Hi all,
I experience failed assertions on an x86_64 KVM virtual machine (VirtIO devices) when accessing files on NFS 4 shares while having cachefilesd (0.10.7) running.
Good kernel: 4.14.49
Bad kernels: 5.8.14, 5.9.0
The machine is rendered unusable (100% CPU) and requires a hard-reset.
This is the console error report captured via serial console:
CacheFiles:
CacheFiles: Assertion failed
invalid opcode: 0000 [#1]
CPU: 0 PID: 4215 Comm: git Not tainted 5.9.0vzlinux #3
RIP: 0010:cachefiles_read_or_alloc_pages+0x9e/0x5cf
Code: ff 0f 0b 49 8b 46 30 48 8b 40 70 48 83 78 20 00 75 1a 48 c7 c7 20 fc e8 81 e8 cf 7a e7 ff 48 c7 c7 30 fc e8 81 e8 c3 7a e7 ff <0f> 0b 49 8b 46 28 ba 0c 00 00 00 c6 44 24 40 00 c6 44 24 41 00 c7
RSP: 0000:ffffc900015cba98 EFLAGS: 00010292
RAX: 000000000000001c RBX: ffffc900015cbc04 RCX: 0000000000000027
RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff82039340
RBP: ffff88803c3469c0 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000001e88c R11: 000000000000003c R12: ffffc900015cbd70
R13: ffff88803c3469c0 R14: ffff88802e2d2fd0 R15: ffff88802bf27000
FS: 00007feea1027fc0(0000) GS:ffffffff82030000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007feea1036000 CR3: 000000002bcbd005 CR4: 00000000001706b0
Call Trace:
? nfs_access_add_cache+0x140/0x1c5
? slab_free_freelist_hook+0x45/0xc4
? slab_pre_alloc_hook.isra.81+0x26/0x37
? fscache_run_op.isra.13+0x57/0x69
__fscache_read_or_alloc_pages+0x1a6/0x1f2
__nfs_readpages_from_fscache+0x51/0xa9
nfs_readpages+0x111/0x133
? get_page_from_freelist+0x734/0x8a1
read_pages+0x8c/0x102
? __alloc_pages_nodemask+0xd4/0x122
? page_cache_readahead_unbounded+0xce/0x17d
page_cache_readahead_unbounded+0xce/0x17d
filemap_fault+0x1f9/0x3d8
__do_fault+0x44/0x63
handle_mm_fault+0x70e/0xad3
exc_page_fault+0x1f0/0x311
? asm_exc_page_fault+0x5/0x20
asm_exc_page_fault+0x1b/0x20
RIP: 0033:0x7feea0991bef
Code: 41 c7 45 00 1d 00 00 00 e9 1e f8 ff ff 41 8b 55 08 85 d2 0f 84 72 07 00 00 83 fb 0f 0f 87 37 14 00 00 85 ed 0f 84 83 f5 ff ff <41> 0f b6 34 24 89 d9 8d 45 ff 49 8d 7c 24 01 48 d3 e6 8d 4b 08 4c
RSP: 002b:00007fffbb7d5240 EFLAGS: 00010202
RAX: 00007feea0991bd2 RBX: 0000000000000000 RCX: 00000000000000d0
RDX: 0000000000000001 RSI: 000055d7e1bf9c10 RDI: 00007fffbb7d52a0
RBP: 00000000000000d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 00007fffbb7d5390 R12: 00007feea1036000
R13: 000055d7e1bf9900 R14: 00007fffbb7d5570 R15: 0000000000000000
---[ end trace cad4b4a2dd601cdd ]---
RIP: 0010:cachefiles_read_or_alloc_pages+0x9e/0x5cf
Code: ff 0f 0b 49 8b 46 30 48 8b 40 70 48 83 78 20 00 75 1a 48 c7 c7 20 fc e8 81 e8 cf 7a e7 ff 48 c7 c7 30 fc e8 81 e8 c3 7a e7 ff <0f> 0b 49 8b 46 28 ba 0c 00 00 00 c6 44 24 40 00 c6 44 24 41 00 c7
RSP: 0000:ffffc900015cba98 EFLAGS: 00010292
RAX: 000000000000001c RBX: ffffc900015cbc04 RCX: 0000000000000027
RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff82039340
RBP: ffff88803c3469c0 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000001e88c R11: 000000000000003c R12: ffffc900015cbd70
R13: ffff88803c3469c0 R14: ffff88802e2d2fd0 R15: ffff88802bf27000
FS: 00007feea1027fc0(0000) GS:ffffffff82030000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007feea1036000 CR3: 000000002bcbd005 CR4: 00000000001706b0
Kernel panic - not syncing: Fatal exception
Kernel Offset: disabled
---[ end Kernel panic - not syncing: Fatal exception ]---
Feel free to ask for further info or testing patches.
Thank you!
Regards,
Jonas Zeiger
Ps: I found this mail https://lkml.org/lkml/2020/3/20/399 describing a similar issue, but it may be unrelated.
Seems like this is already being worked on and has also been reported as:
https://bugzilla.kernel.org/show_bug.cgi?id=208883
On 2020-10-14 15:07, Jonas Zeiger wrote:
> Hi all,
>
> I experience failed assertions on an x86_64 KVM virtual machine (VirtIO devices) when accessing files on NFS 4 shares while having cachefilesd (0.10.7) running.
>
> Good kernel: 4.14.49
> Bad kernels: 5.8.14, 5.9.0
>
> The machine is rendered unusable (100% CPU) and requires a hard-reset.
>
> This is the console error report captured via serial console:
>
> CacheFiles:
> CacheFiles: Assertion failed
> invalid opcode: 0000 [#1]
> CPU: 0 PID: 4215 Comm: git Not tainted 5.9.0vzlinux #3
> RIP: 0010:cachefiles_read_or_alloc_pages+0x9e/0x5cf
> Code: ff 0f 0b 49 8b 46 30 48 8b 40 70 48 83 78 20 00 75 1a 48 c7 c7 20 fc e8 81 e8 cf 7a e7 ff 48 c7 c7 30 fc e8 81 e8 c3 7a e7 ff <0f> 0b 49 8b 46 28 ba 0c 00 00 00 c6 44 24 40 00 c6 44 24 41 00 c7
> RSP: 0000:ffffc900015cba98 EFLAGS: 00010292
> RAX: 000000000000001c RBX: ffffc900015cbc04 RCX: 0000000000000027
> RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff82039340
> RBP: ffff88803c3469c0 R08: 0000000000000000 R09: 0000000000000000
> R10: 000000000001e88c R11: 000000000000003c R12: ffffc900015cbd70
> R13: ffff88803c3469c0 R14: ffff88802e2d2fd0 R15: ffff88802bf27000
> FS: 00007feea1027fc0(0000) GS:ffffffff82030000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007feea1036000 CR3: 000000002bcbd005 CR4: 00000000001706b0
> Call Trace:
> ? nfs_access_add_cache+0x140/0x1c5
> ? slab_free_freelist_hook+0x45/0xc4
> ? slab_pre_alloc_hook.isra.81+0x26/0x37
> ? fscache_run_op.isra.13+0x57/0x69
> __fscache_read_or_alloc_pages+0x1a6/0x1f2
> __nfs_readpages_from_fscache+0x51/0xa9
> nfs_readpages+0x111/0x133
> ? get_page_from_freelist+0x734/0x8a1
> read_pages+0x8c/0x102
> ? __alloc_pages_nodemask+0xd4/0x122
> ? page_cache_readahead_unbounded+0xce/0x17d
> page_cache_readahead_unbounded+0xce/0x17d
> filemap_fault+0x1f9/0x3d8
> __do_fault+0x44/0x63
> handle_mm_fault+0x70e/0xad3
> exc_page_fault+0x1f0/0x311
> ? asm_exc_page_fault+0x5/0x20
> asm_exc_page_fault+0x1b/0x20
> RIP: 0033:0x7feea0991bef
> Code: 41 c7 45 00 1d 00 00 00 e9 1e f8 ff ff 41 8b 55 08 85 d2 0f 84 72 07 00 00 83 fb 0f 0f 87 37 14 00 00 85 ed 0f 84 83 f5 ff ff <41> 0f b6 34 24 89 d9 8d 45 ff 49 8d 7c 24 01 48 d3 e6 8d 4b 08 4c
> RSP: 002b:00007fffbb7d5240 EFLAGS: 00010202
> RAX: 00007feea0991bd2 RBX: 0000000000000000 RCX: 00000000000000d0
> RDX: 0000000000000001 RSI: 000055d7e1bf9c10 RDI: 00007fffbb7d52a0
> RBP: 00000000000000d0 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 00007fffbb7d5390 R12: 00007feea1036000
> R13: 000055d7e1bf9900 R14: 00007fffbb7d5570 R15: 0000000000000000
> ---[ end trace cad4b4a2dd601cdd ]---
> RIP: 0010:cachefiles_read_or_alloc_pages+0x9e/0x5cf
> Code: ff 0f 0b 49 8b 46 30 48 8b 40 70 48 83 78 20 00 75 1a 48 c7 c7 20 fc e8 81 e8 cf 7a e7 ff 48 c7 c7 30 fc e8 81 e8 c3 7a e7 ff <0f> 0b 49 8b 46 28 ba 0c 00 00 00 c6 44 24 40 00 c6 44 24 41 00 c7
> RSP: 0000:ffffc900015cba98 EFLAGS: 00010292
> RAX: 000000000000001c RBX: ffffc900015cbc04 RCX: 0000000000000027
> RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff82039340
> RBP: ffff88803c3469c0 R08: 0000000000000000 R09: 0000000000000000
> R10: 000000000001e88c R11: 000000000000003c R12: ffffc900015cbd70
> R13: ffff88803c3469c0 R14: ffff88802e2d2fd0 R15: ffff88802bf27000
> FS: 00007feea1027fc0(0000) GS:ffffffff82030000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007feea1036000 CR3: 000000002bcbd005 CR4: 00000000001706b0
> Kernel panic - not syncing: Fatal exception
> Kernel Offset: disabled
> ---[ end Kernel panic - not syncing: Fatal exception ]---
>
> Feel free to ask for further info or testing patches.
>
> Thank you!
>
> Regards,
> Jonas Zeiger
>
>
> Ps: I found this mail https://lkml.org/lkml/2020/3/20/399 describing a similar issue, but it may be unrelated.
On Wed, Oct 14, 2020 at 9:13 AM Jonas Zeiger <[email protected]> wrote:
>
> Hi all,
>
> I experience failed assertions on an x86_64 KVM virtual machine (VirtIO devices) when accessing files on NFS 4 shares while having cachefilesd (0.10.7) running.
>
> Good kernel: 4.14.49
> Bad kernels: 5.8.14, 5.9.0
>
> The machine is rendered unusable (100% CPU) and requires a hard-reset.
>
> This is the console error report captured via serial console:
>
> CacheFiles:
> CacheFiles: Assertion failed
> invalid opcode: 0000 [#1]
> CPU: 0 PID: 4215 Comm: git Not tainted 5.9.0vzlinux #3
> RIP: 0010:cachefiles_read_or_alloc_pages+0x9e/0x5cf
> Code: ff 0f 0b 49 8b 46 30 48 8b 40 70 48 83 78 20 00 75 1a 48 c7 c7 20 fc e8 81 e8 cf 7a e7 ff 48 c7 c7 30 fc e8 81 e8 c3 7a e7 ff <0f> 0b 49 8b 46 28 ba 0c 00 00 00 c6 44 24 40 00 c6 44 24 41 00 c7
Can you do
eu-addr2line -e ./vmlinux cachefiles_read_or_alloc_pages+0x9e
That should give the line # of the assertion.
> RSP: 0000:ffffc900015cba98 EFLAGS: 00010292
> RAX: 000000000000001c RBX: ffffc900015cbc04 RCX: 0000000000000027
> RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff82039340
> RBP: ffff88803c3469c0 R08: 0000000000000000 R09: 0000000000000000
> R10: 000000000001e88c R11: 000000000000003c R12: ffffc900015cbd70
> R13: ffff88803c3469c0 R14: ffff88802e2d2fd0 R15: ffff88802bf27000
> FS: 00007feea1027fc0(0000) GS:ffffffff82030000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007feea1036000 CR3: 000000002bcbd005 CR4: 00000000001706b0
> Call Trace:
> ? nfs_access_add_cache+0x140/0x1c5
> ? slab_free_freelist_hook+0x45/0xc4
> ? slab_pre_alloc_hook.isra.81+0x26/0x37
> ? fscache_run_op.isra.13+0x57/0x69
> __fscache_read_or_alloc_pages+0x1a6/0x1f2
> __nfs_readpages_from_fscache+0x51/0xa9
> nfs_readpages+0x111/0x133
> ? get_page_from_freelist+0x734/0x8a1
> read_pages+0x8c/0x102
> ? __alloc_pages_nodemask+0xd4/0x122
> ? page_cache_readahead_unbounded+0xce/0x17d
> page_cache_readahead_unbounded+0xce/0x17d
> filemap_fault+0x1f9/0x3d8
> __do_fault+0x44/0x63
> handle_mm_fault+0x70e/0xad3
> exc_page_fault+0x1f0/0x311
> ? asm_exc_page_fault+0x5/0x20
> asm_exc_page_fault+0x1b/0x20
> RIP: 0033:0x7feea0991bef
> Code: 41 c7 45 00 1d 00 00 00 e9 1e f8 ff ff 41 8b 55 08 85 d2 0f 84 72 07 00 00 83 fb 0f 0f 87 37 14 00 00 85 ed 0f 84 83 f5 ff ff <41> 0f b6 34 24 89 d9 8d 45 ff 49 8d 7c 24 01 48 d3 e6 8d 4b 08 4c
> RSP: 002b:00007fffbb7d5240 EFLAGS: 00010202
> RAX: 00007feea0991bd2 RBX: 0000000000000000 RCX: 00000000000000d0
> RDX: 0000000000000001 RSI: 000055d7e1bf9c10 RDI: 00007fffbb7d52a0
> RBP: 00000000000000d0 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 00007fffbb7d5390 R12: 00007feea1036000
> R13: 000055d7e1bf9900 R14: 00007fffbb7d5570 R15: 0000000000000000
> ---[ end trace cad4b4a2dd601cdd ]---
> RIP: 0010:cachefiles_read_or_alloc_pages+0x9e/0x5cf
> Code: ff 0f 0b 49 8b 46 30 48 8b 40 70 48 83 78 20 00 75 1a 48 c7 c7 20 fc e8 81 e8 cf 7a e7 ff 48 c7 c7 30 fc e8 81 e8 c3 7a e7 ff <0f> 0b 49 8b 46 28 ba 0c 00 00 00 c6 44 24 40 00 c6 44 24 41 00 c7
> RSP: 0000:ffffc900015cba98 EFLAGS: 00010292
> RAX: 000000000000001c RBX: ffffc900015cbc04 RCX: 0000000000000027
> RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff82039340
> RBP: ffff88803c3469c0 R08: 0000000000000000 R09: 0000000000000000
> R10: 000000000001e88c R11: 000000000000003c R12: ffffc900015cbd70
> R13: ffff88803c3469c0 R14: ffff88802e2d2fd0 R15: ffff88802bf27000
> FS: 00007feea1027fc0(0000) GS:ffffffff82030000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007feea1036000 CR3: 000000002bcbd005 CR4: 00000000001706b0
> Kernel panic - not syncing: Fatal exception
> Kernel Offset: disabled
> ---[ end Kernel panic - not syncing: Fatal exception ]---
>
> Feel free to ask for further info or testing patches.
>
> Thank you!
>
> Regards,
> Jonas Zeiger
>
>
> Ps: I found this mail https://lkml.org/lkml/2020/3/20/399 describing a similar issue, but it may be unrelated.
>
Hi David,
root@host:/usr/src/linux-5.9# eu-addr2line -e ./vmlinux cachefiles_read_or_alloc_pages+0x9e
fs/cachefiles/rdwr.c:715
Thank you for looking into it!
-Jonas
On 2020-10-14 18:43, David Wysochanski wrote:
> On Wed, Oct 14, 2020 at 9:13 AM Jonas Zeiger <[email protected]> wrote:
>>
>> Hi all,
>>
>> I experience failed assertions on an x86_64 KVM virtual machine (VirtIO devices) when accessing files on NFS 4 shares while having cachefilesd (0.10.7) running.
>>
>> Good kernel: 4.14.49
>> Bad kernels: 5.8.14, 5.9.0
>>
>> The machine is rendered unusable (100% CPU) and requires a hard-reset.
>>
>> This is the console error report captured via serial console:
>>
>> CacheFiles:
>> CacheFiles: Assertion failed
>> invalid opcode: 0000 [#1]
>> CPU: 0 PID: 4215 Comm: git Not tainted 5.9.0vzlinux #3
>> RIP: 0010:cachefiles_read_or_alloc_pages+0x9e/0x5cf
>> Code: ff 0f 0b 49 8b 46 30 48 8b 40 70 48 83 78 20 00 75 1a 48 c7 c7 20 fc e8 81 e8 cf 7a e7 ff 48 c7 c7 30 fc e8 81 e8 c3 7a e7 ff <0f> 0b 49 8b 46 28 ba 0c 00 00 00 c6 44 24 40 00 c6 44 24 41 00 c7
>
>
> Can you do
>
> eu-addr2line -e ./vmlinux cachefiles_read_or_alloc_pages+0x9e
>
> That should give the line # of the assertion.
>
>
>> RSP: 0000:ffffc900015cba98 EFLAGS: 00010292
>> RAX: 000000000000001c RBX: ffffc900015cbc04 RCX: 0000000000000027
>> RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff82039340
>> RBP: ffff88803c3469c0 R08: 0000000000000000 R09: 0000000000000000
>> R10: 000000000001e88c R11: 000000000000003c R12: ffffc900015cbd70
>> R13: ffff88803c3469c0 R14: ffff88802e2d2fd0 R15: ffff88802bf27000
>> FS: 00007feea1027fc0(0000) GS:ffffffff82030000(0000) knlGS:0000000000000000
>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>> CR2: 00007feea1036000 CR3: 000000002bcbd005 CR4: 00000000001706b0
>> Call Trace:
>> ? nfs_access_add_cache+0x140/0x1c5
>> ? slab_free_freelist_hook+0x45/0xc4
>> ? slab_pre_alloc_hook.isra.81+0x26/0x37
>> ? fscache_run_op.isra.13+0x57/0x69
>> __fscache_read_or_alloc_pages+0x1a6/0x1f2
>> __nfs_readpages_from_fscache+0x51/0xa9
>> nfs_readpages+0x111/0x133
>> ? get_page_from_freelist+0x734/0x8a1
>> read_pages+0x8c/0x102
>> ? __alloc_pages_nodemask+0xd4/0x122
>> ? page_cache_readahead_unbounded+0xce/0x17d
>> page_cache_readahead_unbounded+0xce/0x17d
>> filemap_fault+0x1f9/0x3d8
>> __do_fault+0x44/0x63
>> handle_mm_fault+0x70e/0xad3
>> exc_page_fault+0x1f0/0x311
>> ? asm_exc_page_fault+0x5/0x20
>> asm_exc_page_fault+0x1b/0x20
>> RIP: 0033:0x7feea0991bef
>> Code: 41 c7 45 00 1d 00 00 00 e9 1e f8 ff ff 41 8b 55 08 85 d2 0f 84 72 07 00 00 83 fb 0f 0f 87 37 14 00 00 85 ed 0f 84 83 f5 ff ff <41> 0f b6 34 24 89 d9 8d 45 ff 49 8d 7c 24 01 48 d3 e6 8d 4b 08 4c
>> RSP: 002b:00007fffbb7d5240 EFLAGS: 00010202
>> RAX: 00007feea0991bd2 RBX: 0000000000000000 RCX: 00000000000000d0
>> RDX: 0000000000000001 RSI: 000055d7e1bf9c10 RDI: 00007fffbb7d52a0
>> RBP: 00000000000000d0 R08: 0000000000000000 R09: 0000000000000000
>> R10: 0000000000000000 R11: 00007fffbb7d5390 R12: 00007feea1036000
>> R13: 000055d7e1bf9900 R14: 00007fffbb7d5570 R15: 0000000000000000
>> ---[ end trace cad4b4a2dd601cdd ]---
>> RIP: 0010:cachefiles_read_or_alloc_pages+0x9e/0x5cf
>> Code: ff 0f 0b 49 8b 46 30 48 8b 40 70 48 83 78 20 00 75 1a 48 c7 c7 20 fc e8 81 e8 cf 7a e7 ff 48 c7 c7 30 fc e8 81 e8 c3 7a e7 ff <0f> 0b 49 8b 46 28 ba 0c 00 00 00 c6 44 24 40 00 c6 44 24 41 00 c7
>> RSP: 0000:ffffc900015cba98 EFLAGS: 00010292
>> RAX: 000000000000001c RBX: ffffc900015cbc04 RCX: 0000000000000027
>> RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff82039340
>> RBP: ffff88803c3469c0 R08: 0000000000000000 R09: 0000000000000000
>> R10: 000000000001e88c R11: 000000000000003c R12: ffffc900015cbd70
>> R13: ffff88803c3469c0 R14: ffff88802e2d2fd0 R15: ffff88802bf27000
>> FS: 00007feea1027fc0(0000) GS:ffffffff82030000(0000) knlGS:0000000000000000
>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>> CR2: 00007feea1036000 CR3: 000000002bcbd005 CR4: 00000000001706b0
>> Kernel panic - not syncing: Fatal exception
>> Kernel Offset: disabled
>> ---[ end Kernel panic - not syncing: Fatal exception ]---
>>
>> Feel free to ask for further info or testing patches.
>>
>> Thank you!
>>
>> Regards,
>> Jonas Zeiger
>>
>>
>> Ps: I found this mail https://lkml.org/lkml/2020/3/20/399 describing a similar issue, but it may be unrelated.
>>
Yep that matches the known issue. If you apply Takashi's patch here
and rebuild, you should be good:
https://bugzilla.kernel.org/show_bug.cgi?id=208883#c5
On Wed, Oct 14, 2020 at 5:13 PM Jonas Zeiger <[email protected]> wrote:
>
> Hi David,
>
> root@host:/usr/src/linux-5.9# eu-addr2line -e ./vmlinux cachefiles_read_or_alloc_pages+0x9e
> fs/cachefiles/rdwr.c:715
>
> Thank you for looking into it!
>
> -Jonas
>
> On 2020-10-14 18:43, David Wysochanski wrote:
> > On Wed, Oct 14, 2020 at 9:13 AM Jonas Zeiger <[email protected]> wrote:
> >>
> >> Hi all,
> >>
> >> I experience failed assertions on an x86_64 KVM virtual machine (VirtIO devices) when accessing files on NFS 4 shares while having cachefilesd (0.10.7) running.
> >>
> >> Good kernel: 4.14.49
> >> Bad kernels: 5.8.14, 5.9.0
> >>
> >> The machine is rendered unusable (100% CPU) and requires a hard-reset.
> >>
> >> This is the console error report captured via serial console:
> >>
> >> CacheFiles:
> >> CacheFiles: Assertion failed
> >> invalid opcode: 0000 [#1]
> >> CPU: 0 PID: 4215 Comm: git Not tainted 5.9.0vzlinux #3
> >> RIP: 0010:cachefiles_read_or_alloc_pages+0x9e/0x5cf
> >> Code: ff 0f 0b 49 8b 46 30 48 8b 40 70 48 83 78 20 00 75 1a 48 c7 c7 20 fc e8 81 e8 cf 7a e7 ff 48 c7 c7 30 fc e8 81 e8 c3 7a e7 ff <0f> 0b 49 8b 46 28 ba 0c 00 00 00 c6 44 24 40 00 c6 44 24 41 00 c7
> >
> >
> > Can you do
> >
> > eu-addr2line -e ./vmlinux cachefiles_read_or_alloc_pages+0x9e
> >
> > That should give the line # of the assertion.
> >
> >
> >> RSP: 0000:ffffc900015cba98 EFLAGS: 00010292
> >> RAX: 000000000000001c RBX: ffffc900015cbc04 RCX: 0000000000000027
> >> RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff82039340
> >> RBP: ffff88803c3469c0 R08: 0000000000000000 R09: 0000000000000000
> >> R10: 000000000001e88c R11: 000000000000003c R12: ffffc900015cbd70
> >> R13: ffff88803c3469c0 R14: ffff88802e2d2fd0 R15: ffff88802bf27000
> >> FS: 00007feea1027fc0(0000) GS:ffffffff82030000(0000) knlGS:0000000000000000
> >> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> >> CR2: 00007feea1036000 CR3: 000000002bcbd005 CR4: 00000000001706b0
> >> Call Trace:
> >> ? nfs_access_add_cache+0x140/0x1c5
> >> ? slab_free_freelist_hook+0x45/0xc4
> >> ? slab_pre_alloc_hook.isra.81+0x26/0x37
> >> ? fscache_run_op.isra.13+0x57/0x69
> >> __fscache_read_or_alloc_pages+0x1a6/0x1f2
> >> __nfs_readpages_from_fscache+0x51/0xa9
> >> nfs_readpages+0x111/0x133
> >> ? get_page_from_freelist+0x734/0x8a1
> >> read_pages+0x8c/0x102
> >> ? __alloc_pages_nodemask+0xd4/0x122
> >> ? page_cache_readahead_unbounded+0xce/0x17d
> >> page_cache_readahead_unbounded+0xce/0x17d
> >> filemap_fault+0x1f9/0x3d8
> >> __do_fault+0x44/0x63
> >> handle_mm_fault+0x70e/0xad3
> >> exc_page_fault+0x1f0/0x311
> >> ? asm_exc_page_fault+0x5/0x20
> >> asm_exc_page_fault+0x1b/0x20
> >> RIP: 0033:0x7feea0991bef
> >> Code: 41 c7 45 00 1d 00 00 00 e9 1e f8 ff ff 41 8b 55 08 85 d2 0f 84 72 07 00 00 83 fb 0f 0f 87 37 14 00 00 85 ed 0f 84 83 f5 ff ff <41> 0f b6 34 24 89 d9 8d 45 ff 49 8d 7c 24 01 48 d3 e6 8d 4b 08 4c
> >> RSP: 002b:00007fffbb7d5240 EFLAGS: 00010202
> >> RAX: 00007feea0991bd2 RBX: 0000000000000000 RCX: 00000000000000d0
> >> RDX: 0000000000000001 RSI: 000055d7e1bf9c10 RDI: 00007fffbb7d52a0
> >> RBP: 00000000000000d0 R08: 0000000000000000 R09: 0000000000000000
> >> R10: 0000000000000000 R11: 00007fffbb7d5390 R12: 00007feea1036000
> >> R13: 000055d7e1bf9900 R14: 00007fffbb7d5570 R15: 0000000000000000
> >> ---[ end trace cad4b4a2dd601cdd ]---
> >> RIP: 0010:cachefiles_read_or_alloc_pages+0x9e/0x5cf
> >> Code: ff 0f 0b 49 8b 46 30 48 8b 40 70 48 83 78 20 00 75 1a 48 c7 c7 20 fc e8 81 e8 cf 7a e7 ff 48 c7 c7 30 fc e8 81 e8 c3 7a e7 ff <0f> 0b 49 8b 46 28 ba 0c 00 00 00 c6 44 24 40 00 c6 44 24 41 00 c7
> >> RSP: 0000:ffffc900015cba98 EFLAGS: 00010292
> >> RAX: 000000000000001c RBX: ffffc900015cbc04 RCX: 0000000000000027
> >> RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffffffff82039340
> >> RBP: ffff88803c3469c0 R08: 0000000000000000 R09: 0000000000000000
> >> R10: 000000000001e88c R11: 000000000000003c R12: ffffc900015cbd70
> >> R13: ffff88803c3469c0 R14: ffff88802e2d2fd0 R15: ffff88802bf27000
> >> FS: 00007feea1027fc0(0000) GS:ffffffff82030000(0000) knlGS:0000000000000000
> >> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> >> CR2: 00007feea1036000 CR3: 000000002bcbd005 CR4: 00000000001706b0
> >> Kernel panic - not syncing: Fatal exception
> >> Kernel Offset: disabled
> >> ---[ end Kernel panic - not syncing: Fatal exception ]---
> >>
> >> Feel free to ask for further info or testing patches.
> >>
> >> Thank you!
> >>
> >> Regards,
> >> Jonas Zeiger
> >>
> >>
> >> Ps: I found this mail https://lkml.org/lkml/2020/3/20/399 describing a similar issue, but it may be unrelated.
> >>
>