Hi Yalin, I'm seeing the following BUG when booting the latest -next kernel. I've bisected it down to "mm/cma.c: free the reserved memblock when free cma pages". [ 2.438701] BUG: unable to handle kernel paging request at ffff880972493000 [ 2.438701] IP: memblock_isolate_range (mm/memblock.c:624) [ 2.438701] PGD 34b51067 PUD 34b54067 PMD 976c56067 PTE 8000000972493060 [ 2.438701] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC [ 2.438701] Dumping ftrace buffer: [ 2.438701] (ftrace buffer empty) [ 2.438701] Modules linked in: [ 2.438701] CPU: 17 PID: 1 Comm: swapper/0 Not tainted 3.17.0-rc6-next-20140923-sasha-00037-gc40eca4 #1213 [ 2.438701] task: ffff88076d7d0000 ti: ffff880048d40000 task.ti: ffff880048d40000 [ 2.438701] RIP: memblock_isolate_range (mm/memblock.c:624) [ 2.438701] RSP: 0000:ffff880048d43cf8 EFLAGS: 00010286 [ 2.438828] RAX: ffff880972493000 RBX: 0000000962600000 RCX: ffff880048d43d50 [ 2.439590] RDX: 0000000000200000 RSI: 0000000962400000 RDI: ffffffffb2fcaa30 [ 2.440000] RBP: ffff880048d43d38 R08: ffff880048d43d54 R09: 0000000000000001 [ 2.440000] R10: 0000000000000000 R11: 0000000000000001 R12: ffff880048d43d54 [ 2.440000] R13: 0000000962400000 R14: 0000000000000000 R15: ffffffffb2fcaa30 [ 2.440000] FS: 0000000000000000(0000) GS:ffff880567c00000(0000) knlGS:0000000000000000 [ 2.440000] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 2.440000] CR2: ffff880972493000 CR3: 0000000031e2f000 CR4: 00000000000006a0 [ 2.440000] Stack: [ 2.440000] ffffffffad29cda2 ffff880048d43d50 ffffea002eeb4000 0000000962400000 [ 2.440000] ffffffffb2fcaa30 0000000000000000 000000000000a000 ffffea002eeb4008 [ 2.440000] ffff880048d43d68 ffffffffb049e64a 0000000962400000 0000000000000000 [ 2.440000] Call Trace: [ 2.440000] ? adjust_managed_page_count (mm/page_alloc.c:5430) [ 2.440000] memblock_remove_range (mm/memblock.c:672) [ 2.440000] memblock_free (mm/memblock.c:695) [ 2.440000] init_cma_reserved_pageblock (mm/page_alloc.c:840) [ 2.440000] cma_init_reserved_areas (mm/cma.c:118 mm/cma.c:133) [ 2.440000] ? kfree (mm/slub.c:2674 mm/slub.c:3339) [ 2.440000] ? early_memunmap (mm/cma.c:129) [ 2.440000] do_one_initcall (init/main.c:792) [ 2.440000] kernel_init_freeable (init/main.c:857 init/main.c:865 init/main.c:884 init/main.c:1005) [ 2.440000] ? rest_init (init/main.c:932) [ 2.440000] kernel_init (init/main.c:937) [ 2.440000] ret_from_fork (arch/x86/kernel/entry_64.S:348) [ 2.440000] ? rest_init (init/main.c:932) [ 2.440000] Code: 89 ff e8 ec fa ff ff 85 c0 79 e1 b8 f4 ff ff ff e9 c0 00 00 00 4c 01 eb 45 31 f6 49 63 c6 49 3b 07 73 b9 48 c1 e0 05 49 03 47 18 <48> 8b 10 48 8b 48 08 48 8d 34 11 48 39 d3 76 a1 49 39 f5 0f 83 All code ======== 0: 89 ff mov %edi,%edi 2: e8 ec fa ff ff callq 0xfffffffffffffaf3 7: 85 c0 test %eax,%eax 9: 79 e1 jns 0xffffffffffffffec b: b8 f4 ff ff ff mov $0xfffffff4,%eax 10: e9 c0 00 00 00 jmpq 0xd5 15: 4c 01 eb add %r13,%rbx 18: 45 31 f6 xor %r14d,%r14d 1b: 49 63 c6 movslq %r14d,%rax 1e: 49 3b 07 cmp (%r15),%rax 21: 73 b9 jae 0xffffffffffffffdc 23: 48 c1 e0 05 shl $0x5,%rax 27: 49 03 47 18 add 0x18(%r15),%rax 2b:* 48 8b 10 mov (%rax),%rdx <-- trapping instruction 2e: 48 8b 48 08 mov 0x8(%rax),%rcx 32: 48 8d 34 11 lea (%rcx,%rdx,1),%rsi 36: 48 39 d3 cmp %rdx,%rbx 39: 76 a1 jbe 0xffffffffffffffdc 3b: 49 39 f5 cmp %rsi,%r13 3e: 0f .byte 0xf 3f: 83 .byte 0x83 ... Code starting with the faulting instruction =========================================== 0: 48 8b 10 mov (%rax),%rdx 3: 48 8b 48 08 mov 0x8(%rax),%rcx 7: 48 8d 34 11 lea (%rcx,%rdx,1),%rsi b: 48 39 d3 cmp %rdx,%rbx e: 76 a1 jbe 0xffffffffffffffb1 10: 49 39 f5 cmp %rsi,%r13 13: 0f .byte 0xf 14: 83 .byte 0x83 ... [ 2.440000] RIP memblock_isolate_range (mm/memblock.c:624) [ 2.440000] RSP <ffff880048d43cf8> [ 2.440000] CR2: ffff880972493000 Thanks, Sasha -- 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>
