Re: [syzbot] WARNING in kthread_is_per_cpu
On 20/04/21 12:11, Peter Zijlstra wrote: > On Tue, Apr 20, 2021 at 10:43:43AM +0100, Valentin Schneider wrote: >> On 20/04/21 10:51, Peter Zijlstra wrote: > >> > I think free_kthread_struct() is ok, because a task at that point in its >> > lifetime cannot be also doing exec(). >> > >> >> What if it's one of those kthreads created by directly invoking >> kernel_thread()? AFAICT right now it's only umh, and that one does execve() >> so it ends up stripped of PF_KTHREAD. It could however go through an error >> path, i.e. not call exec, and exit, giving us: >> >> put_task_struct(p) >> `\ >> free_task(p) >> `\ >> if (tsk->flags & PF_KTHREAD) >> free_kthread_struct(tsk); >> `\ >> to_kthread(p) > > I'm not following, at the point we hit free_task() it had better be dead > and p->flags had better be stable. Either it will, or will not, have > PF_KTHREAD. Bah, don't mind me, for some reason I was obsessed by that umh thing of having (p->flags & PF_KTHREAD) && !p->set_child_tid but that's not a problem there. Sorry about that.
Re: [syzbot] WARNING in kthread_is_per_cpu
On Tue, Apr 20, 2021 at 10:43:43AM +0100, Valentin Schneider wrote: > On 20/04/21 10:51, Peter Zijlstra wrote: > > I think free_kthread_struct() is ok, because a task at that point in its > > lifetime cannot be also doing exec(). > > > > What if it's one of those kthreads created by directly invoking > kernel_thread()? AFAICT right now it's only umh, and that one does execve() > so it ends up stripped of PF_KTHREAD. It could however go through an error > path, i.e. not call exec, and exit, giving us: > > put_task_struct(p) > `\ > free_task(p) > `\ > if (tsk->flags & PF_KTHREAD) > free_kthread_struct(tsk); > `\ > to_kthread(p) I'm not following, at the point we hit free_task() it had better be dead and p->flags had better be stable. Either it will, or will not, have PF_KTHREAD.
Re: [syzbot] WARNING in kthread_is_per_cpu
On 20/04/21 10:51, Peter Zijlstra wrote: > On Mon, Apr 19, 2021 at 08:58:26PM +0100, Valentin Schneider wrote: > >> Looks about right, IIUC the key being: >> >> p->flags & PF_KTHREAD + p->set_child_tid => the struct kthread is >> persistent >> >> p->flags & PF_KTHREAD => you may or may not have a struct kthread (see >> kernel/umh.c kernel_thread() uses). PF_KTHREAD isn't even guaranteed to >> persist (begin_new_exec()), which seems to be what the syzbot hit. > > Ack, that's nicely put. > >> While we're at it, does free_kthread_struct() want the __to_kthread() >> treatment as well? The other to_kthread() callsites looked like they only >> made sense with a "proper" kthread anyway. > > I think free_kthread_struct() is ok, because a task at that point in its > lifetime cannot be also doing exec(). > What if it's one of those kthreads created by directly invoking kernel_thread()? AFAICT right now it's only umh, and that one does execve() so it ends up stripped of PF_KTHREAD. It could however go through an error path, i.e. not call exec, and exit, giving us: put_task_struct(p) `\ free_task(p) `\ if (tsk->flags & PF_KTHREAD) free_kthread_struct(tsk); `\ to_kthread(p) > kthread_func() is another 'fun' trainwreck waiting to happen -- luckily > the only caller uses current, still let me go fix it. > > kthread_probe_data() relies on PF_WQ_WORKER implying PF_KTHREAD but > otherwise seems very fragile too. > > Something like so then? > Other than the above: Reviewed-by: Valentin Schneider
Re: [syzbot] WARNING in kthread_is_per_cpu
On Mon, Apr 19, 2021 at 08:58:26PM +0100, Valentin Schneider wrote:
> Looks about right, IIUC the key being:
>
> p->flags & PF_KTHREAD + p->set_child_tid => the struct kthread is
> persistent
>
> p->flags & PF_KTHREAD => you may or may not have a struct kthread (see
> kernel/umh.c kernel_thread() uses). PF_KTHREAD isn't even guaranteed to
> persist (begin_new_exec()), which seems to be what the syzbot hit.
Ack, that's nicely put.
> While we're at it, does free_kthread_struct() want the __to_kthread()
> treatment as well? The other to_kthread() callsites looked like they only
> made sense with a "proper" kthread anyway.
I think free_kthread_struct() is ok, because a task at that point in its
lifetime cannot be also doing exec().
kthread_func() is another 'fun' trainwreck waiting to happen -- luckily
the only caller uses current, still let me go fix it.
kthread_probe_data() relies on PF_WQ_WORKER implying PF_KTHREAD but
otherwise seems very fragile too.
Something like so then?
---
Subject: kthread: Fix PF_KTHREAD vs to_kthread() race
From: Peter Zijlstra
Date: Tue Apr 20 10:18:17 CEST 2021
The kthread_is_per_cpu() construct relies on only being called on
PF_KTHREAD tasks (per the WARN in to_kthread). This gives rise to the
following usage pattern:
if ((p->flags & PF_KTHREAD) && kthread_is_per_cpu(p))
However, as reported by syzcaller, this is broken. The scenario is:
CPU0CPU1 (running p)
(p->flags & PF_KTHREAD) // true
begin_new_exec()
me->flags &= ~(PF_KTHREAD|...);
kthread_is_per_cpu(p)
to_kthread(p)
WARN(!(p->flags & PF_KTHREAD) <-- *SPLAT*
Introduce __to_kthread() that omits the WARN and is sure to check both
values.
Use this to remove the problematic pattern for kthread_is_per_cpu()
and fix a number of other kthread_*() functions that have similar
issues but are currently not used in ways that would expose the
problem.
Notably kthread_func() is only ever called on 'current', while
kthread_probe_data() is only used for PF_WQ_WORKER, which implies the
task is from kthread_create*().
Fixes: ac687e6e8c26 ("kthread: Extract KTHREAD_IS_PER_CPU")
Signed-off-by: Peter Zijlstra (Intel)
---
kernel/kthread.c| 33 +++--
kernel/sched/core.c |2 +-
kernel/sched/fair.c |2 +-
3 files changed, 29 insertions(+), 8 deletions(-)
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -84,6 +84,25 @@ static inline struct kthread *to_kthread
return (__force void *)k->set_child_tid;
}
+/*
+ * Variant of to_kthread() that doesn't assume @p is a kthread.
+ *
+ * Per construction; when:
+ *
+ * (p->flags & PF_KTHREAD) && p->set_child_tid
+ *
+ * the task is both a kthread and struct kthread is persistent. However
+ * PF_KTHREAD on it's own is not, kernel_thread() can exec() (See umh.c and
+ * begin_new_exec()).
+ */
+static inline struct kthread *__to_kthread(struct task_struct *p)
+{
+ void *kthread = (__force void *)p->set_child_tid;
+ if (kthread && !(p->flags & PF_KTHREAD))
+ kthread = NULL;
+ return kthread;
+}
+
void free_kthread_struct(struct task_struct *k)
{
struct kthread *kthread;
@@ -168,8 +187,9 @@ EXPORT_SYMBOL_GPL(kthread_freezable_shou
*/
void *kthread_func(struct task_struct *task)
{
- if (task->flags & PF_KTHREAD)
- return to_kthread(task)->threadfn;
+ struct kthread *kthread = __to_kthread(task);
+ if (kthread)
+ return kthread->threadfn;
return NULL;
}
EXPORT_SYMBOL_GPL(kthread_func);
@@ -199,10 +219,11 @@ EXPORT_SYMBOL_GPL(kthread_data);
*/
void *kthread_probe_data(struct task_struct *task)
{
- struct kthread *kthread = to_kthread(task);
+ struct kthread *kthread = __to_kthread(task);
void *data = NULL;
- copy_from_kernel_nofault(, >data, sizeof(data));
+ if (kthread)
+ copy_from_kernel_nofault(, >data, sizeof(data));
return data;
}
@@ -514,9 +535,9 @@ void kthread_set_per_cpu(struct task_str
set_bit(KTHREAD_IS_PER_CPU, >flags);
}
-bool kthread_is_per_cpu(struct task_struct *k)
+bool kthread_is_per_cpu(struct task_struct *p)
{
- struct kthread *kthread = to_kthread(k);
+ struct kthread *kthread = __to_kthread(p);
if (!kthread)
return false;
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -8505,7 +8505,7 @@ static void balance_push(struct rq *rq)
* histerical raisins.
*/
if (rq->idle == push_task ||
- ((push_task->flags & PF_KTHREAD) && kthread_is_per_cpu(push_task))
||
+ kthread_is_per_cpu(push_task) ||
is_migration_disabled(push_task)) {
/*
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -7619,7 +7619,7 @@ int can_migrate_task(struct task_struct
Re: [syzbot] WARNING in kthread_is_per_cpu
On 19/04/21 20:45, Peter Zijlstra wrote:
> On Mon, Apr 19, 2021 at 12:31:22PM +0100, Valentin Schneider wrote:
>
>> if ((p->flags & PF_KTHREAD) && kthread_is_per_cpu(p))
>> `\
>>to_kthread(p);
>> `\
>> WARN_ON(!(p->flags & PF_KTHREAD));
>>
>> ... Huh?
>
> Something like so perhaps?
>
Looks about right, IIUC the key being:
p->flags & PF_KTHREAD + p->set_child_tid => the struct kthread is
persistent
p->flags & PF_KTHREAD => you may or may not have a struct kthread (see
kernel/umh.c kernel_thread() uses). PF_KTHREAD isn't even guaranteed to
persist (begin_new_exec()), which seems to be what the syzbot hit.
I'd be happy to see is_per_cpu_kthread() die, but that's somewhat
orthogonal to this here. For now, this does need the tiny extra below.
While we're at it, does free_kthread_struct() want the __to_kthread()
treatment as well? The other to_kthread() callsites looked like they only
made sense with a "proper" kthread anyway.
---
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 49636a49843f..8b470c2d5680 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -7612,7 +7612,7 @@ int can_migrate_task(struct task_struct *p, struct lb_env
*env)
return 0;
/* Disregard pcpu kthreads; they are where they need to be. */
- if ((p->flags & PF_KTHREAD) && kthread_is_per_cpu(p))
+ if (kthread_is_per_cpu(p))
return 0;
if (!cpumask_test_cpu(env->dst_cpu, p->cpus_ptr)) {
> diff --git a/kernel/kthread.c b/kernel/kthread.c
> index 1578973c5740..eeba40df61ac 100644
> --- a/kernel/kthread.c
> +++ b/kernel/kthread.c
> @@ -78,6 +78,14 @@ static inline void set_kthread_struct(void *kthread)
> current->set_child_tid = (__force void __user *)kthread;
> }
>
> +static inline struct kthread *__to_kthread(struct task_struct *k)
> +{
> + void *kthread = (__force void *)k->set_child_tid;
> + if (kthread && !(k->flags & PF_KTHREAD))
> + kthread = NULL;
> + return kthread;
> +}
> +
> static inline struct kthread *to_kthread(struct task_struct *k)
> {
> WARN_ON(!(k->flags & PF_KTHREAD));
> @@ -516,7 +524,7 @@ void kthread_set_per_cpu(struct task_struct *k, int cpu)
>
> bool kthread_is_per_cpu(struct task_struct *k)
> {
> - struct kthread *kthread = to_kthread(k);
> + struct kthread *kthread = __to_kthread(k);
> if (!kthread)
> return false;
>
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index 3384ea74cad4..dc6311bd6986 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -7658,7 +7658,7 @@ static void balance_push(struct rq *rq)
>* histerical raisins.
>*/
> if (rq->idle == push_task ||
> - ((push_task->flags & PF_KTHREAD) && kthread_is_per_cpu(push_task))
> ||
> + kthread_is_per_cpu(push_task) ||
> is_migration_disabled(push_task)) {
>
> /*
Re: [syzbot] WARNING in kthread_is_per_cpu
On Mon, Apr 19, 2021 at 12:31:22PM +0100, Valentin Schneider wrote:
> if ((p->flags & PF_KTHREAD) && kthread_is_per_cpu(p))
> `\
>to_kthread(p);
> `\
> WARN_ON(!(p->flags & PF_KTHREAD));
>
> ... Huh?
Something like so perhaps?
diff --git a/kernel/kthread.c b/kernel/kthread.c
index 1578973c5740..eeba40df61ac 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -78,6 +78,14 @@ static inline void set_kthread_struct(void *kthread)
current->set_child_tid = (__force void __user *)kthread;
}
+static inline struct kthread *__to_kthread(struct task_struct *k)
+{
+ void *kthread = (__force void *)k->set_child_tid;
+ if (kthread && !(k->flags & PF_KTHREAD))
+ kthread = NULL;
+ return kthread;
+}
+
static inline struct kthread *to_kthread(struct task_struct *k)
{
WARN_ON(!(k->flags & PF_KTHREAD));
@@ -516,7 +524,7 @@ void kthread_set_per_cpu(struct task_struct *k, int cpu)
bool kthread_is_per_cpu(struct task_struct *k)
{
- struct kthread *kthread = to_kthread(k);
+ struct kthread *kthread = __to_kthread(k);
if (!kthread)
return false;
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 3384ea74cad4..dc6311bd6986 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7658,7 +7658,7 @@ static void balance_push(struct rq *rq)
* histerical raisins.
*/
if (rq->idle == push_task ||
- ((push_task->flags & PF_KTHREAD) && kthread_is_per_cpu(push_task))
||
+ kthread_is_per_cpu(push_task) ||
is_migration_disabled(push_task)) {
/*
Re: [syzbot] WARNING in kthread_is_per_cpu
On 19/04/21 03:36, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit:1216f02e Add linux-next specific files for 20210415 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=1032ba29d0 > kernel config: https://syzkaller.appspot.com/x/.config?x=3491b04113499f81 > dashboard link: https://syzkaller.appspot.com/bug?extid=9362b31a2e0cad8b749d > > Unfortunately, I don't have any reproducer for this issue yet. > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+9362b31a2e0cad8b7...@syzkaller.appspotmail.com > > [ cut here ] > WARNING: CPU: 1 PID: 23550 at kernel/kthread.c:83 to_kthread > kernel/kthread.c:83 [inline] > WARNING: CPU: 1 PID: 23550 at kernel/kthread.c:83 > kthread_is_per_cpu+0xc4/0xf0 kernel/kthread.c:519 > Modules linked in: > CPU: 1 PID: 23550 Comm: syz-executor.3 Not tainted > 5.12.0-rc7-next-20210415-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > RIP: 0010:to_kthread kernel/kthread.c:83 [inline] > RIP: 0010:kthread_is_per_cpu+0xc4/0xf0 kernel/kthread.c:519 > Code: 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 2e 4c 8b 23 41 83 e4 01 > e8 89 d3 27 00 44 89 e0 5b 5d 41 5c c3 e8 7c d3 27 00 <0f> 0b eb 88 e8 33 90 > 6c 00 e9 68 ff ff ff e8 39 90 6c 00 eb 9a 48 > RSP: 0018:c9dc0c08 EFLAGS: 00010046 > RAX: RBX: 88802533d580 RCX: 0100 > RDX: 8880549bb900 RSI: 814ca4c4 RDI: 0003 > RBP: R08: R09: 88802533d580 > R10: 814ca44c R11: 018a3b90 R12: 0001 > R13: c9dc0d90 R14: 0001 R15: 88802533d580 > FS: 7f4be57d3700() GS:8880b9d0() knlGS: > CS: 0010 DS: ES: CR0: 80050033 > CR2: 001b2cd24000 CR3: 24626000 CR4: 001506e0 > DR0: DR1: DR2: > DR3: DR6: fffe0ff0 DR7: 0400 > Call Trace: > > can_migrate_task+0x124/0x1630 kernel/sched/fair.c:7610 > detach_tasks kernel/sched/fair.c:7774 [inline] > load_balance+0xc72/0x2730 kernel/sched/fair.c:9696 > rebalance_domains+0x668/0xda0 kernel/sched/fair.c:10075 > __do_softirq+0x29b/0x9fe kernel/softirq.c:559 > invoke_softirq kernel/softirq.c:433 [inline] > __irq_exit_rcu+0x136/0x200 kernel/softirq.c:637 > irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 > sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1100 > > asm_sysvec_apic_timer_interrupt+0x12/0x20 > arch/x86/include/asm/idtentry.h:632 if ((p->flags & PF_KTHREAD) && kthread_is_per_cpu(p)) `\ to_kthread(p); `\ WARN_ON(!(p->flags & PF_KTHREAD)); ... Huh?
Re: [syzbot] WARNING in kthread_is_per_cpu
On Mon, Apr 19 2021 at 03:36, syzbot wrote: > Hello, > > syzbot found the following issue on: > > HEAD commit:1216f02e Add linux-next specific files for 20210415 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=1032ba29d0 > kernel config: https://syzkaller.appspot.com/x/.config?x=3491b04113499f81 > dashboard link: https://syzkaller.appspot.com/bug?extid=9362b31a2e0cad8b749d > > Unfortunately, I don't have any reproducer for this issue yet. > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+9362b31a2e0cad8b7...@syzkaller.appspotmail.com > > [ cut here ] > WARNING: CPU: 1 PID: 23550 at kernel/kthread.c:83 to_kthread > kernel/kthread.c:83 [inline] > WARNING: CPU: 1 PID: 23550 at kernel/kthread.c:83 > kthread_is_per_cpu+0xc4/0xf0 kernel/kthread.c:519 > Modules linked in: > CPU: 1 PID: 23550 Comm: syz-executor.3 Not tainted > 5.12.0-rc7-next-20210415-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > RIP: 0010:to_kthread kernel/kthread.c:83 [inline] > RIP: 0010:kthread_is_per_cpu+0xc4/0xf0 kernel/kthread.c:519 > Code: 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 2e 4c 8b 23 41 83 e4 01 > e8 89 d3 27 00 44 89 e0 5b 5d 41 5c c3 e8 7c d3 27 00 <0f> 0b eb 88 e8 33 90 > 6c 00 e9 68 ff ff ff e8 39 90 6c 00 eb 9a 48 > RSP: 0018:c9dc0c08 EFLAGS: 00010046 > RAX: RBX: 88802533d580 RCX: 0100 > RDX: 8880549bb900 RSI: 814ca4c4 RDI: 0003 > RBP: R08: R09: 88802533d580 > R10: 814ca44c R11: 018a3b90 R12: 0001 > R13: c9dc0d90 R14: 0001 R15: 88802533d580 > FS: 7f4be57d3700() GS:8880b9d0() knlGS: > CS: 0010 DS: ES: CR0: 80050033 > CR2: 001b2cd24000 CR3: 24626000 CR4: 001506e0 > DR0: DR1: DR2: > DR3: DR6: fffe0ff0 DR7: 0400 > Call Trace: > > can_migrate_task+0x124/0x1630 kernel/sched/fair.c:7610 So this is: if ((p->flags & PF_KTHREAD) && kthread_is_per_cpu(p)) The warning in to_kthread() is: WARN_ON(!(k->flags & PF_KTHREAD)); IOW, the p>flags lost PF_KTHREAD within at max. 50 instructions. Magic, cosmic rays or memory corruption / stray pointer in some other place? Thanks, tglx
[syzbot] WARNING in kthread_is_per_cpu
Hello, syzbot found the following issue on: HEAD commit:1216f02e Add linux-next specific files for 20210415 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=1032ba29d0 kernel config: https://syzkaller.appspot.com/x/.config?x=3491b04113499f81 dashboard link: https://syzkaller.appspot.com/bug?extid=9362b31a2e0cad8b749d Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+9362b31a2e0cad8b7...@syzkaller.appspotmail.com [ cut here ] WARNING: CPU: 1 PID: 23550 at kernel/kthread.c:83 to_kthread kernel/kthread.c:83 [inline] WARNING: CPU: 1 PID: 23550 at kernel/kthread.c:83 kthread_is_per_cpu+0xc4/0xf0 kernel/kthread.c:519 Modules linked in: CPU: 1 PID: 23550 Comm: syz-executor.3 Not tainted 5.12.0-rc7-next-20210415-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:to_kthread kernel/kthread.c:83 [inline] RIP: 0010:kthread_is_per_cpu+0xc4/0xf0 kernel/kthread.c:519 Code: 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 00 75 2e 4c 8b 23 41 83 e4 01 e8 89 d3 27 00 44 89 e0 5b 5d 41 5c c3 e8 7c d3 27 00 <0f> 0b eb 88 e8 33 90 6c 00 e9 68 ff ff ff e8 39 90 6c 00 eb 9a 48 RSP: 0018:c9dc0c08 EFLAGS: 00010046 RAX: RBX: 88802533d580 RCX: 0100 RDX: 8880549bb900 RSI: 814ca4c4 RDI: 0003 RBP: R08: R09: 88802533d580 R10: 814ca44c R11: 018a3b90 R12: 0001 R13: c9dc0d90 R14: 0001 R15: 88802533d580 FS: 7f4be57d3700() GS:8880b9d0() knlGS: CS: 0010 DS: ES: CR0: 80050033 CR2: 001b2cd24000 CR3: 24626000 CR4: 001506e0 DR0: DR1: DR2: DR3: DR6: fffe0ff0 DR7: 0400 Call Trace: can_migrate_task+0x124/0x1630 kernel/sched/fair.c:7610 detach_tasks kernel/sched/fair.c:7774 [inline] load_balance+0xc72/0x2730 kernel/sched/fair.c:9696 rebalance_domains+0x668/0xda0 kernel/sched/fair.c:10075 __do_softirq+0x29b/0x9fe kernel/softirq.c:559 invoke_softirq kernel/softirq.c:433 [inline] __irq_exit_rcu+0x136/0x200 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:191 Code: 74 24 10 e8 5a 05 46 f8 48 89 ef e8 f2 7d 46 f8 81 e3 00 02 00 00 75 25 9c 58 f6 c4 02 75 2d 48 85 db 74 01 fb bf 01 00 00 00 e3 83 3a f8 65 8b 05 cc e4 ed 76 85 c0 74 0a 5b 5d c3 e8 20 73 RSP: 0018:c90001c0ef30 EFLAGS: 0206 RAX: 0006 RBX: 0200 RCX: 11fbdad2 RDX: RSI: 0001 RDI: 0001 RBP: 8c076c20 R08: 0001 R09: 8fdeb8a7 R10: 0001 R11: R12: R13: 000c R14: 0002 R15: 0008f9b0 spin_unlock_irqrestore include/linux/spinlock.h:414 [inline] pcpu_alloc+0x4f7/0x17a0 mm/percpu.c:1807 vlan_dev_init+0x9f9/0xe70 net/8021q/vlan_dev.c:614 register_netdevice+0x51e/0x1500 net/core/dev.c:10188 register_vlan_dev+0x360/0x960 net/8021q/vlan.c:179 vlan_newlink+0x477/0x700 net/8021q/vlan_netlink.c:187 __rtnl_newlink+0x1062/0x1710 net/core/rtnetlink.c:3452 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3500 rtnetlink_rcv_msg+0x413/0xaf0 net/core/rtnetlink.c:5562 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2502 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1338 netlink_sendmsg+0x84c/0xd90 net/netlink/af_netlink.c:1927 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:674 sys_sendmsg+0x6e8/0x810 net/socket.c:2350 ___sys_sendmsg+0xf3/0x170 net/socket.c:2404 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2433 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x466459 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:7f4be57d3188 EFLAGS: 0246 ORIG_RAX: 002e RAX: ffda RBX: 0056bf60 RCX: 00466459 RDX: 0810 RSI: 2000 RDI: 0006 RBP: 004bf9fb R08: R09: R10: R11: 0246 R12: 0056bf60 R13: 7ffc92da70af R14: 7f4be57d3300 R15: 00022000 --- This report is
