The patch titled
Subject: mm: thp: pass correct vm_flags to hugepage_vma_check()
has been removed from the -mm tree. Its filename was
mm-thp-passing-correct-vm_flags-to-hugepage_vma_check.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Song Liu <songliubraving@xxxxxx>
Subject: mm: thp: pass correct vm_flags to hugepage_vma_check()
khugepaged_enter_vma_merge() passes a stale vma->vm_flags to
hugepage_vma_check(). The argument vm_flags contains the latest value.
Therefore, it is necessary to pass this vm_flags into
hugepage_vma_check().
With this bug, madvise(MADV_HUGEPAGE) for mmap files in shmem fails to
put memory in huge pages. Here is an example of failed madvise():
/* mount /dev/shm with huge=advise:
* mount -o remount,huge=advise /dev/shm */
/* create file /dev/shm/huge */
#define HUGE_FILE "/dev/shm/huge"
fd = open(HUGE_FILE, O_RDONLY);
ptr = mmap(NULL, FILE_SIZE, PROT_READ, MAP_PRIVATE, fd, 0);
ret = madvise(ptr, FILE_SIZE, MADV_HUGEPAGE);
madvise() will return 0, but this memory region is never put in huge
page (check from /proc/meminfo: ShmemHugePages).
Link: http://lkml.kernel.org/r/20180629181752.792831-1-songliubraving@xxxxxx
Fixes: 02b75dc8160d ("mm: thp: register mm for khugepaged when merging vma for shmem")
Signed-off-by: Song Liu <songliubraving@xxxxxx>
Reviewed-by: Rik van Riel <riel@xxxxxxxxxxx>
Reviewed-by: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/khugepaged.c | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)
--- a/mm/khugepaged.c~mm-thp-passing-correct-vm_flags-to-hugepage_vma_check
+++ a/mm/khugepaged.c
@@ -397,10 +397,11 @@ static inline int khugepaged_test_exit(s
return atomic_read(&mm->mm_users) == 0;
}
-static bool hugepage_vma_check(struct vm_area_struct *vma)
+static bool hugepage_vma_check(struct vm_area_struct *vma,
+ unsigned long vm_flags)
{
- if ((!(vma->vm_flags & VM_HUGEPAGE) && !khugepaged_always()) ||
- (vma->vm_flags & VM_NOHUGEPAGE) ||
+ if ((!(vm_flags & VM_HUGEPAGE) && !khugepaged_always()) ||
+ (vm_flags & VM_NOHUGEPAGE) ||
test_bit(MMF_DISABLE_THP, &vma->vm_mm->flags))
return false;
if (shmem_file(vma->vm_file)) {
@@ -413,7 +414,7 @@ static bool hugepage_vma_check(struct vm
return false;
if (is_vma_temporary_stack(vma))
return false;
- return !(vma->vm_flags & VM_NO_KHUGEPAGED);
+ return !(vm_flags & VM_NO_KHUGEPAGED);
}
int __khugepaged_enter(struct mm_struct *mm)
@@ -458,7 +459,7 @@ int khugepaged_enter_vma_merge(struct vm
* khugepaged does not yet work on non-shmem files or special
* mappings. And file-private shmem THP is not supported.
*/
- if (!hugepage_vma_check(vma))
+ if (!hugepage_vma_check(vma, vm_flags))
return 0;
hstart = (vma->vm_start + ~HPAGE_PMD_MASK) & HPAGE_PMD_MASK;
@@ -861,7 +862,7 @@ static int hugepage_vma_revalidate(struc
hend = vma->vm_end & HPAGE_PMD_MASK;
if (address < hstart || address + HPAGE_PMD_SIZE > hend)
return SCAN_ADDRESS_RANGE;
- if (!hugepage_vma_check(vma))
+ if (!hugepage_vma_check(vma, vma->vm_flags))
return SCAN_VMA_CHECK;
return 0;
}
@@ -1695,7 +1696,7 @@ static unsigned int khugepaged_scan_mm_s
progress++;
break;
}
- if (!hugepage_vma_check(vma)) {
+ if (!hugepage_vma_check(vma, vma->vm_flags)) {
skip:
progress++;
continue;
_
Patches currently in -mm which might be from songliubraving@xxxxxx are
