[merged mm-stable] mm-hmm-process-pud-swap-entry-without-pud_huge.patch removed from -mm tree

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The quilt patch titled
     Subject: mm/hmm: process pud swap entry without pud_huge()
has been removed from the -mm tree.  Its filename was
     mm-hmm-process-pud-swap-entry-without-pud_huge.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/hmm: process pud swap entry without pud_huge()
Date: Mon, 18 Mar 2024 16:03:51 -0400

Swap pud entries do not always return true for pud_huge() for all archs. 
x86 and sparc (so far) allow it, but all the rest do not accept a swap
entry to be reported as pud_huge().  So it's not safe to check swap
entries within pud_huge().  Check swap entries before pud_huge(), so it
should be always safe.

This is the only place in the kernel that (IMHO, wrongly) relies on
pud_huge() to return true on pud swap entries.  The plan is to cleanup
pXd_huge() to only report non-swap mappings for all archs.

Link: https://lkml.kernel.org/r/20240318200404.448346-2-peterx@xxxxxxxxxx
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@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: 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/hmm.c |    7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

--- a/mm/hmm.c~mm-hmm-process-pud-swap-entry-without-pud_huge
+++ a/mm/hmm.c
@@ -424,7 +424,7 @@ static int hmm_vma_walk_pud(pud_t *pudp,
 	walk->action = ACTION_CONTINUE;
 
 	pud = READ_ONCE(*pudp);
-	if (pud_none(pud)) {
+	if (!pud_present(pud)) {
 		spin_unlock(ptl);
 		return hmm_vma_walk_hole(start, end, -1, walk);
 	}
@@ -435,11 +435,6 @@ static int hmm_vma_walk_pud(pud_t *pudp,
 		unsigned long *hmm_pfns;
 		unsigned long cpu_flags;
 
-		if (!pud_present(pud)) {
-			spin_unlock(ptl);
-			return hmm_vma_walk_hole(start, end, -1, walk);
-		}
-
 		i = (addr - range->start) >> PAGE_SHIFT;
 		npages = (end - addr) >> PAGE_SHIFT;
 		hmm_pfns = &range->hmm_pfns[i];
_

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





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