diff options
author | Takashi Iwai <tiwai@suse.de> | 2017-11-01 17:43:20 +0100 |
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committer | Takashi Iwai <tiwai@suse.de> | 2017-11-01 17:43:20 +0100 |
commit | a53a0ab8ff725672fcb47bb9a5ef75fce45679d0 (patch) | |
tree | 75cdea78f27fdd569d72cea0b7837bbcc8d871f7 /mm/page_vma_mapped.c | |
parent | 1f20f9ff57ca23b9f5502fca85ce3977e8496cb1 (diff) | |
parent | b817d936248b9bcee8282e97fb1dda1b03c903fe (diff) | |
download | linux-a53a0ab8ff725672fcb47bb9a5ef75fce45679d0.tar.bz2 |
Merge tag 'asoc-fix-v4.14-rc7' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Fixes for v4.14
A bunch of fixes here, mostly device specific ones (the biggest one
being the revert of the hotword support for rt5514), with a couple of
core fixes for potential issues with corrupted or otherwise invalid
topology files.
Diffstat (limited to 'mm/page_vma_mapped.c')
-rw-r--r-- | mm/page_vma_mapped.c | 28 |
1 files changed, 11 insertions, 17 deletions
diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index 6a03946469a9..53afbb919a1c 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -6,17 +6,6 @@ #include "internal.h" -static inline bool check_pmd(struct page_vma_mapped_walk *pvmw) -{ - pmd_t pmde; - /* - * Make sure we don't re-load pmd between present and !trans_huge check. - * We need a consistent view. - */ - pmde = READ_ONCE(*pvmw->pmd); - return pmd_present(pmde) && !pmd_trans_huge(pmde); -} - static inline bool not_found(struct page_vma_mapped_walk *pvmw) { page_vma_mapped_walk_done(pvmw); @@ -116,6 +105,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) pgd_t *pgd; p4d_t *p4d; pud_t *pud; + pmd_t pmde; /* The only possible pmd mapping has been handled on last iteration */ if (pvmw->pmd && !pvmw->pte) @@ -148,7 +138,13 @@ restart: if (!pud_present(*pud)) return false; pvmw->pmd = pmd_offset(pud, pvmw->address); - if (pmd_trans_huge(*pvmw->pmd) || is_pmd_migration_entry(*pvmw->pmd)) { + /* + * Make sure the pmd value isn't cached in a register by the + * compiler and used as a stale value after we've observed a + * subsequent update. + */ + pmde = READ_ONCE(*pvmw->pmd); + if (pmd_trans_huge(pmde) || is_pmd_migration_entry(pmde)) { pvmw->ptl = pmd_lock(mm, pvmw->pmd); if (likely(pmd_trans_huge(*pvmw->pmd))) { if (pvmw->flags & PVMW_MIGRATION) @@ -167,17 +163,15 @@ restart: return not_found(pvmw); return true; } - } else - WARN_ONCE(1, "Non present huge pmd without pmd migration enabled!"); + } return not_found(pvmw); } else { /* THP pmd was split under us: handle on pte level */ spin_unlock(pvmw->ptl); pvmw->ptl = NULL; } - } else { - if (!check_pmd(pvmw)) - return false; + } else if (!pmd_present(pmde)) { + return false; } if (!map_pte(pvmw)) goto next_pte; |