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.
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>
---
Alternatively, memory (de)allocation could be spin off into their own
functions, and called outside the non-preemptable section. But that
would be more intrusive.
---
lib/dhry_1.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/lib/dhry_1.c b/lib/dhry_1.c
index 83247106824cc7f4..08edbbb19f573ff7 100644
--- a/lib/dhry_1.c
+++ b/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;
--
2.34.1
