Re: BUG: sleeping function called from invalid context in __alloc_pages_nodemask

Re: BUG: sleeping function called from invalid context in __alloc_pages_nodemask

[Hillf Danton]

On Fri, 29 Nov 2019 23:35:08 -0800
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:    419593da Add linux-next specific files for 20191129
> git tree:       linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=12cc369ce00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=7c04b0959e75c206
> dashboard link: https://syzkaller.appspot.com/bug?extid=4925d60532bf4c399608
> compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> 
> Unfortunately, I don't have any reproducer for this crash yet.
> 
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+4925d60532bf4c399608@syzkaller.appspotmail.com
> 
> BUG: sleeping function called from invalid context at mm/page_alloc.c:4681
> in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2710, name:  
> kworker/0:2
> 4 locks held by kworker/0:2/2710:
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: __write_once_size  
> include/linux/compiler.h:247 [inline]
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: arch_atomic64_set  
> arch/x86/include/asm/atomic64_64.h:34 [inline]
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: atomic64_set  
> include/asm-generic/atomic-instrumented.h:868 [inline]
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: atomic_long_set  
> include/asm-generic/atomic-long.h:40 [inline]
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: set_work_data  
> kernel/workqueue.c:615 [inline]
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at:  
> set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline]
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at:  
> process_one_work+0x88b/0x1740 kernel/workqueue.c:2235
>   #1: ffffc9000802fdc0 (pcpu_balance_work){+.+.}, at:  
> process_one_work+0x8c1/0x1740 kernel/workqueue.c:2239
>   #2: ffffffff8983ff20 (pcpu_alloc_mutex){+.+.}, at:  
> pcpu_balance_workfn+0xb7/0x1310 mm/percpu.c:1845
>   #3: ffffffff89851b18 (vmap_area_lock){+.+.}, at: spin_lock  
> include/linux/spinlock.h:338 [inline]
>   #3: ffffffff89851b18 (vmap_area_lock){+.+.}, at:  
> pcpu_get_vm_areas+0x3b27/0x3f00 mm/vmalloc.c:3431
> Preemption disabled at:
> [<ffffffff81a89ce7>] spin_lock include/linux/spinlock.h:338 [inline]
> [<ffffffff81a89ce7>] pcpu_get_vm_areas+0x3b27/0x3f00 mm/vmalloc.c:3431
> CPU: 0 PID: 2710 Comm: kworker/0:2 Not tainted  
> 5.4.0-next-20191129-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
> Google 01/01/2011
> Workqueue: events pcpu_balance_workfn
> Call Trace:
>   __dump_stack lib/dump_stack.c:77 [inline]
>   dump_stack+0x197/0x210 lib/dump_stack.c:118
>   ___might_sleep.cold+0x1fb/0x23e kernel/sched/core.c:6800
>   __might_sleep+0x95/0x190 kernel/sched/core.c:6753
>   prepare_alloc_pages mm/page_alloc.c:4681 [inline]
>   __alloc_pages_nodemask+0x523/0x910 mm/page_alloc.c:4730
>   alloc_pages_current+0x107/0x210 mm/mempolicy.c:2211
>   alloc_pages include/linux/gfp.h:532 [inline]
>   __get_free_pages+0xc/0x40 mm/page_alloc.c:4786
>   kasan_populate_vmalloc_pte mm/kasan/common.c:762 [inline]
>   kasan_populate_vmalloc_pte+0x2f/0x1c0 mm/kasan/common.c:753
>   apply_to_pte_range mm/memory.c:2041 [inline]
>   apply_to_pmd_range mm/memory.c:2068 [inline]
>   apply_to_pud_range mm/memory.c:2088 [inline]
>   apply_to_p4d_range mm/memory.c:2108 [inline]
>   apply_to_page_range+0x445/0x700 mm/memory.c:2133
>   kasan_populate_vmalloc+0x68/0x90 mm/kasan/common.c:791
>   pcpu_get_vm_areas+0x3c77/0x3f00 mm/vmalloc.c:3439
>   pcpu_create_chunk+0x24e/0x7f0 mm/percpu-vm.c:340
>   pcpu_balance_workfn+0xf1b/0x1310 mm/percpu.c:1934
>   process_one_work+0x9af/0x1740 kernel/workqueue.c:2264
>   worker_thread+0x98/0xe40 kernel/workqueue.c:2410
>   kthread+0x361/0x430 kernel/kthread.c:255
>   ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Replace the blocking gfp mask with a non-blocking one to survive
checks like might_sleep.

--- a/mm/kasan/common.c
+++ b/mm/kasan/common.c
@@ -759,7 +759,7 @@ static int kasan_populate_vmalloc_pte(pt
 	if (likely(!pte_none(*ptep)))
 		return 0;
 
-	page = __get_free_page(GFP_KERNEL);
+	page = __get_free_page(GFP_NOWAIT);
 	if (!page)
 		return -ENOMEM;
 

BUG: sleeping function called from invalid context in __alloc_pages_nodemask

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    419593da Add linux-next specific files for 20191129
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=12cc369ce00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7c04b0959e75c206
dashboard link: https://syzkaller.appspot.com/bug?extid=4925d60532bf4c399608
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+4925d60532bf4c399608@syzkaller.appspotmail.com

BUG: sleeping function called from invalid context at mm/page_alloc.c:4681
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2710, name:  
kworker/0:2
4 locks held by kworker/0:2/2710:
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: __write_once_size  
include/linux/compiler.h:247 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: arch_atomic64_set  
arch/x86/include/asm/atomic64_64.h:34 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: atomic64_set  
include/asm-generic/atomic-instrumented.h:868 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: atomic_long_set  
include/asm-generic/atomic-long.h:40 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: set_work_data  
kernel/workqueue.c:615 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at:  
set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at:  
process_one_work+0x88b/0x1740 kernel/workqueue.c:2235
  #1: ffffc9000802fdc0 (pcpu_balance_work){+.+.}, at:  
process_one_work+0x8c1/0x1740 kernel/workqueue.c:2239
  #2: ffffffff8983ff20 (pcpu_alloc_mutex){+.+.}, at:  
pcpu_balance_workfn+0xb7/0x1310 mm/percpu.c:1845
  #3: ffffffff89851b18 (vmap_area_lock){+.+.}, at: spin_lock  
include/linux/spinlock.h:338 [inline]
  #3: ffffffff89851b18 (vmap_area_lock){+.+.}, at:  
pcpu_get_vm_areas+0x3b27/0x3f00 mm/vmalloc.c:3431
Preemption disabled at:
[<ffffffff81a89ce7>] spin_lock include/linux/spinlock.h:338 [inline]
[<ffffffff81a89ce7>] pcpu_get_vm_areas+0x3b27/0x3f00 mm/vmalloc.c:3431
CPU: 0 PID: 2710 Comm: kworker/0:2 Not tainted  
5.4.0-next-20191129-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Workqueue: events pcpu_balance_workfn
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0x197/0x210 lib/dump_stack.c:118
  ___might_sleep.cold+0x1fb/0x23e kernel/sched/core.c:6800
  __might_sleep+0x95/0x190 kernel/sched/core.c:6753
  prepare_alloc_pages mm/page_alloc.c:4681 [inline]
  __alloc_pages_nodemask+0x523/0x910 mm/page_alloc.c:4730
  alloc_pages_current+0x107/0x210 mm/mempolicy.c:2211
  alloc_pages include/linux/gfp.h:532 [inline]
  __get_free_pages+0xc/0x40 mm/page_alloc.c:4786
  kasan_populate_vmalloc_pte mm/kasan/common.c:762 [inline]
  kasan_populate_vmalloc_pte+0x2f/0x1c0 mm/kasan/common.c:753
  apply_to_pte_range mm/memory.c:2041 [inline]
  apply_to_pmd_range mm/memory.c:2068 [inline]
  apply_to_pud_range mm/memory.c:2088 [inline]
  apply_to_p4d_range mm/memory.c:2108 [inline]
  apply_to_page_range+0x445/0x700 mm/memory.c:2133
  kasan_populate_vmalloc+0x68/0x90 mm/kasan/common.c:791
  pcpu_get_vm_areas+0x3c77/0x3f00 mm/vmalloc.c:3439
  pcpu_create_chunk+0x24e/0x7f0 mm/percpu-vm.c:340
  pcpu_balance_workfn+0xf1b/0x1310 mm/percpu.c:1934
  process_one_work+0x9af/0x1740 kernel/workqueue.c:2264
  worker_thread+0x98/0xe40 kernel/workqueue.c:2410
  kthread+0x361/0x430 kernel/kthread.c:255
  ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352


---
This bug 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 bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

Re: BUG: sleeping function called from invalid context in __alloc_pages_nodemask

[Dmitry Vyukov]

On Sat, Nov 30, 2019 at 8:35 AM syzbot
<syzbot+4925d60532bf4c399608@syzkaller.appspotmail.com> wrote:
>
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit:    419593da Add linux-next specific files for 20191129
> git tree:       linux-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=12cc369ce00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=7c04b0959e75c206
> dashboard link: https://syzkaller.appspot.com/bug?extid=4925d60532bf4c399608
> compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
>
> Unfortunately, I don't have any reproducer for this crash yet.
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+4925d60532bf4c399608@syzkaller.appspotmail.com

+Daniel, kasan-dev
This is presumably from the new CONFIG_KASAN_VMALLOC

> BUG: sleeping function called from invalid context at mm/page_alloc.c:4681
> in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2710, name:
> kworker/0:2
> 4 locks held by kworker/0:2/2710:
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: __write_once_size
> include/linux/compiler.h:247 [inline]
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: arch_atomic64_set
> arch/x86/include/asm/atomic64_64.h:34 [inline]
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: atomic64_set
> include/asm-generic/atomic-instrumented.h:868 [inline]
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: atomic_long_set
> include/asm-generic/atomic-long.h:40 [inline]
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: set_work_data
> kernel/workqueue.c:615 [inline]
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at:
> set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline]
>   #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at:
> process_one_work+0x88b/0x1740 kernel/workqueue.c:2235
>   #1: ffffc9000802fdc0 (pcpu_balance_work){+.+.}, at:
> process_one_work+0x8c1/0x1740 kernel/workqueue.c:2239
>   #2: ffffffff8983ff20 (pcpu_alloc_mutex){+.+.}, at:
> pcpu_balance_workfn+0xb7/0x1310 mm/percpu.c:1845
>   #3: ffffffff89851b18 (vmap_area_lock){+.+.}, at: spin_lock
> include/linux/spinlock.h:338 [inline]
>   #3: ffffffff89851b18 (vmap_area_lock){+.+.}, at:
> pcpu_get_vm_areas+0x3b27/0x3f00 mm/vmalloc.c:3431
> Preemption disabled at:
> [<ffffffff81a89ce7>] spin_lock include/linux/spinlock.h:338 [inline]
> [<ffffffff81a89ce7>] pcpu_get_vm_areas+0x3b27/0x3f00 mm/vmalloc.c:3431
> CPU: 0 PID: 2710 Comm: kworker/0:2 Not tainted
> 5.4.0-next-20191129-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> Workqueue: events pcpu_balance_workfn
> Call Trace:
>   __dump_stack lib/dump_stack.c:77 [inline]
>   dump_stack+0x197/0x210 lib/dump_stack.c:118
>   ___might_sleep.cold+0x1fb/0x23e kernel/sched/core.c:6800
>   __might_sleep+0x95/0x190 kernel/sched/core.c:6753
>   prepare_alloc_pages mm/page_alloc.c:4681 [inline]
>   __alloc_pages_nodemask+0x523/0x910 mm/page_alloc.c:4730
>   alloc_pages_current+0x107/0x210 mm/mempolicy.c:2211
>   alloc_pages include/linux/gfp.h:532 [inline]
>   __get_free_pages+0xc/0x40 mm/page_alloc.c:4786
>   kasan_populate_vmalloc_pte mm/kasan/common.c:762 [inline]
>   kasan_populate_vmalloc_pte+0x2f/0x1c0 mm/kasan/common.c:753
>   apply_to_pte_range mm/memory.c:2041 [inline]
>   apply_to_pmd_range mm/memory.c:2068 [inline]
>   apply_to_pud_range mm/memory.c:2088 [inline]
>   apply_to_p4d_range mm/memory.c:2108 [inline]
>   apply_to_page_range+0x445/0x700 mm/memory.c:2133
>   kasan_populate_vmalloc+0x68/0x90 mm/kasan/common.c:791
>   pcpu_get_vm_areas+0x3c77/0x3f00 mm/vmalloc.c:3439
>   pcpu_create_chunk+0x24e/0x7f0 mm/percpu-vm.c:340
>   pcpu_balance_workfn+0xf1b/0x1310 mm/percpu.c:1934
>   process_one_work+0x9af/0x1740 kernel/workqueue.c:2264
>   worker_thread+0x98/0xe40 kernel/workqueue.c:2410
>   kthread+0x361/0x430 kernel/kthread.c:255
>   ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
>
>
> ---
> This bug 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 bug report. See:
> https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
>
> --
> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group.
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Re: BUG: sleeping function called from invalid context in __alloc_pages_nodemask

[Uladzislau Rezki]

On Sat, Nov 30, 2019 at 09:48:34PM +0900, Tetsuo Handa wrote:
> On 2019/11/30 16:57, Dmitry Vyukov wrote:
> > On Sat, Nov 30, 2019 at 8:35 AM syzbot
> > <syzbot+4925d60532bf4c399608@syzkaller.appspotmail.com> wrote:
> >>
> >> Hello,
> >>
> >> syzbot found the following crash on:
> >>
> >> HEAD commit:    419593da Add linux-next specific files for 20191129
> >> git tree:       linux-next
> >> console output: https://syzkaller.appspot.com/x/log.txt?x=12cc369ce00000
> >> kernel config:  https://syzkaller.appspot.com/x/.config?x=7c04b0959e75c206
> >> dashboard link: https://syzkaller.appspot.com/bug?extid=4925d60532bf4c399608
> >> compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
> >>
> >> Unfortunately, I don't have any reproducer for this crash yet.
> >>
> >> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> >> Reported-by: syzbot+4925d60532bf4c399608@syzkaller.appspotmail.com
> > 
> > +Daniel, kasan-dev
> > This is presumably from the new CONFIG_KASAN_VMALLOC
> 
> Well, this is because
> 
> commit d005e4cdb2307f63b5ce5cb359964c5a72d95790
> Author: Uladzislau Rezki (Sony) <urezki@gmail.com>
> Date:   Tue Nov 19 11:45:23 2019 +1100
> 
>     mm/vmalloc: rework vmap_area_lock
> 
> @@ -3363,29 +3369,38 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
>                 va = vas[area];
>                 va->va_start = start;
>                 va->va_end = start + size;
> -
> -               insert_vmap_area(va, &vmap_area_root, &vmap_area_list);
>         }
> 
> -       spin_unlock(&vmap_area_lock);
> +       spin_unlock(&free_vmap_area_lock);
> 
>         /* insert all vm's */
> -       for (area = 0; area < nr_vms; area++)
> -               setup_vmalloc_vm(vms[area], vas[area], VM_ALLOC,
> +       spin_lock(&vmap_area_lock);
> +       for (area = 0; area < nr_vms; area++) {
> +               insert_vmap_area(vas[area], &vmap_area_root, &vmap_area_list);
> +
> +               setup_vmalloc_vm_locked(vms[area], vas[area], VM_ALLOC,
>                                  pcpu_get_vm_areas);
> +       }
> +       spin_unlock(&vmap_area_lock);
> 
>         kfree(vas);
>         return vms;
> 
> made the iteration atomic context while
> 
> commit 1800fa0a084c60a600be0cc43fc657ba5609fdda
> Author: Daniel Axtens <dja@axtens.net>
> Date:   Tue Nov 19 11:45:23 2019 +1100
> 
>     kasan: support backing vmalloc space with real shadow memory
> 
> @@ -3380,6 +3414,9 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets,
> 
>                 setup_vmalloc_vm_locked(vms[area], vas[area], VM_ALLOC,
>                                  pcpu_get_vm_areas);
> +
> +               /* assume success here */
> +               kasan_populate_vmalloc(sizes[area], vms[area]);
>         }
>         spin_unlock(&vmap_area_lock);
> 
> tried to do sleeping allocation inside the iteration.
There was a patch that fixes an attempt of "sleeping allocation" under
the spinlock from Daniel:

https://lkml.org/lkml/2019/11/20/22

--
Vlad Rezki

Re: BUG: sleeping function called from invalid context in __alloc_pages_nodemask

[syzbot]

syzbot has found a reproducer for the following crash on:

HEAD commit:    419593da Add linux-next specific files for 20191129
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=168e202ee00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7c04b0959e75c206
dashboard link: https://syzkaller.appspot.com/bug?extid=4925d60532bf4c399608
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=162234a2e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+4925d60532bf4c399608@syzkaller.appspotmail.com

BUG: sleeping function called from invalid context at mm/page_alloc.c:4681
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 9071, name:  
kworker/0:3
4 locks held by kworker/0:3/9071:
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: __write_once_size  
include/linux/compiler.h:247 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: arch_atomic64_set  
arch/x86/include/asm/atomic64_64.h:34 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: atomic64_set  
include/asm-generic/atomic-instrumented.h:868 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: atomic_long_set  
include/asm-generic/atomic-long.h:40 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: set_work_data  
kernel/workqueue.c:615 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at:  
set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at:  
process_one_work+0x88b/0x1740 kernel/workqueue.c:2235
  #1: ffffc900021a7dc0 (pcpu_balance_work){+.+.}, at:  
process_one_work+0x8c1/0x1740 kernel/workqueue.c:2239
  #2: ffffffff8983ff20 (pcpu_alloc_mutex){+.+.}, at:  
pcpu_balance_workfn+0xb7/0x1310 mm/percpu.c:1845
  #3: ffffffff89851b18 (vmap_area_lock){+.+.}, at: spin_lock  
include/linux/spinlock.h:338 [inline]
  #3: ffffffff89851b18 (vmap_area_lock){+.+.}, at:  
pcpu_get_vm_areas+0x3b27/0x3f00 mm/vmalloc.c:3431
Preemption disabled at:
[<ffffffff81a89ce7>] spin_lock include/linux/spinlock.h:338 [inline]
[<ffffffff81a89ce7>] pcpu_get_vm_areas+0x3b27/0x3f00 mm/vmalloc.c:3431
CPU: 0 PID: 9071 Comm: kworker/0:3 Not tainted  
5.4.0-next-20191129-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Workqueue: events pcpu_balance_workfn
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0x197/0x210 lib/dump_stack.c:118
  ___might_sleep.cold+0x1fb/0x23e kernel/sched/core.c:6800
  __might_sleep+0x95/0x190 kernel/sched/core.c:6753
  prepare_alloc_pages mm/page_alloc.c:4681 [inline]
  __alloc_pages_nodemask+0x523/0x910 mm/page_alloc.c:4730
  alloc_pages_current+0x107/0x210 mm/mempolicy.c:2211
  alloc_pages include/linux/gfp.h:532 [inline]
  __get_free_pages+0xc/0x40 mm/page_alloc.c:4786
  kasan_populate_vmalloc_pte mm/kasan/common.c:762 [inline]
  kasan_populate_vmalloc_pte+0x2f/0x1c0 mm/kasan/common.c:753
  apply_to_pte_range mm/memory.c:2041 [inline]
  apply_to_pmd_range mm/memory.c:2068 [inline]
  apply_to_pud_range mm/memory.c:2088 [inline]
  apply_to_p4d_range mm/memory.c:2108 [inline]
  apply_to_page_range+0x445/0x700 mm/memory.c:2133
  kasan_populate_vmalloc+0x68/0x90 mm/kasan/common.c:791
  pcpu_get_vm_areas+0x3c77/0x3f00 mm/vmalloc.c:3439
  pcpu_create_chunk+0x24e/0x7f0 mm/percpu-vm.c:340
  pcpu_balance_workfn+0xf1b/0x1310 mm/percpu.c:1934
  process_one_work+0x9af/0x1740 kernel/workqueue.c:2264
  worker_thread+0x98/0xe40 kernel/workqueue.c:2410
  kthread+0x361/0x430 kernel/kthread.c:255
  ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Re: BUG: sleeping function called from invalid context in __alloc_pages_nodemask

[syzbot]

syzbot has found a reproducer for the following crash on:

HEAD commit:    419593da Add linux-next specific files for 20191129
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=177a9712e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7c04b0959e75c206
dashboard link: https://syzkaller.appspot.com/bug?extid=4925d60532bf4c399608
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=16148e9ce00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12a1f786e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+4925d60532bf4c399608@syzkaller.appspotmail.com

BUG: sleeping function called from invalid context at mm/page_alloc.c:4681
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 9065, name:  
kworker/1:3
4 locks held by kworker/1:3/9065:
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: __write_once_size  
include/linux/compiler.h:247 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: arch_atomic64_set  
arch/x86/include/asm/atomic64_64.h:34 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: atomic64_set  
include/asm-generic/atomic-instrumented.h:868 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: atomic_long_set  
include/asm-generic/atomic-long.h:40 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at: set_work_data  
kernel/workqueue.c:615 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at:  
set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline]
  #0: ffff8880aa026d28 ((wq_completion)events){+.+.}, at:  
process_one_work+0x88b/0x1740 kernel/workqueue.c:2235
  #1: ffffc90002177dc0 (pcpu_balance_work){+.+.}, at:  
process_one_work+0x8c1/0x1740 kernel/workqueue.c:2239
  #2: ffffffff8983ff20 (pcpu_alloc_mutex){+.+.}, at:  
pcpu_balance_workfn+0xb7/0x1310 mm/percpu.c:1845
  #3: ffffffff89851b18 (vmap_area_lock){+.+.}, at: spin_lock  
include/linux/spinlock.h:338 [inline]
  #3: ffffffff89851b18 (vmap_area_lock){+.+.}, at:  
pcpu_get_vm_areas+0x3b27/0x3f00 mm/vmalloc.c:3431
Preemption disabled at:
[<ffffffff81a89ce7>] spin_lock include/linux/spinlock.h:338 [inline]
[<ffffffff81a89ce7>] pcpu_get_vm_areas+0x3b27/0x3f00 mm/vmalloc.c:3431
CPU: 1 PID: 9065 Comm: kworker/1:3 Not tainted  
5.4.0-next-20191129-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Workqueue: events pcpu_balance_workfn
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0x197/0x210 lib/dump_stack.c:118
  ___might_sleep.cold+0x1fb/0x23e kernel/sched/core.c:6800
  __might_sleep+0x95/0x190 kernel/sched/core.c:6753
  prepare_alloc_pages mm/page_alloc.c:4681 [inline]
  __alloc_pages_nodemask+0x523/0x910 mm/page_alloc.c:4730
  alloc_pages_current+0x107/0x210 mm/mempolicy.c:2211
  alloc_pages include/linux/gfp.h:532 [inline]
  __get_free_pages+0xc/0x40 mm/page_alloc.c:4786
  kasan_populate_vmalloc_pte mm/kasan/common.c:762 [inline]
  kasan_populate_vmalloc_pte+0x2f/0x1c0 mm/kasan/common.c:753
  apply_to_pte_range mm/memory.c:2041 [inline]
  apply_to_pmd_range mm/memory.c:2068 [inline]
  apply_to_pud_range mm/memory.c:2088 [inline]
  apply_to_p4d_range mm/memory.c:2108 [inline]
  apply_to_page_range+0x445/0x700 mm/memory.c:2133
  kasan_populate_vmalloc+0x68/0x90 mm/kasan/common.c:791
  pcpu_get_vm_areas+0x3c77/0x3f00 mm/vmalloc.c:3439
  pcpu_create_chunk+0x24e/0x7f0 mm/percpu-vm.c:340
  pcpu_balance_workfn+0xf1b/0x1310 mm/percpu.c:1934
  process_one_work+0x9af/0x1740 kernel/workqueue.c:2264
  worker_thread+0x98/0xe40 kernel/workqueue.c:2410
  kthread+0x361/0x430 kernel/kthread.c:255
  ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Re: BUG: sleeping function called from invalid context in __alloc_pages_nodemask

[syzbot]

syzbot has bisected this bug to:

commit ab92d68fc22f9afab480153bd82a20f6e2533769
Author: Taehee Yoo <ap420073@gmail.com>
Date:   Mon Oct 21 18:47:51 2019 +0000

     net: core: add generic lockdep keys

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=15769712e00000
start commit:   419593da Add linux-next specific files for 20191129
git tree:       linux-next
final crash:    https://syzkaller.appspot.com/x/report.txt?x=17769712e00000
console output: https://syzkaller.appspot.com/x/log.txt?x=13769712e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=7c04b0959e75c206
dashboard link: https://syzkaller.appspot.com/bug?extid=4925d60532bf4c399608
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=16148e9ce00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12a1f786e00000

Reported-by: syzbot+4925d60532bf4c399608@syzkaller.appspotmail.com
Fixes: ab92d68fc22f ("net: core: add generic lockdep keys")

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