I can easily reproduce the panic below doing a kernel build with make -j
N, N=128, 256, etc. This is a 1024 cpu system running 4.0.0-rc4.
The top 3 frames are consistently:
free_block+0x60
cache_flusharray+0xac
kmem_cache_free+0xfc
After that one path has been from __mmdrop and the others are like
below, from remove_vma.
Unable to handle kernel paging request at virtual address 0006100000000000
tsk->{mm,active_mm}->context = 00000000000000ce
tsk->{mm,active_mm}->pgd = fff8803b56698000
\|/ ____ \|/
"@'/ .. \`@"
/_| \__/ |_\
\__U_/
sh(173167): Oops [#1]
CPU: 760 PID: 173167 Comm: sh Not tainted 4.0.0-rc4+ #1
task: fff8803b4e928b00 ti: fff8803b51800000 task.ti: fff8803b51800000
TSTATE: 0000009911e01601 TPC: 000000000055de88 TNPC: 000000000055de8c Y:
000003f0 Not tainted
TPC: <free_block+0x60/0x16c>
g0: fff1ffef00000001 g1: fff8803b75826e00 g2: 0000000000100100 g3:
0000100000000000
g4: fff8803b4e928b00 g5: fff8803b76664000 g6: fff8803b51800000 g7:
0006000000000000
o0: 0000000000008000 o1: 0000000000000046 o2: 0000000000000023 o3:
00060100767db6a0
o4: 0000000000000000 o5: 0000000000000015 sp: fff8803b51802d11 ret_pc:
fff8803b75826e08
RPC: <0xfff8803b75826e08>
l0: 0000000000200200 l1: 0000000000c005e8 l2: 0000000000d7e2b8 l3:
fff8803b3edb4000
l4: 0000000000000007 l5: 0000000000000001 l6: 00000000000000b1 l7:
ffffffffffefffff
i0: fff8000050409c60 i1: fff8803b7738f168 i2: 000000000000003c i3:
fff8803b75826e28
i4: fff8803b51803670 i5: 0000000000000000 i6: fff8803b51802dc1 i7:
000000000055eaa4
I7: <cache_flusharray+0xac/0xf4>
Call Trace:
[000000000055eaa4] cache_flusharray+0xac/0xf4
[000000000055e66c] kmem_cache_free+0xfc/0x1ac
[000000000054139c] remove_vma+0x68/0x78
[00000000005414ac] exit_mmap+0x100/0x130
[000000000045acb4] mmput+0x50/0xe8
[000000000056c284] flush_old_exec+0x500/0x5d8
[00000000005b0614] load_elf_binary+0x254/0xff4
[000000000056ba70] search_binary_handler+0xa4/0x28c
[000000000056d068] do_execveat_common+0x44c/0x624
[000000000056d3e0] do_execve+0x34/0x48
[000000000056d40c] SyS_execve+0x18/0x2c
[0000000000406254] linux_sparc_syscall+0x34/0x44
Disabling lock debugging due to kernel taint
Caller[000000000055eaa4]: cache_flusharray+0xac/0xf4
Caller[000000000055e66c]: kmem_cache_free+0xfc/0x1ac
Caller[000000000054139c]: remove_vma+0x68/0x78
Caller[00000000005414ac]: exit_mmap+0x100/0x130
Caller[000000000045acb4]: mmput+0x50/0xe8
Caller[000000000056c284]: flush_old_exec+0x500/0x5d8
Caller[00000000005b0614]: load_elf_binary+0x254/0xff4
Caller[000000000056ba70]: search_binary_handler+0xa4/0x28c
Caller[000000000056d068]: do_execveat_common+0x44c/0x624
Caller[000000000056d3e0]: do_execve+0x34/0x48
Caller[000000000056d40c]: SyS_execve+0x18/0x2c
Caller[0000000000406254]: linux_sparc_syscall+0x34/0x44
Caller[fff80001004134c8]: 0xfff80001004134c8
Instruction DUMP: 86230003 8730f00d 8728f006 <d658c007> 8600c007
8e0ac008 2ac1c002 c658e030 d458e028
####
objdump for free_block on the vmlinux:
vmlinux-4.0.0-rc4+: file format elf64-sparc
Disassembly of section .text:
000000000055de28 <free_block>:
free_block():
...
free_block():
/opt/dahern/linux.git/kbuild/../mm/slab.c:3265
55de64: 10 68 00 47 b %xcc, 55df80 <free_block+0x158>
55de68: 85 30 b0 02 srlx %g2, 2, %g2
clear_obj_pfmemalloc():
/opt/dahern/linux.git/kbuild/../mm/slab.c:224
55de6c: 98 0b 3f fe and %o4, -2, %o4
55de70: d8 76 40 00 stx %o4, [ %i1 ]
virt_to_head_page():
/opt/dahern/linux.git/kbuild/../include/linux/mm.h:554
55de74: c6 5c 80 00 ldx [ %l2 ], %g3
55de78: ce 5c 40 00 ldx [ %l1 ], %g7
55de7c: 86 23 00 03 sub %o4, %g3, %g3
55de80: 87 30 f0 0d srlx %g3, 0xd, %g3
55de84: 87 28 f0 06 sllx %g3, 6, %g3
test_bit():
/opt/dahern/linux.git/kbuild/../include/asm-generic/bitops/non-atomic.h:105
55de88: d6 58 c0 07 ldx [ %g3 + %g7 ], %o3
virt_to_head_page():
/opt/dahern/linux.git/kbuild/../include/linux/mm.h:554
55de8c: 86 00 c0 07 add %g3, %g7, %g3
...
Let me know if you need anything else.
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>