lkml.org 
[lkml]   [2005]   [Mar]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH] APM: fix interrupts enabled in device_power_up
On Sat, 12 Mar 2005, J. Bruce Fields wrote:

> On APM resume this morning on my Thinkpad X31, I got a "spin_lock is
> already locked" error; see below. This doesn't happen on every resume,
> though it's happened before. The kernel is 2.6.11 plus a bunch of
> (hopefully unrelated...) NFS patches.
>
> Mar 12 07:07:31 puzzle kernel: PCI: Setting latency timer of device 0000:00:1f.5 to 64
> Mar 12 07:07:31 puzzle kernel: arch/i386/kernel/time.c:179: spin_lock(arch/i386/kernel/time.c:c0603c28) already locked by arch/i386/kernel/time.c/309
> Mar 12 07:07:31 puzzle kernel: arch/i386/kernel/time.c:316: spin_unlock(arch/i386/kernel/time.c:c0603c28) not locked

APM was calling device_power_down and device_power_up with interrupts
enabled, resulting in a few calls to get_cmos_time being done with
interrupts enabled (rtc_lock needs to be acquired with interrupts
disabled).

Signed-off-by: Zwane Mwaikambo <zwane@arm.linux.org.uk>

===== arch/i386/kernel/apm.c 1.72 vs edited =====
--- 1.72/arch/i386/kernel/apm.c 2005-01-20 22:02:11 -07:00
+++ edited/arch/i386/kernel/apm.c 2005-03-12 08:17:52 -07:00
@@ -1202,10 +1202,11 @@
}

device_suspend(PMSG_SUSPEND);
+ local_irq_disable();
device_power_down(PMSG_SUSPEND);

/* serialize with the timer interrupt */
- write_seqlock_irq(&xtime_lock);
+ write_seqlock(&xtime_lock);

/* protect against access to timer chip registers */
spin_lock(&i8253_lock);
@@ -1216,20 +1217,22 @@
* We'll undo any timer changes due to interrupts below.
*/
spin_unlock(&i8253_lock);
- write_sequnlock_irq(&xtime_lock);
+ write_sequnlock(&xtime_lock);
+ local_irq_enable();

save_processor_state();
err = set_system_power_state(APM_STATE_SUSPEND);
restore_processor_state();

- write_seqlock_irq(&xtime_lock);
+ local_irq_disable();
+ write_seqlock(&xtime_lock);
spin_lock(&i8253_lock);
reinit_timer();
set_time();
ignore_normal_resume = 1;

spin_unlock(&i8253_lock);
- write_sequnlock_irq(&xtime_lock);
+ write_sequnlock(&xtime_lock);

if (err == APM_NO_ERROR)
err = APM_SUCCESS;
@@ -1237,6 +1240,7 @@
apm_error("suspend", err);
err = (err == APM_SUCCESS) ? 0 : -EIO;
device_power_up();
+ local_irq_enable();
device_resume();
pm_send_all(PM_RESUME, (void *)0);
queue_event(APM_NORMAL_RESUME, NULL);
@@ -1255,17 +1259,22 @@
{
int err;

+ local_irq_disable();
device_power_down(PMSG_SUSPEND);
/* serialize with the timer interrupt */
- write_seqlock_irq(&xtime_lock);
+ write_seqlock(&xtime_lock);
/* If needed, notify drivers here */
get_time_diff();
- write_sequnlock_irq(&xtime_lock);
+ write_sequnlock(&xtime_lock);
+ local_irq_enable();

err = set_system_power_state(APM_STATE_STANDBY);
if ((err != APM_SUCCESS) && (err != APM_NO_ERROR))
apm_error("standby", err);
+
+ local_irq_disable();
device_power_up();
+ local_irq_enable();
}

static apm_event_t get_event(void)
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
\
 
 \ /
  Last update: 2005-03-22 14:11    [W:0.101 / U:0.316 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site