* [syzbot] [bcachefs?] INFO: task hung in bch2_page_fault
@ 2024-12-13 22:41 syzbot
2025-06-17 16:52 ` syzbot
2025-06-21 1:50 ` syzbot
0 siblings, 2 replies; 4+ messages in thread
From: syzbot @ 2024-12-13 22:41 UTC (permalink / raw)
To: kent.overstreet, linux-bcachefs, linux-kernel, syzkaller-bugs
Hello,
syzbot found the following issue on:
HEAD commit: f932fb9b4074 Merge tag 'v6.13-rc2-ksmbd-server-fixes' of g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=106aea0f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=c7c9f223bfe8924e
dashboard link: https://syzkaller.appspot.com/bug?extid=32415e0466b02533303c
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f906447f0c03/disk-f932fb9b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0ddfd52ea0e6/vmlinux-f932fb9b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4c5a34e2dbda/bzImage-f932fb9b.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+32415e0466b02533303c@syzkaller.appspotmail.com
INFO: task syz.3.161:7157 blocked for more than 143 seconds.
Not tainted 6.13.0-rc2-syzkaller-00159-gf932fb9b4074 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.161 state:D stack:24320 pid:7157 tgid:7117 ppid:5827 flags:0x00000004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5369 [inline]
__schedule+0x17fb/0x4be0 kernel/sched/core.c:6756
__schedule_loop kernel/sched/core.c:6833 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6848
__bch2_two_state_lock+0x229/0x2c0 fs/bcachefs/two_state_shared_lock.c:7
bch2_two_state_lock fs/bcachefs/two_state_shared_lock.h:55 [inline]
bch2_page_fault+0x31f/0x960 fs/bcachefs/fs-io-pagecache.c:592
__do_fault+0x135/0x390 mm/memory.c:4907
do_read_fault mm/memory.c:5322 [inline]
do_fault mm/memory.c:5456 [inline]
do_pte_missing mm/memory.c:3979 [inline]
handle_pte_fault+0x39eb/0x5ed0 mm/memory.c:5801
__handle_mm_fault mm/memory.c:5944 [inline]
handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6112
do_user_addr_fault arch/x86/mm/fault.c:1389 [inline]
handle_page_fault arch/x86/mm/fault.c:1481 [inline]
exc_page_fault+0x2b9/0x8b0 arch/x86/mm/fault.c:1539
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:fault_in_readable+0x173/0x2d0 mm/gup.c:2244
Code: 00 fc ff df 4c 89 e8 4f 8d ac 25 ff 0f 00 00 49 81 e5 00 f0 ff ff 49 39 c5 72 7a e8 e7 da b7 ff 4c 39 eb 74 7d 4c 89 64 24 08 <44> 8a 23 43 0f b6 04 3e 84 c0 75 18 44 88 64 24 40 48 81 c3 00 10
RSP: 0018:ffffc90003cf7920 EFLAGS: 00050287
RAX: ffffffff81e78309 RBX: 0000000020001000 RCX: 0000000000080000
RDX: ffffc9000f05a000 RSI: 0000000000000042 RDI: 0000000000000043
RBP: ffffc90003cf79d8 R08: ffffffff81e7829c R09: ffffffff84b7a909
R10: 0000000000000002 R11: ffff88802bd40000 R12: 000000000000fdef
R13: 0000000020010000 R14: 1ffff9200079ef2c R15: dffffc0000000000
fault_in_iov_iter_readable+0x229/0x280 lib/iov_iter.c:94
bch2_buffered_write fs/bcachefs/fs-io-buffered.c:983 [inline]
bch2_write_iter+0x528/0x2c10 fs/bcachefs/fs-io-buffered.c:1054
new_sync_write fs/read_write.c:586 [inline]
vfs_write+0xaeb/0xd30 fs/read_write.c:679
ksys_pwrite64 fs/read_write.c:786 [inline]
__do_sys_pwrite64 fs/read_write.c:794 [inline]
__se_sys_pwrite64 fs/read_write.c:791 [inline]
__x64_sys_pwrite64+0x1ac/0x240 fs/read_write.c:791
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8345b85d19
RSP: 002b:00007f834692e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007f8345d76080 RCX: 00007f8345b85d19
RDX: 000000000000fdef RSI: 0000000020000140 RDI: 0000000000000008
RBP: 00007f8345c01a20 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000fecc R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f8345d76080 R15: 00007ffdec473828
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744
1 lock held by dhcpcd/5486:
#0: ffff8880b863e758 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:598
2 locks held by getty/5581:
#0: ffff88814dac10a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
5 locks held by syz.3.161/7118:
#0: ffff88807e0d2420 (sb_writers#27){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:515
#1: ffff88805603a6c8 (&sb->s_type->i_mutex_key#32){++++}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline]
#1: ffff88805603a6c8 (&sb->s_type->i_mutex_key#32){++++}-{4:4}, at: do_truncate+0x20c/0x310 fs/open.c:63
#2: ffff888069880a38 (&c->snapshot_create_lock){.+.+}-{4:4}, at: bch2_truncate+0x166/0x2d0 fs/bcachefs/io_misc.c:292
#3: ffff888069884398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline]
#3: ffff888069884398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline]
#3: ffff888069884398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7e1/0xd30 fs/bcachefs/btree_iter.c:3228
#4: ffff8880698a66d0 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x682/0x14e0 fs/bcachefs/btree_update_interior.c:1197
3 locks held by syz.3.161/7157:
#0: ffff88807e0d2420 (sb_writers#27){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2964 [inline]
#0: ffff88807e0d2420 (sb_writers#27){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:675
#1: ffff8880563497c8 (&sb->s_type->i_mutex_key#32){++++}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline]
#1: ffff8880563497c8 (&sb->s_type->i_mutex_key#32){++++}-{4:4}, at: bch2_write_iter+0x13a/0x2c10 fs/bcachefs/fs-io-buffered.c:1040
#2: ffff8880119d60e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_trylock include/linux/mmap_lock.h:163 [inline]
#2: ffff8880119d60e0 (&mm->mmap_lock){++++}-{4:4}, at: get_mmap_lock_carefully mm/memory.c:6149 [inline]
#2: ffff8880119d60e0 (&mm->mmap_lock){++++}-{4:4}, at: lock_mm_and_find_vma+0x32/0x2f0 mm/memory.c:6209
2 locks held by dhcpcd/11053:
#0: ffff88807fc3e258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1617 [inline]
#0: ffff88807fc3e258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcb0 net/packet/af_packet.c:3267
#1: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
#1: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976
2 locks held by dhcpcd/11054:
#0: ffff88807fa12258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1617 [inline]
#0: ffff88807fa12258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcb0 net/packet/af_packet.c:3267
#1: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline]
#1: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc2-syzkaller-00159-gf932fb9b4074 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline]
watchdog+0xff6/0x1040 kernel/hung_task.c:397
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 3548 Comm: kworker/u8:7 Not tainted 6.13.0-rc2-syzkaller-00159-gf932fb9b4074 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/25/2024
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:clear_page_erms+0xb/0x20 arch/x86/lib/clear_page_64.S:50
Code: 48 8d 7f 40 75 d9 90 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa b9 00 10 00 00 31 c0 <f3> aa c3 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90
RSP: 0018:ffffc9000d327390 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000dc0
RDX: ffff888034b0c000 RSI: 0000000000000004 RDI: ffff888034b0c240
RBP: 0000000000000004 R08: ffffea0000d2c237 R09: 0000000000000000
R10: ffffed1006961000 R11: fffff940001a5847 R12: 0000000000000001
R13: 0000000000000008 R14: ffffea0000d2c200 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005643e844f680 CR3: 000000000e736000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
clear_page arch/x86/include/asm/page_64.h:54 [inline]
clear_highpage_kasan_tagged include/linux/highmem.h:242 [inline]
kernel_init_pages mm/page_alloc.c:1040 [inline]
post_alloc_hook+0xf8/0x230 mm/page_alloc.c:1554
prep_new_page mm/page_alloc.c:1564 [inline]
get_page_from_freelist+0x3651/0x37a0 mm/page_alloc.c:3474
__alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751
alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2269
alloc_slab_page+0x6a/0x110 mm/slub.c:2408
allocate_slab+0x5a/0x2b0 mm/slub.c:2574
new_slab mm/slub.c:2627 [inline]
___slab_alloc+0xc27/0x14a0 mm/slub.c:3815
__slab_alloc+0x58/0xa0 mm/slub.c:3905
__slab_alloc_node mm/slub.c:3980 [inline]
slab_alloc_node mm/slub.c:4141 [inline]
__do_kmalloc_node mm/slub.c:4282 [inline]
__kmalloc_node_track_caller_noprof+0x2e9/0x4c0 mm/slub.c:4302
kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:609
__alloc_skb+0x1f3/0x440 net/core/skbuff.c:678
alloc_skb include/linux/skbuff.h:1323 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
nsim_dev_trap_report_work+0x261/0xb50 drivers/net/netdevsim/dev.c:851
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
---
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If the report is already addressed, let syzbot know by replying with:
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If you want to overwrite report's subsystems, reply with:
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If the report is a duplicate of another one, reply with:
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If you want to undo deduplication, reply with:
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^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [syzbot] [bcachefs?] INFO: task hung in bch2_page_fault
2024-12-13 22:41 [syzbot] [bcachefs?] INFO: task hung in bch2_page_fault syzbot
@ 2025-06-17 16:52 ` syzbot
2025-08-08 5:40 ` Alan Huang
2025-06-21 1:50 ` syzbot
1 sibling, 1 reply; 4+ messages in thread
From: syzbot @ 2025-06-17 16:52 UTC (permalink / raw)
To: kent.overstreet, linux-bcachefs, linux-kernel, syzkaller-bugs
syzbot has found a reproducer for the following issue on:
HEAD commit: 9afe652958c3 Merge tag 'x86_urgent_for_6.16-rc3' of git://..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11665e82580000
kernel config: https://syzkaller.appspot.com/x/.config?x=6a237c32900fc479
dashboard link: https://syzkaller.appspot.com/bug?extid=32415e0466b02533303c
compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=130d790c580000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ca235ca5eaeb/disk-9afe6529.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/ce4a880751fe/vmlinux-9afe6529.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a7c651092242/bzImage-9afe6529.xz
mounted in repro #1: https://storage.googleapis.com/syzbot-assets/eae8507e16f4/mount_0.gz
mounted in repro #2: https://storage.googleapis.com/syzbot-assets/9464fbe325ac/mount_4.gz
mounted in repro #3: https://storage.googleapis.com/syzbot-assets/5eac8f4c23dc/mount_6.gz
fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=16665e82580000)
mounted in repro #4: https://storage.googleapis.com/syzbot-assets/6901c045125d/mount_15.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=137355d4580000)
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+32415e0466b02533303c@syzkaller.appspotmail.com
INFO: task syz.4.25:6211 blocked for more than 143 seconds.
Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.25 state:D stack:24616 pid:6211 tgid:6211 ppid:5990 task_flags:0x400040 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
__bch2_two_state_lock+0x1ea/0x370 fs/bcachefs/two_state_shared_lock.c:7
bch2_two_state_lock fs/bcachefs/two_state_shared_lock.h:55 [inline]
bch2_page_fault+0x2f6/0x7a0 fs/bcachefs/fs-io-pagecache.c:592
__do_fault+0x138/0x390 mm/memory.c:5189
do_shared_fault mm/memory.c:5674 [inline]
do_fault mm/memory.c:5748 [inline]
do_pte_missing mm/memory.c:4251 [inline]
handle_pte_fault mm/memory.c:6089 [inline]
__handle_mm_fault+0x198b/0x5620 mm/memory.c:6232
handle_mm_fault+0x2d5/0x7f0 mm/memory.c:6401
do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7efe53d567c7
RSP: 002b:00007ffd198848c8 EFLAGS: 00010203
RAX: 0000200000002500 RBX: 0000000000000004 RCX: 0000200000002500
RDX: 00002000000036e8 RSI: 00007efe53825cad RDI: 0000200000002520
RBP: 00007efe53fb7ba0 R08: 0000000000000000 R09: 0000000000000049
R10: 0000000000000000 R11: 0000000000000001 R12: 00007efe53fb616c
R13: 00007efe53fb6160 R14: fffffffffffffffe R15: 00007ffd198849e0
</TASK>
INFO: task syz.4.25:6212 blocked for more than 144 seconds.
Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.25 state:D stack:17736 pid:6212 tgid:6211 ppid:5990 task_flags:0x440140 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
__bch2_two_state_lock+0x1ea/0x370 fs/bcachefs/two_state_shared_lock.c:7
bch2_two_state_lock fs/bcachefs/two_state_shared_lock.h:55 [inline]
bch2_readahead+0x94f/0x1100 fs/bcachefs/fs-io-buffered.c:296
read_pages+0x17a/0x580 mm/readahead.c:160
page_cache_ra_order+0xa24/0xc70 mm/readahead.c:515
filemap_readahead mm/filemap.c:2571 [inline]
filemap_get_pages+0xb22/0x1ea0 mm/filemap.c:2616
filemap_splice_read+0x4fc/0xbc0 mm/filemap.c:2990
do_splice_read fs/splice.c:979 [inline]
splice_direct_to_actor+0x4a6/0xcc0 fs/splice.c:1083
do_splice_direct_actor fs/splice.c:1201 [inline]
do_splice_direct+0x181/0x270 fs/splice.c:1227
vfs_copy_file_range+0xabc/0x1310 fs/read_write.c:1627
__do_sys_copy_file_range fs/read_write.c:1677 [inline]
__se_sys_copy_file_range+0x2fb/0x470 fs/read_write.c:1644
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efe53d8e929
RSP: 002b:00007efe54b68038 EFLAGS: 00000246 ORIG_RAX: 0000000000000146
RAX: ffffffffffffffda RBX: 00007efe53fb5fa0 RCX: 00007efe53d8e929
RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 00007efe53e10b39 R08: 0000000000400000 R09: 0000000000000000
R10: 00002000000000c0 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007efe53fb5fa0 R15: 00007ffd19884768
</TASK>
INFO: task syz.4.25:6264 blocked for more than 145 seconds.
Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.25 state:D stack:25976 pid:6264 tgid:6211 ppid:5990 task_flags:0x400040 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
io_schedule+0x81/0xe0 kernel/sched/core.c:7723
folio_wait_bit_common+0x6b0/0xb90 mm/filemap.c:1317
folio_lock include/linux/pagemap.h:1114 [inline]
invalidate_inode_pages2_range+0x557/0xa80 mm/truncate.c:690
bch2_write_invalidate_inode_pages_range+0xc5/0x110 fs/bcachefs/fs-io-pagecache.c:68
bch2_direct_write+0x2a62/0x2ce0 fs/bcachefs/fs-io-direct.c:662
bch2_write_iter+0x18f/0x2b90 fs/bcachefs/fs-io-buffered.c:1064
do_iter_readv_writev+0x56b/0x7f0 fs/read_write.c:-1
vfs_writev+0x31a/0x960 fs/read_write.c:1057
do_pwritev fs/read_write.c:1153 [inline]
__do_sys_pwritev2 fs/read_write.c:1211 [inline]
__se_sys_pwritev2+0x179/0x290 fs/read_write.c:1202
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efe53d8e929
RSP: 002b:00007efe54b47038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007efe53fb6080 RCX: 00007efe53d8e929
RDX: 0000000000000001 RSI: 0000200000000240 RDI: 0000000000000005
RBP: 00007efe53e10b39 R08: 0000000000000000 R09: 0000000000000003
R10: 0000000000007000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007efe53fb6080 R15: 00007ffd19884768
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
3 locks held by kworker/0:2/1214:
2 locks held by getty/5584:
#0: ffff88803543a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by syz-executor/5975:
#0: ffff88805c16a0e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88805c16a0e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88805c16a0e0 (&type->s_umount_key#54){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffff8880ae700278 (&c->state_lock){+.+.}-{4:4}, at: __bch2_fs_stop+0xf8/0x900 fs/bcachefs/super.c:677
#2: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#2: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
3 locks held by kworker/0:4/5981:
1 lock held by syz.4.25/6211:
#0: ffff88805a860a88 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x2d9/0x1390 arch/x86/mm/fault.c:1327
1 lock held by syz.4.25/6212:
#0: ffff8880564d1218 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#0: ffff8880564d1218 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: page_cache_ra_order+0x445/0xc70 mm/readahead.c:491
1 lock held by syz.4.25/6264:
#0: ffff88802457a428 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
#0: ffff88802457a428 (sb_writers#13){.+.+}-{0:0}, at: vfs_writev+0x288/0x960 fs/read_write.c:1055
1 lock held by syz.3.63/6745:
#0: ffff888047965948 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x2d9/0x1390 arch/x86/mm/fault.c:1327
1 lock held by syz.3.63/6746:
#0: ffff888056663810 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#0: ffff888056663810 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: page_cache_ra_order+0x445/0xc70 mm/readahead.c:491
1 lock held by syz.3.63/6801:
#0: ffff88802a336428 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
#0: ffff88802a336428 (sb_writers#13){.+.+}-{0:0}, at: vfs_writev+0x288/0x960 fs/read_write.c:1055
3 locks held by syz-executor/6934:
#0: ffff88807577a0e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88807577a0e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88807577a0e0 (&type->s_umount_key#54){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffff8880b3780278 (&c->state_lock){+.+.}-{4:4}, at: __bch2_fs_stop+0xf8/0x900 fs/bcachefs/super.c:677
#2: ffff8880b3780918 (&c->sb_lock){+.+.}-{4:4}, at: bch2_fs_mark_clean+0x44/0x380 fs/bcachefs/sb-clean.c:292
1 lock held by syz.5.115/7450:
#0: ffff888054ecf808 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x2d9/0x1390 arch/x86/mm/fault.c:1327
1 lock held by syz.5.115/7451:
#0: ffff8880564e5e08 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#0: ffff8880564e5e08 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: page_cache_ra_order+0x445/0xc70 mm/readahead.c:491
1 lock held by syz.5.115/7498:
#0: ffff888030e24428 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
#0: ffff888030e24428 (sb_writers#13){.+.+}-{0:0}, at: vfs_writev+0x288/0x960 fs/read_write.c:1055
1 lock held by syz.7.130/7767:
#0: ffff888048694bc8 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x2d9/0x1390 arch/x86/mm/fault.c:1327
1 lock held by syz.7.130/7768:
#0: ffff8880564e3fa8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
#0: ffff8880564e3fa8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: page_cache_ra_order+0x445/0xc70 mm/readahead.c:491
1 lock held by syz.7.130/7816:
#0: ffff888032802428 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
#0: ffff888032802428 (sb_writers#13){.+.+}-{0:0}, at: vfs_writev+0x288/0x960 fs/read_write.c:1055
3 locks held by syz-executor/7973:
#0: ffff88807b4300e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88807b4300e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88807b4300e0 (&type->s_umount_key#54){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffff888097700278 (&c->state_lock){+.+.}-{4:4}, at: __bch2_fs_stop+0xf8/0x900 fs/bcachefs/super.c:677
#2: ffff888097700918 (&c->sb_lock){+.+.}-{4:4}, at: bch2_fs_mark_clean+0x44/0x380 fs/bcachefs/sb-clean.c:292
2 locks held by syz.2.173/8269:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:100 [inline]
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
RIP: 0010:unwind_next_frame+0x12e3/0x2390 arch/x86/kernel/unwind_orc.c:494
Code: 18 48 8b 10 48 c7 c7 00 3a 88 8b 89 de e8 55 de b4 ff e9 43 06 00 00 49 89 d5 48 89 d5 48 89 d8 48 29 e8 48 89 c1 48 c1 f9 02 <48> c1 e8 3f 48 01 c8 48 83 e0 fe 4c 8d 3c 45 00 00 00 00 49 01 ef
RSP: 0018:ffffc900001d7398 EFLAGS: 00000202
RAX: 0000000000000004 RBX: ffffffff8fb37924 RCX: 0000000000000001
RDX: ffffffff8fb37904 RSI: ffffffff902e9bf0 RDI: ffffffff8be1b7a0
RBP: ffffffff8fb37920 R08: 0000000000000009 R09: ffffffff81729af5
R10: ffffc900001d74c8 R11: fffff5200003aea5 R12: ffffffff8172c397
R13: ffffffff8fb3791c R14: ffffc900001d74c8 R15: ffffffff8fb3791c
FS: 0000000000000000(0000) GS:ffff888125d85000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc7ecf3d000 CR3: 000000002fea8000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline]
slab_free_hook mm/slub.c:2381 [inline]
slab_free mm/slub.c:4643 [inline]
kfree+0x18e/0x440 mm/slub.c:4842
slab_free_after_rcu_debug+0x60/0x2a0 mm/slub.c:4680
rcu_do_batch kernel/rcu/tree.c:2576 [inline]
rcu_core+0xca8/0x1710 kernel/rcu/tree.c:2832
handle_softirqs+0x286/0x870 kernel/softirq.c:579
run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968
smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:164
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [syzbot] [bcachefs?] INFO: task hung in bch2_page_fault
2024-12-13 22:41 [syzbot] [bcachefs?] INFO: task hung in bch2_page_fault syzbot
2025-06-17 16:52 ` syzbot
@ 2025-06-21 1:50 ` syzbot
1 sibling, 0 replies; 4+ messages in thread
From: syzbot @ 2025-06-21 1:50 UTC (permalink / raw)
To: kent.overstreet, linux-bcachefs, linux-kernel, syzkaller-bugs
syzbot has bisected this issue to:
commit 8b1f46bff38f075b8d4071e7ac1edecb441fd53c
Author: Kent Overstreet <kent.overstreet@linux.dev>
Date: Sun Dec 29 00:57:04 2024 +0000
bcachefs: Dropped superblock write is no longer a fatal error
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=140d530c580000
start commit: 9afe652958c3 Merge tag 'x86_urgent_for_6.16-rc3' of git://..
git tree: upstream
final oops: https://syzkaller.appspot.com/x/report.txt?x=160d530c580000
console output: https://syzkaller.appspot.com/x/log.txt?x=120d530c580000
kernel config: https://syzkaller.appspot.com/x/.config?x=6a237c32900fc479
dashboard link: https://syzkaller.appspot.com/bug?extid=32415e0466b02533303c
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=130d790c580000
Reported-by: syzbot+32415e0466b02533303c@syzkaller.appspotmail.com
Fixes: 8b1f46bff38f ("bcachefs: Dropped superblock write is no longer a fatal error")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [syzbot] [bcachefs?] INFO: task hung in bch2_page_fault
2025-06-17 16:52 ` syzbot
@ 2025-08-08 5:40 ` Alan Huang
0 siblings, 0 replies; 4+ messages in thread
From: Alan Huang @ 2025-08-08 5:40 UTC (permalink / raw)
To: syzbot; +Cc: kent.overstreet, linux-bcachefs, linux-kernel, syzkaller-bugs
On Jun 18, 2025, at 00:52, syzbot <syzbot+32415e0466b02533303c@syzkaller.appspotmail.com> wrote:
>
> syzbot has found a reproducer for the following issue on:
>
> HEAD commit: 9afe652958c3 Merge tag 'x86_urgent_for_6.16-rc3' of git://..
> git tree: upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=11665e82580000
> kernel config: https://syzkaller.appspot.com/x/.config?x=6a237c32900fc479
> dashboard link: https://syzkaller.appspot.com/bug?extid=32415e0466b02533303c
> compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=130d790c580000
>
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/ca235ca5eaeb/disk-9afe6529.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/ce4a880751fe/vmlinux-9afe6529.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/a7c651092242/bzImage-9afe6529.xz
> mounted in repro #1: https://storage.googleapis.com/syzbot-assets/eae8507e16f4/mount_0.gz
> mounted in repro #2: https://storage.googleapis.com/syzbot-assets/9464fbe325ac/mount_4.gz
> mounted in repro #3: https://storage.googleapis.com/syzbot-assets/5eac8f4c23dc/mount_6.gz
> fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=16665e82580000)
> mounted in repro #4: https://storage.googleapis.com/syzbot-assets/6901c045125d/mount_15.gz
> fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=137355d4580000)
>
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+32415e0466b02533303c@syzkaller.appspotmail.com
>
> INFO: task syz.4.25:6211 blocked for more than 143 seconds.
> Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0
> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> task:syz.4.25 state:D stack:24616 pid:6211 tgid:6211 ppid:5990 task_flags:0x400040 flags:0x00004004
> Call Trace:
> <TASK>
> context_switch kernel/sched/core.c:5396 [inline]
> __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
> __schedule_loop kernel/sched/core.c:6863 [inline]
> schedule+0x165/0x360 kernel/sched/core.c:6878
> __bch2_two_state_lock+0x1ea/0x370 fs/bcachefs/two_state_shared_lock.c:7
> bch2_two_state_lock fs/bcachefs/two_state_shared_lock.h:55 [inline]
> bch2_page_fault+0x2f6/0x7a0 fs/bcachefs/fs-io-pagecache.c:592
> __do_fault+0x138/0x390 mm/memory.c:5189
> do_shared_fault mm/memory.c:5674 [inline]
> do_fault mm/memory.c:5748 [inline]
> do_pte_missing mm/memory.c:4251 [inline]
> handle_pte_fault mm/memory.c:6089 [inline]
> __handle_mm_fault+0x198b/0x5620 mm/memory.c:6232
> handle_mm_fault+0x2d5/0x7f0 mm/memory.c:6401
> do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
> handle_page_fault arch/x86/mm/fault.c:1476 [inline]
> exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
> asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
> RIP: 0033:0x7efe53d567c7
> RSP: 002b:00007ffd198848c8 EFLAGS: 00010203
> RAX: 0000200000002500 RBX: 0000000000000004 RCX: 0000200000002500
> RDX: 00002000000036e8 RSI: 00007efe53825cad RDI: 0000200000002520
> RBP: 00007efe53fb7ba0 R08: 0000000000000000 R09: 0000000000000049
> R10: 0000000000000000 R11: 0000000000000001 R12: 00007efe53fb616c
> R13: 00007efe53fb6160 R14: fffffffffffffffe R15: 00007ffd198849e0
> </TASK>
> INFO: task syz.4.25:6212 blocked for more than 144 seconds.
> Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0
> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> task:syz.4.25 state:D stack:17736 pid:6212 tgid:6211 ppid:5990 task_flags:0x440140 flags:0x00004006
> Call Trace:
> <TASK>
> context_switch kernel/sched/core.c:5396 [inline]
> __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
> __schedule_loop kernel/sched/core.c:6863 [inline]
> schedule+0x165/0x360 kernel/sched/core.c:6878
> __bch2_two_state_lock+0x1ea/0x370 fs/bcachefs/two_state_shared_lock.c:7
> bch2_two_state_lock fs/bcachefs/two_state_shared_lock.h:55 [inline]
> bch2_readahead+0x94f/0x1100 fs/bcachefs/fs-io-buffered.c:296
> read_pages+0x17a/0x580 mm/readahead.c:160
> page_cache_ra_order+0xa24/0xc70 mm/readahead.c:515
> filemap_readahead mm/filemap.c:2571 [inline]
> filemap_get_pages+0xb22/0x1ea0 mm/filemap.c:2616
> filemap_splice_read+0x4fc/0xbc0 mm/filemap.c:2990
> do_splice_read fs/splice.c:979 [inline]
> splice_direct_to_actor+0x4a6/0xcc0 fs/splice.c:1083
> do_splice_direct_actor fs/splice.c:1201 [inline]
> do_splice_direct+0x181/0x270 fs/splice.c:1227
> vfs_copy_file_range+0xabc/0x1310 fs/read_write.c:1627
> __do_sys_copy_file_range fs/read_write.c:1677 [inline]
> __se_sys_copy_file_range+0x2fb/0x470 fs/read_write.c:1644
> do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
> do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7efe53d8e929
> RSP: 002b:00007efe54b68038 EFLAGS: 00000246 ORIG_RAX: 0000000000000146
> RAX: ffffffffffffffda RBX: 00007efe53fb5fa0 RCX: 00007efe53d8e929
> RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000000000007
> RBP: 00007efe53e10b39 R08: 0000000000400000 R09: 0000000000000000
> R10: 00002000000000c0 R11: 0000000000000246 R12: 0000000000000000
> R13: 0000000000000000 R14: 00007efe53fb5fa0 R15: 00007ffd19884768
> </TASK>
> INFO: task syz.4.25:6264 blocked for more than 145 seconds.
> Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0
> "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> task:syz.4.25 state:D stack:25976 pid:6264 tgid:6211 ppid:5990 task_flags:0x400040 flags:0x00004006
> Call Trace:
> <TASK>
> context_switch kernel/sched/core.c:5396 [inline]
> __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
> __schedule_loop kernel/sched/core.c:6863 [inline]
> schedule+0x165/0x360 kernel/sched/core.c:6878
> io_schedule+0x81/0xe0 kernel/sched/core.c:7723
> folio_wait_bit_common+0x6b0/0xb90 mm/filemap.c:1317
> folio_lock include/linux/pagemap.h:1114 [inline]
> invalidate_inode_pages2_range+0x557/0xa80 mm/truncate.c:690
> bch2_write_invalidate_inode_pages_range+0xc5/0x110 fs/bcachefs/fs-io-pagecache.c:68
> bch2_direct_write+0x2a62/0x2ce0 fs/bcachefs/fs-io-direct.c:662
> bch2_write_iter+0x18f/0x2b90 fs/bcachefs/fs-io-buffered.c:1064
> do_iter_readv_writev+0x56b/0x7f0 fs/read_write.c:-1
> vfs_writev+0x31a/0x960 fs/read_write.c:1057
> do_pwritev fs/read_write.c:1153 [inline]
> __do_sys_pwritev2 fs/read_write.c:1211 [inline]
> __se_sys_pwritev2+0x179/0x290 fs/read_write.c:1202
> do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
> do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
> entry_SYSCALL_64_after_hwframe+0x77/0x7f
> RIP: 0033:0x7efe53d8e929
> RSP: 002b:00007efe54b47038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
> RAX: ffffffffffffffda RBX: 00007efe53fb6080 RCX: 00007efe53d8e929
> RDX: 0000000000000001 RSI: 0000200000000240 RDI: 0000000000000005
> RBP: 00007efe53e10b39 R08: 0000000000000000 R09: 0000000000000003
> R10: 0000000000007000 R11: 0000000000000246 R12: 0000000000000000
> R13: 0000000000000001 R14: 00007efe53fb6080 R15: 00007ffd19884768
> </TASK>
>
> Showing all locks held in the system:
> 1 lock held by khungtaskd/31:
> #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
> #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
> #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
> 3 locks held by kworker/0:2/1214:
> 2 locks held by getty/5584:
> #0: ffff88803543a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
> #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
> 3 locks held by syz-executor/5975:
> #0: ffff88805c16a0e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
> #0: ffff88805c16a0e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
> #0: ffff88805c16a0e0 (&type->s_umount_key#54){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
> #1: ffff8880ae700278 (&c->state_lock){+.+.}-{4:4}, at: __bch2_fs_stop+0xf8/0x900 fs/bcachefs/super.c:677
> #2: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
> #2: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
> 3 locks held by kworker/0:4/5981:
> 1 lock held by syz.4.25/6211:
> #0: ffff88805a860a88 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x2d9/0x1390 arch/x86/mm/fault.c:1327
> 1 lock held by syz.4.25/6212:
> #0: ffff8880564d1218 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
> #0: ffff8880564d1218 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: page_cache_ra_order+0x445/0xc70 mm/readahead.c:491
> 1 lock held by syz.4.25/6264:
> #0: ffff88802457a428 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
> #0: ffff88802457a428 (sb_writers#13){.+.+}-{0:0}, at: vfs_writev+0x288/0x960 fs/read_write.c:1055
> 1 lock held by syz.3.63/6745:
> #0: ffff888047965948 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x2d9/0x1390 arch/x86/mm/fault.c:1327
> 1 lock held by syz.3.63/6746:
> #0: ffff888056663810 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
> #0: ffff888056663810 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: page_cache_ra_order+0x445/0xc70 mm/readahead.c:491
> 1 lock held by syz.3.63/6801:
> #0: ffff88802a336428 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
> #0: ffff88802a336428 (sb_writers#13){.+.+}-{0:0}, at: vfs_writev+0x288/0x960 fs/read_write.c:1055
> 3 locks held by syz-executor/6934:
> #0: ffff88807577a0e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
> #0: ffff88807577a0e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
> #0: ffff88807577a0e0 (&type->s_umount_key#54){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
> #1: ffff8880b3780278 (&c->state_lock){+.+.}-{4:4}, at: __bch2_fs_stop+0xf8/0x900 fs/bcachefs/super.c:677
> #2: ffff8880b3780918 (&c->sb_lock){+.+.}-{4:4}, at: bch2_fs_mark_clean+0x44/0x380 fs/bcachefs/sb-clean.c:292
> 1 lock held by syz.5.115/7450:
> #0: ffff888054ecf808 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x2d9/0x1390 arch/x86/mm/fault.c:1327
> 1 lock held by syz.5.115/7451:
> #0: ffff8880564e5e08 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
> #0: ffff8880564e5e08 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: page_cache_ra_order+0x445/0xc70 mm/readahead.c:491
> 1 lock held by syz.5.115/7498:
> #0: ffff888030e24428 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
> #0: ffff888030e24428 (sb_writers#13){.+.+}-{0:0}, at: vfs_writev+0x288/0x960 fs/read_write.c:1055
> 1 lock held by syz.7.130/7767:
> #0: ffff888048694bc8 (vm_lock){++++}-{0:0}, at: do_user_addr_fault+0x2d9/0x1390 arch/x86/mm/fault.c:1327
> 1 lock held by syz.7.130/7768:
> #0: ffff8880564e3fa8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:934 [inline]
> #0: ffff8880564e3fa8 (mapping.invalidate_lock#3){.+.+}-{4:4}, at: page_cache_ra_order+0x445/0xc70 mm/readahead.c:491
> 1 lock held by syz.7.130/7816:
> #0: ffff888032802428 (sb_writers#13){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3096 [inline]
> #0: ffff888032802428 (sb_writers#13){.+.+}-{0:0}, at: vfs_writev+0x288/0x960 fs/read_write.c:1055
> 3 locks held by syz-executor/7973:
> #0: ffff88807b4300e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
> #0: ffff88807b4300e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
> #0: ffff88807b4300e0 (&type->s_umount_key#54){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
> #1: ffff888097700278 (&c->state_lock){+.+.}-{4:4}, at: __bch2_fs_stop+0xf8/0x900 fs/bcachefs/super.c:677
> #2: ffff888097700918 (&c->sb_lock){+.+.}-{4:4}, at: bch2_fs_mark_clean+0x44/0x380 fs/bcachefs/sb-clean.c:292
> 2 locks held by syz.2.173/8269:
>
> =============================================
>
> NMI backtrace for cpu 0
> CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0 PREEMPT(full)
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
> Call Trace:
> <TASK>
> dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
> nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
> nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
> trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
> check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
> watchdog+0xfee/0x1030 kernel/hung_task.c:470
> kthread+0x70e/0x8a0 kernel/kthread.c:464
> ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
> </TASK>
> Sending NMI from CPU 0 to CPUs 1:
> NMI backtrace for cpu 1
> CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0 PREEMPT(full)
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
> RIP: 0010:__orc_find arch/x86/kernel/unwind_orc.c:100 [inline]
> RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:227 [inline]
> RIP: 0010:unwind_next_frame+0x12e3/0x2390 arch/x86/kernel/unwind_orc.c:494
> Code: 18 48 8b 10 48 c7 c7 00 3a 88 8b 89 de e8 55 de b4 ff e9 43 06 00 00 49 89 d5 48 89 d5 48 89 d8 48 29 e8 48 89 c1 48 c1 f9 02 <48> c1 e8 3f 48 01 c8 48 83 e0 fe 4c 8d 3c 45 00 00 00 00 49 01 ef
> RSP: 0018:ffffc900001d7398 EFLAGS: 00000202
> RAX: 0000000000000004 RBX: ffffffff8fb37924 RCX: 0000000000000001
> RDX: ffffffff8fb37904 RSI: ffffffff902e9bf0 RDI: ffffffff8be1b7a0
> RBP: ffffffff8fb37920 R08: 0000000000000009 R09: ffffffff81729af5
> R10: ffffc900001d74c8 R11: fffff5200003aea5 R12: ffffffff8172c397
> R13: ffffffff8fb3791c R14: ffffc900001d74c8 R15: ffffffff8fb3791c
> FS: 0000000000000000(0000) GS:ffff888125d85000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007fc7ecf3d000 CR3: 000000002fea8000 CR4: 00000000003526f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
> <TASK>
> __unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
> unwind_start arch/x86/include/asm/unwind.h:64 [inline]
> arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
> stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
> kasan_save_stack mm/kasan/common.c:47 [inline]
> kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
> kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
> poison_slab_object mm/kasan/common.c:247 [inline]
> __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
> kasan_slab_free include/linux/kasan.h:233 [inline]
> slab_free_hook mm/slub.c:2381 [inline]
> slab_free mm/slub.c:4643 [inline]
> kfree+0x18e/0x440 mm/slub.c:4842
> slab_free_after_rcu_debug+0x60/0x2a0 mm/slub.c:4680
> rcu_do_batch kernel/rcu/tree.c:2576 [inline]
> rcu_core+0xca8/0x1710 kernel/rcu/tree.c:2832
> handle_softirqs+0x286/0x870 kernel/softirq.c:579
> run_ksoftirqd+0x9b/0x100 kernel/softirq.c:968
> smpboot_thread_fn+0x53f/0xa60 kernel/smpboot.c:164
> kthread+0x70e/0x8a0 kernel/kthread.c:464
> ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
> ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
> </TASK>
>
>
> ---
> If you want syzbot to run the reproducer, reply with:
> #syz test: git://repo/address.git branch-or-commit-hash
> If you attach or paste a git patch, syzbot will apply it before testing.
>
#syz fix: bcachefs: Fix readahead involved deadlock
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2025-08-08 5:40 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-12-13 22:41 [syzbot] [bcachefs?] INFO: task hung in bch2_page_fault syzbot
2025-06-17 16:52 ` syzbot
2025-08-08 5:40 ` Alan Huang
2025-06-21 1:50 ` syzbot
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