Le 03/03/2011 16:55, Michael S. Tsirkin a écrit : > On Thu, Mar 03, 2011 at 04:26:11PM +0100, Jean-Philippe Menil wrote: >> Le 03/03/2011 15:47, Michael S. Tsirkin a écrit : >>> On Tue, Mar 01, 2011 at 03:39:12PM +0100, Jean-Philippe Menil wrote: >>>> so this time the bug is: >>>> >>>> [17882.612303] BUG: unable to handle kernel paging request at >>>> 0000000000002458 >>>> [17882.612342] IP: [<ffffffffa03898a0>] kvm_set_irq+0x30/0x140 [kvm] >>>> >>>> markup_oops give me this: >>>> >>>> root@ayrshire:~# cat bug-0103.txt | perl markup_oops.pl -m >>>> /lib/modules/2.6.37.2-dsiun-110105+/kernel/arch/x86/kvm/kvm.ko >>>> /boot/vmlinuz-2.6.37.2-dsiun-110105+ >>>> vmaoffset = 18446744072102621184 ffffffffa0389871: 48 89 e5 mov >>>> %rsp,%rbp >>>> ffffffffa0389874: 41 57 push %r15 >>>> ffffffffa0389876: 41 89 cf mov %ecx,%r15d | %r15 >>>> => 1 %ecx = 1 >>>> ffffffffa0389879: 41 56 push %r14 | %r14 >>>> => ffffffffa038aad0 >>>> ffffffffa038987b: 41 55 push %r13 >>>> ffffffffa038987d: 49 89 fd mov %rdi,%r13 | %edi >>>> = 0 %r13 => 0 >>>> ffffffffa0389880: 41 54 push %r12 | %r12 => 0 >>>> ffffffffa0389882: 53 push %rbx >>>> ffffffffa0389883: 89 d3 mov %edx,%ebx | %ebx => 1a >>>> ffffffffa0389885: 48 81 ec a8 00 00 00 sub $0xa8,%rsp >>>> ffffffffa038988c: 8b 15 00 00 00 00 mov 0x0(%rip),%edx >>>> # ffffffffa0389892<kvm_set_irq+0x22> >>>> ffffffffa0389892: 89 b5 3c ff ff ff mov %esi,-0xc4(%rbp) | >>>> %esi = 0 >>>> ffffffffa0389898: 85 d2 test %edx,%edx | %edx => 0 >>>> ffffffffa038989a: 0f 85 d5 00 00 00 jne ffffffffa0389975 >>>> <kvm_set_irq+0x105> >>>> *ffffffffa03898a0: 49 8b 85 58 24 00 00 mov 0x2458(%r13),%rax | >>>> %eax = 0 %r13 = 0<--- faulting instruction >>>> ffffffffa03898a7: 3b 98 28 01 00 00 cmp 0x128(%rax),%ebx >>>> ffffffffa03898ad: 73 61 jae ffffffffa0389910 >>>> <kvm_set_irq+0xa0> >>>> ffffffffa03898af: 89 db mov %ebx,%ebx >>>> ffffffffa03898b1: 48 8b 84 d8 30 01 00 mov 0x130(%rax,%rbx,8),%rax >>>> ffffffffa03898b8: 00 >>>> ffffffffa03898b9: 48 85 c0 test %rax,%rax >>>> ffffffffa03898bc: 74 52 je ffffffffa0389910 >>>> <kvm_set_irq+0xa0> >>>> ffffffffa03898be: 48 8d 95 40 ff ff ff lea -0xc0(%rbp),%rdx >>>> ffffffffa03898c5: 31 db xor %ebx,%ebx >>>> ffffffffa03898c7: 48 8b 08 mov (%rax),%rcx >>>> ffffffffa03898ca: 83 c3 01 add $0x1,%ebx >>>> ffffffffa03898cd: 0f 18 09 prefetcht0 (%rcx) >>>> ffffffffa03898d0: 48 8b 48 e0 mov -0x20(%rax),%rcx >>>> ffffffffa03898d4: 48 89 0a mov %rcx,(%rdx) >>>> ffffffffa03898d7: 48 8b 48 e8 mov -0x18(%rax),%rcx >>>> ffffffffa03898db: 48 89 4a 08 mov %rcx,0x8(%rdx) >>>> ffffffffa03898df: 48 8b 48 f0 mov -0x10(%rax),%rcx >>>> ffffffffa03898e3: 48 89 4a 10 mov %rcx,0x10(%rdx) >>>> ffffffffa03898e7: 48 8b 48 f8 mov -0x8(%rax),%rcx >>>> ffffffffa03898eb: 48 89 4a 18 mov %rcx,0x18(%rdx) >>>> >>>> wich correspond to offset 68a0 (from objdump): >>>> >>>> kvm_set_irq(): >>>> /usr/src/GIT/linux-2.6-stable/arch/x86/kvm/../../../virt/kvm/irq_comm.c:161 >>>> 68a0: 49 8b 85 58 24 00 00 mov 0x2458(%r13),%rax >>>> /usr/src/GIT/linux-2.6-stable/arch/x86/kvm/../../../virt/kvm/irq_comm.c:162 >>>> 68a7: 3b 98 28 01 00 00 cmp 0x128(%rax),%ebx >>>> >>>> root@ayrshire:~# addr2line -e >>>> /lib/modules/2.6.37.2-dsiun-110105+/kernel/arch/x86/kvm/kvm.ko >>>> 0x68a0 >>>> /usr/src/GIT/linux-2.6-stable/arch/x86/kvm/../../../virt/kvm/irq_comm.c:161 >>>> >>>> So here kvm->irq_routing is null. >>>> >>>> How can it be? >>>> >>>> Regards. >>> Not null, this seems to be invalid. >>> I suspect use after free where the kvm pointer is >>> pointing at some random memory. Use after free? >>> Could you please try enabling a slab debugger, >>> recompile and rerun the test? >>> >> Hi, >> >> I'm not sure to activate the right thing. >> Is that what you want? >> >> CONFIG_SLAB=y >> CONFIG_SLABINFO=y >> CONFIG_DEBUG_SLAB=y >> CONFIG_DEBUG_SLAB_LEAK=y >> >> Regards. > Yes, maybe disable SLAB_LEAK. > >> -- >> Jean-Philippe Menil - Pôle réseau Service IRTS >> DSI Université de Nantes >> jean-philippe.menil@xxxxxxxxxxxxxx >> Tel : 02.53.48.49.27 - Fax : 02.53.48.49.09 > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html Hi, so this time, here is what markup_oops says: root@ayrshire:~# cat oops-0403.txt | perl markup_oops.pl -m /lib/modules/2.6.37.2.999-dsiun-110105+/kernel/arch/x86/kvm/kvm.ko /boot/vmlinuz-2.6.37.2.999-dsiun-110105+ vmaoffset = 18446744072102948864 ffffffffa03d9811: 48 89 e5 mov %rsp,%rbp ffffffffa03d9814: 41 57 push %r15 ffffffffa03d9816: 41 89 cf mov %ecx,%r15d | %r15 => 1 %ecx = 1 ffffffffa03d9819: 41 56 push %r14 | %r14 => ffffffffa03daa50 ffffffffa03d981b: 41 55 push %r13 ffffffffa03d981d: 49 89 fd mov %rdi,%r13 | %edi = 6b6b6b6b6b6b6b6b %r13 => 6b6b6b6b6b6b6b6b ffffffffa03d9820: 41 54 push %r12 | %r12 => 6b6b6b6b6b6b6b6b ffffffffa03d9822: 53 push %rbx ffffffffa03d9823: 89 d3 mov %edx,%ebx | %ebx => 6b6b6b6b ffffffffa03d9825: 48 81 ec a8 00 00 00 sub $0xa8,%rsp ffffffffa03d982c: 8b 15 00 00 00 00 mov 0x0(%rip),%edx # ffffffffa03d9832 <kvm_set_irq+0x22> ffffffffa03d9832: 89 b5 3c ff ff ff mov %esi,-0xc4(%rbp) | %esi = 0 ffffffffa03d9838: 85 d2 test %edx,%edx | %edx => 0 ffffffffa03d983a: 0f 85 d5 00 00 00 jne ffffffffa03d9915 <kvm_set_irq+0x105> *ffffffffa03d9840: 49 8b 85 58 24 00 00 mov 0x2458(%r13),%rax | %eax = 0 %r13 = 6b6b6b6b6b6b6b6b <--- faulting instruction ffffffffa03d9847: 3b 98 28 01 00 00 cmp 0x128(%rax),%ebx ffffffffa03d984d: 73 61 jae ffffffffa03d98b0 <kvm_set_irq+0xa0> ffffffffa03d984f: 89 db mov %ebx,%ebx ffffffffa03d9851: 48 8b 84 d8 30 01 00 mov 0x130(%rax,%rbx,8),%rax ffffffffa03d9858: 00 ffffffffa03d9859: 48 85 c0 test %rax,%rax ffffffffa03d985c: 74 52 je ffffffffa03d98b0 <kvm_set_irq+0xa0> ffffffffa03d985e: 48 8d 95 40 ff ff ff lea -0xc0(%rbp),%rdx ffffffffa03d9865: 31 db xor %ebx,%ebx ffffffffa03d9867: 48 8b 08 mov (%rax),%rcx ffffffffa03d986a: 83 c3 01 add $0x1,%ebx ffffffffa03d986d: 0f 18 09 prefetcht0 (%rcx) ffffffffa03d9870: 48 8b 48 e0 mov -0x20(%rax),%rcx ffffffffa03d9874: 48 89 0a mov %rcx,(%rdx) ffffffffa03d9877: 48 8b 48 e8 mov -0x18(%rax),%rcx ffffffffa03d987b: 48 89 4a 08 mov %rcx,0x8(%rdx) ffffffffa03d987f: 48 8b 48 f0 mov -0x10(%rax),%rcx ffffffffa03d9883: 48 89 4a 10 mov %rcx,0x10(%rdx) ffffffffa03d9887: 48 8b 48 f8 mov -0x8(%rax),%rcx ffffffffa03d988b: 48 89 4a 18 mov %rcx,0x18(%rdx) Is that you wanted, the "6b6b6b6b6b6b6b6b" ? Regards. -- Jean-Philippe Menil - Pôle réseau Service IRTS DSI Université de Nantes jean-philippe.menil@xxxxxxxxxxxxxx Tel : 02.53.48.49.27 - Fax : 02.53.48.49.09 _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization