x86: avoid theoretical spurious NMI backtraces with CONFIG_CPUMASK_OFFSTACK=y

In theory (though not shown in practice) alloc_cpumask_var() doesn't zero
memory, so CPUs might print an "NMI backtrace for cpu %d" once on boot.

(Bug introduced in fcef8576d8).

[ Impact: avoid theoretical syslog noise in rare configs ]

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <alpine.DEB.2.00.0904202113520.10097@gandalf.stny.rr.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Rusty Russell 2009-04-21 16:03:41 +09:30 committed by Ingo Molnar
parent 2f537a9f8e
commit fcc5c4a2fe

View file

@ -138,7 +138,7 @@ int __init check_nmi_watchdog(void)
if (!prev_nmi_count)
goto error;
alloc_cpumask_var(&backtrace_mask, GFP_KERNEL);
alloc_cpumask_var(&backtrace_mask, GFP_KERNEL|__GFP_ZERO);
printk(KERN_INFO "Testing NMI watchdog ... ");
#ifdef CONFIG_SMP