iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

mm: page_vma_mapped_walk(): crossing page table boundary

Browse Source 
page_vma_mapped_walk() cleanup: adjust the test for crossing page table
boundary - I believe pvmw->address is always page-aligned, but nothing
else here assumed that; and remember to reset pvmw->pte to NULL after
unmapping the page table, though I never saw any bug from that.

Link: https://lkml.kernel.org/r/799b3f9c-2a9e-dfef-5d89-26e9f76fd97@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Wang Yugui <wangyugui@e16-tech.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Hugh Dickins 2021-06-24 18:39:14 -07:00 committed by Linus Torvalds
parent e2e1d4076c
commit 4482824874
1 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
mm/page_vma_mapped.c
View File

@ -244,16 +244,16 @@ next_pte:
if (pvmw->address >= end)
return not_found(pvmw);
/* Did we cross page table boundary? */
if (pvmw->address % PMD_SIZE == 0) {
pte_unmap(pvmw->pte);
if ((pvmw->address & (PMD_SIZE - PAGE_SIZE)) == 0) {
if (pvmw->ptl) {
spin_unlock(pvmw->ptl);
pvmw->ptl = NULL;
}
pte_unmap(pvmw->pte);
pvmw->pte = NULL;
goto restart;
} else {
pvmw->pte++;
}
pvmw->pte++;
} while (pte_none(*pvmw->pte));
if (!pvmw->ptl) {