* Vlastimil Babka:
> On 9/30/19 11:17 PM, Dave Chinner wrote:
>> On Mon, Sep 30, 2019 at 09:07:53PM +0200, Florian Weimer wrote:
>>> * Dave Chinner:
>>>
>>>> On Mon, Sep 30, 2019 at 09:28:27AM +0200, Florian Weimer wrote:
>>>>> Simply running “du -hc” on a large directory tree causes du to be
>>>>> killed because of kernel paging request failure in the XFS code.
>>>>
>>>> dmesg output? if the system was still running, then you might be
>>>> able to pull the trace from syslog. But we can't do much without
>>>> knowing what the actual failure was....
>>>
>>> Huh. I actually have something in syslog:
>>>
>>> [ 4001.238411] BUG: kernel NULL pointer dereference, address:
>>> 0000000000000000
>>> [ 4001.238415] #PF: supervisor read access in kernel mode
>>> [ 4001.238417] #PF: error_code(0x0000) - not-present page
>>> [ 4001.238418] PGD 0 P4D 0
>>> [ 4001.238420] Oops: 0000 [#1] SMP PTI
>>> [ 4001.238423] CPU: 3 PID: 143 Comm: kswapd0 Tainted: G I 5.2.16fw+
>>> #1
>>> [ 4001.238424] Hardware name: System manufacturer System Product
>>> Name/P6X58D-E, BIOS 0701 05/10/2011
>>> [ 4001.238430] RIP: 0010:__reset_isolation_pfn+0x27f/0x3c0
>>
>> That's memory compaction code it's crashed in.
>>
>>> [ 4001.238432] Code: 44 c6 48 8b 00 a8 10 74 bc 49 8b 16 48 89 d0
>>> 48 c1 ea 35 48 8b 14 d7 48 c1 e8 2d 48 85 d2 74 0a 0f b6 c0 48 c1
>>> e0 04 48 01 c2 <48> 8b 02 4c 89 f2 41 b8 01 00 00 00 31 f6 b9 03 00
>>> 00 00 4c 89 f7
>
> Tried to decode it, but couldn't match it to source code, my version of
> compiled code is too different. Would it be possible to either send
> mm/compaction.o from the matching build, or output of 'objdump -d -l'
> for the __reset_isolation_pfn function?
See below. I don't have debuginfo for this build, and the binary does
not reproduce for some reason. Due to the heavy inlining, it might be
quite hard to figure out what's going on.
I've switched to kernel builds with debuginfo from now on. I'm
surprised that it's not the default.
0000000000000120 <__reset_isolation_pfn>:
__reset_isolation_pfn():
120: 48 89 f0 mov %rsi,%rax
123: 48 c1 e8 0f shr $0xf,%rax
127: 48 3d ff ff 07 00 cmp $0x7ffff,%rax
12d: 0f 87 83 00 00 00 ja 1b6 <__reset_isolation_pfn+0x96>
133: 4c 8b 0d 00 00 00 00 mov 0x0(%rip),%r9 # 13a <__reset_isolation_pfn+0x1a>
136: R_X86_64_PC32 mem_section-0x4
13a: 4d 85 c9 test %r9,%r9
13d: 74 77 je 1b6 <__reset_isolation_pfn+0x96>
13f: 49 89 f2 mov %rsi,%r10
142: 49 c1 ea 17 shr $0x17,%r10
146: 4f 8b 0c d1 mov (%r9,%r10,8),%r9
14a: 4d 85 c9 test %r9,%r9
14d: 74 67 je 1b6 <__reset_isolation_pfn+0x96>
14f: 0f b6 c0 movzbl %al,%eax
152: 48 c1 e0 04 shl $0x4,%rax
156: 4c 01 c8 add %r9,%rax
159: 74 5b je 1b6 <__reset_isolation_pfn+0x96>
15b: 4c 8b 08 mov (%rax),%r9
15e: 41 f6 c1 02 test $0x2,%r9b
162: 74 52 je 1b6 <__reset_isolation_pfn+0x96>
164: 48 6b c6 38 imul $0x38,%rsi,%rax
168: 55 push %rbp
169: 49 83 e1 f8 and $0xfffffffffffffff8,%r9
16d: 48 89 e5 mov %rsp,%rbp
170: 41 57 push %r15
172: 41 56 push %r14
174: 4d 89 ce mov %r9,%r14
177: 41 55 push %r13
179: 41 54 push %r12
17b: 53 push %rbx
17c: 48 83 ec 10 sub $0x10,%rsp
180: 49 01 c6 add %rax,%r14
183: 74 1c je 1a1 <__reset_isolation_pfn+0x81>
185: 49 8b 06 mov (%r14),%rax
188: 48 c1 e8 2b shr $0x2b,%rax
18c: 83 e0 03 and $0x3,%eax
18f: 48 69 c0 80 05 00 00 imul $0x580,%rax,%rax
196: 48 05 00 00 00 00 add $0x0,%rax
198: R_X86_64_32S contig_page_data
19c: 48 39 c7 cmp %rax,%rdi
19f: 74 1c je 1bd <__reset_isolation_pfn+0x9d>
1a1: 45 31 d2 xor %r10d,%r10d
1a4: 48 83 c4 10 add $0x10,%rsp
1a8: 44 89 d0 mov %r10d,%eax
1ab: 5b pop %rbx
1ac: 41 5c pop %r12
1ae: 41 5d pop %r13
1b0: 41 5e pop %r14
1b2: 41 5f pop %r15
1b4: 5d pop %rbp
1b5: c3 retq
1b6: 45 31 d2 xor %r10d,%r10d
1b9: 44 89 d0 mov %r10d,%eax
1bc: c3 retq
1bd: 48 89 7d d0 mov %rdi,-0x30(%rbp)
1c1: 41 89 cc mov %ecx,%r12d
1c4: 41 89 cd mov %ecx,%r13d
1c7: 4c 89 f7 mov %r14,%rdi
1ca: 89 d1 mov %edx,%ecx
1cc: 41 89 d7 mov %edx,%r15d
1cf: 48 89 f3 mov %rsi,%rbx
1d2: 89 4d cc mov %ecx,-0x34(%rbp)
1d5: e8 46 fe ff ff callq 20 <pageblock_skip_persistent>
1da: 84 c0 test %al,%al
1dc: 75 c3 jne 1a1 <__reset_isolation_pfn+0x81>
1de: 45 89 fa mov %r15d,%r10d
1e1: 45 20 e2 and %r12b,%r10b
1e4: 0f 85 f3 01 00 00 jne 3dd <__reset_isolation_pfn+0x2bd>
1ea: 80 7d cc 01 cmpb $0x1,-0x34(%rbp)
1ee: 74 6d je 25d <__reset_isolation_pfn+0x13d>
1f0: 45 84 e4 test %r12b,%r12b
1f3: 74 68 je 25d <__reset_isolation_pfn+0x13d>
1f5: 49 8b 0e mov (%r14),%rcx
1f8: 48 8b 05 00 00 00 00 mov 0x0(%rip),%rax # 1ff <__reset_isolation_pfn+0xdf>
1fb: R_X86_64_PC32 mem_section-0x4
1ff: 48 89 ca mov %rcx,%rdx
202: 48 c1 ea 2d shr $0x2d,%rdx
206: 48 85 c0 test %rax,%rax
209: 74 17 je 222 <__reset_isolation_pfn+0x102>
20b: 48 c1 e9 35 shr $0x35,%rcx
20f: 48 8b 04 c8 mov (%rax,%rcx,8),%rax
213: 48 85 c0 test %rax,%rax
216: 74 0a je 222 <__reset_isolation_pfn+0x102>
218: 0f b6 d2 movzbl %dl,%edx
21b: 48 c1 e2 04 shl $0x4,%rdx
21f: 48 01 d0 add %rdx,%rax
222: 48 8b 00 mov (%rax),%rax
225: 4c 89 f6 mov %r14,%rsi
228: b9 07 00 00 00 mov $0x7,%ecx
22d: ba 02 00 00 00 mov $0x2,%edx
232: 4c 89 f7 mov %r14,%rdi
235: 48 83 e0 f8 and $0xfffffffffffffff8,%rax
239: 48 29 c6 sub %rax,%rsi
23c: 48 b8 b7 6d db b6 6d movabs $0x6db6db6db6db6db7,%rax
243: db b6 6d
246: 48 c1 fe 03 sar $0x3,%rsi
24a: 48 0f af f0 imul %rax,%rsi
24e: e8 00 00 00 00 callq 253 <__reset_isolation_pfn+0x133>
24f: R_X86_64_PLT32 get_pfnblock_flags_mask-0x4
253: 48 83 f8 01 cmp $0x1,%rax
257: 0f 85 44 ff ff ff jne 1a1 <__reset_isolation_pfn+0x81>
25d: 48 8b 7d d0 mov -0x30(%rbp),%rdi
261: 48 81 e3 00 fe ff ff and $0xfffffffffffffe00,%rbx
268: 48 8b 47 58 mov 0x58(%rdi),%rax
26c: 48 39 c3 cmp %rax,%rbx
26f: 48 89 c1 mov %rax,%rcx
272: 48 0f 43 cb cmovae %rbx,%rcx
276: 48 03 47 68 add 0x68(%rdi),%rax
27a: 48 81 c3 00 02 00 00 add $0x200,%rbx
281: 48 89 ca mov %rcx,%rdx
284: 48 c1 ea 0f shr $0xf,%rdx
288: 48 83 e8 01 sub $0x1,%rax
28c: 48 39 d8 cmp %rbx,%rax
28f: 48 0f 47 c3 cmova %rbx,%rax
293: 48 89 c6 mov %rax,%rsi
296: 48 c1 ee 0f shr $0xf,%rsi
29a: 48 81 fa ff ff 07 00 cmp $0x7ffff,%rdx
2a1: 0f 87 ab 01 00 00 ja 452 <__reset_isolation_pfn+0x332>
2a7: 48 8b 3d 00 00 00 00 mov 0x0(%rip),%rdi # 2ae <__reset_isolation_pfn+0x18e>
2aa: R_X86_64_PC32 mem_section-0x4
2ae: 48 85 ff test %rdi,%rdi
2b1: 0f 84 ea fe ff ff je 1a1 <__reset_isolation_pfn+0x81>
2b7: 49 89 ca mov %rcx,%r10
2ba: 49 c1 ea 17 shr $0x17,%r10
2be: 4e 8b 14 d7 mov (%rdi,%r10,8),%r10
2c2: 4d 85 d2 test %r10,%r10
2c5: 74 23 je 2ea <__reset_isolation_pfn+0x1ca>
2c7: 0f b6 d2 movzbl %dl,%edx
2ca: 48 c1 e2 04 shl $0x4,%rdx
2ce: 4c 01 d2 add %r10,%rdx
2d1: 74 17 je 2ea <__reset_isolation_pfn+0x1ca>
2d3: 48 8b 12 mov (%rdx),%rdx
2d6: f6 c2 02 test $0x2,%dl
2d9: 74 0f je 2ea <__reset_isolation_pfn+0x1ca>
2db: 48 6b c9 38 imul $0x38,%rcx,%rcx
2df: 48 83 e2 f8 and $0xfffffffffffffff8,%rdx
2e3: 48 01 ca add %rcx,%rdx
2e6: 4c 0f 45 f2 cmovne %rdx,%r14
2ea: 48 81 fe 00 00 08 00 cmp $0x80000,%rsi
2f1: 0f 84 aa fe ff ff je 1a1 <__reset_isolation_pfn+0x81>
2f7: 48 89 c2 mov %rax,%rdx
2fa: 48 c1 ea 17 shr $0x17,%rdx
2fe: 48 8b 14 d7 mov (%rdi,%rdx,8),%rdx
302: 48 85 d2 test %rdx,%rdx
305: 0f 84 96 fe ff ff je 1a1 <__reset_isolation_pfn+0x81>
30b: 40 0f b6 f6 movzbl %sil,%esi
30f: 48 c1 e6 04 shl $0x4,%rsi
313: 48 01 f2 add %rsi,%rdx
316: 0f 84 85 fe ff ff je 1a1 <__reset_isolation_pfn+0x81>
31c: 48 8b 12 mov (%rdx),%rdx
31f: f6 c2 02 test $0x2,%dl
322: 0f 84 79 fe ff ff je 1a1 <__reset_isolation_pfn+0x81>
328: 48 6b c0 38 imul $0x38,%rax,%rax
32c: 48 83 e2 f8 and $0xfffffffffffffff8,%rdx
330: 48 01 c2 add %rax,%rdx
333: 75 2e jne 363 <__reset_isolation_pfn+0x243>
335: e9 67 fe ff ff jmpq 1a1 <__reset_isolation_pfn+0x81>
33a: 45 84 e4 test %r12b,%r12b
33d: 74 14 je 353 <__reset_isolation_pfn+0x233>
33f: 41 8b 46 30 mov 0x30(%r14),%eax
343: 25 80 00 00 f0 and $0xf0000080,%eax
348: 3d 00 00 00 f0 cmp $0xf0000000,%eax
34d: 0f 84 21 01 00 00 je 474 <__reset_isolation_pfn+0x354>
353: 49 81 c6 c0 01 00 00 add $0x1c0,%r14
35a: 4c 39 f2 cmp %r14,%rdx
35d: 0f 86 3e fe ff ff jbe 1a1 <__reset_isolation_pfn+0x81>
363: 45 84 ff test %r15b,%r15b
366: 74 d2 je 33a <__reset_isolation_pfn+0x21a>
368: 49 8b 4e 08 mov 0x8(%r14),%rcx
36c: 48 8d 41 ff lea -0x1(%rcx),%rax
370: 83 e1 01 and $0x1,%ecx
373: 49 0f 44 c6 cmove %r14,%rax
377: 48 8b 00 mov (%rax),%rax
37a: a8 10 test $0x10,%al
37c: 74 bc je 33a <__reset_isolation_pfn+0x21a>
37e: 49 8b 16 mov (%r14),%rdx
381: 48 89 d0 mov %rdx,%rax
384: 48 c1 ea 35 shr $0x35,%rdx
388: 48 8b 14 d7 mov (%rdi,%rdx,8),%rdx
38c: 48 c1 e8 2d shr $0x2d,%rax
390: 48 85 d2 test %rdx,%rdx
393: 74 0a je 39f <__reset_isolation_pfn+0x27f>
395: 0f b6 c0 movzbl %al,%eax
398: 48 c1 e0 04 shl $0x4,%rax
39c: 48 01 c2 add %rax,%rdx
39f: 48 8b 02 mov (%rdx),%rax
3a2: 4c 89 f2 mov %r14,%rdx
3a5: 41 b8 01 00 00 00 mov $0x1,%r8d
3ab: 31 f6 xor %esi,%esi
3ad: b9 03 00 00 00 mov $0x3,%ecx
3b2: 4c 89 f7 mov %r14,%rdi
3b5: 48 83 e0 f8 and $0xfffffffffffffff8,%rax
3b9: 48 29 c2 sub %rax,%rdx
3bc: 48 b8 b7 6d db b6 6d movabs $0x6db6db6db6db6db7,%rax
3c3: db b6 6d
3c6: 48 c1 fa 03 sar $0x3,%rdx
3ca: 48 0f af d0 imul %rax,%rdx
3ce: e8 00 00 00 00 callq 3d3 <__reset_isolation_pfn+0x2b3>
3cf: R_X86_64_PLT32 set_pfnblock_flags_mask-0x4
3d3: 44 0f b6 55 cc movzbl -0x34(%rbp),%r10d
3d8: e9 c7 fd ff ff jmpq 1a4 <__reset_isolation_pfn+0x84>
3dd: 49 8b 0e mov (%r14),%rcx
3e0: 48 8b 05 00 00 00 00 mov 0x0(%rip),%rax # 3e7 <__reset_isolation_pfn+0x2c7>
3e3: R_X86_64_PC32 mem_section-0x4
3e7: 48 89 ca mov %rcx,%rdx
3ea: 48 c1 ea 2d shr $0x2d,%rdx
3ee: 48 85 c0 test %rax,%rax
3f1: 74 17 je 40a <__reset_isolation_pfn+0x2ea>
3f3: 48 c1 e9 35 shr $0x35,%rcx
3f7: 48 8b 04 c8 mov (%rax,%rcx,8),%rax
3fb: 48 85 c0 test %rax,%rax
3fe: 74 0a je 40a <__reset_isolation_pfn+0x2ea>
400: 0f b6 d2 movzbl %dl,%edx
403: 48 c1 e2 04 shl $0x4,%rdx
407: 48 01 d0 add %rdx,%rax
40a: 48 8b 00 mov (%rax),%rax
40d: 4c 89 f6 mov %r14,%rsi
410: b9 01 00 00 00 mov $0x1,%ecx
415: ba 03 00 00 00 mov $0x3,%edx
41a: 4c 89 f7 mov %r14,%rdi
41d: 44 88 55 cb mov %r10b,-0x35(%rbp)
421: 48 83 e0 f8 and $0xfffffffffffffff8,%rax
425: 48 29 c6 sub %rax,%rsi
428: 48 b8 b7 6d db b6 6d movabs $0x6db6db6db6db6db7,%rax
42f: db b6 6d
432: 48 c1 fe 03 sar $0x3,%rsi
436: 48 0f af f0 imul %rax,%rsi
43a: e8 00 00 00 00 callq 43f <__reset_isolation_pfn+0x31f>
43b: R_X86_64_PLT32 get_pfnblock_flags_mask-0x4
43f: 44 0f b6 55 cb movzbl -0x35(%rbp),%r10d
444: 48 85 c0 test %rax,%rax
447: 0f 85 10 fe ff ff jne 25d <__reset_isolation_pfn+0x13d>
44d: e9 52 fd ff ff jmpq 1a4 <__reset_isolation_pfn+0x84>
452: 48 81 fe 00 00 08 00 cmp $0x80000,%rsi
459: 0f 84 42 fd ff ff je 1a1 <__reset_isolation_pfn+0x81>
45f: 48 8b 3d 00 00 00 00 mov 0x0(%rip),%rdi # 466 <__reset_isolation_pfn+0x346>
462: R_X86_64_PC32 mem_section-0x4
466: 48 85 ff test %rdi,%rdi
469: 0f 85 88 fe ff ff jne 2f7 <__reset_isolation_pfn+0x1d7>
46f: e9 2d fd ff ff jmpq 1a1 <__reset_isolation_pfn+0x81>
474: 49 8b 06 mov (%r14),%rax
477: 48 89 c2 mov %rax,%rdx
47a: 48 c1 e8 35 shr $0x35,%rax
47e: 48 8b 04 c7 mov (%rdi,%rax,8),%rax
482: 48 c1 ea 2d shr $0x2d,%rdx
486: 48 85 c0 test %rax,%rax
489: 74 0a je 495 <__reset_isolation_pfn+0x375>
48b: 0f b6 d2 movzbl %dl,%edx
48e: 48 c1 e2 04 shl $0x4,%rdx
492: 48 01 d0 add %rdx,%rax
495: 48 8b 00 mov (%rax),%rax
498: 4c 89 f2 mov %r14,%rdx
49b: 41 b8 01 00 00 00 mov $0x1,%r8d
4a1: 31 f6 xor %esi,%esi
4a3: b9 03 00 00 00 mov $0x3,%ecx
4a8: 4c 89 f7 mov %r14,%rdi
4ab: 48 83 e0 f8 and $0xfffffffffffffff8,%rax
4af: 48 29 c2 sub %rax,%rdx
4b2: 48 b8 b7 6d db b6 6d movabs $0x6db6db6db6db6db7,%rax
4b9: db b6 6d
4bc: 48 c1 fa 03 sar $0x3,%rdx
4c0: 48 0f af d0 imul %rax,%rdx
4c4: e8 00 00 00 00 callq 4c9 <__reset_isolation_pfn+0x3a9>
4c5: R_X86_64_PLT32 set_pfnblock_flags_mask-0x4
4c9: 45 89 ea mov %r13d,%r10d
4cc: e9 d3 fc ff ff jmpq 1a4 <__reset_isolation_pfn+0x84>
4d1: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1)
4d8: 00 00 00 00
4dc: 0f 1f 40 00 nopl 0x0(%rax)
