From: Tim Mann Date: Mon, 14 Nov 2005 00:06:54 +0000 (-0800) Subject: [PATCH] x86: fix cpu_khz with clock=pit X-Git-Tag: firefly_0821_release~40072 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=7feacd53347c04aee789ba5d632eda0c3fc421c4;p=firefly-linux-kernel-4.4.55.git [PATCH] x86: fix cpu_khz with clock=pit Fix http://bugzilla.kernel.org/show_bug.cgi?id=5546 The cpu_khz global is not initialized and remains 0 if you boot with clock=pit, even if the processor does have a TSC. This may have bad ramifications since the variable is used in various places scattered around the kernel, though I didn't check them all to see if they can tolerate cpu_khz = 0. You can observe the problem by doing "cat /proc/cpuinfo"; the cpu MHz line says 0.000. The fix is trivial; call init_cpu_khz() from init_pit(), just as it's called from the timers/timer_foo.c:init_foo() for other values of foo. Cc: john stultz Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/arch/i386/kernel/timers/timer_pit.c b/arch/i386/kernel/timers/timer_pit.c index e42e46d35159..b9b6bd56b9ba 100644 --- a/arch/i386/kernel/timers/timer_pit.c +++ b/arch/i386/kernel/timers/timer_pit.c @@ -25,8 +25,9 @@ static int __init init_pit(char* override) { /* check clock override */ if (override[0] && strncmp(override,"pit",3)) - printk(KERN_ERR "Warning: clock= override failed. Defaulting to PIT\n"); - + printk(KERN_ERR "Warning: clock= override failed. Defaulting " + "to PIT\n"); + init_cpu_khz(); count_p = LATCH; return 0; }