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BUG: sleeping function called from invalid context in synchronize_net

syzbot syzbot 3 participants 6 messages Jul 11, 2024 – Jul 20, 2024

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author syzbot
#0 lore raw

Hello,

syzbot found the following issue on:

HEAD commit:    523b23f0bee3 Add linux-next specific files for 20240710
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=10d88fb9980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=98dd8c4bab5cdce
dashboard link: https://syzkaller.appspot.com/bug?extid=9b277e2c2076e2661f61
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/345bcd25ed2f/disk-523b23f0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a4508962d345/vmlinux-523b23f0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4ba5eb555639/bzImage-523b23f0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:

Reported-by [email protected]
BUG: sleeping function called from invalid context at net/core/dev.c:11239

in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 12, name: kworker/u8:1
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
INFO: lockdep is turned off.

CPU: 1 UID: 0 PID: 12 Comm: kworker/u8:1 Not tainted 6.10.0-rc7-next-20240710-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: bond0 bond_mii_monitor
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 __might_resched+0x5d4/0x780 kernel/sched/core.c:8526
 synchronize_net+0x1b/0x50 net/core/dev.c:11239
 dev_deactivate_many+0x4a7/0xb10 net/sched/sch_generic.c:1371
 dev_deactivate+0x184/0x280 net/sched/sch_generic.c:1397
 linkwatch_do_dev+0x10a/0x170 net/core/link_watch.c:175
 ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:62
 bond_check_dev_link+0x1f1/0x3f0 drivers/net/bonding/bond_main.c:757
 bond_miimon_inspect drivers/net/bonding/bond_main.c:2604 [inline]
 bond_mii_monitor+0x49a/0x3170 drivers/net/bonding/bond_main.c:2826
 process_one_work kernel/workqueue.c:3228 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3309
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3387
 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>
------------[ cut here ]------------
Voluntary context switch within RCU read-side critical section!
WARNING: CPU: 1 PID: 12 at kernel/rcu/tree_plugin.h:330 rcu_note_context_switch+0xcf4/0xff0 kernel/rcu/tree_plugin.h:330
Modules linked in:
CPU: 1 UID: 0 PID: 12 Comm: kworker/u8:1 Tainted: G        W          6.10.0-rc7-next-20240710-syzkaller #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: bond0 bond_mii_monitor
RIP: 0010:rcu_note_context_switch+0xcf4/0xff0 kernel/rcu/tree_plugin.h:330
Code: 00 ba 02 00 00 00 e8 bb 02 fe ff 4c 8b b4 24 80 00 00 00 eb 91 c6 05 a4 4f 1f 0e 01 90 48 c7 c7 e0 2d cc 8b e8 ad c5 da ff 90 <0f> 0b 90 90 e9 3b f4 ff ff 90 0f 0b 90 45 84 ed 0f 84 00 f4 ff ff
RSP: 0018:ffffc90000116f00 EFLAGS: 00010046
RAX: b02efd3a29e78a00 RBX: ffff8880172cde44 RCX: ffff8880172cda00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000117050 R08: ffffffff815583f2 R09: fffffbfff1c39f8c
R10: dffffc0000000000 R11: fffffbfff1c39f8c R12: ffff8880172cda00
R13: 0000000000000000 R14: 1ffff92000022df8 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c444d58 CR3: 000000006ca0e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __schedule+0x348/0x4a60 kernel/sched/core.c:6491
 __schedule_loop kernel/sched/core.c:6680 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6695
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6752
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752
 exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
 synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:967
 synchronize_rcu+0x11b/0x360 kernel/rcu/tree.c:4020
 dev_deactivate_many+0x4a7/0xb10 net/sched/sch_generic.c:1371
 dev_deactivate+0x184/0x280 net/sched/sch_generic.c:1397
 linkwatch_do_dev+0x10a/0x170 net/core/link_watch.c:175
 ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:62
 bond_check_dev_link+0x1f1/0x3f0 drivers/net/bonding/bond_main.c:757
 bond_miimon_inspect drivers/net/bonding/bond_main.c:2604 [inline]
 bond_mii_monitor+0x49a/0x3170 drivers/net/bonding/bond_main.c:2826
 process_one_work kernel/workqueue.c:3228 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3309
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3387
 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>

---
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 [email protected].

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author syzbot
#1 lore raw
syzbot has found a reproducer for the following issue on:

syzbot has found a reproducer for the following issue on:

HEAD commit:    523b23f0bee3 Add linux-next specific files for 20240710
git tree:       linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=11b62585980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=98dd8c4bab5cdce
dashboard link: https://syzkaller.appspot.com/bug?extid=9b277e2c2076e2661f61
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=148611e1980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10ec9585980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/345bcd25ed2f/disk-523b23f0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a4508962d345/vmlinux-523b23f0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4ba5eb555639/bzImage-523b23f0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:

Reported-by [email protected]
BUG: sleeping function called from invalid context at net/core/dev.c:11239

in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 1046, name: kworker/u8:5
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
INFO: lockdep is turned off.

CPU: 0 UID: 0 PID: 1046 Comm: kworker/u8:5 Not tainted 6.10.0-rc7-next-20240710-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: bond0 bond_mii_monitor
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 __might_resched+0x5d4/0x780 kernel/sched/core.c:8526
 synchronize_net+0x1b/0x50 net/core/dev.c:11239
 dev_deactivate_many+0x4a7/0xb10 net/sched/sch_generic.c:1371
 dev_deactivate+0x184/0x280 net/sched/sch_generic.c:1397
 linkwatch_do_dev+0x10a/0x170 net/core/link_watch.c:175
 ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:62
 bond_check_dev_link+0x1f1/0x3f0 drivers/net/bonding/bond_main.c:757
 bond_miimon_inspect drivers/net/bonding/bond_main.c:2604 [inline]
 bond_mii_monitor+0x49a/0x3170 drivers/net/bonding/bond_main.c:2826
 process_one_work kernel/workqueue.c:3228 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3309
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3387
 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>
------------[ cut here ]------------
Voluntary context switch within RCU read-side critical section!
WARNING: CPU: 1 PID: 1046 at kernel/rcu/tree_plugin.h:330 rcu_note_context_switch+0xcf4/0xff0 kernel/rcu/tree_plugin.h:330
Modules linked in:
CPU: 1 UID: 0 PID: 1046 Comm: kworker/u8:5 Tainted: G        W          6.10.0-rc7-next-20240710-syzkaller #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: bond0 bond_mii_monitor
RIP: 0010:rcu_note_context_switch+0xcf4/0xff0 kernel/rcu/tree_plugin.h:330
Code: 00 ba 02 00 00 00 e8 bb 02 fe ff 4c 8b b4 24 80 00 00 00 eb 91 c6 05 a4 4f 1f 0e 01 90 48 c7 c7 e0 2d cc 8b e8 ad c5 da ff 90 <0f> 0b 90 90 e9 3b f4 ff ff 90 0f 0b 90 45 84 ed 0f 84 00 f4 ff ff
RSP: 0018:ffffc900041cefc0 EFLAGS: 00010046
RAX: 583d87a6c7750500 RBX: ffff88802123de44 RCX: ffff88802123da00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900041cf110 R08: ffffffff815583f2 R09: fffffbfff1c39f8c
R10: dffffc0000000000 R11: fffffbfff1c39f8c R12: ffff88802123da00
R13: 0000000000000000 R14: 1ffff92000839e10 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5b6614bbe3 CR3: 0000000022676000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __schedule+0x348/0x4a60 kernel/sched/core.c:6491
 __schedule_loop kernel/sched/core.c:6680 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6695
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6752
 __mutex_lock_common kernel/locking/mutex.c:684 [inline]
 __mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752
 exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
 synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:967
 dev_deactivate_many+0x4a7/0xb10 net/sched/sch_generic.c:1371
 dev_deactivate+0x184/0x280 net/sched/sch_generic.c:1397
 linkwatch_do_dev+0x10a/0x170 net/core/link_watch.c:175
 ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:62
 bond_check_dev_link+0x1f1/0x3f0 drivers/net/bonding/bond_main.c:757
 bond_miimon_inspect drivers/net/bonding/bond_main.c:2604 [inline]
 bond_mii_monitor+0x49a/0x3170 drivers/net/bonding/bond_main.c:2826
 process_one_work kernel/workqueue.c:3228 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3309
 worker_thread+0x86d/0xd40 kernel/workqueue.c:3387
 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>

---
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.

#2 lore raw

On Thu, 11 Jul 2024 14:10:22 -0700

Quoted 5 lines

syzbot has found a reproducer for the following issue on:

HEAD commit:    523b23f0bee3 Add linux-next specific files for 20240710
git tree:       linux-next
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10ec9585980000

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 523b23f0bee3

net/ethtool/ioctl.c +4 -3
@@ -58,10 +58,11 @@ static struct devlink *netdev_to_devlink
 
 u32 ethtool_op_get_link(struct net_device *dev)
 {
-	/* Synchronize carrier state with link watch, see also rtnl_getlink() */
-	linkwatch_sync_dev(dev);
+	u32 rc = netif_carrier_ok(dev) ? 1 : 0;
 
-	return netif_carrier_ok(dev) ? 1 : 0;
+	linkwatch_fire_event(NULL);
+
+	return rc;
 }
 EXPORT_SYMBOL(ethtool_op_get_link);
net/core/link_watch.c +5 -1
@@ -286,13 +286,17 @@ static void linkwatch_event(struct work_
 
 void linkwatch_fire_event(struct net_device *dev)
 {
-	bool urgent = linkwatch_urgent_event(dev);
+	bool urgent = true;
 
+	if (!dev)
+		goto sched;
+	urgent = linkwatch_urgent_event(dev);
 	if (!test_and_set_bit(__LINK_STATE_LINKWATCH_PENDING, &dev->state)) {
 		linkwatch_add_event(dev);
 	} else if (!urgent)
 		return;
 
+sched:
 	linkwatch_schedule_work(urgent);
 }
 EXPORT_SYMBOL(linkwatch_fire_event);

--

author syzbot
#3 lore raw
syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by [email protected]

Tested on:

commit:         523b23f0 Add linux-next specific files for 20240710
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
console output: https://syzkaller.appspot.com/x/log.txt?x=10241c2d980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=98dd8c4bab5cdce
dashboard link: https://syzkaller.appspot.com/bug?extid=9b277e2c2076e2661f61
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
patch:          https://syzkaller.appspot.com/x/patch.diff?x=15cdcd9e980000

Note: testing is done by a robot and is best-effort only.

#4 lore raw
In reply to syzbot
Quoted 4 lines · syzbot

Hello,

syzbot found the following issue on:

Quoted 8 lines
HEAD commit:    523b23f0bee3 Add linux-next specific files for 20240710
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=10d88fb9980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=98dd8c4bab5cdce
dashboard link: https://syzkaller.appspot.com/bug?extid=9b277e2c2076e2661f61
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.

Looking at the code, I'm pretty sure this can happen when:

a) the bond is configured with use_carrier = 0; this causes
bonding to query ethtool to get carrier state.

	b) bond_mii_monitor runs while dev->link_watch_list is

non-empty, in this case with a pending link down transition. In this case, linkwatch_sync_dev (called by ethtool_op_get_link) will in turn call linkwatch_do_dev -> dev_deactivate -> dev_deactivate_many -> synchronize_net -> might_sleep.

The use_carrier option was added 20-ish years ago for device
drivers that didn't do netif_carrier_on / _off at the time.

I was about to say that I'd expect all drivers today to do
netif_carrier, but 1386c36b3038 ("bonding: allow carrier and link status to determine link state") suggests that something needed it as recently as 2018.

	-J
Quoted 99 lines

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/345bcd25ed2f/disk-523b23f0.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/a4508962d345/vmlinux-523b23f0.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4ba5eb555639/bzImage-523b23f0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:

Reported-by [email protected]
BUG: sleeping function called from invalid context at net/core/dev.c:11239

in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 12, name: kworker/u8:1
preempt_count: 0, expected: 0
RCU nest depth: 1, expected: 0
INFO: lockdep is turned off.

CPU: 1 UID: 0 PID: 12 Comm: kworker/u8:1 Not tainted 6.10.0-rc7-next-20240710-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: bond0 bond_mii_monitor
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
__might_resched+0x5d4/0x780 kernel/sched/core.c:8526
synchronize_net+0x1b/0x50 net/core/dev.c:11239
dev_deactivate_many+0x4a7/0xb10 net/sched/sch_generic.c:1371
dev_deactivate+0x184/0x280 net/sched/sch_generic.c:1397
linkwatch_do_dev+0x10a/0x170 net/core/link_watch.c:175
ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:62
bond_check_dev_link+0x1f1/0x3f0 drivers/net/bonding/bond_main.c:757
bond_miimon_inspect drivers/net/bonding/bond_main.c:2604 [inline]
bond_mii_monitor+0x49a/0x3170 drivers/net/bonding/bond_main.c:2826
process_one_work kernel/workqueue.c:3228 [inline]
process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3309
worker_thread+0x86d/0xd40 kernel/workqueue.c:3387
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>
------------[ cut here ]------------
Voluntary context switch within RCU read-side critical section!
WARNING: CPU: 1 PID: 12 at kernel/rcu/tree_plugin.h:330 rcu_note_context_switch+0xcf4/0xff0 kernel/rcu/tree_plugin.h:330
Modules linked in:
CPU: 1 UID: 0 PID: 12 Comm: kworker/u8:1 Tainted: G        W          6.10.0-rc7-next-20240710-syzkaller #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: bond0 bond_mii_monitor
RIP: 0010:rcu_note_context_switch+0xcf4/0xff0 kernel/rcu/tree_plugin.h:330
Code: 00 ba 02 00 00 00 e8 bb 02 fe ff 4c 8b b4 24 80 00 00 00 eb 91 c6 05 a4 4f 1f 0e 01 90 48 c7 c7 e0 2d cc 8b e8 ad c5 da ff 90 <0f> 0b 90 90 e9 3b f4 ff ff 90 0f 0b 90 45 84 ed 0f 84 00 f4 ff ff
RSP: 0018:ffffc90000116f00 EFLAGS: 00010046
RAX: b02efd3a29e78a00 RBX: ffff8880172cde44 RCX: ffff8880172cda00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000117050 R08: ffffffff815583f2 R09: fffffbfff1c39f8c
R10: dffffc0000000000 R11: fffffbfff1c39f8c R12: ffff8880172cda00
R13: 0000000000000000 R14: 1ffff92000022df8 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c444d58 CR3: 000000006ca0e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__schedule+0x348/0x4a60 kernel/sched/core.c:6491
__schedule_loop kernel/sched/core.c:6680 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6695
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6752
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x6a4/0xd70 kernel/locking/mutex.c:752
exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:967
synchronize_rcu+0x11b/0x360 kernel/rcu/tree.c:4020
dev_deactivate_many+0x4a7/0xb10 net/sched/sch_generic.c:1371
dev_deactivate+0x184/0x280 net/sched/sch_generic.c:1397
linkwatch_do_dev+0x10a/0x170 net/core/link_watch.c:175
ethtool_op_get_link+0x15/0x60 net/ethtool/ioctl.c:62
bond_check_dev_link+0x1f1/0x3f0 drivers/net/bonding/bond_main.c:757
bond_miimon_inspect drivers/net/bonding/bond_main.c:2604 [inline]
bond_mii_monitor+0x49a/0x3170 drivers/net/bonding/bond_main.c:2826
process_one_work kernel/workqueue.c:3228 [inline]
process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3309
worker_thread+0x86d/0xd40 kernel/workqueue.c:3387
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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---
-Jay Vosburgh, [email protected]

author syzbot
#5 lore raw
In reply to syzbot
syzbot has bisected this issue to:

syzbot has bisected this issue to:

commit facd15dfd69122042502d99ab8c9f888b48ee994

Author: Johannes Berg <[email protected]>
Date:   Mon Dec 4 20:47:07 2023 +0000

net: core: synchronize link-watch when carrier is queried

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=116d4a1d980000
start commit:   523b23f0bee3 Add linux-next specific files for 20240710
git tree:       linux-next
final oops:     https://syzkaller.appspot.com/x/report.txt?x=136d4a1d980000
console output: https://syzkaller.appspot.com/x/log.txt?x=156d4a1d980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=98dd8c4bab5cdce
dashboard link: https://syzkaller.appspot.com/bug?extid=9b277e2c2076e2661f61
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=148611e1980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10ec9585980000
Reported-by [email protected]
Fixes facd15dfd691 ("net: core: synchronize link-watch when carrier is queried")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection