This is a note to let you know that I've just added the patch titled s390/mm: make pmdp_invalidate() do invalidation only to the 4.13-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: s390-mm-make-pmdp_invalidate-do-invalidation-only.patch and it can be found in the queue-4.13 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 91c575b335766effa6103eba42a82aea560c365f Mon Sep 17 00:00:00 2001 From: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx> Date: Mon, 18 Sep 2017 16:10:35 +0200 Subject: s390/mm: make pmdp_invalidate() do invalidation only From: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx> commit 91c575b335766effa6103eba42a82aea560c365f upstream. Commit 227be799c39a ("s390/mm: uninline pmdp_xxx functions from pgtable.h") inadvertently changed the behavior of pmdp_invalidate(), so that it now clears the pmd instead of just marking it as invalid. Fix this by restoring the original behavior. A possible impact of the misbehaving pmdp_invalidate() would be the MADV_DONTNEED races (see commits ced10803 and 58ceeb6b), although we should not have any negative impact on the related dirty/young flags, since those flags are not set by the hardware on s390. Fixes: 227be799c39a ("s390/mm: uninline pmdp_xxx functions from pgtable.h") Signed-off-by: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx> Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/s390/include/asm/pgtable.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -1462,7 +1462,9 @@ static inline pmd_t pmdp_huge_clear_flus static inline void pmdp_invalidate(struct vm_area_struct *vma, unsigned long addr, pmd_t *pmdp) { - pmdp_xchg_direct(vma->vm_mm, addr, pmdp, __pmd(_SEGMENT_ENTRY_EMPTY)); + pmd_t pmd = __pmd(pmd_val(*pmdp) | _SEGMENT_ENTRY_INVALID); + + pmdp_xchg_direct(vma->vm_mm, addr, pmdp, pmd); } #define __HAVE_ARCH_PMDP_SET_WRPROTECT Patches currently in stable-queue which might be from gerald.schaefer@xxxxxxxxxx are queue-4.13/s390-mm-make-pmdp_invalidate-do-invalidation-only.patch queue-4.13/s390-mm-fix-write-access-check-in-gup_huge_pmd.patch