The patch titled
Subject: maple_tree: reduce stack usage with gcc-9 and earlier
has been added to the -mm mm-unstable branch. Its filename is
maple_tree-reduce-stack-usage-with-gcc-9-and-earlier.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/maple_tree-reduce-stack-usage-with-gcc-9-and-earlier.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Arnd Bergmann <arnd@xxxxxxxx>
Subject: maple_tree: reduce stack usage with gcc-9 and earlier
Date: Tue, 14 Feb 2023 11:30:24 +0100
gcc-10 changed the way inlining works to be less aggressive, but older
versions run into an oversized stack frame warning whenever
CONFIG_KASAN_STACK is enabled, as that forces variables from inlined
callees to be non-overlapping:
lib/maple_tree.c: In function 'mas_wr_bnode':
lib/maple_tree.c:4320:1: error: the frame size of 1424 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
Change the annotations on mas_store_b_node() and mas_commit_b_node()
to explicitly forbid inlining in this configuration, which is
the same behavior that newer versions already have.
Link: https://lkml.kernel.org/r/20230214103030.1051950-1-arnd@xxxxxxxxxx
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andrey Konovalov <andreyknvl@xxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Cc: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Cc: Vernon Yang <vernon2gm@xxxxxxxxx>
Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/lib/maple_tree.c~maple_tree-reduce-stack-usage-with-gcc-9-and-earlier
+++ a/lib/maple_tree.c
@@ -146,6 +146,13 @@ struct maple_subtree_state {
struct maple_big_node *bn;
};
+#ifdef CONFIG_KASAN_STACK
+/* Prevent mas_wr_bnode() from exceeding the stack frame limit */
+#define noinline_for_kasan noinline_for_stack
+#else
+#define noinline_for_kasan inline
+#endif
+
/* Functions */
static inline struct maple_node *mt_alloc_one(gfp_t gfp)
{
@@ -2107,7 +2114,7 @@ static inline void mas_bulk_rebalance(st
*
* Return: The actual end of the data stored in @b_node
*/
-static inline void mas_store_b_node(struct ma_wr_state *wr_mas,
+static noinline_for_kasan void mas_store_b_node(struct ma_wr_state *wr_mas,
struct maple_big_node *b_node, unsigned char offset_end)
{
unsigned char slot;
@@ -3579,7 +3586,7 @@ static inline bool mas_reuse_node(struct
* @b_node: The maple big node
* @end: The end of the data.
*/
-static inline int mas_commit_b_node(struct ma_wr_state *wr_mas,
+static noinline_for_kasan int mas_commit_b_node(struct ma_wr_state *wr_mas,
struct maple_big_node *b_node, unsigned char end)
{
struct maple_node *node;
_
Patches currently in -mm which might be from arnd@xxxxxxxx are
maple_tree-reduce-stack-usage-with-gcc-9-and-earlier.patch
