From eb019503569c8c701f1e9c70e848d99c6680839b Mon Sep 17 00:00:00 2001 From: Vegard Nossum Date: Sun, 10 Jul 2016 19:14:01 +0200 Subject: [PATCH 1/2] perf/x86: Fix bogus kernel printk, again This showed up as "6Failed to access..." here. Signed-off-by: Vegard Nossum Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Chen Yucong Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: 1b74dde7c47c ("x86/cpu: Convert printk(KERN_ ...) to pr_(...)") Link: http://lkml.kernel.org/r/1468170841-17045-1-git-send-email-vegard.nossum@oracle.com Signed-off-by: Ingo Molnar --- arch/x86/events/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 26ced536005a..91eac39625be 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -263,7 +263,7 @@ static bool check_hw_exists(void) msr_fail: pr_cont("Broken PMU hardware detected, using software events only.\n"); - pr_info("%sFailed to access perfctr msr (MSR %x is %Lx)\n", + printk("%sFailed to access perfctr msr (MSR %x is %Lx)\n", boot_cpu_has(X86_FEATURE_HYPERVISOR) ? KERN_INFO : KERN_ERR, reg, val_new); From 2c13ce8f6b2f6fd9ba2f9261b1939fc0f62d1307 Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Fri, 8 Jul 2016 01:39:11 +0300 Subject: [PATCH 2/2] posix_cpu_timer: Exit early when process has been reaped Variable "now" seems to be genuinely used unintialized if branch if (CPUCLOCK_PERTHREAD(timer->it_clock)) { is not taken and branch if (unlikely(sighand == NULL)) { is taken. In this case the process has been reaped and the timer is marked as disarmed anyway. So none of the postprocessing of the sample is required. Return right away. Signed-off-by: Alexey Dobriyan Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20160707223911.GA26483@p183.telecom.by Signed-off-by: Thomas Gleixner --- kernel/time/posix-cpu-timers.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c index 1cafba860b08..39008d78927a 100644 --- a/kernel/time/posix-cpu-timers.c +++ b/kernel/time/posix-cpu-timers.c @@ -777,6 +777,7 @@ static void posix_cpu_timer_get(struct k_itimer *timer, struct itimerspec *itp) timer->it.cpu.expires = 0; sample_to_timespec(timer->it_clock, timer->it.cpu.expires, &itp->it_value); + return; } else { cpu_timer_sample_group(timer->it_clock, p, &now); unlock_task_sighand(p, &flags);