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    SubjectRe: [PATCH] clean up FIXME in do_timer_interrupt-lock fix
    George Anzinger <george@mvista.com> wrote:
    >
    > Did you pick this up? First sent on 3-11.

    I did, although now looking at it I have issues.

    > I was not happy with the locking on this. Two changes:
    > 1) Turn off irq while setting the clock.
    > 2) Call the timer code only through the timer interface
    > (set a short timer to do it from the ntp call).

    I would consider this to be an inadequate description :(

    > Signed-off-by: George Anzinger <george@mvista.com>
    >
    > time.c | 6 +++---
    > 1 files changed, 3 insertions(+), 3 deletions(-)
    >
    > Index: linux-2.6.12-rc/arch/i386/kernel/time.c
    > ===================================================================
    > --- linux-2.6.12-rc.orig/arch/i386/kernel/time.c
    > +++ linux-2.6.12-rc/arch/i386/kernel/time.c
    > @@ -176,12 +176,12 @@ static int set_rtc_mmss(unsigned long no
    > int retval;
    >
    > /* gets recalled with irq locally disabled */
    > - spin_lock(&rtc_lock);
    > + spin_lock_irq(&rtc_lock);
    > if (efi_enabled)
    > retval = efi_set_rtc_mmss(nowtime);
    > else
    > retval = mach_set_rtc_mmss(nowtime);
    > - spin_unlock(&rtc_lock);
    > + spin_unlock_irq(&rtc_lock);
    >
    > return retval;
    > }

    If the comment is correct, and this code is called with local irq's
    disabled then this patch should be using spin_lock_irqsave()

    > @@ -338,7 +338,7 @@ static void sync_cmos_clock(unsigned lon
    > }
    > void notify_arch_cmos_timer(void)
    > {
    > - sync_cmos_clock(0);
    > + mod_timer(&sync_cmos_timer, jiffies + 1);
    > }
    > static long clock_cmos_diff, sleep_start;
    >

    Your description says what this does, but it doesn't way why it was done?
    -
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