The quilt patch titled
Subject: mm/gup: cache p4d in follow_p4d_mask()
has been removed from the -mm tree. Its filename was
mm-gup-cache-p4d-in-follow_p4d_mask.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Peter Xu <peterx@xxxxxxxxxx>
Subject: mm/gup: cache p4d in follow_p4d_mask()
Date: Mon, 18 Mar 2024 16:03:52 -0400
Add a variable to cache p4d in follow_p4d_mask(). It's a good practise to
make sure all the following checks will have a consistent view of the
entry.
Link: https://lkml.kernel.org/r/20240318200404.448346-3-peterx@xxxxxxxxxx
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
Cc: Alistair Popple <apopple@xxxxxxxxxx>
Cc: Andreas Larsson <andreas@xxxxxxxxxxx>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Bjorn Andersson <andersson@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: Fabio Estevam <festevam@xxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxxxx>
Cc: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
Cc: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
Cc: Mark Salter <msalter@xxxxxxxxxx>
Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Mike Rapoport (IBM) <rppt@xxxxxxxxxx>
Cc: Muchun Song <muchun.song@xxxxxxxxx>
Cc: Naoya Horiguchi <nao.horiguchi@xxxxxxxxx>
Cc: "Naveen N. Rao" <naveen.n.rao@xxxxxxxxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/gup.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)
--- a/mm/gup.c~mm-gup-cache-p4d-in-follow_p4d_mask
+++ a/mm/gup.c
@@ -772,16 +772,17 @@ static struct page *follow_p4d_mask(stru
unsigned int flags,
struct follow_page_context *ctx)
{
- p4d_t *p4d;
+ p4d_t *p4dp, p4d;
- p4d = p4d_offset(pgdp, address);
- if (p4d_none(*p4d))
+ p4dp = p4d_offset(pgdp, address);
+ p4d = READ_ONCE(*p4dp);
+ if (p4d_none(p4d))
return no_page_table(vma, flags);
- BUILD_BUG_ON(p4d_huge(*p4d));
- if (unlikely(p4d_bad(*p4d)))
+ BUILD_BUG_ON(p4d_huge(p4d));
+ if (unlikely(p4d_bad(p4d)))
return no_page_table(vma, flags);
- return follow_pud_mask(vma, address, p4d, flags, ctx);
+ return follow_pud_mask(vma, address, p4dp, flags, ctx);
}
/**
_
Patches currently in -mm which might be from peterx@xxxxxxxxxx are
mm-userfaultfd-reset-ptes-when-close-for-wr-protected-ones.patch
mm-hugetlb-assert-hugetlb_lock-in-__hugetlb_cgroup_commit_charge.patch
mm-page_table_check-support-userfault-wr-protect-entries.patch
