+ maple_tree-not-necessary-to-check-index-last-again.patch added to mm-unstable branch

+ maple_tree-not-necessary-to-check-index-last-again.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: maple_tree: not necessary to check index/last again
has been added to the -mm mm-unstable branch.  Its filename is
     maple_tree-not-necessary-to-check-index-last-again.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/maple_tree-not-necessary-to-check-index-last-again.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days

------------------------------------------------------
From: Wei Yang <richard.weiyang@gmail.com>
Subject: maple_tree: not necessary to check index/last again
Date: Tue, 15 Oct 2024 23:39:08 +0000

Patch series "fix mas_new_root()".

When overwriting the whole range with NULL, current behavior is not correct.


This patch (of 2):

Before calling mas_new_root(), the range has been checked.

Link: https://lkml.kernel.org/r/20241015233909.23592-1-richard.weiyang@gmail.com
Link: https://lkml.kernel.org/r/20241015233909.23592-2-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/maple_tree.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/lib/maple_tree.c~maple_tree-not-necessary-to-check-index-last-again
+++ a/lib/maple_tree.c
@@ -3670,7 +3670,7 @@ static inline void mas_new_root(struct m
 	void __rcu **slots;
 	unsigned long *pivots;
 
-	if (!entry && !mas->index && mas->last == ULONG_MAX) {
+	if (!entry) {
 		mas->depth = 0;
 		mas_set_height(mas);
 		rcu_assign_pointer(mas->tree->ma_root, entry);
_

Patches currently in -mm which might be from richard.weiyang@gmail.com are

maple_tree-i-is-always-less-than-or-equal-to-mas_end.patch
maple_tree-goto-complete-directly-on-a-pivot-of-0.patch
maple_tree-remove-maple_big_nodeparent.patch
maple_tree-memset-maple_big_node-as-a-whole.patch
maple_tree-root-node-could-be-handled-by-p_slot-too.patch
maple_tree-clear-request_count-for-new-allocated-one.patch
maple_tree-total-is-not-changed-for-nomem_one-case.patch
maple_tree-simplify-mas_push_node.patch
maple_tree-not-necessary-to-check-index-last-again.patch
maple_tree-one-single-entry-couldnt-represent-the-whole-range.patch

+ maple_tree-not-necessary-to-check-index-last-again.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: maple_tree: not necessary to check index/last again
has been added to the -mm mm-unstable branch.  Its filename is
     maple_tree-not-necessary-to-check-index-last-again.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/maple_tree-not-necessary-to-check-index-last-again.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Before you just go and hit "reply", please:
   a) Consider who else should be cc'ed
   b) Prefer to cc a suitable mailing list as well
   c) Ideally: find the original patch on the mailing list and do a
      reply-to-all to that, adding suitable additional cc's

*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days

------------------------------------------------------
From: Wei Yang <richard.weiyang@gmail.com>
Subject: maple_tree: not necessary to check index/last again
Date: Thu, 31 Oct 2024 23:16:25 +0000

Before calling mas_new_root(), the range has been checked.

Link: https://lkml.kernel.org/r/20241031231627.14316-4-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Liam R. Howlett <Liam.Howlett@Oracle.com>
Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/maple_tree.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/lib/maple_tree.c~maple_tree-not-necessary-to-check-index-last-again
+++ a/lib/maple_tree.c
@@ -3670,7 +3670,9 @@ static inline void mas_new_root(struct m
 	void __rcu **slots;
 	unsigned long *pivots;
 
-	if (!entry && !mas->index && mas->last == ULONG_MAX) {
+	WARN_ON_ONCE(mas->index || mas->last != ULONG_MAX);
+
+	if (!entry) {
 		mas->depth = 0;
 		mas_set_height(mas);
 		rcu_assign_pointer(mas->tree->ma_root, entry);
_

Patches currently in -mm which might be from richard.weiyang@gmail.com are

mm-mlock-set-the-correct-prev-on-failure.patch
maple_tree-i-is-always-less-than-or-equal-to-mas_end.patch
maple_tree-goto-complete-directly-on-a-pivot-of-0.patch
maple_tree-remove-maple_big_nodeparent.patch
maple_tree-memset-maple_big_node-as-a-whole.patch
maple_tree-root-node-could-be-handled-by-p_slot-too.patch
maple_tree-clear-request_count-for-new-allocated-one.patch
maple_tree-total-is-not-changed-for-nomem_one-case.patch
maple_tree-simplify-mas_push_node.patch
maple_tree-calculate-new_end-when-needed.patch
maple_tree-remove-sanity-check-from-mas_wr_slot_store.patch
mm-vma-the-pgoff-is-correct-if-can_merge_right.patch
maple_tree-print-empty-for-an-empty-tree-on-mt_dump.patch
maple_tree-the-return-value-of-mas_root_expand-is-not-used.patch
maple_tree-not-necessary-to-check-index-last-again.patch
maple_tree-refine-mas_store_root-on-storing-null.patch
maple_tree-add-a-test-checking-storing-null.patch