diff options
| author | yalin wang <yalin.wang2010@gmail.com> | 2016-01-21 16:40:30 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-01-21 17:20:51 -0800 |
| commit | 16fd0fe4aa92d0d621ecfe21de86f7fdcfa41947 (patch) | |
| tree | d94d862bb32b160dcacb5467c099f52748f5f1dd | |
| parent | 7162a1e87b3e380133dadc7909081bb70d0a7041 (diff) | |
mm: fix kernel crash in khugepaged thread
This crash is caused by NULL pointer deference, in page_to_pfn() marco,
when page == NULL :
Unable to handle kernel NULL pointer dereference at virtual address 00000000
Internal error: Oops: 94000006 [#1] SMP
Modules linked in:
CPU: 1 PID: 26 Comm: khugepaged Tainted: G W 4.3.0-rc6-next-20151022ajb-00001-g32f3386-dirty #3
PC is at khugepaged+0x378/0x1af8
LR is at khugepaged+0x418/0x1af8
Process khugepaged (pid: 26, stack limit = 0xffffffc079638020)
Call trace:
khugepaged+0x378/0x1af8
kthread+0xdc/0xf4
ret_from_fork+0xc/0x40
Code: 35001700 f0002c60 aa0703e3 f9009fa0 (f94000e0)
---[ end trace 637503d8e28ae69e ]---
Kernel panic - not syncing: Fatal exception
CPU2: stopping
CPU: 2 PID: 0 Comm: swapper/2 Tainted: G D W 4.3.0-rc6-next-20151022ajb-00001-g32f3386-dirty #3
Hardware name: linux,dummy-virt (DT)
[akpm@linux-foundation.org: fix fat-fingered merge resolution]
Signed-off-by: yalin wang <yalin.wang2010@gmail.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/trace/events/huge_memory.h | 12 | ||||
| -rw-r--r-- | mm/huge_memory.c | 6 |
2 files changed, 9 insertions, 9 deletions
diff --git a/include/trace/events/huge_memory.h b/include/trace/events/huge_memory.h index 0f803d2783e3..47c6212d8f3c 100644 --- a/include/trace/events/huge_memory.h +++ b/include/trace/events/huge_memory.h @@ -46,10 +46,10 @@ SCAN_STATUS TRACE_EVENT(mm_khugepaged_scan_pmd, - TP_PROTO(struct mm_struct *mm, unsigned long pfn, bool writable, + TP_PROTO(struct mm_struct *mm, struct page *page, bool writable, bool referenced, int none_or_zero, int status), - TP_ARGS(mm, pfn, writable, referenced, none_or_zero, status), + TP_ARGS(mm, page, writable, referenced, none_or_zero, status), TP_STRUCT__entry( __field(struct mm_struct *, mm) @@ -62,7 +62,7 @@ TRACE_EVENT(mm_khugepaged_scan_pmd, TP_fast_assign( __entry->mm = mm; - __entry->pfn = pfn; + __entry->pfn = page ? page_to_pfn(page) : -1; __entry->writable = writable; __entry->referenced = referenced; __entry->none_or_zero = none_or_zero; @@ -104,10 +104,10 @@ TRACE_EVENT(mm_collapse_huge_page, TRACE_EVENT(mm_collapse_huge_page_isolate, - TP_PROTO(unsigned long pfn, int none_or_zero, + TP_PROTO(struct page *page, int none_or_zero, bool referenced, bool writable, int status), - TP_ARGS(pfn, none_or_zero, referenced, writable, status), + TP_ARGS(page, none_or_zero, referenced, writable, status), TP_STRUCT__entry( __field(unsigned long, pfn) @@ -118,7 +118,7 @@ TRACE_EVENT(mm_collapse_huge_page_isolate, ), TP_fast_assign( - __entry->pfn = pfn; + __entry->pfn = page ? page_to_pfn(page) : -1; __entry->none_or_zero = none_or_zero; __entry->referenced = referenced; __entry->writable = writable; diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 2d1ffe9d0e26..fd3a07b3e6f4 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2072,7 +2072,7 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma, if (likely(writable)) { if (likely(referenced)) { result = SCAN_SUCCEED; - trace_mm_collapse_huge_page_isolate(page_to_pfn(page), none_or_zero, + trace_mm_collapse_huge_page_isolate(page, none_or_zero, referenced, writable, result); return 1; } @@ -2082,7 +2082,7 @@ static int __collapse_huge_page_isolate(struct vm_area_struct *vma, out: release_pte_pages(pte, _pte); - trace_mm_collapse_huge_page_isolate(page_to_pfn(page), none_or_zero, + trace_mm_collapse_huge_page_isolate(page, none_or_zero, referenced, writable, result); return 0; } @@ -2580,7 +2580,7 @@ out_unmap: collapse_huge_page(mm, address, hpage, vma, node); } out: - trace_mm_khugepaged_scan_pmd(mm, page_to_pfn(page), writable, referenced, + trace_mm_khugepaged_scan_pmd(mm, page, writable, referenced, none_or_zero, result); return ret; } |