The patch titled
Subject: mm: add RCU annotation to pte_offset_map(_lock)
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-add-rcu-annotation-to-pte_offset_map_lock.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-add-rcu-annotation-to-pte_offset_map_lock.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Petr Malat <oss@xxxxxxxxx>
Subject: mm: add RCU annotation to pte_offset_map(_lock)
Date: Tue, 10 Dec 2024 01:06:04 +0100
RCU lock is taken by ___pte_offset_map() unless it returns NULL. Add this
information to its inline callers to avoid sparse warning about context
imbalance in pte_unmap().
Link: https://lkml.kernel.org/r/20241210000604.700710-1-oss@xxxxxxxxx
Signed-off-by: Petr Malat <oss@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/mm.h | 13 +++++++++++--
mm/pgtable-generic.c | 2 +-
2 files changed, 12 insertions(+), 3 deletions(-)
--- a/include/linux/mm.h~mm-add-rcu-annotation-to-pte_offset_map_lock
+++ a/include/linux/mm.h
@@ -3011,7 +3011,15 @@ static inline void pagetable_pte_dtor(st
lruvec_stat_sub_folio(folio, NR_PAGETABLE);
}
-pte_t *__pte_offset_map(pmd_t *pmd, unsigned long addr, pmd_t *pmdvalp);
+pte_t *___pte_offset_map(pmd_t *pmd, unsigned long addr, pmd_t *pmdvalp);
+static inline pte_t *__pte_offset_map(pmd_t *pmd, unsigned long addr,
+ pmd_t *pmdvalp)
+{
+ pte_t *pte;
+
+ __cond_lock(RCU, pte = ___pte_offset_map(pmd, addr, pmdvalp));
+ return pte;
+}
static inline pte_t *pte_offset_map(pmd_t *pmd, unsigned long addr)
{
return __pte_offset_map(pmd, addr, NULL);
@@ -3024,7 +3032,8 @@ static inline pte_t *pte_offset_map_lock
{
pte_t *pte;
- __cond_lock(*ptlp, pte = __pte_offset_map_lock(mm, pmd, addr, ptlp));
+ __cond_lock(RCU, __cond_lock(*ptlp,
+ pte = __pte_offset_map_lock(mm, pmd, addr, ptlp)));
return pte;
}
--- a/mm/pgtable-generic.c~mm-add-rcu-annotation-to-pte_offset_map_lock
+++ a/mm/pgtable-generic.c
@@ -279,7 +279,7 @@ static unsigned long pmdp_get_lockless_s
static void pmdp_get_lockless_end(unsigned long irqflags) { }
#endif
-pte_t *__pte_offset_map(pmd_t *pmd, unsigned long addr, pmd_t *pmdvalp)
+pte_t *___pte_offset_map(pmd_t *pmd, unsigned long addr, pmd_t *pmdvalp)
{
unsigned long irqflags;
pmd_t pmdval;
_
Patches currently in -mm which might be from oss@xxxxxxxxx are
mm-add-rcu-annotation-to-pte_offset_map_lock.patch
