mremap: move_ptes: check pte dirty after its removal
Linus found there still is a race in mremap after commit 5d1904204c99
("mremap: fix race between mremap() and page cleanning").
As described by Linus:
"the issue is that another thread might make the pte be dirty (in the
hardware walker, so no locking of ours will make any difference)
*after* we checked whether it was dirty, but *before* we removed it
from the page tables"
Fix it by moving the check after we removed it from the page table.
Suggested-by: Linus Torvalds <firstname.lastname@example.org>
Signed-off-by: Aaron Lu <email@example.com>
Signed-off-by: Linus Torvalds <firstname.lastname@example.org>
2 files changed