* [syzbot] [kernel?] WARNING in enqueue_dl_entity
@ 2024-09-28 17:15 syzbot
2024-11-22 22:48 ` syzbot
0 siblings, 1 reply; 6+ messages in thread
From: syzbot @ 2024-09-28 17:15 UTC (permalink / raw)
To: akpm, linux-kernel, linux-mm, syzkaller-bugs
Hello,
syzbot found the following issue on:
HEAD commit: 13882369ceb9 Merge tag 'hid-for-linus-2024092601' of git:/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17334507980000
kernel config: https://syzkaller.appspot.com/x/.config?x=f1af1dc2e43cf22f
dashboard link: https://syzkaller.appspot.com/bug?extid=00a022dc9979d67df050
compiler: aarch64-linux-gnu-gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/384ffdcca292/non_bootable_disk-13882369.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a1a2db588faf/vmlinux-13882369.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a3f594a63d31/Image-13882369.gz.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+00a022dc9979d67df050@syzkaller.appspotmail.com
------------[ cut here ]------------
WARNING: CPU: 1 PID: 34 at kernel/sched/deadline.c:1995 enqueue_dl_entity+0x47c/0x590 kernel/sched/deadline.c:2029
Modules linked in:
CPU: 1 UID: 0 PID: 34 Comm: kcompactd0 Tainted: G B 6.11.0-syzkaller-10729-g13882369ceb9 #0
Tainted: [B]=BAD_PAGE
Hardware name: linux,dummy-virt (DT)
pstate: a14000c9 (NzCv daIF +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : enqueue_dl_entity+0x47c/0x590 kernel/sched/deadline.c:1995
lr : dl_server_start+0x44/0x12c kernel/sched/deadline.c:1650
sp : ffff800082eab970
x29: ffff800082eab970 x28: f3f0000004f45c00 x27: 0000000000000000
x26: 0000000000000001 x25: 0000000000000000 x24: 0000000000000048
x23: fff000007f8ee800 x22: 0000000000000001 x21: 000000000016e360
x20: 0000000000000001 x19: fff000007f8ef168 x18: 0000000000000000
x17: fff07ffffd1e0000 x16: ffff800080008000 x15: 0000000000000000
x14: 00000000000002e1 x13: 0000000000000377 x12: 0000000000000001
x11: fff000007f8ee880 x10: 0000000000000001 x9 : 0000000000000048
x8 : 0000000000100000 x7 : 0000000000000001 x6 : f3f0000004f45bc0
x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 0000000000000001 x1 : 0000000000000001 x0 : 0000000000000001
Call trace:
enqueue_dl_entity+0x47c/0x590 kernel/sched/deadline.c:2029
dl_server_start+0x44/0x12c kernel/sched/deadline.c:1650
enqueue_task_fair+0x11c/0x3a4 kernel/sched/fair.c:7040
enqueue_task+0x58/0xbc kernel/sched/core.c:2020
activate_task+0x68/0x80 kernel/sched/core.c:2062
attach_task+0x4c/0x74 kernel/sched/fair.c:9631
attach_tasks kernel/sched/fair.c:9666 [inline]
sched_balance_rq+0x488/0xc74 kernel/sched/fair.c:11743
sched_balance_newidle.constprop.0+0x1b0/0x3e4 kernel/sched/fair.c:12785
pick_next_task_fair+0x50/0x320 kernel/sched/fair.c:8933
__pick_next_task kernel/sched/core.c:5955 [inline]
pick_next_task kernel/sched/core.c:6477 [inline]
__schedule+0x158/0x8e8 kernel/sched/core.c:6629
__schedule_loop kernel/sched/core.c:6752 [inline]
schedule+0x34/0x104 kernel/sched/core.c:6767
schedule_timeout+0x80/0xf4 kernel/time/timer.c:2615
kcompactd+0x204/0x374 mm/compaction.c:3181
kthread+0x114/0x118 kernel/kthread.c:389
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860
---[ end trace 0000000000000000 ]---
---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.
syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title
If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)
If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report
If you want to undo deduplication, reply with:
#syz undup
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [syzbot] [kernel?] WARNING in enqueue_dl_entity
2024-09-28 17:15 [syzbot] [kernel?] WARNING in enqueue_dl_entity syzbot
@ 2024-11-22 22:48 ` syzbot
2024-11-23 2:10 ` Hillf Danton
2024-12-13 11:03 ` Hillf Danton
0 siblings, 2 replies; 6+ messages in thread
From: syzbot @ 2024-11-22 22:48 UTC (permalink / raw)
To: akpm, bsegall, dietmar.eggemann, juri.lelli, linux-kernel,
linux-mm, mgorman, mingo, peterz, rostedt, syzkaller-bugs,
vincent.guittot, vschneid
syzbot has found a reproducer for the following issue on:
HEAD commit: 28eb75e178d3 Merge tag 'drm-next-2024-11-21' of https://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1402175f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=5606b6814de0f638
dashboard link: https://syzkaller.appspot.com/bug?extid=00a022dc9979d67df050
compiler: aarch64-linux-gnu-gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1016fec0580000
Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/384ffdcca292/non_bootable_disk-28eb75e1.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4053ed867efd/vmlinux-28eb75e1.xz
kernel image: https://storage.googleapis.com/syzbot-assets/903039310aac/Image-28eb75e1.gz.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+00a022dc9979d67df050@syzkaller.appspotmail.com
------------[ cut here ]------------
WARNING: CPU: 0 PID: 10 at kernel/sched/deadline.c:1995 enqueue_dl_entity+0x478/0x58c kernel/sched/deadline.c:2029
Modules linked in:
CPU: 0 UID: 0 PID: 10 Comm: kworker/0:1 Not tainted 6.12.0-syzkaller-07749-g28eb75e178d3 #0
Hardware name: linux,dummy-virt (DT)
Workqueue: 0x0 (events)
pstate: a14000c9 (NzCv daIF +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : enqueue_dl_entity+0x478/0x58c kernel/sched/deadline.c:1995
lr : dl_server_start+0x44/0x12c kernel/sched/deadline.c:1650
sp : ffff800082b33a10
x29: ffff800082b33a10 x28: fdf0000004e5dc00 x27: 0000000000000000
x26: 0000000000000001 x25: 0000000000000000 x24: 0000000000000048
x23: fff000007f8d7600 x22: 0000000000000001 x21: 000000000016e360
x20: 0000000000000001 x19: fff000007f8d7f68 x18: 0000000000000000
x17: 0000000000000004 x16: 0000000000000002 x15: 0000000000000000
x14: 0000000000000142 x13: 00000000000003db x12: 0000000000000001
x11: fff000007f8d7680 x10: 0000000000000284 x9 : 0000000000000048
x8 : 0000000000100000 x7 : 0000000000000000 x6 : fdf0000004e5dbc0
x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 0000000000000001 x1 : 0000000000000001 x0 : 0000000000000001
Call trace:
enqueue_dl_entity+0x478/0x58c kernel/sched/deadline.c:2029 (P)
dl_server_start+0x44/0x12c kernel/sched/deadline.c:1650 (L)
dl_server_start+0x44/0x12c kernel/sched/deadline.c:1650
enqueue_task_fair+0x11c/0x3a4 kernel/sched/fair.c:7038
enqueue_task+0x3c/0xe4 kernel/sched/core.c:2061
activate_task+0x68/0x80 kernel/sched/core.c:2108
attach_task+0x4c/0x74 kernel/sched/fair.c:9635
attach_tasks kernel/sched/fair.c:9670 [inline]
sched_balance_rq+0x580/0xc74 kernel/sched/fair.c:11747
sched_balance_newidle.constprop.0+0x1b0/0x3e4 kernel/sched/fair.c:12789
pick_next_task_fair+0x50/0x320 kernel/sched/fair.c:8937
__pick_next_task kernel/sched/core.c:6023 [inline]
pick_next_task kernel/sched/core.c:6542 [inline]
__schedule+0x15c/0x900 kernel/sched/core.c:6709
__schedule_loop kernel/sched/core.c:6833 [inline]
schedule+0x34/0x104 kernel/sched/core.c:6848
worker_thread+0x19c/0x354 kernel/workqueue.c:3406
kthread+0x114/0x118 kernel/kthread.c:389
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:862
---[ end trace 0000000000000000 ]---
---
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] 6+ messages in thread
* Re: [syzbot] [kernel?] WARNING in enqueue_dl_entity
2024-11-22 22:48 ` syzbot
@ 2024-11-23 2:10 ` Hillf Danton
2024-11-23 2:12 ` syzbot
2024-12-13 11:03 ` Hillf Danton
1 sibling, 1 reply; 6+ messages in thread
From: Hillf Danton @ 2024-11-23 2:10 UTC (permalink / raw)
To: syzbot; +Cc: linux-kernel, syzkaller-bugs
On Fri, 22 Nov 2024 14:48:23 -0800
> syzbot has found a reproducer for the following issue on:
>
> HEAD commit: 28eb75e178d3 Merge tag 'drm-next-2024-11-21' of https://gi..
> git tree: upstream
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1016fec0580000
#syz test upstream master
--- x/kernel/sched/fair.c
+++ y/kernel/sched/fair.c
@@ -7151,8 +7151,11 @@ static int dequeue_entities(struct rq *r
idle_h_nr_running = h_nr_running;
/* end evaluation on encountering a throttled cfs_rq */
- if (cfs_rq_throttled(cfs_rq))
+ if (cfs_rq_throttled(cfs_rq)) {
+ if (rq_h_nr_running && !rq->cfs.h_nr_running)
+ dl_server_stop(&rq->fair_server);
return 0;
+ }
}
sub_nr_running(rq, h_nr_running);
--
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [syzbot] [kernel?] WARNING in enqueue_dl_entity
2024-11-23 2:10 ` Hillf Danton
@ 2024-11-23 2:12 ` syzbot
0 siblings, 0 replies; 6+ messages in thread
From: syzbot @ 2024-11-23 2:12 UTC (permalink / raw)
To: hdanton, linux-kernel, syzkaller-bugs
Hello,
syzbot tried to test the proposed patch but the build/boot failed:
syzkaller build failed: failed to run ["make" "target"]: exit status 2
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
go list -f '{{.Stale}}' ./sys/syz-sysgen | grep -q false || go install ./sys/syz-sysgen
go: error obtaining buildID for go tool compile: fork/exec /syzkaller/jobs/linux/gopath/pkg/mod/golang.org/toolchain@v0.0.1-go1.22.1.linux-amd64/pkg/tool/linux_amd64/compile: resource temporarily unavailable
error obtaining VCS status: exit status 128
Use -buildvcs=false to disable VCS stamping.
make: *** [Makefile:147: descriptions] Error 1
go env (err=<nil>)
GO111MODULE='auto'
GOARCH='amd64'
GOBIN=''
GOCACHE='/syzkaller/.cache/go-build'
GOENV='/syzkaller/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMODCACHE='/syzkaller/jobs/linux/gopath/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/syzkaller/jobs/linux/gopath'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/syzkaller/jobs/linux/gopath/pkg/mod/golang.org/toolchain@v0.0.1-go1.22.1.linux-amd64'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/syzkaller/jobs/linux/gopath/pkg/mod/golang.org/toolchain@v0.0.1-go1.22.1.linux-amd64/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.22.1'
GCCGO='gccgo'
GOAMD64='v1'
AR='ar'
CC='gcc'
CXX='g++'
CGO_ENABLED='1'
GOMOD='/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/go.mod'
GOWORK=''
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build10930050=/tmp/go-build -gno-record-gcc-switches'
git status (err=<nil>)
HEAD detached at 4dfba2774
nothing to commit, working tree clean
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
go list -f '{{.Stale}}' ./sys/syz-sysgen | grep -q false || go install ./sys/syz-sysgen
go: error obtaining buildID for go tool compile: fork/exec /syzkaller/jobs/linux/gopath/pkg/mod/golang.org/toolchain@v0.0.1-go1.22.1.linux-amd64/pkg/tool/linux_amd64/compile: resource temporarily unavailable
error obtaining VCS status: exit status 128
Use -buildvcs=false to disable VCS stamping.
make: *** [Makefile:147: descriptions] Error 1
Tested on:
commit: [unknown
git tree: upstream
kernel config: https://syzkaller.appspot.com/x/.config?x=5606b6814de0f638
dashboard link: https://syzkaller.appspot.com/bug?extid=00a022dc9979d67df050
compiler:
userspace arch: arm64
patch: https://syzkaller.appspot.com/x/patch.diff?x=174836e8580000
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [syzbot] [kernel?] WARNING in enqueue_dl_entity
2024-11-22 22:48 ` syzbot
2024-11-23 2:10 ` Hillf Danton
@ 2024-12-13 11:03 ` Hillf Danton
2024-12-13 11:32 ` syzbot
1 sibling, 1 reply; 6+ messages in thread
From: Hillf Danton @ 2024-12-13 11:03 UTC (permalink / raw)
To: syzbot; +Cc: linux-kernel, syzkaller-bugs
On Fri, 22 Nov 2024 14:48:23 -0800
> syzbot has found a reproducer for the following issue on:
>
> HEAD commit: 28eb75e178d3 Merge tag 'drm-next-2024-11-21' of https://gi..
> git tree: upstream
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1016fec0580000
Test fix (https://lore.kernel.org/lkml/20241213032244.877029-1-vineeth@bitbyteword.org/ )
#syz test upstream master
diff -pur x/include/linux/sched.h y/include/linux/sched.h
--- x/include/linux/sched.h 2024-12-13 18:53:21.592682100 +0800
+++ y/include/linux/sched.h 2024-12-13 18:55:17.754180400 +0800
@@ -656,6 +656,12 @@ struct sched_dl_entity {
* @dl_defer_armed tells if the deferrable server is waiting
* for the replenishment timer to activate it.
*
+ * @dl_server_active tells if the dlserver is active(started).
+ * dlserver is started on first cfs enqueue on an idle runqueue
+ * and is stopped when a dequeue results in 0 cfs tasks on the
+ * runqueue. In other words, dlserver is active only when cpu's
+ * runqueue has atleast one cfs task.
+ *
* @dl_defer_running tells if the deferrable server is actually
* running, skipping the defer phase.
*/
@@ -664,6 +670,7 @@ struct sched_dl_entity {
unsigned int dl_non_contending : 1;
unsigned int dl_overrun : 1;
unsigned int dl_server : 1;
+ unsigned int dl_server_active : 1;
unsigned int dl_defer : 1;
unsigned int dl_defer_armed : 1;
unsigned int dl_defer_running : 1;
diff -pur x/kernel/sched/deadline.c y/kernel/sched/deadline.c
--- x/kernel/sched/deadline.c 2024-12-13 18:51:17.093081100 +0800
+++ y/kernel/sched/deadline.c 2024-12-13 18:55:17.770211500 +0800
@@ -1647,6 +1647,7 @@ void dl_server_start(struct sched_dl_ent
if (!dl_se->dl_runtime)
return;
+ dl_se->dl_server_active = 1;
enqueue_dl_entity(dl_se, ENQUEUE_WAKEUP);
if (!dl_task(dl_se->rq->curr) || dl_entity_preempt(dl_se, &rq->curr->dl))
resched_curr(dl_se->rq);
@@ -1661,6 +1662,7 @@ void dl_server_stop(struct sched_dl_enti
hrtimer_try_to_cancel(&dl_se->dl_timer);
dl_se->dl_defer_armed = 0;
dl_se->dl_throttled = 0;
+ dl_se->dl_server_active = 0;
}
void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
@@ -2421,8 +2423,10 @@ again:
if (dl_server(dl_se)) {
p = dl_se->server_pick_task(dl_se);
if (!p) {
- dl_se->dl_yielded = 1;
- update_curr_dl_se(rq, dl_se, 0);
+ if (dl_server_active(dl_se)) {
+ dl_se->dl_yielded = 1;
+ update_curr_dl_se(rq, dl_se, 0);
+ }
goto again;
}
rq->dl_server = dl_se;
diff -pur x/kernel/sched/fair.c y/kernel/sched/fair.c
--- x/kernel/sched/fair.c 2024-12-13 18:50:13.649803300 +0800
+++ y/kernel/sched/fair.c 2024-12-13 18:56:11.779225700 +0800
@@ -1159,8 +1159,6 @@ static inline void update_curr_task(stru
trace_sched_stat_runtime(p, delta_exec);
account_group_exec_runtime(p, delta_exec);
cgroup_account_cputime(p, delta_exec);
- if (p->dl_server)
- dl_server_update(p->dl_server, delta_exec);
}
static inline bool did_preempt_short(struct cfs_rq *cfs_rq, struct sched_entity *curr)
@@ -1237,11 +1235,16 @@ static void update_curr(struct cfs_rq *c
update_curr_task(p, delta_exec);
/*
- * Any fair task that runs outside of fair_server should
- * account against fair_server such that it can account for
- * this time and possibly avoid running this period.
+ * If the fair_server is active, we need to account for the
+ * fair_server time whether or not the task is running on
+ * behalf of fair_server or not:
+ * - If the task is running on behalf of fair_server, we need
+ * to limit its time based on the assigned runtime.
+ * - Fair task that runs outside of fair_server should account
+ * against fair_server such that it can account for this time
+ * and possibly avoid running this period.
*/
- if (p->dl_server != &rq->fair_server)
+ if (dl_server_active(&rq->fair_server))
dl_server_update(&rq->fair_server, delta_exec);
}
diff -pur x/kernel/sched/sched.h y/kernel/sched/sched.h
--- x/kernel/sched/sched.h 2024-12-13 18:50:42.985005300 +0800
+++ y/kernel/sched/sched.h 2024-12-13 18:55:17.801793100 +0800
@@ -398,6 +398,11 @@ extern void __dl_server_attach_root(stru
extern int dl_server_apply_params(struct sched_dl_entity *dl_se,
u64 runtime, u64 period, bool init);
+static inline bool dl_server_active(struct sched_dl_entity *dl_se)
+{
+ return dl_se->dl_server_active;
+}
+
#ifdef CONFIG_CGROUP_SCHED
extern struct list_head task_groups;
--
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [syzbot] [kernel?] WARNING in enqueue_dl_entity
2024-12-13 11:03 ` Hillf Danton
@ 2024-12-13 11:32 ` syzbot
0 siblings, 0 replies; 6+ messages in thread
From: syzbot @ 2024-12-13 11:32 UTC (permalink / raw)
To: hdanton, linux-kernel, syzkaller-bugs
Hello,
syzbot has tested the proposed patch and the reproducer did not trigger any issue:
Reported-by: syzbot+00a022dc9979d67df050@syzkaller.appspotmail.com
Tested-by: syzbot+00a022dc9979d67df050@syzkaller.appspotmail.com
Tested on:
commit: f932fb9b Merge tag 'v6.13-rc2-ksmbd-server-fixes' of g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14a12d44580000
kernel config: https://syzkaller.appspot.com/x/.config?x=a42226445f75136a
dashboard link: https://syzkaller.appspot.com/bug?extid=00a022dc9979d67df050
compiler: aarch64-linux-gnu-gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64
patch: https://syzkaller.appspot.com/x/patch.diff?x=1567c4f8580000
Note: testing is done by a robot and is best-effort only.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2024-12-13 11:32 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2024-09-28 17:15 [syzbot] [kernel?] WARNING in enqueue_dl_entity syzbot
2024-11-22 22:48 ` syzbot
2024-11-23 2:10 ` Hillf Danton
2024-11-23 2:12 ` syzbot
2024-12-13 11:03 ` Hillf Danton
2024-12-13 11:32 ` syzbot
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