 91.174832] [ T1841] kernfs_fop_write_iter+0x3da/0x5e0
[ 91.180276] [ T1841] vfs_write+0x524/0x1010
[ 91.184765] [ T1841] ksys_write+0xff/0x200
[ 91.189168] [ T1841] do_syscall_64+0xf4/0x660
[ 91.193833] [ T1841] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 91.202386] [ T1841] Freed by task 1842:
[ 91.206535] [ T1841] kasan_save_stack+0x30/0x50
[ 91.211380] [ T1841] kasan_save_track+0x14/0x30
[ 91.216222] [ T1841] kasan_save_free_info+0x3b/0x70
[ 91.221414] [ T1841] __kasan_slab_free+0x6b/0x90
[ 91.226346] [ T1841] kfree+0x21c/0x620
[ 91.230409] [ T1841] blk_mq_free_sched_res+0x50/0x170
[ 91.235777] [ T1841] elevator_change_done+0x17f/0x690
[ 91.241141] [ T1841] elevator_change+0x283/0x4f0
[ 91.246069] [ T1841] elv_iosched_store+0x30c/0x3a0
[ 91.251174] [ T1841] queue_attr_store+0x23f/0x360
[ 91.256195] [ T1841] kernfs_fop_write_iter+0x3da/0x5e0
[ 91.261647] [ T1841] vfs_write+0x524/0x1010
[ 91.266146] [ T1841] ksys_write+0xff/0x200
[ 91.270556] [ T1841] do_syscall_64+0xf4/0x660
[ 91.275227] [ T1841] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 91.283792] [ T1841] The buggy address belongs to the object at ffff88818265ad40
which belongs to the cache kmalloc-rnd-04-32 of size 32
[ 91.298776] [ T1841] The buggy address is located 0 bytes inside of
freed 32-byte region [ffff88818265ad40, ffff88818265ad60)
[ 91.315327] [ T1841] The buggy address belongs to the physical page:
[ 91.321911] [ T1841] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x18265a
[ 91.330919] [ T1841] flags: 0x17ffffc0000000(node=0|zone=2|lastcpupid=0x1fffff)
[ 91.338457] [ T1841] page_type: f5(slab)
[ 91.342604] [ T1841] raw: 0017ffffc0000000 ffff88810004ca00 dead000000000100 dead000000000122
[ 91.351361] [ T1841] raw: 0000000000000000 0000000800400040 00000000f5000000 0000000000000000
[ 91.360116] [ T1841] page dumped because: kasan: bad access detected
[ 91.369218] [ T1841] Memory state around the buggy address:
[ 91.375028] [ T1841] ffff88818265ac00: fa fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
[ 91.383280] [ T1841] ffff88818265ac80: fc fc fc fc fc fc fc fc fa fb fb fb fc fc fc fc
[ 91.391530] [ T1841] >ffff88818265ad00: fc fc fc fc fc fc fc fc fa fb fb fb fc fc fc fc
[ 91.399782] [ T1841] ^
[ 91.406132] [ T1841] ffff88818265ad80: fc fc fc fc fc fc fc fc fa fb fb fb fc fc fc fc
[ 91.414400] [ T1841] ffff88818265ae00: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
[ 91.422666] [ T1841] ==================================================================
[ 91.431032] [ T1841] Oops: general protection fault, probably for non-canonical address 0xe066fc31c00000fa: 0000 [#1] SMP KASAN PTI
[ 91.449248] [ T1841] KASAN: maybe wild-memory-access in range [0x0338018e000007d0-0x0338018e000007d7]
[ 91.458755] [ T1841] CPU: 0 UID: 0 PID: 1841 Comm: check Tainted: G B W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 91.469576] [ T1841] Tainted: [B]=BAD_PAGE, [W]=WARN
[ 91.474834] [ T1841] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 91.483316] [ T1841] RIP: 0010:blk_mq_free_rqs+0x38/0x790
[ 91.489034] [ T1841] Code: 00 00 fc ff df 41 57 49 89 f7 48 81 c6 a0 00 00 00 41 56 49 89 fe 41 55 41 54 55 53 48 83 ec 48 89 14 24 48 89 f2 48 c1 ea 03 <80> 3c 02 00 0f 85 fa 05 00 00 49 8b 87 a0 00 00 00 48 39 c6 0f 84
[ 91.509311] [ T1841] RSP: 0018:ffff88815455f530 EFLAGS: 00010206
[ 91.515656] [ T1841] RAX: dffffc0000000000 RBX: 0338018e00000732 RCX: 0000000000000000
[ 91.523920] [ T1841] RDX: 00670031c00000fa RSI: 0338018e000007d2 RDI: ffff888148d6f838
[ 91.532185] [ T1841] RBP: ffff888148d6f838 R08: ffffffffa7baa33a R09: fffffbfff5c10688
[ 91.540452] [ T1841] R10: fffffbfff5c10689 R11: 0000000000000001 R12: ffff88818265ad40
[ 91.548727] [ T1841] R13: ffff888148d6f838 R14: ffff888148d6f838 R15: 0338018e00000732
[ 91.557009] [ T1841] FS: 00007f96f4807780(0000) GS:ffff8887afe48000(0000) knlGS:0000000000000000
[ 91.566248] [ T1841] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 91.573153] [ T1841] CR2: 0000562ec532aa51 CR3: 0000000144fee001 CR4: 00000000001726f0
[ 91.581447] [ T1841] Call Trace:
[ 91.585060] [ T1841] <TASK>
[ 91.588325] [ T1841] blk_mq_free_map_and_rqs+0x23/0x130
[ 91.594029] [ T1841] blk_mq_free_sched_tags+0xbd/0x160
[ 91.599636] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 91.605159] [ T1841] blk_mq_free_sched_res+0x50/0x170
[ 91.610681] [ T1841] elevator_change_done+0x4f6/0x690
[ 91.616204] [ T1841] ? __pfx_elevator_change_done+0x10/0x10
[ 91.622245] [ T1841] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 91.628363] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 91.633880] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 91.639384] [ T1841] elevator_change+0x283/0x4f0
[ 91.644453] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 91.649987] [ T1841] elv_iosched_store+0x30c/0x3a0
[ 91.655224] [ T1841] ? __pfx_elv_iosched_store+0x10/0x10
[ 91.660981] [ T1841] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 91.667337] [ T1841] ? lock_acquire+0x126/0x140
[ 91.672301] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 91.677778] [ T1841] queue_attr_store+0x23f/0x360
[ 91.682911] [ T1841] ? __mutex_lock+0x1536/0x25a0
[ 91.688037] [ T1841] ? __pfx_queue_attr_store+0x10/0x10
[ 91.693674] [ T1841] ? lock_release+0xfa/0x120
[ 91.698532] [ T1841] ? __pfx___mutex_lock+0x10/0x10
[ 91.703815] [ T1841] ? __pfx__copy_from_iter+0x10/0x10
[ 91.709362] [ T1841] ? lock_acquire+0x126/0x140
[ 91.714306] [ T1841] ? lock_acquire+0x126/0x140
[ 91.719248] [ T1841] ? lock_release+0xfa/0x120
[ 91.724094] [ T1841] ? sysfs_file_kobj+0xb9/0x1b0
[ 91.729198] [ T1841] ? sysfs_kf_write+0x65/0x170
[ 91.734214] [ T1841] ? __pfx_sysfs_kf_write+0x10/0x10
[ 91.739640] [ T1841] kernfs_fop_write_iter+0x3da/0x5e0
[ 91.745162] [ T1841] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 91.751187] [ T1841] vfs_write+0x524/0x1010
[ 91.755728] [ T1841] ? __pfx_vfs_write+0x10/0x10
[ 91.760694] [ T1841] ? __pfx_do_raw_spin_lock+0x10/0x10
[ 91.766260] [ T1841] ? __pfx_pte_val+0x10/0x10
[ 91.771042] [ T1841] ksys_write+0xff/0x200
[ 91.775465] [ T1841] ? __pfx_ksys_write+0x10/0x10
[ 91.780477] [ T1841] ? lock_release+0xfa/0x120
[ 91.785218] [ T1841] ? rcu_read_unlock+0x1c/0x60
[ 91.790134] [ T1841] ? wp_page_reuse+0x160/0x1e0
[ 91.795053] [ T1841] do_syscall_64+0xf4/0x660
[ 91.799701] [ T1841] ? handle_pte_fault+0x54e/0x760
[ 91.804864] [ T1841] ? __pfx_handle_pte_fault+0x10/0x10
[ 91.810371] [ T1841] ? __pfx_pmd_val+0x10/0x10
[ 91.815090] [ T1841] ? __handle_mm_fault+0xa02/0xef0
[ 91.820327] [ T1841] ? do_raw_spin_unlock+0x59/0x230
[ 91.825555] [ T1841] ? __pfx___css_rstat_updated+0x10/0x10
[ 91.831307] [ T1841] ? count_memcg_events+0x37f/0x480
[ 91.836623] [ T1841] ? lock_release+0xfa/0x120
[ 91.841334] [ T1841] ? rcu_read_unlock+0x1c/0x60
[ 91.846214] [ T1841] ? handle_mm_fault+0x4d1/0x7d0
[ 91.851268] [ T1841] ? do_user_addr_fault+0x15d/0xed0
[ 91.856588] [ T1841] ? lock_release+0xfa/0x120
[ 91.861293] [ T1841] ? do_user_addr_fault+0x811/0xed0
[ 91.866606] [ T1841] ? irqentry_exit+0xb0/0x810
[ 91.871396] [ T1841] ? do_syscall_64+0x34/0x660
[ 91.876188] [ T1841] ? trace_hardirqs_on+0x19/0x1a0
[ 91.881331] [ T1841] ? irqentry_exit+0xb5/0x810
[ 91.886129] [ T1841] ? do_syscall_64+0xab/0x660
[ 91.890926] [ T1841] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 91.896937] [ T1841] RIP: 0033:0x7f96f4878bbe
[ 91.901471] [ T1841] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 91.921483] [ T1841] RSP: 002b:00007ffcb76eba90 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 91.930047] [ T1841] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 91.938176] [ T1841] RDX: 000000000000000c RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 91.946306] [ T1841] RBP: 00007ffcb76ebaa0 R08: 0000000000000000 R09: 0000000000000000
[ 91.954436] [ T1841] R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000c
[ 91.962567] [ T1841] R13: 000000000000000c R14: 0000562ec532aa50 R15: 0000562ec5397e70
[ 91.970702] [ T1841] </TASK>
[ 91.973886] [ T1841] Modules linked in: null_blk nft_masq nft_reject_ipv4 act_csum cls_u32 sch_htb nf_nat_tftp nf_conntrack_tftp bridge stp llc target_core_user target_core_mod rfkill nf_conntrack_netbios_ns nf_conntrack_broadcast nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat ip6table_nat ip6table_mangle ip6table_raw ip6table_security iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_mangle iptable_raw iptable_security nf_tables ip6table_filter ip6_tables iptable_filter ip_tables qrtr intel_rapl_msr intel_rapl_common sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel iTCO_wdt intel_pmc_bxt kvm irqbypass rapl sunrpc intel_cstate intel_uncore pcspkr i2c_i801 i2c_smbus igb mei_me lpc_ich mei ioatdma dca wmi binfmt_misc joydev acpi_pad acpi_power_meter btrfs raid6_pq xor ses enclosure loop dm_multipath nfnetlink zram lz4hc_compress lz4_compress zstd_compress ast drm_client_lib i2c_algo_bit drm_shmem_helper
[ 91.974026] [ T1841] drm_kms_helper drm mpt3sas mpi3mr raid_class scsi_transport_sas scsi_dh_rdac scsi_dh_emc scsi_dh_alua i2c_dev fuse
[ 92.080026] [ T1841] ---[ end trace 0000000000000000 ]---
[ 92.106503] [ T1841] pstore: backend (erst) writing error (-28)
[ 92.112860] [ T1841] RIP: 0010:blk_mq_free_rqs+0x38/0x790
[ 92.118708] [ T1841] Code: 00 00 fc ff df 41 57 49 89 f7 48 81 c6 a0 00 00 00 41 56 49 89 fe 41 55 41 54 55 53 48 83 ec 48 89 14 24 48 89 f2 48 c1 ea 03 <80> 3c 02 00 0f 85 fa 05 00 00 49 8b 87 a0 00 00 00 48 39 c6 0f 84
[ 92.139931] [ T1841] RSP: 0018:ffff88815455f530 EFLAGS: 00010206
[ 92.140007] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 92.145981] [ T1841] RAX: dffffc0000000000 RBX: 0338018e00000732 RCX: 0000000000000000
[ 92.155553] [ T1842] CPU: 0 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 92.155560] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 92.155561] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 92.155563] [ T1842] Call Trace:
[ 92.155564] [ T1842] <TASK>
[ 92.155566] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 92.155624] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 92.155644] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 92.155652] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 92.155666] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 92.155672] [ T1842] ? kfree+0x1d6/0x620
[ 92.155682] [ T1842] kobject_add_internal+0x26f/0x800
[ 92.155690] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 92.155693] [ T1842] kobject_add+0x139/0x1a0
[ 92.155696] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 92.155703] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 92.155707] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 92.155710] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 92.155713] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 92.155716] [ T1842] elevator_change_done+0x26f/0x690
[ 92.155725] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 92.155728] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 92.155733] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 92.155737] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 92.155740] [ T1842] elevator_change+0x283/0x4f0
[ 92.155749] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 92.155752] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 92.155755] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 92.155759] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 92.155764] [ T1842] ? lock_acquire+0x126/0x140
[ 92.155773] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 92.155776] [ T1842] queue_attr_store+0x23f/0x360
[ 92.155779] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 92.155782] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 92.155785] [ T1842] ? lock_release+0xfa/0x120
[ 92.155793] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 92.155796] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 92.155801] [ T1842] ? lock_acquire+0x126/0x140
[ 92.155804] [ T1842] ? lock_acquire+0x126/0x140
[ 92.155807] [ T1842] ? lock_release+0xfa/0x120
[ 92.155811] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 92.155816] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 92.155820] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 92.155823] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 92.155826] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 92.155829] [ T1842] vfs_write+0x524/0x1010
[ 92.155843] [ T1842] ? __pfx_do_raw_spin_lock+0x10/0x10
[ 92.155845] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 92.155850] [ T1842] ? do_fcntl+0x605/0x1030
[ 92.155860] [ T1842] ? __pfx_do_fcntl+0x10/0x10
[ 92.155864] [ T1842] ksys_write+0xff/0x200
[ 92.155867] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 92.155869] [ T1842] ? selinux_file_fcntl+0x1e/0x110
[ 92.155876] [ T1842] ? __pfx_pte_val+0x10/0x10
[ 92.155881] [ T1842] do_syscall_64+0xf4/0x660
[ 92.155885] [ T1842] ? ptep_set_access_flags+0xe5/0x130
[ 92.155888] [ T1842] ? __pfx_folio_xchg_last_cpupid+0x10/0x10
[ 92.155892] [ T1842] ? __pfx_ptep_set_access_flags+0x10/0x10
[ 92.155897] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 92.155901] [ T1842] ? lock_release+0xfa/0x120
[ 92.155904] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 92.155907] [ T1842] ? wp_page_reuse+0x160/0x1e0
[ 92.155911] [ T1842] ? do_wp_page+0x57e/0xf40
[ 92.155917] [ T1842] ? handle_pte_fault+0x54e/0x760
[ 92.155959] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 92.155982] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 92.155991] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 92.155998] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 92.156003] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 92.156017] [ T1842] ? count_memcg_events+0x37f/0x480
[ 92.156028] [ T1842] ? lock_release+0xfa/0x120
[ 92.156033] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 92.156036] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 92.156039] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 92.156044] [ T1842] ? lock_release+0xfa/0x120
[ 92.156057] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 92.156060] [ T1842] ? irqentry_exit+0xb0/0x810
[ 92.156063] [ T1842] ? do_syscall_64+0x34/0x660
[ 92.156066] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 92.156073] [ T1842] ? irqentry_exit+0xb5/0x810
[ 92.156075] [ T1842] ? do_syscall_64+0xab/0x660
[ 92.156079] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 92.156081] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 92.156085] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 92.156087] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 92.156096] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 92.156098] [ T1842] RDX: 000000000000000c RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 92.156100] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 92.156102] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000c
[ 92.156103] [ T1842] R13: 000000000000000c R14: 0000562ec532aa50 R15: 0000562ec5394f20
[ 92.156108] [ T1842] </TASK>
[ 92.156122] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 92.163427] [ T1841] RDX: 00670031c00000fa RSI: 0338018e000007d2 RDI: ffff888148d6f838
[ 92.701628] [ T1841] RBP: ffff888148d6f838 R08: ffffffffa7baa33a R09: fffffbfff5c10688
[ 92.717075] [ T1841] R10: fffffbfff5c10689 R11: 0000000000000001 R12: ffff88818265ad40
[ 92.732771] [ T1841] R13: ffff888148d6f838 R14: ffff888148d6f838 R15: 0338018e00000732
[ 92.748062] [ T1841] FS: 00007f96f4807780(0000) GS:ffff8887aff48000(0000) knlGS:0000000000000000
[ 92.763917] [ T1841] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 92.779232] [ T1841] CR2: 0000562ec532aa50 CR3: 0000000144fee003 CR4: 00000000001726f0
[ 92.831074] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 92.841145] [ T1842] CPU: 3 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 92.841152] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 92.841154] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 92.841155] [ T1842] Call Trace:
[ 92.841157] [ T1842] <TASK>
[ 92.841159] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 92.841168] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 92.841173] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 92.841179] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 92.841183] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 92.841188] [ T1842] ? kfree+0x1d6/0x620
[ 92.841192] [ T1842] kobject_add_internal+0x26f/0x800
[ 92.841197] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 92.841200] [ T1842] kobject_add+0x139/0x1a0
[ 92.841203] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 92.841208] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 92.841212] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 92.841215] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 92.841219] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 92.841222] [ T1842] elevator_change_done+0x26f/0x690
[ 92.841227] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 92.841230] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 92.841236] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 92.841239] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 92.841242] [ T1842] elevator_change+0x283/0x4f0
[ 92.841246] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 92.841249] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 92.841253] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 92.841256] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 92.841261] [ T1842] ? lock_acquire+0x126/0x140
[ 92.841266] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 92.841269] [ T1842] queue_attr_store+0x23f/0x360
[ 92.841273] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 92.841276] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 92.841279] [ T1842] ? lock_release+0xfa/0x120
[ 92.841283] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 92.841286] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 92.841290] [ T1842] ? lock_acquire+0x126/0x140
[ 92.841294] [ T1842] ? lock_acquire+0x126/0x140
[ 92.841297] [ T1842] ? lock_release+0xfa/0x120
[ 92.841301] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 92.841304] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 92.841307] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 92.841310] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 92.841314] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 92.841317] [ T1842] vfs_write+0x524/0x1010
[ 92.841321] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 92.841327] [ T1842] ksys_write+0xff/0x200
[ 92.841330] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 92.841333] [ T1842] ? count_memcg_events+0x37f/0x480
[ 92.841338] [ T1842] do_syscall_64+0xf4/0x660
[ 92.841342] [ T1842] ? lock_release+0xfa/0x120
[ 92.841345] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 92.841349] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 92.841353] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 92.841358] [ T1842] ? lock_release+0xfa/0x120
[ 92.841362] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 92.841365] [ T1842] ? irqentry_exit+0xb0/0x810
[ 92.841368] [ T1842] ? do_syscall_64+0x34/0x660
[ 92.841371] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 92.841374] [ T1842] ? irqentry_exit+0xb5/0x810
[ 92.841376] [ T1842] ? do_syscall_64+0xab/0x660
[ 92.841380] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 92.841382] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 92.841386] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 92.841389] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 92.841393] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 92.841395] [ T1842] RDX: 000000000000000c RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 92.841397] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 92.841398] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000c
[ 92.841400] [ T1842] R13: 000000000000000c R14: 0000562ec532aa50 R15: 0000562ec5382090
[ 92.841405] [ T1842] </TASK>
[ 92.841410] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 93.347152] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 93.357995] [ T1842] CPU: 7 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 93.358003] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 93.358004] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 93.358006] [ T1842] Call Trace:
[ 93.358008] [ T1842] <TASK>
[ 93.358015] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 93.358025] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 93.358030] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 93.358042] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 93.358047] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 93.358051] [ T1842] ? kasan_save_track+0x14/0x30
[ 93.358060] [ T1842] ? kfree+0x1d6/0x620
[ 93.358064] [ T1842] kobject_add_internal+0x26f/0x800
[ 93.358071] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 93.358074] [ T1842] kobject_add+0x139/0x1a0
[ 93.358085] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 93.358090] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 93.358094] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 93.358097] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 93.358109] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 93.358112] [ T1842] elevator_change_done+0x26f/0x690
[ 93.358122] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 93.358125] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 93.358131] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 93.358134] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 93.358137] [ T1842] elevator_change+0x283/0x4f0
[ 93.358144] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 93.358147] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 93.358151] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 93.358154] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 93.358160] [ T1842] ? lock_acquire+0x126/0x140
[ 93.358181] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 93.358190] [ T1842] queue_attr_store+0x23f/0x360
[ 93.358195] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 93.358198] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 93.358200] [ T1842] ? lock_release+0xfa/0x120
[ 93.358204] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 93.358211] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 93.358216] [ T1842] ? lock_acquire+0x126/0x140
[ 93.358219] [ T1842] ? lock_acquire+0x126/0x140
[ 93.358223] [ T1842] ? lock_release+0xfa/0x120
[ 93.358226] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 93.358238] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 93.358241] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 93.358244] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 93.358248] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 93.358254] [ T1842] vfs_write+0x524/0x1010
[ 93.358259] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 93.358262] [ T1842] ? __pfx_pte_val+0x10/0x10
[ 93.358266] [ T1842] ? ptep_set_access_flags+0xe5/0x130
[ 93.358274] [ T1842] ? __pfx_folio_xchg_last_cpupid+0x10/0x10
[ 93.358280] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 93.358282] [ T1842] ? lock_release+0xfa/0x120
[ 93.358285] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 93.358290] [ T1842] ksys_write+0xff/0x200
[ 93.358297] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 93.358300] [ T1842] ? handle_pte_fault+0x54e/0x760
[ 93.358305] [ T1842] do_syscall_64+0xf4/0x660
[ 93.358310] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 93.358317] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 93.358324] [ T1842] ? fput_close+0x137/0x1a0
[ 93.358328] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 93.358349] [ T1842] ? count_memcg_events+0x37f/0x480
[ 93.358365] [ T1842] ? lock_release+0xfa/0x120
[ 93.358371] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 93.358375] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 93.358381] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 93.358390] [ T1842] ? lock_release+0xfa/0x120
[ 93.358395] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 93.358400] [ T1842] ? irqentry_exit+0xb0/0x810
[ 93.358415] [ T1842] ? do_syscall_64+0x34/0x660
[ 93.358420] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 93.358427] [ T1842] ? irqentry_exit+0xb5/0x810
[ 93.358430] [ T1842] ? do_syscall_64+0xab/0x660
[ 93.358436] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 93.358440] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 93.358450] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 93.358453] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 93.358459] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 93.358462] [ T1842] RDX: 0000000000000006 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 93.358465] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 93.358469] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
[ 93.358471] [ T1842] R13: 0000000000000006 R14: 0000562ec532aa50 R15: 0000562ec53929c0
[ 93.358478] [ T1842] </TASK>
[ 93.358495] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 93.906005] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 93.916008] [ T1842] CPU: 0 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 93.916015] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 93.916017] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 93.916018] [ T1842] Call Trace:
[ 93.916020] [ T1842] <TASK>
[ 93.916022] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 93.916031] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 93.916037] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 93.916043] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 93.916048] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 93.916052] [ T1842] ? kfree+0x1d6/0x620
[ 93.916056] [ T1842] kobject_add_internal+0x26f/0x800
[ 93.916062] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 93.916065] [ T1842] kobject_add+0x139/0x1a0
[ 93.916069] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 93.916073] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 93.916077] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 93.916080] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 93.916085] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 93.916088] [ T1842] elevator_change_done+0x26f/0x690
[ 93.916093] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 93.916096] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 93.916102] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 93.916106] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 93.916109] [ T1842] elevator_change+0x283/0x4f0
[ 93.916113] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 93.916116] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 93.916120] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 93.916123] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 93.916129] [ T1842] ? lock_acquire+0x126/0x140
[ 93.916133] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 93.916137] [ T1842] queue_attr_store+0x23f/0x360
[ 93.916141] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 93.916144] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 93.916146] [ T1842] ? lock_release+0xfa/0x120
[ 93.916150] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 93.916154] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 93.916158] [ T1842] ? lock_acquire+0x126/0x140
[ 93.916162] [ T1842] ? lock_acquire+0x126/0x140
[ 93.916165] [ T1842] ? lock_release+0xfa/0x120
[ 93.916169] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 93.916172] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 93.916176] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 93.916179] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 93.916183] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 93.916185] [ T1842] vfs_write+0x524/0x1010
[ 93.916189] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 93.916193] [ T1842] ? fput_close+0x137/0x1a0
[ 93.916198] [ T1842] ? __pfx_pte_val+0x10/0x10
[ 93.916202] [ T1842] ksys_write+0xff/0x200
[ 93.916205] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 93.916208] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 93.916211] [ T1842] ? lock_release+0xfa/0x120
[ 93.916215] [ T1842] do_syscall_64+0xf4/0x660
[ 93.916219] [ T1842] ? do_wp_page+0x57e/0xf40
[ 93.916224] [ T1842] ? handle_pte_fault+0x54e/0x760
[ 93.916228] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 93.916231] [ T1842] ? fput_close_sync+0x137/0x1a0
[ 93.916234] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 93.916238] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 93.916242] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 93.916249] [ T1842] ? count_memcg_events+0x37f/0x480
[ 93.916255] [ T1842] ? lock_release+0xfa/0x120
[ 93.916258] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 93.916261] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 93.916265] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 93.916270] [ T1842] ? lock_release+0xfa/0x120
[ 93.916274] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 93.916277] [ T1842] ? irqentry_exit+0xb0/0x810
[ 93.916280] [ T1842] ? do_syscall_64+0x34/0x660
[ 93.916283] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 93.916286] [ T1842] ? irqentry_exit+0xb5/0x810
[ 93.916289] [ T1842] ? do_syscall_64+0xab/0x660
[ 93.916292] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 93.916295] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 93.916299] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 93.916302] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 93.916306] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 93.916308] [ T1842] RDX: 000000000000000c RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 93.916310] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 93.916311] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000c
[ 93.916313] [ T1842] R13: 000000000000000c R14: 0000562ec532aa50 R15: 0000562ec5397300
[ 93.916318] [ T1842] </TASK>
[ 93.916324] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 94.437220] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 94.447276] [ T1842] CPU: 0 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 94.447287] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 94.447289] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 94.447292] [ T1842] Call Trace:
[ 94.447295] [ T1842] <TASK>
[ 94.447297] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 94.447310] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 94.447317] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 94.447326] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 94.447333] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 94.447338] [ T1842] ? kasan_save_track+0x14/0x30
[ 94.447344] [ T1842] ? kfree+0x1d6/0x620
[ 94.447350] [ T1842] kobject_add_internal+0x26f/0x800
[ 94.447390] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 94.447455] [ T1842] kobject_add+0x139/0x1a0
[ 94.447521] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 94.447630] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 94.447696] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 94.447761] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 94.447849] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 94.447915] [ T1842] elevator_change_done+0x26f/0x690
[ 94.447943] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 94.447947] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 94.448008] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 94.448094] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 94.448117] [ T1842] elevator_change+0x283/0x4f0
[ 94.448204] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 94.448291] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 94.448379] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 94.448422] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 94.448552] [ T1842] ? lock_acquire+0x126/0x140
[ 94.448619] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 94.448684] [ T1842] queue_attr_store+0x23f/0x360
[ 94.448771] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 94.448837] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 94.448880] [ T1842] ? lock_release+0xfa/0x120
[ 94.448926] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 94.448933] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 94.449011] [ T1842] ? lock_acquire+0x126/0x140
[ 94.449077] [ T1842] ? lock_acquire+0x126/0x140
[ 94.449121] [ T1842] ? lock_release+0xfa/0x120
[ 94.449186] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 94.449251] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 94.449296] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 94.449360] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 94.449426] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 94.449513] [ T1842] vfs_write+0x524/0x1010
[ 94.449622] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 94.449688] [ T1842] ksys_write+0xff/0x200
[ 94.449732] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 94.449797] [ T1842] ? lock_release+0xfa/0x120
[ 94.449862] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 94.449933] [ T1842] do_syscall_64+0xf4/0x660
[ 94.449940] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 94.449945] [ T1842] ? irqentry_exit+0xb5/0x810
[ 94.449961] [ T1842] ? do_syscall_64+0xab/0x660
[ 94.449983] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 94.449988] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 94.450027] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 94.450071] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 94.450179] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 94.450223] [ T1842] RDX: 0000000000000006 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 94.450246] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 94.450289] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
[ 94.450311] [ T1842] R13: 0000000000000006 R14: 0000562ec532aa50 R15: 0000562ec5395410
[ 94.450420] [ T1842] </TASK>
[ 95.163048] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 95.211096] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 95.221135] [ T1842] CPU: 7 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 95.221215] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 95.221258] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 95.221260] [ T1842] Call Trace:
[ 95.221303] [ T1842] <TASK>
[ 95.221367] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 95.221528] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 95.221636] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 95.221768] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 95.221855] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 95.221943] [ T1842] ? kfree+0x1d6/0x620
[ 95.221950] [ T1842] kobject_add_internal+0x26f/0x800
[ 95.221958] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 95.222036] [ T1842] kobject_add+0x139/0x1a0
[ 95.222102] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 95.222210] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 95.222297] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 95.222363] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 95.222451] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 95.222495] [ T1842] elevator_change_done+0x26f/0x690
[ 95.222624] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 95.222690] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 95.222798] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 95.222865] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 95.222930] [ T1842] elevator_change+0x283/0x4f0
[ 95.222958] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 95.222963] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 95.222969] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 95.222974] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 95.222984] [ T1842] ? lock_acquire+0x126/0x140
[ 95.222992] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 95.222997] [ T1842] queue_attr_store+0x23f/0x360
[ 95.223003] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 95.223009] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 95.223014] [ T1842] ? lock_release+0xfa/0x120
[ 95.223031] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 95.223117] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 95.223204] [ T1842] ? lock_acquire+0x126/0x140
[ 95.223249] [ T1842] ? lock_acquire+0x126/0x140
[ 95.223314] [ T1842] ? lock_release+0xfa/0x120
[ 95.223379] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 95.223444] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 95.223489] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 95.223553] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 95.223640] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 95.223684] [ T1842] vfs_write+0x524/0x1010
[ 95.223772] [ T1842] ? __pfx_locks_remove_posix+0x10/0x10
[ 95.223902] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 95.223953] [ T1842] ksys_write+0xff/0x200
[ 95.223972] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 95.223977] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 95.224036] [ T1842] ? lock_release+0xfa/0x120
[ 95.224122] [ T1842] do_syscall_64+0xf4/0x660
[ 95.224189] [ T1842] ? do_wp_page+0x57e/0xf40
[ 95.224256] [ T1842] ? handle_pte_fault+0x54e/0x760
[ 95.224340] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 95.224385] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 95.224429] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 95.224516] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 95.224690] [ T1842] ? count_memcg_events+0x37f/0x480
[ 95.224777] [ T1842] ? lock_release+0xfa/0x120
[ 95.224843] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 95.224908] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 95.224954] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 95.224973] [ T1842] ? lock_release+0xfa/0x120
[ 95.225039] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 95.225084] [ T1842] ? irqentry_exit+0xb0/0x810
[ 95.225148] [ T1842] ? do_syscall_64+0x34/0x660
[ 95.225214] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 95.225279] [ T1842] ? irqentry_exit+0xb5/0x810
[ 95.225322] [ T1842] ? do_syscall_64+0xab/0x660
[ 95.225388] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 95.225454] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 95.225562] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 95.225628] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 95.225715] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 95.225780] [ T1842] RDX: 000000000000000c RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 95.225803] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 95.225846] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000c
[ 95.225890] [ T1842] R13: 000000000000000c R14: 0000562ec532aa50 R15: 0000562ec5395360
[ 95.225959] [ T1842] </TASK>
[ 96.121095] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 96.243207] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 96.254050] [ T1842] CPU: 7 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 96.254058] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 96.254064] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 96.254066] [ T1842] Call Trace:
[ 96.254068] [ T1842] <TASK>
[ 96.254070] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 96.254079] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 96.254089] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 96.254096] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 96.254100] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 96.254111] [ T1842] ? kfree+0x1d6/0x620
[ 96.254115] [ T1842] kobject_add_internal+0x26f/0x800
[ 96.254121] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 96.254127] [ T1842] kobject_add+0x139/0x1a0
[ 96.254131] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 96.254135] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 96.254139] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 96.254142] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 96.254151] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 96.254154] [ T1842] elevator_change_done+0x26f/0x690
[ 96.254159] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 96.254162] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 96.254170] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 96.254174] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 96.254177] [ T1842] elevator_change+0x283/0x4f0
[ 96.254180] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 96.254183] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 96.254187] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 96.254192] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 96.254198] [ T1842] ? lock_acquire+0x126/0x140
[ 96.254202] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 96.254205] [ T1842] queue_attr_store+0x23f/0x360
[ 96.254209] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 96.254216] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 96.254219] [ T1842] ? lock_release+0xfa/0x120
[ 96.254223] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 96.254227] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 96.254231] [ T1842] ? lock_acquire+0x126/0x140
[ 96.254235] [ T1842] ? lock_acquire+0x126/0x140
[ 96.254238] [ T1842] ? lock_release+0xfa/0x120
[ 96.254242] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 96.254245] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 96.254248] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 96.254251] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 96.254265] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 96.254268] [ T1842] vfs_write+0x524/0x1010
[ 96.254272] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 96.254284] [ T1842] ksys_write+0xff/0x200
[ 96.254287] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 96.254290] [ T1842] ? lock_release+0xfa/0x120
[ 96.254294] [ T1842] do_syscall_64+0xf4/0x660
[ 96.254301] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 96.254307] [ T1842] ? lock_release+0xfa/0x120
[ 96.254310] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 96.254314] [ T1842] ? irqentry_exit+0xb0/0x810
[ 96.254316] [ T1842] ? do_syscall_64+0x34/0x660
[ 96.254321] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 96.254326] [ T1842] ? irqentry_exit+0xb5/0x810
[ 96.254328] [ T1842] ? do_syscall_64+0xab/0x660
[ 96.254331] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 96.254334] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 96.254338] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 96.254348] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 96.254352] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 96.254354] [ T1842] RDX: 000000000000000c RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 96.254356] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 96.254357] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000c
[ 96.254359] [ T1842] R13: 000000000000000c R14: 0000562ec532aa50 R15: 0000562ec53956a0
[ 96.254373] [ T1842] </TASK>
[ 96.254379] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 96.715123] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 96.725123] [ T1842] CPU: 3 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 96.725129] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 96.725131] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 96.725133] [ T1842] Call Trace:
[ 96.725135] [ T1842] <TASK>
[ 96.725136] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 96.725145] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 96.725150] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 96.725156] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 96.725161] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 96.725165] [ T1842] ? kfree+0x1d6/0x620
[ 96.725169] [ T1842] kobject_add_internal+0x26f/0x800
[ 96.725175] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 96.725178] [ T1842] kobject_add+0x139/0x1a0
[ 96.725181] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 96.725185] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 96.725189] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 96.725192] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 96.725196] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 96.725199] [ T1842] elevator_change_done+0x26f/0x690
[ 96.725204] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 96.725207] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 96.725212] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 96.725216] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 96.725219] [ T1842] elevator_change+0x283/0x4f0
[ 96.725223] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 96.725226] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 96.725230] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 96.725233] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 96.725238] [ T1842] ? lock_acquire+0x126/0x140
[ 96.725243] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 96.725245] [ T1842] queue_attr_store+0x23f/0x360
[ 96.725249] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 96.725252] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 96.725255] [ T1842] ? lock_release+0xfa/0x120
[ 96.725259] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 96.725262] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 96.725267] [ T1842] ? lock_acquire+0x126/0x140
[ 96.725270] [ T1842] ? lock_acquire+0x126/0x140
[ 96.725274] [ T1842] ? lock_release+0xfa/0x120
[ 96.725277] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 96.725280] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 96.725284] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 96.725286] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 96.725290] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 96.725293] [ T1842] vfs_write+0x524/0x1010
[ 96.725297] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 96.725302] [ T1842] ? __pfx_do_raw_spin_lock+0x10/0x10
[ 96.725304] [ T1842] ? lock_acquire+0x126/0x140
[ 96.725308] [ T1842] ksys_write+0xff/0x200
[ 96.725311] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 96.725314] [ T1842] ? __pfx_pte_val+0x10/0x10
[ 96.725318] [ T1842] ? folio_xchg_last_cpupid+0xc6/0x130
[ 96.725323] [ T1842] do_syscall_64+0xf4/0x660
[ 96.725327] [ T1842] ? __pfx_ptep_set_access_flags+0x10/0x10
[ 96.725331] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 96.725334] [ T1842] ? lock_release+0xfa/0x120
[ 96.725337] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 96.725340] [ T1842] ? wp_page_reuse+0x160/0x1e0
[ 96.725344] [ T1842] ? do_wp_page+0x57e/0xf40
[ 96.725348] [ T1842] ? handle_pte_fault+0x54e/0x760
[ 96.725352] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 96.725355] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 96.725359] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 96.725363] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 96.725370] [ T1842] ? count_memcg_events+0x37f/0x480
[ 96.725375] [ T1842] ? lock_release+0xfa/0x120
[ 96.725378] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 96.725381] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 96.725385] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 96.725389] [ T1842] ? lock_release+0xfa/0x120
[ 96.725393] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 96.725396] [ T1842] ? irqentry_exit+0xb0/0x810
[ 96.725399] [ T1842] ? do_syscall_64+0x34/0x660
[ 96.725402] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 96.725405] [ T1842] ? irqentry_exit+0xb5/0x810
[ 96.725407] [ T1842] ? do_syscall_64+0xab/0x660
[ 96.725411] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 96.725413] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 96.725417] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 96.725419] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 96.725423] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 96.725425] [ T1842] RDX: 0000000000000004 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 96.725427] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 96.725429] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004
[ 96.725430] [ T1842] R13: 0000000000000004 R14: 0000562ec532aa50 R15: 0000562ec5399dc0
[ 96.725435] [ T1842] </TASK>
[ 96.725440] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 97.266189] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 97.276171] [ T1842] CPU: 7 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 97.276178] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 97.276179] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 97.276181] [ T1842] Call Trace:
[ 97.276183] [ T1842] <TASK>
[ 97.276185] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 97.276194] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 97.276199] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 97.276206] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 97.276210] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 97.276214] [ T1842] ? kasan_save_track+0x14/0x30
[ 97.276218] [ T1842] ? kfree+0x1d6/0x620
[ 97.276222] [ T1842] kobject_add_internal+0x26f/0x800
[ 97.276228] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 97.276232] [ T1842] kobject_add+0x139/0x1a0
[ 97.276235] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 97.276239] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 97.276243] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 97.276246] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 97.276250] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 97.276253] [ T1842] elevator_change_done+0x26f/0x690
[ 97.276259] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 97.276262] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 97.276268] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 97.276272] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 97.276275] [ T1842] elevator_change+0x283/0x4f0
[ 97.276279] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 97.276282] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 97.276286] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 97.276289] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 97.276295] [ T1842] ? lock_acquire+0x126/0x140
[ 97.276300] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 97.276303] [ T1842] queue_attr_store+0x23f/0x360
[ 97.276307] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 97.276310] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 97.276313] [ T1842] ? lock_release+0xfa/0x120
[ 97.276317] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 97.276321] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 97.276325] [ T1842] ? lock_acquire+0x126/0x140
[ 97.276329] [ T1842] ? lock_acquire+0x126/0x140
[ 97.276332] [ T1842] ? lock_release+0xfa/0x120
[ 97.276336] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 97.276339] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 97.276343] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 97.276345] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 97.276349] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 97.276352] [ T1842] vfs_write+0x524/0x1010
[ 97.276356] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 97.276361] [ T1842] ? __pfx_fput_close_sync+0x10/0x10
[ 97.276365] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 97.276369] [ T1842] ksys_write+0xff/0x200
[ 97.276372] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 97.276374] [ T1842] ? ptep_set_access_flags+0xe5/0x130
[ 97.276378] [ T1842] ? __pfx_ptep_set_access_flags+0x10/0x10
[ 97.276381] [ T1842] do_syscall_64+0xf4/0x660
[ 97.276386] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 97.276390] [ T1842] ? wp_page_reuse+0x160/0x1e0
[ 97.276394] [ T1842] ? do_wp_page+0x57e/0xf40
[ 97.276398] [ T1842] ? handle_pte_fault+0x54e/0x760
[ 97.276402] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 97.276406] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 97.276410] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 97.276414] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 97.276422] [ T1842] ? count_memcg_events+0x37f/0x480
[ 97.276428] [ T1842] ? lock_release+0xfa/0x120
[ 97.276431] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 97.276434] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 97.276437] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 97.276443] [ T1842] ? lock_release+0xfa/0x120
[ 97.276446] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 97.276450] [ T1842] ? irqentry_exit+0xb0/0x810
[ 97.276452] [ T1842] ? do_syscall_64+0x34/0x660
[ 97.276456] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 97.276458] [ T1842] ? irqentry_exit+0xb5/0x810
[ 97.276461] [ T1842] ? do_syscall_64+0xab/0x660
[ 97.276464] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 97.276467] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 97.276470] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 97.276473] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 97.276477] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 97.276479] [ T1842] RDX: 0000000000000006 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 97.276481] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 97.276483] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
[ 97.276484] [ T1842] R13: 0000000000000006 R14: 0000562ec532aa50 R15: 0000562ec53972c0
[ 97.276489] [ T1842] </TASK>
[ 97.276495] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 97.804201] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 97.814639] [ T1842] CPU: 7 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 97.814813] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 97.814835] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 97.814879] [ T1842] Call Trace:
[ 97.814923] [ T1842] <TASK>
[ 97.814988] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 97.815022] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 97.815123] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 97.815233] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 97.815320] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 97.815407] [ T1842] ? kfree+0x1d6/0x620
[ 97.815494] [ T1842] kobject_add_internal+0x26f/0x800
[ 97.815605] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 97.815669] [ T1842] kobject_add+0x139/0x1a0
[ 97.815734] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 97.815843] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 97.815888] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 97.815931] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 97.815998] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 97.816004] [ T1842] elevator_change_done+0x26f/0x690
[ 97.816105] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 97.816149] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 97.816237] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 97.816323] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 97.816367] [ T1842] elevator_change+0x283/0x4f0
[ 97.816454] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 97.816520] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 97.816564] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 97.816585] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 97.816672] [ T1842] ? lock_acquire+0x126/0x140
[ 97.816803] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 97.816847] [ T1842] queue_attr_store+0x23f/0x360
[ 97.816935] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 97.817002] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 97.817007] [ T1842] ? lock_release+0xfa/0x120
[ 97.817014] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 97.817052] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 97.817073] [ T1842] ? lock_acquire+0x126/0x140
[ 97.817139] [ T1842] ? lock_acquire+0x126/0x140
[ 97.817183] [ T1842] ? lock_release+0xfa/0x120
[ 97.817205] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 97.817269] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 97.817335] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 97.817400] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 97.817467] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 97.817509] [ T1842] vfs_write+0x524/0x1010
[ 97.817597] [ T1842] ? folio_xchg_last_cpupid+0xc6/0x130
[ 97.817667] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 97.817684] [ T1842] ? __pfx_folio_xchg_last_cpupid+0x10/0x10
[ 97.817772] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 97.817859] [ T1842] ? do_wp_page+0x57e/0xf40
[ 97.817926] [ T1842] ksys_write+0xff/0x200
[ 97.817989] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 97.818005] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 97.818033] [ T1842] do_syscall_64+0xf4/0x660
[ 97.818103] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 97.818143] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 97.818295] [ T1842] ? count_memcg_events+0x37f/0x480
[ 97.818405] [ T1842] ? lock_release+0xfa/0x120
[ 97.818471] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 97.818557] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 97.818624] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 97.818733] [ T1842] ? lock_release+0xfa/0x120
[ 97.818818] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 97.818885] [ T1842] ? irqentry_exit+0xb0/0x810
[ 97.818929] [ T1842] ? do_syscall_64+0x34/0x660
[ 97.818995] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 97.819000] [ T1842] ? irqentry_exit+0xb5/0x810
[ 97.819016] [ T1842] ? do_syscall_64+0xab/0x660
[ 97.819103] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 97.819169] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 97.819256] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 97.819300] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 97.819408] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 97.819452] [ T1842] RDX: 0000000000000004 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 97.819475] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 97.819539] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004
[ 97.819543] [ T1842] R13: 0000000000000004 R14: 0000562ec532aa50 R15: 0000562ec53997a0
[ 97.819649] [ T1842] </TASK>
[ 98.701369] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 98.743363] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 98.753340] [ T1842] CPU: 0 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 98.753346] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 98.753347] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 98.753349] [ T1842] Call Trace:
[ 98.753351] [ T1842] <TASK>
[ 98.753353] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 98.753362] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 98.753367] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 98.753373] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 98.753377] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 98.753381] [ T1842] ? kasan_save_track+0x14/0x30
[ 98.753385] [ T1842] ? kfree+0x1d6/0x620
[ 98.753388] [ T1842] kobject_add_internal+0x26f/0x800
[ 98.753395] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 98.753398] [ T1842] kobject_add+0x139/0x1a0
[ 98.753402] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 98.753406] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 98.753410] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 98.753413] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 98.753417] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 98.753420] [ T1842] elevator_change_done+0x26f/0x690
[ 98.753426] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 98.753429] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 98.753435] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 98.753439] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 98.753442] [ T1842] elevator_change+0x283/0x4f0
[ 98.753446] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 98.753449] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 98.753453] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 98.753456] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 98.753461] [ T1842] ? lock_acquire+0x126/0x140
[ 98.753466] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 98.753469] [ T1842] queue_attr_store+0x23f/0x360
[ 98.753473] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 98.753476] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 98.753479] [ T1842] ? lock_release+0xfa/0x120
[ 98.753482] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 98.753486] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 98.753490] [ T1842] ? lock_acquire+0x126/0x140
[ 98.753494] [ T1842] ? lock_acquire+0x126/0x140
[ 98.753497] [ T1842] ? lock_release+0xfa/0x120
[ 98.753501] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 98.753504] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 98.753508] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 98.753510] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 98.753514] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 98.753517] [ T1842] vfs_write+0x524/0x1010
[ 98.753521] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 98.753525] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 98.753528] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 98.753534] [ T1842] ? count_memcg_events+0x37f/0x480
[ 98.753540] [ T1842] ksys_write+0xff/0x200
[ 98.753543] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 98.753545] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 98.753550] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 98.753556] [ T1842] do_syscall_64+0xf4/0x660
[ 98.753561] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 98.753565] [ T1842] ? irqentry_exit+0xb0/0x810
[ 98.753567] [ T1842] ? do_syscall_64+0x34/0x660
[ 98.753571] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 98.753573] [ T1842] ? irqentry_exit+0xb5/0x810
[ 98.753576] [ T1842] ? do_syscall_64+0xab/0x660
[ 98.753579] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 98.753582] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 98.753585] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 98.753588] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 98.753592] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 98.753594] [ T1842] RDX: 0000000000000006 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 98.753596] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 98.753598] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
[ 98.753599] [ T1842] R13: 0000000000000006 R14: 0000562ec532aa50 R15: 0000562ec5399990
[ 98.753604] [ T1842] </TASK>
[ 98.753610] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 99.221237] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 99.231263] [ T1842] CPU: 0 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 99.231273] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 99.231275] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 99.231278] [ T1842] Call Trace:
[ 99.231280] [ T1842] <TASK>
[ 99.231283] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 99.231295] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 99.231355] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 99.231528] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 99.231594] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 99.231660] [ T1842] ? kfree+0x1d6/0x620
[ 99.231726] [ T1842] kobject_add_internal+0x26f/0x800
[ 99.231855] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 99.231921] [ T1842] kobject_add+0x139/0x1a0
[ 99.231965] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 99.232031] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 99.232039] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 99.232044] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 99.232081] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 99.232126] [ T1842] elevator_change_done+0x26f/0x690
[ 99.232234] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 99.232278] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 99.232387] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 99.232452] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 99.232496] [ T1842] elevator_change+0x283/0x4f0
[ 99.232583] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 99.232649] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 99.232715] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 99.232801] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 99.232888] [ T1842] ? lock_acquire+0x126/0x140
[ 99.232955] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 99.233019] [ T1842] queue_attr_store+0x23f/0x360
[ 99.233047] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 99.233052] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 99.233057] [ T1842] ? lock_release+0xfa/0x120
[ 99.233063] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 99.233070] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 99.233077] [ T1842] ? lock_acquire+0x126/0x140
[ 99.233082] [ T1842] ? lock_acquire+0x126/0x140
[ 99.233089] [ T1842] ? lock_release+0xfa/0x120
[ 99.233094] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 99.233100] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 99.233106] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 99.233163] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 99.233208] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 99.233228] [ T1842] vfs_write+0x524/0x1010
[ 99.233294] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 99.233381] [ T1842] ? wp_page_reuse+0x160/0x1e0
[ 99.233447] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 99.233584] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 99.233671] [ T1842] ksys_write+0xff/0x200
[ 99.233737] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 99.233824] [ T1842] do_syscall_64+0xf4/0x660
[ 99.233913] [ T1842] ? count_memcg_events+0x37f/0x480
[ 99.233977] [ T1842] ? lock_release+0xfa/0x120
[ 99.234023] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 99.234028] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 99.234045] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 99.234066] [ T1842] ? lock_release+0xfa/0x120
[ 99.234132] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 99.234197] [ T1842] ? irqentry_exit+0xb0/0x810
[ 99.234262] [ T1842] ? do_syscall_64+0x34/0x660
[ 99.234306] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 99.234328] [ T1842] ? irqentry_exit+0xb5/0x810
[ 99.234372] [ T1842] ? do_syscall_64+0xab/0x660
[ 99.234437] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 99.234524] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 99.234611] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 99.234676] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 99.234764] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 99.234808] [ T1842] RDX: 000000000000000c RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 99.234873] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 99.234895] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000c
[ 99.234918] [ T1842] R13: 000000000000000c R14: 0000562ec532aa50 R15: 0000562ec5399ad0
[ 99.235027] [ T1842] </TASK>
[ 100.030097] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 100.109352] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 100.119423] [ T1842] CPU: 6 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 100.119434] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 100.119436] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 100.119439] [ T1842] Call Trace:
[ 100.119442] [ T1842] <TASK>
[ 100.119444] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 100.119468] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 100.119534] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 100.119665] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 100.119751] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 100.119817] [ T1842] ? kasan_save_track+0x14/0x30
[ 100.119882] [ T1842] ? kfree+0x1d6/0x620
[ 100.119948] [ T1842] kobject_add_internal+0x26f/0x800
[ 100.120035] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 100.120061] [ T1842] kobject_add+0x139/0x1a0
[ 100.120066] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 100.120105] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 100.120170] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 100.120216] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 100.120302] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 100.120346] [ T1842] elevator_change_done+0x26f/0x690
[ 100.120454] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 100.120498] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 100.120628] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 100.120695] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 100.120760] [ T1842] elevator_change+0x283/0x4f0
[ 100.120829] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 100.120891] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 100.120977] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 100.121022] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 100.121052] [ T1842] ? lock_acquire+0x126/0x140
[ 100.121153] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 100.121219] [ T1842] queue_attr_store+0x23f/0x360
[ 100.121306] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 100.121372] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 100.121437] [ T1842] ? lock_release+0xfa/0x120
[ 100.121524] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 100.121589] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 100.121676] [ T1842] ? lock_acquire+0x126/0x140
[ 100.121721] [ T1842] ? lock_acquire+0x126/0x140
[ 100.121765] [ T1842] ? lock_release+0xfa/0x120
[ 100.121808] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 100.121895] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 100.121940] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 100.122004] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 100.122053] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 100.122058] [ T1842] vfs_write+0x524/0x1010
[ 100.122137] [ T1842] ? ptep_set_access_flags+0xe5/0x130
[ 100.122203] [ T1842] ? __pfx_folio_xchg_last_cpupid+0x10/0x10
[ 100.122224] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 100.122289] [ T1842] ? __pfx_ptep_set_access_flags+0x10/0x10
[ 100.122349] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 100.122406] [ T1842] ? lock_release+0xfa/0x120
[ 100.122471] [ T1842] ? do_wp_page+0x57e/0xf40
[ 100.122536] [ T1842] ksys_write+0xff/0x200
[ 100.122561] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 100.122603] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 100.122646] [ T1842] ? fput_close_sync+0x137/0x1a0
[ 100.122755] [ T1842] do_syscall_64+0xf4/0x660
[ 100.122864] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 100.122911] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 100.123040] [ T1842] ? count_memcg_events+0x37f/0x480
[ 100.123049] [ T1842] ? lock_release+0xfa/0x120
[ 100.123083] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 100.123148] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 100.123193] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 100.123280] [ T1842] ? lock_release+0xfa/0x120
[ 100.123324] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 100.123367] [ T1842] ? irqentry_exit+0xb0/0x810
[ 100.123411] [ T1842] ? do_syscall_64+0x34/0x660
[ 100.123457] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 100.123542] [ T1842] ? irqentry_exit+0xb5/0x810
[ 100.123585] [ T1842] ? do_syscall_64+0xab/0x660
[ 100.123650] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 100.123737] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 100.123825] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 100.123890] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 100.123956] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 100.124021] [ T1842] RDX: 0000000000000006 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 100.124044] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 100.124047] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
[ 100.124050] [ T1842] R13: 0000000000000006 R14: 0000562ec532aa50 R15: 0000562ec5394f20
[ 100.124110] [ T1842] </TASK>
[ 101.040053] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 101.115173] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 101.125215] [ T1842] CPU: 3 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 101.125222] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 101.125223] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 101.125225] [ T1842] Call Trace:
[ 101.125227] [ T1842] <TASK>
[ 101.125229] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 101.125238] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 101.125243] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 101.125249] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 101.125254] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 101.125258] [ T1842] ? kfree+0x1d6/0x620
[ 101.125262] [ T1842] kobject_add_internal+0x26f/0x800
[ 101.125268] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 101.125271] [ T1842] kobject_add+0x139/0x1a0
[ 101.125274] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 101.125278] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 101.125283] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 101.125285] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 101.125290] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 101.125293] [ T1842] elevator_change_done+0x26f/0x690
[ 101.125298] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 101.125301] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 101.125306] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 101.125310] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 101.125313] [ T1842] elevator_change+0x283/0x4f0
[ 101.125318] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 101.125321] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 101.125325] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 101.125328] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 101.125333] [ T1842] ? lock_acquire+0x126/0x140
[ 101.125338] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 101.125341] [ T1842] queue_attr_store+0x23f/0x360
[ 101.125345] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 101.125348] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 101.125351] [ T1842] ? lock_release+0xfa/0x120
[ 101.125355] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 101.125358] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 101.125363] [ T1842] ? lock_acquire+0x126/0x140
[ 101.125366] [ T1842] ? lock_acquire+0x126/0x140
[ 101.125370] [ T1842] ? lock_release+0xfa/0x120
[ 101.125373] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 101.125377] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 101.125380] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 101.125383] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 101.125387] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 101.125390] [ T1842] vfs_write+0x524/0x1010
[ 101.125394] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 101.125397] [ T1842] ? fput_close_sync+0x137/0x1a0
[ 101.125402] [ T1842] ? folio_xchg_last_cpupid+0xc6/0x130
[ 101.125406] [ T1842] ? do_syscall_64+0x1b9/0x660
[ 101.125410] [ T1842] ? ptep_set_access_flags+0xe5/0x130
[ 101.125414] [ T1842] ksys_write+0xff/0x200
[ 101.125418] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 101.125420] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 101.125424] [ T1842] ? wp_page_reuse+0x160/0x1e0
[ 101.125429] [ T1842] do_syscall_64+0xf4/0x660
[ 101.125432] [ T1842] ? handle_pte_fault+0x54e/0x760
[ 101.125437] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 101.125440] [ T1842] ? trace_hardirqs_on_prepare+0x150/0x1a0
[ 101.125444] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 101.125446] [ T1842] ? do_syscall_64+0x1d7/0x660
[ 101.125451] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 101.125455] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 101.125462] [ T1842] ? count_memcg_events+0x37f/0x480
[ 101.125467] [ T1842] ? lock_release+0xfa/0x120
[ 101.125471] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 101.125474] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 101.125477] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 101.125482] [ T1842] ? lock_release+0xfa/0x120
[ 101.125485] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 101.125489] [ T1842] ? irqentry_exit+0xb0/0x810
[ 101.125492] [ T1842] ? do_syscall_64+0x34/0x660
[ 101.125495] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 101.125497] [ T1842] ? irqentry_exit+0xb5/0x810
[ 101.125500] [ T1842] ? do_syscall_64+0xab/0x660
[ 101.125504] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 101.125506] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 101.125510] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 101.125513] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 101.125517] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 101.125519] [ T1842] RDX: 0000000000000004 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 101.125521] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 101.125523] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004
[ 101.125524] [ T1842] R13: 0000000000000004 R14: 0000562ec532aa50 R15: 0000562ec5382090
[ 101.125529] [ T1842] </TASK>
[ 101.125535] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 101.664224] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 101.675194] [ T1842] CPU: 0 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 101.675208] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 101.675210] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 101.675212] [ T1842] Call Trace:
[ 101.675214] [ T1842] <TASK>
[ 101.675216] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 101.675236] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 101.675245] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 101.675253] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 101.675258] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 101.675277] [ T1842] ? kfree+0x1d6/0x620
[ 101.675282] [ T1842] kobject_add_internal+0x26f/0x800
[ 101.675296] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 101.675300] [ T1842] kobject_add+0x139/0x1a0
[ 101.675304] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 101.675318] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 101.675323] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 101.675326] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 101.675336] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 101.675340] [ T1842] elevator_change_done+0x26f/0x690
[ 101.675346] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 101.675353] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 101.675361] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 101.675366] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 101.675369] [ T1842] elevator_change+0x283/0x4f0
[ 101.675382] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 101.675385] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 101.675390] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 101.675394] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 101.675403] [ T1842] ? lock_acquire+0x126/0x140
[ 101.675409] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 101.675413] [ T1842] queue_attr_store+0x23f/0x360
[ 101.675424] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 101.675427] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 101.675431] [ T1842] ? lock_release+0xfa/0x120
[ 101.675435] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 101.675443] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 101.675447] [ T1842] ? lock_acquire+0x126/0x140
[ 101.675451] [ T1842] ? lock_acquire+0x126/0x140
[ 101.675455] [ T1842] ? lock_release+0xfa/0x120
[ 101.675463] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 101.675467] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 101.675471] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 101.675474] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 101.675479] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 101.675484] [ T1842] vfs_write+0x524/0x1010
[ 101.675489] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 101.675493] [ T1842] ? __pfx_locks_remove_posix+0x10/0x10
[ 101.675518] [ T1842] ksys_write+0xff/0x200
[ 101.675521] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 101.675524] [ T1842] ? __pfx_pte_val+0x10/0x10
[ 101.675529] [ T1842] do_syscall_64+0xf4/0x660
[ 101.675543] [ T1842] ? ptep_set_access_flags+0xe5/0x130
[ 101.675547] [ T1842] ? __pfx_folio_xchg_last_cpupid+0x10/0x10
[ 101.675553] [ T1842] ? __pfx_ptep_set_access_flags+0x10/0x10
[ 101.675558] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 101.675560] [ T1842] ? lock_release+0xfa/0x120
[ 101.675564] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 101.675567] [ T1842] ? wp_page_reuse+0x160/0x1e0
[ 101.675572] [ T1842] ? do_wp_page+0x57e/0xf40
[ 101.675583] [ T1842] ? handle_pte_fault+0x54e/0x760
[ 101.675586] [ T1842] ? do_syscall_64+0x1d7/0x660
[ 101.675590] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 101.675592] [ T1842] ? do_syscall_64+0x1d7/0x660
[ 101.675601] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 101.675605] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 101.675609] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 101.675620] [ T1842] ? count_memcg_events+0x37f/0x480
[ 101.675629] [ T1842] ? lock_release+0xfa/0x120
[ 101.675633] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 101.675635] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 101.675639] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 101.675648] [ T1842] ? lock_release+0xfa/0x120
[ 101.675651] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 101.675655] [ T1842] ? irqentry_exit+0xb0/0x810
[ 101.675657] [ T1842] ? do_syscall_64+0x34/0x660
[ 101.675665] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 101.675673] [ T1842] ? irqentry_exit+0xb5/0x810
[ 101.675675] [ T1842] ? do_syscall_64+0xab/0x660
[ 101.675679] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 101.675692] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 101.675695] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 101.675698] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 101.675702] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 101.675707] [ T1842] RDX: 0000000000000004 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 101.675709] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 101.675710] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004
[ 101.675712] [ T1842] R13: 0000000000000004 R14: 0000562ec532aa50 R15: 0000562ec5397e70
[ 101.675717] [ T1842] </TASK>
[ 101.675723] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 102.235777] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 102.245750] [ T1842] CPU: 4 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 102.245756] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 102.245757] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 102.245759] [ T1842] Call Trace:
[ 102.245761] [ T1842] <TASK>
[ 102.245763] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 102.245771] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 102.245776] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 102.245782] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 102.245786] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 102.245789] [ T1842] ? kasan_save_track+0x14/0x30
[ 102.245793] [ T1842] ? kfree+0x1d6/0x620
[ 102.245796] [ T1842] kobject_add_internal+0x26f/0x800
[ 102.245802] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 102.245805] [ T1842] kobject_add+0x139/0x1a0
[ 102.245808] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 102.245812] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 102.245816] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 102.245819] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 102.245823] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 102.245826] [ T1842] elevator_change_done+0x26f/0x690
[ 102.245831] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 102.245834] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 102.245839] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 102.245843] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 102.245846] [ T1842] elevator_change+0x283/0x4f0
[ 102.245850] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 102.245853] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 102.245856] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 102.245860] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 102.245865] [ T1842] ? lock_acquire+0x126/0x140
[ 102.245869] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 102.245872] [ T1842] queue_attr_store+0x23f/0x360
[ 102.245876] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 102.245879] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 102.245882] [ T1842] ? lock_release+0xfa/0x120
[ 102.245885] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 102.245889] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 102.245893] [ T1842] ? lock_acquire+0x126/0x140
[ 102.245896] [ T1842] ? lock_acquire+0x126/0x140
[ 102.245900] [ T1842] ? lock_release+0xfa/0x120
[ 102.245903] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 102.245906] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 102.245910] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 102.245913] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 102.245917] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 102.245919] [ T1842] vfs_write+0x524/0x1010
[ 102.245922] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 102.245926] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 102.245930] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 102.245936] [ T1842] ? count_memcg_events+0x37f/0x480
[ 102.245941] [ T1842] ksys_write+0xff/0x200
[ 102.245944] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 102.245947] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 102.245951] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 102.245957] [ T1842] do_syscall_64+0xf4/0x660
[ 102.245961] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 102.245964] [ T1842] ? irqentry_exit+0xb0/0x810
[ 102.245967] [ T1842] ? do_syscall_64+0x34/0x660
[ 102.245970] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 102.245973] [ T1842] ? irqentry_exit+0xb5/0x810
[ 102.245975] [ T1842] ? do_syscall_64+0xab/0x660
[ 102.245979] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 102.245982] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 102.245985] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 102.245987] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 102.245991] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 102.245993] [ T1842] RDX: 0000000000000006 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 102.245995] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 102.245997] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
[ 102.245998] [ T1842] R13: 0000000000000006 R14: 0000562ec532aa50 R15: 0000562ec53929c0
[ 102.246003] [ T1842] </TASK>
[ 102.246009] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 102.718245] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 102.728223] [ T1842] CPU: 0 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 102.728230] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 102.728231] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 102.728233] [ T1842] Call Trace:
[ 102.728235] [ T1842] <TASK>
[ 102.728237] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 102.728246] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 102.728251] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 102.728259] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 102.728263] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 102.728267] [ T1842] ? kfree+0x1d6/0x620
[ 102.728272] [ T1842] kobject_add_internal+0x26f/0x800
[ 102.728278] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 102.728282] [ T1842] kobject_add+0x139/0x1a0
[ 102.728285] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 102.728289] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 102.728293] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 102.728296] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 102.728301] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 102.728304] [ T1842] elevator_change_done+0x26f/0x690
[ 102.728310] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 102.728313] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 102.728319] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 102.728322] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 102.728325] [ T1842] elevator_change+0x283/0x4f0
[ 102.728329] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 102.728332] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 102.728336] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 102.728340] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 102.728345] [ T1842] ? lock_acquire+0x126/0x140
[ 102.728350] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 102.728353] [ T1842] queue_attr_store+0x23f/0x360
[ 102.728358] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 102.728361] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 102.728363] [ T1842] ? lock_release+0xfa/0x120
[ 102.728367] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 102.728371] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 102.728375] [ T1842] ? lock_acquire+0x126/0x140
[ 102.728379] [ T1842] ? lock_acquire+0x126/0x140
[ 102.728382] [ T1842] ? lock_release+0xfa/0x120
[ 102.728386] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 102.728389] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 102.728393] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 102.728395] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 102.728399] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 102.728402] [ T1842] vfs_write+0x524/0x1010
[ 102.728406] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 102.728409] [ T1842] ? filp_close+0x25/0x40
[ 102.728415] [ T1842] ? do_syscall_64+0x1b9/0x660
[ 102.728420] [ T1842] ? __pfx_pte_val+0x10/0x10
[ 102.728425] [ T1842] ksys_write+0xff/0x200
[ 102.728428] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 102.728430] [ T1842] ? lock_release+0xfa/0x120
[ 102.728434] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 102.728437] [ T1842] ? wp_page_reuse+0x160/0x1e0
[ 102.728441] [ T1842] do_syscall_64+0xf4/0x660
[ 102.728445] [ T1842] ? handle_pte_fault+0x54e/0x760
[ 102.728450] [ T1842] ? do_syscall_64+0x1d7/0x660
[ 102.728453] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 102.728457] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 102.728459] [ T1842] ? __pfx_locks_remove_posix+0x10/0x10
[ 102.728465] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 102.728469] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 102.728477] [ T1842] ? count_memcg_events+0x37f/0x480
[ 102.728483] [ T1842] ? lock_release+0xfa/0x120
[ 102.728486] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 102.728489] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 102.728493] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 102.728497] [ T1842] ? lock_release+0xfa/0x120
[ 102.728501] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 102.728504] [ T1842] ? irqentry_exit+0xb0/0x810
[ 102.728507] [ T1842] ? do_syscall_64+0x34/0x660
[ 102.728510] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 102.728513] [ T1842] ? irqentry_exit+0xb5/0x810
[ 102.728515] [ T1842] ? do_syscall_64+0xab/0x660
[ 102.728519] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 102.728521] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 102.728525] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 102.728528] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 102.728532] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 102.728534] [ T1842] RDX: 000000000000000c RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 102.728536] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 102.728537] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000c
[ 102.728539] [ T1842] R13: 000000000000000c R14: 0000562ec532aa50 R15: 0000562ec5397300
[ 102.728544] [ T1842] </TASK>
[ 102.728549] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 103.292307] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 103.302399] [ T1842] CPU: 7 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 103.302408] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 103.302410] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 103.302422] [ T1842] Call Trace:
[ 103.302446] [ T1842] <TASK>
[ 103.302489] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 103.302728] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 103.302816] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 103.302990] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 103.303077] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 103.303124] [ T1842] ? kasan_save_track+0x14/0x30
[ 103.303129] [ T1842] ? kfree+0x1d6/0x620
[ 103.303135] [ T1842] kobject_add_internal+0x26f/0x800
[ 103.303258] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 103.303324] [ T1842] kobject_add+0x139/0x1a0
[ 103.303389] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 103.303476] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 103.303563] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 103.303629] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 103.303716] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 103.303782] [ T1842] elevator_change_done+0x26f/0x690
[ 103.303912] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 103.303978] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 103.304088] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 103.304114] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 103.304131] [ T1842] elevator_change+0x283/0x4f0
[ 103.304218] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 103.304262] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 103.304306] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 103.304349] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 103.304396] [ T1842] ? lock_acquire+0x126/0x140
[ 103.304481] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 103.304546] [ T1842] queue_attr_store+0x23f/0x360
[ 103.304612] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 103.304678] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 103.304699] [ T1842] ? lock_release+0xfa/0x120
[ 103.304785] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 103.304851] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 103.304960] [ T1842] ? lock_acquire+0x126/0x140
[ 103.305005] [ T1842] ? lock_acquire+0x126/0x140
[ 103.305091] [ T1842] ? lock_release+0xfa/0x120
[ 103.305117] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 103.305123] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 103.305129] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 103.305146] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 103.305211] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 103.305255] [ T1842] vfs_write+0x524/0x1010
[ 103.305279] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 103.305322] [ T1842] ? __pfx_pte_val+0x10/0x10
[ 103.305430] [ T1842] ? folio_xchg_last_cpupid+0xc6/0x130
[ 103.305539] [ T1842] ? __pfx_ptep_set_access_flags+0x10/0x10
[ 103.305649] [ T1842] ksys_write+0xff/0x200
[ 103.305715] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 103.305760] [ T1842] do_syscall_64+0xf4/0x660
[ 103.305802] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 103.305910] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 103.305934] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 103.305975] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 103.306106] [ T1842] ? count_memcg_events+0x37f/0x480
[ 103.306115] [ T1842] ? lock_release+0xfa/0x120
[ 103.306194] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 103.306260] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 103.306326] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 103.306434] [ T1842] ? lock_release+0xfa/0x120
[ 103.306478] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 103.306547] [ T1842] ? irqentry_exit+0xb0/0x810
[ 103.306609] [ T1842] ? do_syscall_64+0x34/0x660
[ 103.306674] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 103.306740] [ T1842] ? irqentry_exit+0xb5/0x810
[ 103.306783] [ T1842] ? do_syscall_64+0xab/0x660
[ 103.306870] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 103.306936] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 103.307023] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 103.307088] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 103.307114] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 103.307118] [ T1842] RDX: 0000000000000006 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 103.307133] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 103.307157] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
[ 103.307179] [ T1842] R13: 0000000000000006 R14: 0000562ec532aa50 R15: 0000562ec5395360
[ 103.307215] [ T1842] </TASK>
[ 104.197683] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 104.269345] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 104.279320] [ T1842] CPU: 3 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 104.279326] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 104.279327] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 104.279329] [ T1842] Call Trace:
[ 104.279331] [ T1842] <TASK>
[ 104.279333] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 104.279341] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 104.279346] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 104.279352] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 104.279356] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 104.279360] [ T1842] ? kasan_save_track+0x14/0x30
[ 104.279363] [ T1842] ? kfree+0x1d6/0x620
[ 104.279367] [ T1842] kobject_add_internal+0x26f/0x800
[ 104.279372] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 104.279375] [ T1842] kobject_add+0x139/0x1a0
[ 104.279379] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 104.279383] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 104.279387] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 104.279390] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 104.279394] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 104.279397] [ T1842] elevator_change_done+0x26f/0x690
[ 104.279402] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 104.279404] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 104.279410] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 104.279413] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 104.279416] [ T1842] elevator_change+0x283/0x4f0
[ 104.279420] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 104.279423] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 104.279427] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 104.279430] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 104.279435] [ T1842] ? lock_acquire+0x126/0x140
[ 104.279440] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 104.279443] [ T1842] queue_attr_store+0x23f/0x360
[ 104.279446] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 104.279449] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 104.279452] [ T1842] ? lock_release+0xfa/0x120
[ 104.279456] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 104.279460] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 104.279464] [ T1842] ? lock_acquire+0x126/0x140
[ 104.279467] [ T1842] ? lock_acquire+0x126/0x140
[ 104.279471] [ T1842] ? lock_release+0xfa/0x120
[ 104.279474] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 104.279477] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 104.279481] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 104.279484] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 104.279487] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 104.279490] [ T1842] vfs_write+0x524/0x1010
[ 104.279494] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 104.279497] [ T1842] ? folio_xchg_last_cpupid+0xc6/0x130
[ 104.279501] [ T1842] ? ptep_set_access_flags+0xe5/0x130
[ 104.279505] [ T1842] ? __pfx_folio_xchg_last_cpupid+0x10/0x10
[ 104.279509] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 104.279511] [ T1842] ? lock_release+0xfa/0x120
[ 104.279515] [ T1842] ksys_write+0xff/0x200
[ 104.279518] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 104.279521] [ T1842] ? handle_pte_fault+0x54e/0x760
[ 104.279526] [ T1842] do_syscall_64+0xf4/0x660
[ 104.279530] [ T1842] ? __x64_sys_fcntl+0x10d/0x1c0
[ 104.279534] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 104.279538] [ T1842] ? trace_hardirqs_on_prepare+0x150/0x1a0
[ 104.279542] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 104.279546] [ T1842] ? kmem_cache_free+0x144/0x5f0
[ 104.279549] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 104.279556] [ T1842] ? count_memcg_events+0x37f/0x480
[ 104.279561] [ T1842] ? lock_release+0xfa/0x120
[ 104.279565] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 104.279568] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 104.279571] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 104.279576] [ T1842] ? lock_release+0xfa/0x120
[ 104.279579] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 104.279583] [ T1842] ? irqentry_exit+0xb0/0x810
[ 104.279585] [ T1842] ? do_syscall_64+0x34/0x660
[ 104.279588] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 104.279591] [ T1842] ? irqentry_exit+0xb5/0x810
[ 104.279593] [ T1842] ? do_syscall_64+0xab/0x660
[ 104.279597] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 104.279599] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 104.279603] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 104.279605] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 104.279609] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 104.279611] [ T1842] RDX: 0000000000000006 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 104.279613] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 104.279614] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
[ 104.279616] [ T1842] R13: 0000000000000006 R14: 0000562ec532aa50 R15: 0000562ec5395470
[ 104.279621] [ T1842] </TASK>
[ 104.279626] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 104.808451] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 104.818469] [ T1842] CPU: 4 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 104.818479] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 104.818482] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 104.818485] [ T1842] Call Trace:
[ 104.818488] [ T1842] <TASK>
[ 104.818491] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 104.818502] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 104.818508] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 104.818514] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 104.818518] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 104.818522] [ T1842] ? kasan_save_track+0x14/0x30
[ 104.818525] [ T1842] ? kfree+0x1d6/0x620
[ 104.818528] [ T1842] kobject_add_internal+0x26f/0x800
[ 104.818534] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 104.818537] [ T1842] kobject_add+0x139/0x1a0
[ 104.818540] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 104.818544] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 104.818548] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 104.818551] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 104.818555] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 104.818558] [ T1842] elevator_change_done+0x26f/0x690
[ 104.818563] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 104.818566] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 104.818572] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 104.818575] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 104.818578] [ T1842] elevator_change+0x283/0x4f0
[ 104.818582] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 104.818585] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 104.818589] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 104.818592] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 104.818597] [ T1842] ? lock_acquire+0x126/0x140
[ 104.818602] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 104.818605] [ T1842] queue_attr_store+0x23f/0x360
[ 104.818609] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 104.818612] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 104.818614] [ T1842] ? lock_release+0xfa/0x120
[ 104.818618] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 104.818622] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 104.818626] [ T1842] ? lock_acquire+0x126/0x140
[ 104.818629] [ T1842] ? lock_acquire+0x126/0x140
[ 104.818633] [ T1842] ? lock_release+0xfa/0x120
[ 104.818636] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 104.818639] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 104.818643] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 104.818646] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 104.818649] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 104.818652] [ T1842] vfs_write+0x524/0x1010
[ 104.818656] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 104.818660] [ T1842] ? __pfx_pmd_val+0x10/0x10
[ 104.818664] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 104.818669] [ T1842] ksys_write+0xff/0x200
[ 104.818672] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 104.818675] [ T1842] ? count_memcg_events+0x37f/0x480
[ 104.818679] [ T1842] do_syscall_64+0xf4/0x660
[ 104.818684] [ T1842] ? lock_release+0xfa/0x120
[ 104.818688] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 104.818690] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 104.818694] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 104.818699] [ T1842] ? lock_release+0xfa/0x120
[ 104.818702] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 104.818706] [ T1842] ? irqentry_exit+0xb0/0x810
[ 104.818708] [ T1842] ? do_syscall_64+0x34/0x660
[ 104.818712] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 104.818715] [ T1842] ? irqentry_exit+0xb5/0x810
[ 104.818717] [ T1842] ? do_syscall_64+0xab/0x660
[ 104.818720] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 104.818723] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 104.818726] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 104.818729] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 104.818733] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 104.818735] [ T1842] RDX: 0000000000000006 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 104.818737] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 104.818739] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
[ 104.818740] [ T1842] R13: 0000000000000006 R14: 0000562ec532aa50 R15: 0000562ec5397d90
[ 104.818745] [ T1842] </TASK>
[ 104.818750] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 105.300372] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 105.310342] [ T1842] CPU: 0 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 105.310349] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 105.310350] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 105.310352] [ T1842] Call Trace:
[ 105.310354] [ T1842] <TASK>
[ 105.310355] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 105.310364] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 105.310370] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 105.310376] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 105.310381] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 105.310384] [ T1842] ? kasan_save_track+0x14/0x30
[ 105.310388] [ T1842] ? kfree+0x1d6/0x620
[ 105.310392] [ T1842] kobject_add_internal+0x26f/0x800
[ 105.310398] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 105.310401] [ T1842] kobject_add+0x139/0x1a0
[ 105.310405] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 105.310409] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 105.310413] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 105.310416] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 105.310420] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 105.310423] [ T1842] elevator_change_done+0x26f/0x690
[ 105.310429] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 105.310432] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 105.310438] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 105.310442] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 105.310444] [ T1842] elevator_change+0x283/0x4f0
[ 105.310448] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 105.310451] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 105.310456] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 105.310459] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 105.310464] [ T1842] ? lock_acquire+0x126/0x140
[ 105.310469] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 105.310472] [ T1842] queue_attr_store+0x23f/0x360
[ 105.310477] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 105.310480] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 105.310482] [ T1842] ? lock_release+0xfa/0x120
[ 105.310486] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 105.310490] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 105.310494] [ T1842] ? lock_acquire+0x126/0x140
[ 105.310497] [ T1842] ? lock_acquire+0x126/0x140
[ 105.310501] [ T1842] ? lock_release+0xfa/0x120
[ 105.310504] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 105.310508] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 105.310511] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 105.310514] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 105.310518] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 105.310521] [ T1842] vfs_write+0x524/0x1010
[ 105.310524] [ T1842] ? folio_xchg_last_cpupid+0xc6/0x130
[ 105.310529] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 105.310531] [ T1842] ? __pfx_folio_xchg_last_cpupid+0x10/0x10
[ 105.310536] [ T1842] ? do_raw_spin_unlock+0x59/0x230
[ 105.310539] [ T1842] ? do_wp_page+0x57e/0xf40
[ 105.310544] [ T1842] ksys_write+0xff/0x200
[ 105.310547] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 105.310550] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 105.310555] [ T1842] do_syscall_64+0xf4/0x660
[ 105.310560] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 105.310564] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 105.310572] [ T1842] ? count_memcg_events+0x37f/0x480
[ 105.310578] [ T1842] ? lock_release+0xfa/0x120
[ 105.310582] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 105.310585] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 105.310589] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 105.310595] [ T1842] ? lock_release+0xfa/0x120
[ 105.310599] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 105.310602] [ T1842] ? irqentry_exit+0xb0/0x810
[ 105.310605] [ T1842] ? do_syscall_64+0x34/0x660
[ 105.310608] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 105.310611] [ T1842] ? irqentry_exit+0xb5/0x810
[ 105.310613] [ T1842] ? do_syscall_64+0xab/0x660
[ 105.310617] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 105.310619] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 105.310623] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 105.310626] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 105.310629] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 105.310632] [ T1842] RDX: 0000000000000006 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 105.310633] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 105.310635] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
[ 105.310636] [ T1842] R13: 0000000000000006 R14: 0000562ec532aa50 R15: 0000562ec53956a0
[ 105.310641] [ T1842] </TASK>
[ 105.310646] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[ 105.851457] [ T1842] sysfs: cannot create duplicate filename '/devices/virtual/block/nullb1/queue/iosched'
[ 105.861445] [ T1842] CPU: 4 UID: 0 PID: 1842 Comm: check Tainted: G B D W 7.1.0-kts+ #57 PREEMPT(lazy)
[ 105.861456] [ T1842] Tainted: [B]=BAD_PAGE, [D]=DIE, [W]=WARN
[ 105.861458] [ T1842] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 105.861461] [ T1842] Call Trace:
[ 105.861464] [ T1842] <TASK>
[ 105.861467] [ T1842] dump_stack_lvl+0x6e/0xa0
[ 105.861479] [ T1842] sysfs_warn_dup.cold+0x17/0x24
[ 105.861484] [ T1842] sysfs_create_dir_ns+0x1fc/0x270
[ 105.861490] [ T1842] ? __pfx_sysfs_create_dir_ns+0x10/0x10
[ 105.861495] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 105.861499] [ T1842] ? kasan_save_track+0x14/0x30
[ 105.861502] [ T1842] ? kfree+0x1d6/0x620
[ 105.861506] [ T1842] kobject_add_internal+0x26f/0x800
[ 105.861511] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 105.861514] [ T1842] kobject_add+0x139/0x1a0
[ 105.861517] [ T1842] ? __blk_mq_unfreeze_queue+0x24/0x1a0
[ 105.861521] [ T1842] ? __pfx_kobject_add+0x10/0x10
[ 105.861526] [ T1842] ? __mutex_unlock_slowpath+0x15d/0x860
[ 105.861528] [ T1842] ? do_raw_spin_lock+0x128/0x270
[ 105.861532] [ T1842] ? __mutex_lock+0x2bc/0x25a0
[ 105.861535] [ T1842] elevator_change_done+0x26f/0x690
[ 105.861540] [ T1842] ? __pfx_elevator_change_done+0x10/0x10
[ 105.861543] [ T1842] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 105.861549] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 105.861552] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 105.861555] [ T1842] elevator_change+0x283/0x4f0
[ 105.861559] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 105.861562] [ T1842] elv_iosched_store+0x30c/0x3a0
[ 105.861566] [ T1842] ? __pfx_elv_iosched_store+0x10/0x10
[ 105.861569] [ T1842] ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 105.861575] [ T1842] ? lock_acquire+0x126/0x140
[ 105.861579] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 105.861582] [ T1842] queue_attr_store+0x23f/0x360
[ 105.861586] [ T1842] ? __mutex_lock+0x1536/0x25a0
[ 105.861589] [ T1842] ? __pfx_queue_attr_store+0x10/0x10
[ 105.861592] [ T1842] ? lock_release+0xfa/0x120
[ 105.861595] [ T1842] ? __pfx___mutex_lock+0x10/0x10
[ 105.861599] [ T1842] ? __pfx__copy_from_iter+0x10/0x10
[ 105.861603] [ T1842] ? lock_acquire+0x126/0x140
[ 105.861606] [ T1842] ? lock_acquire+0x126/0x140
[ 105.861610] [ T1842] ? lock_release+0xfa/0x120
[ 105.861613] [ T1842] ? sysfs_file_kobj+0xb9/0x1b0
[ 105.861617] [ T1842] ? sysfs_kf_write+0x65/0x170
[ 105.861621] [ T1842] ? __pfx_sysfs_kf_write+0x10/0x10
[ 105.861623] [ T1842] kernfs_fop_write_iter+0x3da/0x5e0
[ 105.861627] [ T1842] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ 105.861630] [ T1842] vfs_write+0x524/0x1010
[ 105.861634] [ T1842] ? lock_release+0xfa/0x120
[ 105.861637] [ T1842] ? __pfx_vfs_write+0x10/0x10
[ 105.861639] [ T1842] ? wp_page_reuse+0x160/0x1e0
[ 105.861644] [ T1842] ? do_wp_page+0x57e/0xf40
[ 105.861649] [ T1842] ? __pfx_handle_pte_fault+0x10/0x10
[ 105.861653] [ T1842] ksys_write+0xff/0x200
[ 105.861656] [ T1842] ? __pfx_ksys_write+0x10/0x10
[ 105.861659] [ T1842] ? __handle_mm_fault+0xa02/0xef0
[ 105.861663] [ T1842] do_syscall_64+0xf4/0x660
[ 105.861667] [ T1842] ? __pfx___css_rstat_updated+0x10/0x10
[ 105.861674] [ T1842] ? count_memcg_events+0x37f/0x480
[ 105.861679] [ T1842] ? lock_release+0xfa/0x120
[ 105.861683] [ T1842] ? rcu_read_unlock+0x1c/0x60
[ 105.861685] [ T1842] ? handle_mm_fault+0x4d1/0x7d0
[ 105.861689] [ T1842] ? do_user_addr_fault+0x15d/0xed0
[ 105.861694] [ T1842] ? lock_release+0xfa/0x120
[ 105.861698] [ T1842] ? do_user_addr_fault+0x811/0xed0
[ 105.861701] [ T1842] ? irqentry_exit+0xb0/0x810
[ 105.861704] [ T1842] ? do_syscall_64+0x34/0x660
[ 105.861707] [ T1842] ? trace_hardirqs_on+0x19/0x1a0
[ 105.861710] [ T1842] ? irqentry_exit+0xb5/0x810
[ 105.861712] [ T1842] ? do_syscall_64+0xab/0x660
[ 105.861716] [ T1842] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 105.861719] [ T1842] RIP: 0033:0x7f96f4878bbe
[ 105.861722] [ T1842] Code: 4d 89 d8 e8 34 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
[ 105.861725] [ T1842] RSP: 002b:00007ffcb76ebbb0 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 105.861729] [ T1842] RAX: ffffffffffffffda RBX: 00007f96f49f45c0 RCX: 00007f96f4878bbe
[ 105.861732] [ T1842] RDX: 0000000000000006 RSI: 0000562ec532aa50 RDI: 0000000000000001
[ 105.861734] [ T1842] RBP: 00007ffcb76ebbc0 R08: 0000000000000000 R09: 0000000000000000
[ 105.861735] [ T1842] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
[ 105.861737] [ T1842] R13: 0000000000000006 R14: 0000562ec532aa50 R15: 0000562ec53972c0
[ 105.861742] [ T1842] </TASK>
[ 105.861748] [ T1842] kobject: kobject_add_internal failed for iosched with -EEXIST, don't try to register things with the same name in the same directory.
[4] dmesg during the sysytem boot
...
[ 14.387131] [ T117] ata7.00: Features: HIPM DIPM NCQ-sndrcv NCQ-prio
[ 14.387200] [ T129] sd 4:0:0:0: [sda] 976773168 512-byte logical blocks: (500 GB/466 GiB)
[ 14.387319] [ T129] sd 4:0:0:0: [sda] Write Protect is off
[ 14.387370] [ T129] sd 4:0:0:0: [sda] Mode Sense: 00 3a 00 00
[ 14.387492] [ T129] sd 4:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 14.387696] [ T129] sd 4:0:0:0: [sda] Preferred minimum I/O size 512 bytes
[ 14.391829] [ T1] usb usb4: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[ 14.391835] [ T1] usb usb4: Product: xHCI Host Controller
[ 14.391837] [ T1] usb usb4: Manufacturer: Linux 7.1.0-kts+ xhci-hcd
[ 14.411827] [ T117] ata7.00: configured for UDMA/133
[ 14.417307] [ T1] usb usb4: SerialNumber: 0000:00:14.0
[ 14.417647] [ T129] ------------[ cut here ]------------
[ 14.417668] [ T129] WARNING: block/blk-mq-debugfs.c:621 at debugfs_create_files+0x162/0x210, CPU#7: kworker/u32:11/129
[ 14.417681] [ T129] Modules linked in:
[ 14.417694] [ T129] CPU: 7 UID: 0 PID: 129 Comm: kworker/u32:11 Not tainted 7.1.0-kts+ #57 PREEMPT(lazy)
[ 14.417698] [ T129] Hardware name: Supermicro Super Server/X10SRL-F, BIOS 2.0 12/17/2015
[ 14.417701] [ T129] Workqueue: async async_run_entry_fn
[ 14.417708] [ T129] RIP: 0010:debugfs_create_files+0x162/0x210
[ 14.417713] [ T129] Code: 0f 85 aa 00 00 00 8b 15 e0 bc e1 03 85 d2 0f 84 0c ff ff ff 49 8d be 88 05 00 00 be ff ff ff ff e8 f3 ac a9 01 83 f8 01 75 02 <0f> 0b 48 b8 00 00 00 00 00 fc ff df 48 89 ea 83 e5 07 48 c1 ea 03
[ 14.417716] [ T129] RSP: 0000:ffff88811750f648 EFLAGS: 00010246
[ 14.417720] [ T129] RAX: 0000000000000001 RBX: ffffffffaaffa7e0 RCX: 0000000000000000
[ 14.417723] [ T129] RDX: 0000000000000001 RSI: ffff888119603418 RDI: ffff888116521060
[ 14.417726] [ T129] RBP: ffffffffacf3cc24 R08: 0000000000000001 R09: ffffed10200b2365
[ 14.417729] [ T129] R10: ffffed10200b2366 R11: 0000000000000001 R12: ffff888100591a70
[ 14.417731] [ T129] R13: ffff888119602e90 R14: ffff888119602e90 R15: ffff888101ff5818
[ 14.417734] [ T129] FS: 0000000000000000(0000) GS:ffff8887b01c8000(0000) knlGS:0000000000000000
[ 14.417737] [ T129] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 14.417740] [ T129] CR2: 0000000000000000 CR3: 00000004f909c001 CR4: 00000000001706f0
[ 14.417743] [ T129] Call Trace:
[ 14.417745] [ T129] <TASK>
[ 14.417751] [ T129] blk_mq_sched_reg_debugfs+0x8d/0x1a0
[ 14.417761] [ T129] elevator_change_done+0x329/0x690
[ 14.417771] [ T129] ? __pfx_elevator_change_done+0x10/0x10
[ 14.417776] [ T129] ? __lock_release.isra.0+0x59/0x170
[ 14.417789] [ T129] elevator_change+0x283/0x4f0
[ 14.417798] [ T129] elevator_set_default+0x236/0x2e0
[ 14.417804] [ T129] ? __pfx_elevator_set_default+0x10/0x10
[ 14.417815] [ T129] ? disk_register_independent_access_ranges+0x24f/0x310
[ 14.417825] [ T129] blk_register_queue+0x412/0x5b0
[ 14.417837] [ T129] __add_disk+0x5fd/0xd50
[ 14.417843] [ T129] ? __pfx_do_raw_spin_lock+0x10/0x10
[ 14.417847] [ T129] ? find_held_lock+0x2b/0x80
[ 14.417853] [ T129] add_disk_fwnode+0x113/0x590
[ 14.417863] [ T129] sd_probe+0x8b5/0xf90
[ 14.417873] [ T129] call_driver_probe+0x64/0x1e0
[ 14.417880] [ T129] really_probe+0x194/0x740
[ 14.417889] [ T129] ? __pfx___device_attach_driver+0x10/0x10
[ 14.417893] [ T129] __driver_probe_device+0x1cb/0x400
[ 14.417900] [ T129] driver_probe_device+0x4a/0x120
[ 14.417906] [ T129] __device_attach_driver+0x156/0x2a0
[ 14.417913] [ T129] bus_for_each_drv+0x114/0x1a0
[ 14.417917] [ T129] ? mark_held_locks+0x40/0x70
[ 14.417922] [ T129] ? __pfx_bus_for_each_drv+0x10/0x10
[ 14.417927] [ T129] ? trace_hardirqs_on+0x19/0x1a0
[ 14.417933] [ T129] ? _raw_spin_unlock_irqrestore+0x44/0x60
[ 14.417942] [ T129] __device_attach_async_helper+0x19f/0x250
[ 14.417948] [ T129] ? __pfx___device_attach_async_helper+0x10/0x10
[ 14.417953] [ T129] ? seqcount_lockdep_reader_access+0x94/0xb0
[ 14.417961] [ T129] ? ktime_get+0x35/0x1b0
[ 14.417965] [ T129] ? ktime_get+0x35/0x1b0
[ 14.417972] [ T129] async_run_entry_fn+0x97/0x550
[ 14.417979] [ T129] process_one_work+0x8b7/0x1650
[ 14.417995] [ T129] ? __pfx_process_one_work+0x10/0x10
[ 14.418073] [ T129] ? lock_acquire.part.0+0xb8/0x230
[ 14.418083] [ T129] ? lock_is_held_type+0x9a/0x110
[ 14.418096] [ T129] worker_thread+0x60a/0xff0
[ 14.418110] [ T129] ? __pfx_worker_thread+0x10/0x10
[ 14.418114] [ T129] kthread+0x35d/0x460
[ 14.418119] [ T129] ? _raw_spin_unlock_irq+0x28/0x50
[ 14.418124] [ T129] ? __pfx_kthread+0x10/0x10
[ 14.418130] [ T129] ret_from_fork+0x55b/0x850
[ 14.418137] [ T129] ? __pfx_ret_from_fork+0x10/0x10
[ 14.418144] [ T129] ? __switch_to+0x474/0xd80
[ 14.418148] [ T129] ? __switch_to_asm+0x39/0x70
[ 14.418153] [ T129] ? __switch_to_asm+0x33/0x70
[ 14.418157] [ T129] ? __pfx_kthread+0x10/0x10
[ 14.418163] [ T129] ret_from_fork_asm+0x1a/0x30
[ 14.418179] [ T129] </TASK>
[ 14.418181] [ T129] irq event stamp: 4509
[ 14.418183] [ T129] hardirqs last enabled at (4515): [<ffffffffa7dd11d5>] console_trylock_spinning+0x1c5/0x1f0
[ 14.418188] [ T129] hardirqs last disabled at (4520): [<ffffffffa7dd1188>] console_trylock_spinning+0x178/0x1f0
[ 14.418193] [ T129] softirqs last enabled at (4028): [<ffffffffa7bc5b91>] handle_softirqs+0x5c1/0x8b0
[ 14.418198] [ T129] softirqs last disabled at (4023): [<ffffffffa7bc5fe2>] __irq_exit_rcu+0x152/0x280
[ 14.418203] [ T129] ---[ end trace 0000000000000000 ]---
[ 14.445938] [ T84] usb 1-1: New USB device found, idVendor=8087, idProduct=8002, bcdDevice= 0.05
[ 14.456687] [ T1] hub 4-0:1.0: USB hub found
[ 14.460399] [ T84] usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[ 14.468534] [ T1] hub 4-0:1.0: 6 ports detected
[ 14.477755] [ T129] sda: sda1 sda2 sda3
[ 14.478903] [ T84] hub 1-1:1.0: USB hub found
[ 14.479235] [ T84] hub 1-1:1.0: 8 ports detected
[ 14.500815] [ T14] Freeing initrd memory: 58856K
[ 14.511419] [ T129] sd 4:0:0:0: [sda] Attached SCSI disk
[ 14.591054] [ T1] usbcore: registered new interface driver usbserial_generic
[ 14.624054] [ T133] usb 3-1: new high-speed USB device number 2 using ehci-pci
[ 14.630659] [ T1] usbserial: USB Serial support registered for generic
[ 14.642060] [ T82] usb 2-12: new high-speed USB device number 2 using xhci_hcd
[ 14.647384] [ T1] i8042: PNP: No PS/2 controller found.
[ 14.783710] [ T82] usb 2-12: New USB device found, idVendor=0557, idProduct=7000, bcdDevice= 0.00
[ 14.788031] [ T1] mousedev: PS/2 mouse device common for all mice
[ 14.791695] [ T82] usb 2-12: New USB device strings: Mfr=0, Product=0, SerialNumber=0
[ 14.798401] [ T1] rtc_cmos PNP0B00:00: RTC can wake from S4
[ 14.806361] [ T82] hub 2-12:1.0: USB hub found
[ 14.809380] [ T1] rtc_cmos PNP0B00:00: registered as rtc0
[ 14.811778] [ T82] hub 2-12:1.0: 4 ports detected
[ 14.816589] [ T1] rtc_cmos PNP0B00:00: setting system clock to 2026-06-24T11:36:20 UTC (1782300980)
[ 14.875529] [ T133] usb 3-1: New USB device found, idVendor=8087, idProduct=800a, bcdDevice=
...
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] block: serialize elevator changes for the same queue using a writer lock
2026-06-24 11:48 ` Shin'ichiro Kawasaki
@ 2026-06-24 15:09 ` Ming Lei
0 siblings, 0 replies; 6+ messages in thread
From: Ming Lei @ 2026-06-24 15:09 UTC (permalink / raw)
To: Shin'ichiro Kawasaki; +Cc: linux-block, Jens Axboe, Nilay Shroff
On Wed, Jun 24, 2026 at 08:48:16PM +0900, Shin'ichiro Kawasaki wrote:
> On Jun 24, 2026 / 04:44, Ming Lei wrote:
> > On Tue, Jun 23, 2026 at 10:32:38AM +0900, Shin'ichiro Kawasaki wrote:
> [...]
> > > Please refer to [1] for details of the failure. Also, I created a
> > > blktests test case that recreates the hang [2], which I used to test the
> > > fix.
> > >
> > > * Changes from RFC v1
> > > - Instead of adding a new mutex to struct request_queue, replace the
> > > reader lock on update_nr_hwq_lock with the writer lock in
> > > elv_iosched_store().
> > >
> > > [1] https://lore.kernel.org/linux-block/20260611074200.474676-1-shinichiro.kawasaki@wdc.com/
> > > [2] https://github.com/kawasaki/blktests/commit/8e80b3ccc0bbbe3f209d00eacd138d020de97fc6
> > >
> > > block/elevator.c | 4 ++--
> > > 1 file changed, 2 insertions(+), 2 deletions(-)
> [...]
> > I feel this is still abuse of the above lock, which serves writer vs
> > reader wrt. updating hw queue.
> >
> > How about the following fix?
>
> (snip)
>
> Thank you for the idea. I applied the suggested fix on top of the v7.1 kernel,
> and ran the test case that does the concurrent write to the sysfs sched file
> [2]. Unfortunately, the test case hung. Before the hang, the kernel reported
> WARNs in sysfs_create_dir_ns() [3]. KASAN slab-use-after-free was observed also.
> I also noticed that another WARN was observed during boot [4].
Looks this change isn't enough, and it is a bit hard to deal with the
two-stage switch by re-lock, and it may require sched debugfs & elevator queue
reg/unreg refactor.
Let's fix with your simpler way first.
Thanks,
Ming
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2] block: serialize elevator changes for the same queue using a writer lock
2026-06-23 1:32 [PATCH v2] block: serialize elevator changes for the same queue using a writer lock Shin'ichiro Kawasaki
2026-06-23 5:29 ` Nilay Shroff
2026-06-24 9:44 ` Ming Lei
@ 2026-06-24 15:12 ` Ming Lei
2 siblings, 0 replies; 6+ messages in thread
From: Ming Lei @ 2026-06-24 15:12 UTC (permalink / raw)
To: Shin'ichiro Kawasaki; +Cc: linux-block, Jens Axboe, Nilay Shroff
On Tue, Jun 23, 2026 at 10:32:38AM +0900, Shin'ichiro Kawasaki wrote:
> When elevator_change() is called concurrently for the same queue, the
> elevator_change_done() function runs concurrently as well. This function
> adds or deletes kobjects for the debugfs entry of the queue. Then the
> concurrent calls cause memory corruption of the kobjects and result in a
> process hang. The core part of the elevator switch is protected by queue
> freeze and q->elevator_lock. However, since the commit 559dc11143eb
> ("block: move elv_register[unregister]_queue out of elevator_lock"), the
> elevator_change_done() is not serialized. Hence the memory corruption
> and the hang.
>
> The failures are observed when udev-worker writes to a sysfs
> queue/scheduler attribute file while the blktests test case block/005
> writes to the same attribute file. The failure also can be recreated by
> running two processes that write to the same queue/scheduler file
> concurrently. The failure is observed since another commit 370ac285f23a
> ("block: avoid cpu_hotplug_lock depedency on freeze_lock"). This commit
> changed the behavior of queue freeze and it unveiled the failure.
>
> Fix the failure by changing elv_iosched_store() to acquire
> update_nr_hwq_lock as the writer lock instead of the reader lock. This
> serializes the whole elevator switch steps, including the
> elevator_change_done() call.
>
> Fixes: 559dc11143eb ("block: move elv_register[unregister]_queue out of elevator_lock")
> Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
> ---
> I observed that the blktests test case block/005 hung on a specific
> server hardware using a specific HDD as a block device. During the test
> case run, the kernel reported KASAN null-ptr-deref and slab-use-after-
> free errors. The failure happened when a sysfs queue/scheduler attribute
> file is written concurrently. I reported the failure and shared a
> candidate fix patch as RFC [1]. Based on the comments and discussion on
> the RFC patch, I propose this v2 patch that avoids introducing a new
> lock. My thanks go to Ming and Nilay for the discussion.
>
> Please refer to [1] for details of the failure. Also, I created a
> blktests test case that recreates the hang [2], which I used to test the
> fix.
>
> * Changes from RFC v1
> - Instead of adding a new mutex to struct request_queue, replace the
> reader lock on update_nr_hwq_lock with the writer lock in
> elv_iosched_store().
>
> [1] https://lore.kernel.org/linux-block/20260611074200.474676-1-shinichiro.kawasaki@wdc.com/
> [2] https://github.com/kawasaki/blktests/commit/8e80b3ccc0bbbe3f209d00eacd138d020de97fc6
>
> block/elevator.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/block/elevator.c b/block/elevator.c
> index 3bcd37c2aa34..b03185a217ff 100644
> --- a/block/elevator.c
> +++ b/block/elevator.c
> @@ -813,7 +813,7 @@ ssize_t elv_iosched_store(struct gendisk *disk, const char *buf,
> * update_nr_hwq_lock -> kn->active (via del_gendisk -> kobject_del)
> * kn->active -> update_nr_hwq_lock (via this sysfs write path)
> */
> - if (!down_read_trylock(&set->update_nr_hwq_lock)) {
> + if (!down_write_trylock(&set->update_nr_hwq_lock)) {
I'd suggest to document why using write_trylock above, such as serializing
2-stage elevator switch, anyway this patch looks good as bug fix:
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Thanks,
Ming
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2026-06-24 15:13 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-06-23 1:32 [PATCH v2] block: serialize elevator changes for the same queue using a writer lock Shin'ichiro Kawasaki
2026-06-23 5:29 ` Nilay Shroff
2026-06-24 9:44 ` Ming Lei
2026-06-24 11:48 ` Shin'ichiro Kawasaki
2026-06-24 15:09 ` Ming Lei
2026-06-24 15:12 ` Ming Lei
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