lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

rtc-cmos: avoid spurious irqs

Browse Source 
This fixes kernel http://bugzilla.kernel.org/show_bug.cgi?id=11112 (bogus
RTC update IRQs reported) for rtc-cmos, in two ways:

  - When HPET is stealing the IRQs, use the first IRQ to grab
    the seconds counter which will be monitored (instead of
    using whatever was previously in that memory);

  - In sane IRQ handling modes, scrub out old IRQ status before
    enabling IRQs.

That latter is done by tightening up IRQ handling for rtc-cmos everywhere,
also ensuring that when HPET is used it's the only thing triggering IRQ
reports to userspace; net object shrink.

Also fix a bogus HPET message related to its RTC emulation.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Report-by: W Unruh <unruh@physics.ubc.ca>
Cc: Andrew Victor <avictor.za@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
David Brownell
2008-07-23 21:30:47 -07:00
committed by Linus Torvalds
parent 449321b39f
commit 7e2a31da85
2 changed files with 70 additions and 80 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
arch/x86/kernel/hpet.c
View File

@ -468,7 +468,7 @@ void hpet_disable(void)
#define RTC_NUM_INTS 1
static unsigned long hpet_rtc_flags;
static unsigned long hpet_prev_update_sec;
static int hpet_prev_update_sec;
static struct rtc_time hpet_alarm_time;
static unsigned long hpet_pie_count;
static unsigned long hpet_t1_cmp;
@ -575,6 +575,9 @@ int hpet_set_rtc_irq_bit(unsigned long bit_mask)
hpet_rtc_flags |= bit_mask;
if ((bit_mask & RTC_UIE) && !(oldbits & RTC_UIE))
hpet_prev_update_sec = -1;
if (!oldbits)
hpet_rtc_timer_init();
@ -652,7 +655,7 @@ static void hpet_rtc_timer_reinit(void)
if (hpet_rtc_flags & RTC_PIE)
hpet_pie_count += lost_ints;
if (printk_ratelimit())
printk(KERN_WARNING "rtc: lost %d interrupts\n",
printk(KERN_WARNING "hpet1: lost %d rtc interrupts\n",
lost_ints);
}
}
@ -670,7 +673,8 @@ irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id)
if (hpet_rtc_flags & RTC_UIE &&
curr_time.tm_sec != hpet_prev_update_sec) {
rtc_int_flag = RTC_UF;
if (hpet_prev_update_sec >= 0)
rtc_int_flag = RTC_UF;
hpet_prev_update_sec = curr_time.tm_sec;
}