From: Gerald Schaefer Date: Mon, 18 Sep 2017 14:10:35 +0000 (+0200) Subject: s390/mm: make pmdp_invalidate() do invalidation only X-Git-Tag: v4.14~281^2~3 X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=91c575b335766effa6103eba42a82aea560c365f;p=mirror_ubuntu-bionic-kernel.git s390/mm: make pmdp_invalidate() do invalidation only 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") Cc: # v4.6+ Signed-off-by: Gerald Schaefer Signed-off-by: Martin Schwidefsky --- diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index dce708e061ea..20e75a2ca93a 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -1507,7 +1507,9 @@ static inline pmd_t pmdp_huge_clear_flush(struct vm_area_struct *vma, 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