From dc6498128bb0a978a0be41e063cb26772e4abe17 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Wed, 10 Jan 2018 17:10:12 +1100 Subject: [PATCH] powerpc: Don't preempt_disable() in show_cpuinfo() commit 349524bc0da698ec77f2057cf4a4948eb6349265 upstream. This causes warnings from cpufreq mutex code. This is also rather unnecessary and ineffective. If we really want to prevent concurrent unplug, we could take the unplug read lock but I don't see this being critical. Fixes: cd77b5ce208c ("powerpc/powernv/cpufreq: Fix the frequency read by /proc/cpuinfo") Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman Acked-by: Michal Suchanek Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/setup-common.c | 11 ----------- 1 file changed, 11 deletions(-) diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c index 1362cd62b3fa5..d4c368b09415b 100644 --- a/arch/powerpc/kernel/setup-common.c +++ b/arch/powerpc/kernel/setup-common.c @@ -217,14 +217,6 @@ static int show_cpuinfo(struct seq_file *m, void *v) unsigned short maj; unsigned short min; - /* We only show online cpus: disable preempt (overzealous, I - * knew) to prevent cpu going down. */ - preempt_disable(); - if (!cpu_online(cpu_id)) { - preempt_enable(); - return 0; - } - #ifdef CONFIG_SMP pvr = per_cpu(cpu_pvr, cpu_id); #else @@ -329,9 +321,6 @@ static int show_cpuinfo(struct seq_file *m, void *v) #ifdef CONFIG_SMP seq_printf(m, "\n"); #endif - - preempt_enable(); - /* If this is the last cpu, print the summary */ if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids) show_cpuinfo_summary(m); -- 2.47.3