linux-kernel - [tip: sched/urgent] sched/vtime: Work around an unitialized variable warning

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Wed, 15 Apr 2020 09:14:19 -0000
From:   "tip-bot2 for Borislav Petkov" <tip-bot2@...utronix.de>
To:     linux-tip-commits@...r.kernel.org
Cc:     Peter Zijlstra <peterz@...radead.org>,
        Borislav Petkov <bp@...e.de>, Ingo Molnar <mingo@...nel.org>,
        x86 <x86@...nel.org>, LKML <linux-kernel@...r.kernel.org>
Subject: [tip: sched/urgent] sched/vtime: Work around an unitialized variable warning

The following commit has been merged into the sched/urgent branch of tip:

Commit-ID:     e0d648f9d883ec1efab261af158d73aa30e9dd12
Gitweb:        https://git.kernel.org/tip/e0d648f9d883ec1efab261af158d73aa30e9dd12
Author:        Borislav Petkov <bp@...e.de>
AuthorDate:    Fri, 27 Mar 2020 22:43:34 +01:00
Committer:     Ingo Molnar <mingo@...nel.org>
CommitterDate: Wed, 15 Apr 2020 11:06:50 +02:00

sched/vtime: Work around an unitialized variable warning

Work around this warning:

  kernel/sched/cputime.c: In function ‘kcpustat_field’:
  kernel/sched/cputime.c:1007:6: warning: ‘val’ may be used uninitialized in this function [-Wmaybe-uninitialized]

because GCC can't see that val is used only when err is 0.

Acked-by: Peter Zijlstra <peterz@...radead.org>
Signed-off-by: Borislav Petkov <bp@...e.de>
Signed-off-by: Ingo Molnar <mingo@...nel.org>
Link: https://lore.kernel.org/r/20200327214334.GF8015@zn.tnic
---
 kernel/sched/cputime.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index dac9104..ff9435d 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -1003,12 +1003,12 @@ u64 kcpustat_field(struct kernel_cpustat *kcpustat,
 		   enum cpu_usage_stat usage, int cpu)
 {
 	u64 *cpustat = kcpustat->cpustat;
+	u64 val = cpustat[usage];
 	struct rq *rq;
-	u64 val;
 	int err;
 
 	if (!vtime_accounting_enabled_cpu(cpu))
-		return cpustat[usage];
+		return val;
 
 	rq = cpu_rq(cpu);