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| author | Jaewon Kim <jaewon31.kim@samsung.com> | 2020-04-10 23:32:48 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-04-11 00:36:21 +0200 |
| commit | 09ef5283fd96ac424ef0e569626f359bf9ab86c9 (patch) | |
| tree | 5f266bca26ab77e3e1bcce02ba67a0ab3bbec263 /mm | |
| parent | mm: hugetlb: optionally allocate gigantic hugepages using cma (diff) | |
| download | linux-09ef5283fd96ac424ef0e569626f359bf9ab86c9.tar.xz linux-09ef5283fd96ac424ef0e569626f359bf9ab86c9.zip | |
mm/mmap.c: initialize align_offset explicitly for vm_unmapped_area
On passing requirement to vm_unmapped_area, arch_get_unmapped_area and
arch_get_unmapped_area_topdown did not set align_offset. Internally on
both unmapped_area and unmapped_area_topdown, if info->align_mask is 0,
then info->align_offset was meaningless.
But commit df529cabb7a2 ("mm: mmap: add trace point of
vm_unmapped_area") always prints info->align_offset even though it is
uninitialized.
Fix this uninitialized value issue by setting it to 0 explicitly.
Before:
vm_unmapped_area: addr=0x755b155000 err=0 total_vm=0x15aaf0 flags=0x1 len=0x109000 lo=0x8000 hi=0x75eed48000 mask=0x0 ofs=0x4022
After:
vm_unmapped_area: addr=0x74a4ca1000 err=0 total_vm=0x168ab1 flags=0x1 len=0x9000 lo=0x8000 hi=0x753d94b000 mask=0x0 ofs=0x0
Signed-off-by: Jaewon Kim <jaewon31.kim@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michel Lespinasse <walken@google.com>
Cc: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20200409094035.19457-1-jaewon31.kim@samsung.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/mmap.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index 8d77dbbb80fe..de07bbc0e21f 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2123,6 +2123,7 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr, info.low_limit = mm->mmap_base; info.high_limit = mmap_end; info.align_mask = 0; + info.align_offset = 0; return vm_unmapped_area(&info); } #endif @@ -2164,6 +2165,7 @@ arch_get_unmapped_area_topdown(struct file *filp, unsigned long addr, info.low_limit = max(PAGE_SIZE, mmap_min_addr); info.high_limit = arch_get_mmap_base(addr, mm->mmap_base); info.align_mask = 0; + info.align_offset = 0; addr = vm_unmapped_area(&info); /* |