The patch titled
x86_64: fix last_tsc calculation of PM timer
has been added to the -mm tree. Its filename is
x86_64-fix-last_tsc-calculation-of-pm-timer.patch
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
------------------------------------------------------
Subject: x86_64: fix last_tsc calculation of PM timer
From: "Jan Beulich" <jbeulich@xxxxxxxxxx>
The PM timer code updates vxtime.last_tsc, but this update was done
incorrectly in two ways:
- offset_delay being in microseconds requires multiplying with cpu_mhz
rather than cpu_khz
- the multiplication of offset_delay and cpu_khz (both being 32-bit
values) on most current CPUs would overflow (observed value of the
delay was approximately 4000us, yielding an overflow for frequencies
starting a little above 1GHz)
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>
Signed-off-by: Andi Kleen <ak@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---
arch/x86_64/kernel/pmtimer.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff -puN arch/x86_64/kernel/pmtimer.c~x86_64-fix-last_tsc-calculation-of-pm-timer arch/x86_64/kernel/pmtimer.c
--- devel/arch/x86_64/kernel/pmtimer.c~x86_64-fix-last_tsc-calculation-of-pm-timer 2006-05-29 14:16:21.000000000 -0700
+++ devel-akpm/arch/x86_64/kernel/pmtimer.c 2006-05-29 14:16:21.000000000 -0700
@@ -68,7 +68,7 @@ int pmtimer_mark_offset(void)
offset_delay = delta % (USEC_PER_SEC / HZ);
rdtscll(tsc);
- vxtime.last_tsc = tsc - offset_delay * cpu_khz;
+ vxtime.last_tsc = tsc - offset_delay * (u64)cpu_khz / 1000;
/* don't calculate delay for first run,
or if we've got less then a tick */
_
Patches currently in -mm which might be from jbeulich@xxxxxxxxxx are
i386-apic=-command-line-option-should-always-be.patch
x86_64-fix-last_tsc-calculation-of-pm-timer.patch
dprintk-adjustments-to-cpufreq-nforce2.patch
dprintk-adjustments-to-cpufreq-speedstep-centrino.patch
cpufreq-dprintk-adjustments.patch
fix-recovery-path-from-errors-during-pcie_init.patch
mpt_interrupt-should-return-irq_none-when.patch
x86_64-reliable-stack-trace-support-i386-fix.patch
fix-x86-microcode-driver-handling-of-multiple-matching.patch
adjust-handle_irr_event-return-type.patch
-
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