On Fri, Nov 13, 2015 at 01:18:09PM +0100, Vlastimil Babka wrote: > On 11/13/2015 01:07 PM, yalin wang wrote: > >This crash is caused by NULL pointer deference, in page_to_pfn() marco, > >when page == NULL : > > > >[ 182.639154 ] Unable to handle kernel NULL pointer dereference at virtual address 00000000 > >[ 182.639491 ] pgd = ffffffc00077a000 > >[ 182.639761 ] [00000000] *pgd=00000000b9422003, *pud=00000000b9422003, *pmd=00000000b9423003, *pte=0060000008000707 > >[ 182.640749 ] Internal error: Oops: 94000006 [#1] SMP > >[ 182.641197 ] Modules linked in: > >[ 182.641580 ] CPU: 1 PID: 26 Comm: khugepaged Tainted: G W 4.3.0-rc6-next-20151022ajb-00001-g32f3386-dirty #3 > >[ 182.642077 ] Hardware name: linux,dummy-virt (DT) > >[ 182.642227 ] task: ffffffc07957c080 ti: ffffffc079638000 task.ti: ffffffc079638000 > >[ 182.642598 ] PC is at khugepaged+0x378/0x1af8 > >[ 182.642826 ] LR is at khugepaged+0x418/0x1af8 > >[ 182.643047 ] pc : [<ffffffc0001980ac>] lr : [<ffffffc00019814c>] pstate: 60000145 > >[ 182.643490 ] sp : ffffffc07963bca0 > >[ 182.643650 ] x29: ffffffc07963bca0 x28: ffffffc00075c000 > >[ 182.644024 ] x27: ffffffc00f275040 x26: ffffffc0006c7000 > >[ 182.644334 ] x25: 00e8000048800f51 x24: 0000000006400000 > >[ 182.644687 ] x23: 0000000000000002 x22: 0000000000000000 > >[ 182.644972 ] x21: 0000000000000000 x20: 0000000000000000 > >[ 182.645446 ] x19: 0000000000000000 x18: 0000007ff86d0990 > >[ 182.645931 ] x17: 00000000007ef9c8 x16: ffffffc000098390 > >[ 182.646236 ] x15: ffffffffffffffff x14: 00000000ffffffff > >[ 182.646649 ] x13: 000000000000016a x12: 0000000000000000 > >[ 182.647046 ] x11: ffffffc07f025020 x10: 0000000000000000 > >[ 182.647395 ] x9 : 0000000000000048 x8 : ffffffc000721e28 > >[ 182.647872 ] x7 : 0000000000000000 x6 : ffffffc07f02d000 > >[ 182.648261 ] x5 : fffffffffffffe00 x4 : ffffffc00f275040 > >[ 182.648611 ] x3 : 0000000000000000 x2 : ffffffc00f2ad000 > >[ 182.648908 ] x1 : 0000000000000000 x0 : ffffffc000727000 > >[ 182.649147 ] > >[ 182.649252 ] Process khugepaged (pid: 26, stack limit = 0xffffffc079638020) > >[ 182.649724 ] Stack: (0xffffffc07963bca0 to 0xffffffc07963c000) > >[ 182.650141 ] bca0: ffffffc07963be30 ffffffc0000b5044 ffffffc07961fb80 ffffffc00072e630 > >[ 182.650587 ] bcc0: ffffffc0005d5090 0000000000000000 ffffffc000197d34 0000000000000000 > >[ 182.651009 ] bce0: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > >[ 182.651446 ] bd00: ffffffc07963bd90 ffffffc07f1cbf80 000000004f3be003 ffffffc00f2750a4 > >[ 182.651956 ] bd20: ffffffc00f3bf000 ffffffc000000001 0000000000000001 ffffffc07f085740 > >[ 182.652520 ] bd40: ffffffc00f2ad188 ffffffc000000000 0000000006200000 ffffffc00f275040 > >[ 182.652972 ] bd60: ffffffc0006b1a90 ffffffc079638000 ffffffc07963be20 ffffffc00f0144d0 > >[ 182.653357 ] bd80: ffffffc000000000 0000000006400000 ffffffc00f0144d0 00000a0800000001 > >[ 182.653793 ] bda0: 0000100000000001 ffffffc000000001 ffffffc07f025000 ffffffc00f2750a8 > >[ 182.654226 ] bdc0: 00000001000005f8 ffffffc00075a000 0000000006a00000 ffffffc000727000 > >[ 182.654522 ] bde0: ffffffc0006e8478 ffffffc000000000 0000000100000000 ffffffc078fb9000 > >[ 182.654869 ] be00: ffffffc07963be30 ffffffc000000000 ffffffc07957c080 ffffffc0000cfc4c > >[ 182.655225 ] be20: ffffffc07963be20 ffffffc07963be20 0000000000000000 ffffffc000085c50 > >[ 182.655588 ] be40: ffffffc0000b4f64 ffffffc07961fb80 0000000000000000 0000000000000000 > >[ 182.656138 ] be60: 0000000000000000 ffffffc0000bee2c ffffffc0000b4f64 0000000000000000 > >[ 182.656609 ] be80: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > >[ 182.657145 ] bea0: ffffffc07963bea0 ffffffc07963bea0 0000000000000000 ffffffc000000000 > >[ 182.657475 ] bec0: ffffffc07963bec0 ffffffc07963bec0 0000000000000000 0000000000000000 > >[ 182.657922 ] bee0: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > >[ 182.658558 ] bf00: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > >[ 182.658972 ] bf20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > >[ 182.659291 ] bf40: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > >[ 182.659722 ] bf60: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > >[ 182.660122 ] bf80: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > >[ 182.660654 ] bfa0: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > >[ 182.661064 ] bfc0: 0000000000000000 0000000000000000 0000000000000000 0000000000000005 > >[ 182.661466 ] bfe0: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 > >[ 182.661848 ] Call trace: > >[ 182.662050 ] [<ffffffc0001980ac>] khugepaged+0x378/0x1af8 > >[ 182.662294 ] [<ffffffc0000b5040>] kthread+0xdc/0xf4 > >[ 182.662605 ] [<ffffffc000085c4c>] ret_from_fork+0xc/0x40 > >[ 182.663046 ] Code: 35001700 f0002c60 aa0703e3 f9009fa0 (f94000e0) > >[ 182.663901 ] ---[ end trace 637503d8e28ae69e ]--- > >[ 182.664160 ] Kernel panic - not syncing: Fatal exception > >[ 182.664571 ] CPU2: stopping > >[ 182.664794 ] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G D W 4.3.0-rc6-next-20151022ajb-00001-g32f3386-dirty #3 > >[ 182.665248 ] Hardware name: linux,dummy-virt (DT) > > > >Signed-off-by: yalin wang <yalin.wang2010@xxxxxxxxx> > > This is a fix for: > http://www.ozlabs.org/~akpm/mmots/broken-out/mm-add-tracepoint-for-scanning-pages.patch > > Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> -- Kirill A. Shutemov -- 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>