On Sat, Mar 12, 2005 at 09:25:13AM -0700, Zwane Mwaikambo wrote:
> On Sat, 12 Mar 2005, George Anzinger wrote:
>
> > And more... That this occures implies we are attempting to update the cmos
> > clock on resume seems wrong. One would presume that the time is wrong at
> > this
> > time and we are about to save that wrong time. Possibly the APM code should
> > change time_status to STA_UNSYNC on the way into the sleep (or what ever it
> > is
> > called). Who should we ping with this?
>
> timer_resume, which appears to be the problem, wants to calculate amount
> of time was spent suspended, also your unconditional irq enable in
> get_cmos_time breaks the atomicity of device_power_up and would deadlock
> in sections of code which call get_time_diff() with xtime_lock held. I
> sent a patch subject "APM: fix interrupts enabled in device_power_up"
> which should address this.
>
How about this patch? Also fixes one other use of rtc_lock in acpi/sleep/proc.c
Thanks,
Venki
rtc_lock is held during timer interrupts. So, we should block interrupts
while holding it.
Signed-off-by: Venkatesh Pallipadi <[EMAIL PROTECTED]>
--- linux-2.6.10/arch/i386/kernel/time.c.org 2005-03-12 10:38:23.000000000
-0800
+++ linux-2.6.10/arch/i386/kernel/time.c 2005-03-12 10:40:26.000000000
-0800
@@ -305,15 +305,16 @@ irqreturn_t timer_interrupt(int irq, voi
unsigned long get_cmos_time(void)
{
unsigned long retval;
+ unsigned long flags;
- spin_lock(&rtc_lock);
+ spin_lock_irqsave(&rtc_lock, flags);
if (efi_enabled)
retval = efi_get_time();
else
retval = mach_get_cmos_time();
- spin_unlock(&rtc_lock);
+ spin_unlock_restore(&rtc_lock, flags);
return retval;
}
--- linux-2.6.10/drivers/acpi/sleep/proc.c.org 2005-03-12 10:50:40.000000000
-0800
+++ linux-2.6.10/drivers/acpi/sleep/proc.c 2005-03-12 10:53:08.000000000
-0800
@@ -84,10 +84,11 @@ static int acpi_system_alarm_seq_show(st
u32 sec, min, hr;
u32 day, mo, yr;
unsigned char rtc_control = 0;
+ unsigned long flags;
ACPI_FUNCTION_TRACE("acpi_system_alarm_seq_show");
- spin_lock(&rtc_lock);
+ spin_lock_irqsave(&rtc_lock, flags);
sec = CMOS_READ(RTC_SECONDS_ALARM);
min = CMOS_READ(RTC_MINUTES_ALARM);
@@ -109,7 +110,7 @@ static int acpi_system_alarm_seq_show(st
else
yr = CMOS_READ(RTC_YEAR);
- spin_unlock(&rtc_lock);
+ spin_unlock_restore(&rtc_lock, flags);
if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
BCD_TO_BIN(sec);
-
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