The patch titled
Subject: lib: dhry: fix sleeping allocations inside non-preemptable section
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
lib-dhry-fix-sleeping-allocations-inside-non-preemptable-section.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/lib-dhry-fix-sleeping-allocations-inside-non-preemptable-section.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: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Subject: lib: dhry: fix sleeping allocations inside non-preemptable section
Date: Wed, 5 Jul 2023 16:54:04 +0200
The Smatch static checker reports the following warnings:
lib/dhry_run.c:38 dhry_benchmark() warn: sleeping in atomic context
lib/dhry_run.c:43 dhry_benchmark() warn: sleeping in atomic context
Indeed, dhry() does sleeping allocations inside the non-preemptable
section delimited by get_cpu()/put_cpu().
Fix this by using atomic allocations instead.
Add error handling, as atomic these allocations may fail.
Link: https://lkml.kernel.org/r/bac6d517818a7cd8efe217c1ad649fffab9cc371.1688568764.git.geert+renesas@xxxxxxxxx
Fixes: 13684e966d46283e ("lib: dhry: fix unstable smp_processor_id(_) usage")
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Closes: https://lore.kernel.org/r/0469eb3a-02eb-4b41-b189-de20b931fa56@moroto.mountain
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/dhry_1.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
--- a/lib/dhry_1.c~lib-dhry-fix-sleeping-allocations-inside-non-preemptable-section
+++ a/lib/dhry_1.c
@@ -139,8 +139,15 @@ int dhry(int n)
/* Initializations */
- Next_Ptr_Glob = (Rec_Pointer)kzalloc(sizeof(Rec_Type), GFP_KERNEL);
- Ptr_Glob = (Rec_Pointer)kzalloc(sizeof(Rec_Type), GFP_KERNEL);
+ Next_Ptr_Glob = (Rec_Pointer)kzalloc(sizeof(Rec_Type), GFP_ATOMIC);
+ if (!Next_Ptr_Glob)
+ return -ENOMEM;
+
+ Ptr_Glob = (Rec_Pointer)kzalloc(sizeof(Rec_Type), GFP_ATOMIC);
+ if (!Ptr_Glob) {
+ kfree(Next_Ptr_Glob);
+ return -ENOMEM;
+ }
Ptr_Glob->Ptr_Comp = Next_Ptr_Glob;
Ptr_Glob->Discr = Ident_1;
_
Patches currently in -mm which might be from geert+renesas@xxxxxxxxx are
lib-dhry-fix-sleeping-allocations-inside-non-preemptable-section.patch
