Just paste for you the asm here from 2.6.36.2: ffffffff81038220 <task_rq_lock>: ffffffff81038220: 48 83 ec 28 sub $0x28,%rsp ffffffff81038224: 48 89 5c 24 08 mov %rbx,0x8(%rsp) ffffffff81038229: 48 89 6c 24 10 mov %rbp,0x10(%rsp) ffffffff8103822e: 4c 89 64 24 18 mov %r12,0x18(%rsp) ffffffff81038233: 48 c7 c3 80 24 01 00 mov $0x12480,%rbx ffffffff8103823a: 4c 89 6c 24 20 mov %r13,0x20(%rsp) ffffffff8103823f: 48 89 fd mov %rdi,%rbp ffffffff81038242: 49 89 f4 mov %rsi,%r12 ffffffff81038245: ff 14 25 e0 0d 57 81 callq *0xffffffff81570de0 ffffffff8103824c: 48 89 c2 mov %rax,%rdx ffffffff8103824f: ff 14 25 f0 0d 57 81 callq *0xffffffff81570df0 ffffffff81038256: 49 89 14 24 mov %rdx,(%r12) ffffffff8103825a: 49 89 dd mov %rbx,%r13 ffffffff8103825d: 48 8b 45 08 mov 0x8(%rbp),%rax ffffffff81038261: 8b 40 18 mov 0x18(%rax),%eax ffffffff81038264: 4c 03 2c c5 a0 26 5c add -0x7ea3d960(,% rax,8),%r13 <============ PANICS ffffffff8103826b: 81 ffffffff8103826c: 4c 89 ef mov %r13,%rdi ffffffff8103826f: e8 2c ff 3c 00 callq ffffffff814081a0 <_raw_spin_lock> ffffffff81038274: 48 8b 45 08 mov 0x8(%rbp),%rax ffffffff81038278: 8b 40 18 mov 0x18(%rax),%eax ffffffff8103827b: 48 8b 04 c5 a0 26 5c mov -0x7ea3d960(,% rax,8),%rax ffffffff81038282: 81 ffffffff81038283: 48 8d 04 03 lea (%rbx,%rax,1),% rax ffffffff81038287: 49 39 c5 cmp %rax,%r13 ffffffff8103828a: 75 1c jne ffffffff810382a8 <task_rq_lock+0x88> ffffffff8103828c: 4c 89 e8 mov %r13,%rax ffffffff8103828f: 48 8b 5c 24 08 mov 0x8(%rsp),%rbx ffffffff81038294: 48 8b 6c 24 10 mov 0x10(%rsp),%rbp ffffffff81038299: 4c 8b 64 24 18 mov 0x18(%rsp),%r12 ffffffff8103829e: 4c 8b 6c 24 20 mov 0x20(%rsp),%r13 ffffffff810382a3: 48 83 c4 28 add $0x28,%rsp ffffffff810382a7: c3 retq ffffffff810382a8: 49 8b 34 24 mov (%r12),%rsi ffffffff810382ac: 4c 89 ef mov %r13,%rdi ffffffff810382af: e8 9c 03 3d 00 callq ffffffff81408650 <_raw_spin_unlock_irqrestore> ffffffff810382b4: eb 8f jmp ffffffff81038245 <task_rq_lock+0x25> ffffffff810382b6: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,% rax,1) ffffffff810382bd: 00 00 00 looks like a bogus value in RAX, then page fault in kernel space => panics. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>