On Thu, Jun 14, 2012 at 2:34 PM, Sasha Levin <levinsasha928@xxxxxxxxx> wrote: > On Thu, 2012-06-14 at 13:56 -0700, Yinghai Lu wrote: >> On Thu, Jun 14, 2012 at 2:50 AM, Sasha Levin <levinsasha928@xxxxxxxxx> wrote: >> > On Thu, 2012-06-14 at 12:20 +0900, Tejun Heo wrote: >> >> On Wed, Jun 13, 2012 at 11:38:55PM +0200, Sasha Levin wrote: >> >> > Hi all, >> >> > >> >> > I'm seeing the following when booting a KVM guest with 65gb of RAM, on latest linux-next. >> >> > >> >> > Note that it happens with numa=off. >> >> > >> >> > [ 0.000000] BUG: unable to handle kernel paging request at ffff88102febd948 >> >> > [ 0.000000] IP: [<ffffffff836a6f37>] __next_free_mem_range+0x9b/0x155 >> >> >> >> Can you map it back to the source line please? >> > >> > mm/memblock.c:583 >> > >> > phys_addr_t r_start = ri ? r[-1].base + r[-1].size : 0; >> > 97: 85 d2 test %edx,%edx >> > 99: 74 08 je a3 <__next_free_mem_range+0xa3> >> > 9b: 49 8b 48 f0 mov -0x10(%r8),%rcx >> > 9f: 49 03 48 e8 add -0x18(%r8),%rcx >> > >> > It's the deref on 9b (r8=ffff88102febd958). >> >> that reserved.region is allocated by memblock. >> >> can you boot with "memblock=debug debug ignore_loglevel" and post >> whole boot log? > > Attached below. I've also noticed it doesn't always happen, but > increasing the vcpu count (to something around 254) makes it happen > almost every time. > ... [ 0.000000] memblock: reserved array is doubled to 512 at [0x102febc080-0x102febf07f] [ 0.000000] memblock_free: [0x0000102febf080-0x0000102fec0880] memblock_double_array+0x1b0/0x1e2 [ 0.000000] memblock_reserve: [0x0000102febc080-0x0000102febf080] memblock_double_array+0x1c5/0x1e2 the reserved regions get double two times to 512. .... > [ 0.000000] memblock_free: [0x0000102febc080-0x0000102febf080] memblock_free_reserved_regions+0x37/0x39 > [ 0.000000] BUG: unable to handle kernel paging request at ffff88102febd948 > [ 0.000000] IP: [<ffffffff836a5774>] __next_free_mem_range+0x9b/0x155 > [ 0.000000] PGD 4826063 PUD cf67a067 PMD cf7fa067 PTE 800000102febd160 that page table for them is [ 0.000000] kernel direct mapping tables up to 0x102fffffff @ [mem 0xc7e3e000-0xcfffffff] [ 0.000000] memblock_reserve: [0x000000c7e3e000-0x000000cf7fb000] native_pagetable_reserve+0xc/0xe only near by allocation is swiotlb. [ 0.000000] __ex_table already sorted, skipping sort [ 0.000000] memblock_reserve: [0x000000c3e3e000-0x000000c7e3e000] __alloc_memory_core_early+0x5c/0x73 ... [ 0.000000] memblock_reserve: [0x000000cfff8000-0x000000d0000000] __alloc_memory_core_early+0x5c/0x73 [ 0.000000] Checking aperture... so the memblock allocation is ok... can you please boot with "memtest" to see if there is any memory problem? Thanks Yinghai -- 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