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| author | Reza Arbab <arbab@linux.vnet.ibm.com> | 2017-10-03 16:15:35 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-10-03 17:54:25 -0700 |
| commit | 7d790d2da386a52cfebcf0c898ba927bece9d4ab (patch) | |
| tree | 90d5ebc5d441594d88195fe352b56036c718644a | |
| parent | 9625456cc76391b7f3f2809579126542a8ed4d39 (diff) | |
| download | linux-7d790d2da386a52cfebcf0c898ba927bece9d4ab.tar.bz2 | |
mm/device-public-memory: fix edge case in _vm_normal_page()
With device public pages at the end of my memory space, I'm getting
output from _vm_normal_page():
BUG: Bad page map in process migrate_pages pte:c0800001ffff0d06 pmd:f95d3000
addr:00007fff89330000 vm_flags:00100073 anon_vma:c0000000fa899320 mapping: (null) index:7fff8933
file: (null) fault: (null) mmap: (null) readpage: (null)
CPU: 0 PID: 13963 Comm: migrate_pages Tainted: P B OE 4.14.0-rc1-wip #155
Call Trace:
dump_stack+0xb0/0xf4 (unreliable)
print_bad_pte+0x28c/0x340
_vm_normal_page+0xc0/0x140
zap_pte_range+0x664/0xc10
unmap_page_range+0x318/0x670
unmap_vmas+0x74/0xe0
exit_mmap+0xe8/0x1f0
mmput+0xac/0x1f0
do_exit+0x348/0xcd0
do_group_exit+0x5c/0xf0
SyS_exit_group+0x1c/0x20
system_call+0x58/0x6c
The pfn causing this is the very last one. Correct the bounds check
accordingly.
Fixes: df6ad69838fc ("mm/device-public-memory: device memory cache coherent with CPU")
Link: http://lkml.kernel.org/r/1506092178-20351-1-git-send-email-arbab@linux.vnet.ibm.com
Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com>
Reviewed-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/memory.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/memory.c b/mm/memory.c index ec4e15494901..a728bed16c20 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -845,7 +845,7 @@ struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr, * vm_normal_page() so that we do not have to special case all * call site of vm_normal_page(). */ - if (likely(pfn < highest_memmap_pfn)) { + if (likely(pfn <= highest_memmap_pfn)) { struct page *page = pfn_to_page(pfn); if (is_device_public_page(page)) { |