FAILED: patch "[PATCH] mm/rmap: fix two comments related to huge_pmd_unshare()" failed to apply to 6.1-stable tree
Subsystems (3)
[email protected]
maintainerThe patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x a8682d500f691b6dfaa16ae1502d990aeb86e8be
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026012637-grope-geologic-e069@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From a8682d500f691b6dfaa16ae1502d990aeb86e8be Mon Sep 17 00:00:00 2001
From: "David Hildenbrand (Red Hat)" <[email protected]>
Date: Tue, 23 Dec 2025 22:40:36 +0100
Subject: [PATCH] mm/rmap: fix two comments related to huge_pmd_unshare()
PMD page table unsharing no longer touches the refcount of a PMD page table. Also, it is not about dropping the refcount of a "PMD page" but the "PMD page table".
Let's just simplify by saying that the PMD page table was unmapped, consequently also unmapping the folio that was mapped into this page.
This code should be deduplicated in the future.
mm/rmap.c +4 -16
@@ -2016,14 +2016,8 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,flush_tlb_range (vma, range.start, range.end);/* -* The ref count of the PMD page was -* dropped which is part of the way map -* counting is done for shared PMDs. -* Return 'true' here. When there is -* no other sharing, huge_pmd_unshare -* returns false and we will unmap the -* actual page and drop map count -* to zero. +* The PMD table was unmapped, +* consequently unmapping the folio. */ goto walk_done; }
@@ -2416,14 +2410,8 @@ static bool try_to_migrate_one(struct folio *folio, struct vm_area_struct *vma, range.start, range.end);/* -* The ref count of the PMD page was -* dropped which is part of the way map -* counting is done for shared PMDs. -* Return 'true' here. When there is -* no other sharing, huge_pmd_unshare -* returns false and we will unmap the -* actual page and drop map count -* to zero. +* The PMD table was unmapped, +* consequently unmapping the folio. */ page_vma_mapped_walk_done (&pvmw);break ;
Sasha Levin
maintainerPATCH 1/1 mm/rmap: fix two comments related to huge_pmd_unshare()
From: "David Hildenbrand (Red Hat)" <[email protected]>
[ Upstream commit a8682d500f691b6dfaa16ae1502d990aeb86e8be ]
PMD page table unsharing no longer touches the refcount of a PMD page table. Also, it is not about dropping the refcount of a "PMD page" but the "PMD page table".
Let's just simplify by saying that the PMD page table was unmapped, consequently also unmapping the folio that was mapped into this page.
This code should be deduplicated in the future.
--- mm/rmap.c | 20 ++++---------------- 1 file changed, 4 insertions(+), 16 deletions(-)
mm/rmap.c +4 -16
@@ -1574,14 +1574,8 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma,mmu_notifier_invalidate_range (mm, range.start, range.end);/* -* The ref count of the PMD page was -* dropped which is part of the way map -* counting is done for shared PMDs. -* Return 'true' here. When there is -* no other sharing, huge_pmd_unshare -* returns false and we will unmap the -* actual page and drop map count -* to zero. +* The PMD table was unmapped, +* consequently unmapping the folio. */ page_vma_mapped_walk_done (&pvmw);break ;
@@ -1965,14 +1959,8 @@ static bool try_to_migrate_one(struct folio *folio, struct vm_area_struct *vma, range.start, range.end);/* -* The ref count of the PMD page was -* dropped which is part of the way map -* counting is done for shared PMDs. -* Return 'true' here. When there is -* no other sharing, huge_pmd_unshare -* returns false and we will unmap the -* actual page and drop map count -* to zero. +* The PMD table was unmapped, +* consequently unmapping the folio. */ page_vma_mapped_walk_done (&pvmw);break ;
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