From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yk0-f174.google.com (mail-yk0-f174.google.com [209.85.160.174]) by kanga.kvack.org (Postfix) with ESMTP id 9C1B46B0038 for ; Fri, 20 Mar 2015 11:08:53 -0400 (EDT) Received: by ykcn8 with SMTP id n8so43636572ykc.3 for ; Fri, 20 Mar 2015 08:08:53 -0700 (PDT) Received: from userp1040.oracle.com (userp1040.oracle.com. [156.151.31.81]) by mx.google.com with ESMTPS id d27si2268289yho.12.2015.03.20.08.07.56 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 20 Mar 2015 08:08:26 -0700 (PDT) Message-ID: <550C37C9.2060200@oracle.com> Date: Fri, 20 Mar 2015 09:07:53 -0600 From: David Ahern MIME-Version: 1.0 Subject: 4.0.0-rc4: panic in free_block Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: linux-mm@kvack.org Cc: LKML , Linus Torvalds 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: 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: 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 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(): /opt/dahern/linux.git/kbuild/../mm/slab.c:3265 55de64: 10 68 00 47 b %xcc, 55df80 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@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org