* linux-next: build warning after merge of the percpu tree
@ 2017-06-21 5:20 Stephen Rothwell
2017-06-21 15:51 ` [PATCH 1/1] percpu: resolve err may not be initialized in pcpu_alloc Dennis Zhou
0 siblings, 1 reply; 3+ messages in thread
From: Stephen Rothwell @ 2017-06-21 5:20 UTC (permalink / raw)
To: Tejun Heo, Christoph Lameter, Ingo Molnar
Cc: Linux-Next Mailing List, Linux Kernel Mailing List, Dennis Zhou
Hi all,
After merging the percpu tree, today's linux-next build (arm
multi_v7_defconfig) produced this warning:
In file included from include/linux/kernel.h:13:0,
from include/linux/bitmap.h:9,
from mm/percpu.c:58:
mm/percpu.c: In function 'pcpu_alloc':
include/linux/printk.h:303:2: warning: 'err' may be used uninitialized in this function [-Wmaybe-uninitialized]
printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
^
mm/percpu.c:864:14: note: 'err' was declared here
const char *err;
^
I am not sure which commit introduced this, although the
if (is_atomic)
goto fail;
in pcpu_alloc() looks suspicious.
--
Cheers,
Stephen Rothwell
^ permalink raw reply [flat|nested] 3+ messages in thread* [PATCH 1/1] percpu: resolve err may not be initialized in pcpu_alloc
2017-06-21 5:20 linux-next: build warning after merge of the percpu tree Stephen Rothwell
@ 2017-06-21 15:51 ` Dennis Zhou
2017-06-21 16:02 ` Tejun Heo
0 siblings, 1 reply; 3+ messages in thread
From: Dennis Zhou @ 2017-06-21 15:51 UTC (permalink / raw)
To: Stephen Rothwell, Tejun Heo
Cc: Christoph Lameter, Ingo Molnar, Linux-Next Mailing List,
Linux Kernel Mailing List
>From 4a42ecc735cff0015cc73c3d87edede631f4b885 Mon Sep 17 00:00:00 2001
From: Dennis Zhou <dennisz@fb•com>
Date: Wed, 21 Jun 2017 08:07:15 -0700
Add error message to out of space failure for atomic allocations in
percpu allocation path to fix -Wmaybe-uninitialized.
Signed-off-by: Dennis Zhou <dennisz@fb•com>
Reported-by: Stephen Rothwell <sfr@canb•auug.org.au>
---
mm/percpu.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/mm/percpu.c b/mm/percpu.c
index a5bc363..bd4130a 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -956,8 +956,10 @@ static void __percpu *pcpu_alloc(size_t size, size_t align, bool reserved,
* tasks to create chunks simultaneously. Serialize and create iff
* there's still no empty chunk after grabbing the mutex.
*/
- if (is_atomic)
+ if (is_atomic) {
+ err = "atomic alloc failed, no space left";
goto fail;
+ }
if (list_empty(&pcpu_slot[pcpu_nr_slots - 1])) {
chunk = pcpu_create_chunk();
--
2.9.3
^ permalink raw reply related [flat|nested] 3+ messages in thread* Re: [PATCH 1/1] percpu: resolve err may not be initialized in pcpu_alloc
2017-06-21 15:51 ` [PATCH 1/1] percpu: resolve err may not be initialized in pcpu_alloc Dennis Zhou
@ 2017-06-21 16:02 ` Tejun Heo
0 siblings, 0 replies; 3+ messages in thread
From: Tejun Heo @ 2017-06-21 16:02 UTC (permalink / raw)
To: Dennis Zhou
Cc: Stephen Rothwell, Christoph Lameter, Ingo Molnar,
Linux-Next Mailing List, Linux Kernel Mailing List
On Wed, Jun 21, 2017 at 11:51:09AM -0400, Dennis Zhou wrote:
> From 4a42ecc735cff0015cc73c3d87edede631f4b885 Mon Sep 17 00:00:00 2001
> From: Dennis Zhou <dennisz@fb•com>
> Date: Wed, 21 Jun 2017 08:07:15 -0700
>
> Add error message to out of space failure for atomic allocations in
> percpu allocation path to fix -Wmaybe-uninitialized.
>
> Signed-off-by: Dennis Zhou <dennisz@fb•com>
> Reported-by: Stephen Rothwell <sfr@canb•auug.org.au>
Applied to percpu/for-4.13.
Thanks.
--
tejun
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2017-06-21 16:33 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2017-06-21 5:20 linux-next: build warning after merge of the percpu tree Stephen Rothwell
2017-06-21 15:51 ` [PATCH 1/1] percpu: resolve err may not be initialized in pcpu_alloc Dennis Zhou
2017-06-21 16:02 ` Tejun Heo
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox