Hi:
* Rafael J. Wysocki <rjw at sisk.pl> [2007-12-01 00:51:40 +0100]:
> On Saturday, 1 of December 2007, Rafael J. Wysocki wrote:
> > On Friday, 30 of November 2007, Jiri Slaby wrote:
> > > On 11/30/2007 11:15 PM, Jean Delvare wrote:
> > > > Hi Jiri,
> > >
> [--snip--]
> > > >
> > > > Should this change go to the stable tree(s) as well?
> > >
> > > Sorry, I have no idea. Rafael?
> >
> > Well, actually, having looked once again at the patch, I think that it's
> > slightly wrong. Namely, it looks like we just should drop all of the _FROZEN
> > actions from there.
> >
> > Fixed patch follows and I think it's also a candidate for -stable.
>
> Crap, I forgot to add the sign-off, so here it goes again:
>
> ---
> Subject: HWMON: coretemp, suspend fix
>
> It's not permitted to unregister a device after devices have been suspended.
> It causes deadlocks to appear on systems with coretemp hwmon loaded. To avoid
> this, we can make coretemp_cpu_callback() do nothing if the _FROZEN bit is set
> in action.
>
> Also, in other cases it's generally to late to unregister the coretemp device
> if the CPU is already dead, so it should be unregistered on CPU_DOWN_PREPARE.
>
> Signed-off-by: Rafael J. Wysocki <rjw at sisk.pl> (frozen fix)
> Cc: Mark M. Hoffman <mhoffman at lightlink.com>
> Cc: Jiri Slaby <jirislaby at gmail.com>
> Cc: Andrew Morton <akpm at linux-foundation.org>
> ---
>
> drivers/hwmon/coretemp.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
> Index: linux-2.6/drivers/hwmon/coretemp.c
> ===================================================================
> --- linux-2.6.orig/drivers/hwmon/coretemp.c
> +++ linux-2.6/drivers/hwmon/coretemp.c
> @@ -337,11 +337,10 @@ static int coretemp_cpu_callback(struct
>
> switch (action) {
> case CPU_ONLINE:
> - case CPU_ONLINE_FROZEN:
> + case CPU_DOWN_FAILED:
> coretemp_device_add(cpu);
> break;
> - case CPU_DEAD:
> - case CPU_DEAD_FROZEN:
> + case CPU_DOWN_PREPARE:
> coretemp_device_remove(cpu);
> break;
> }
Sorry for the delay, it took me some time to RTF code and convince
myself that nothing can tickle this driver's sysfs files after a
CPU_DOWN_PREPARE_FROZEN. As long as I didn't misread that...
Acked-by: Mark M. Hoffman <mhoffman at lightlink.com>
PS: while reading kernel/power/disk.c, I saw this...
335 static void power_down(void)
336 {
337 switch (hibernation_mode) {
338 case HIBERNATION_TEST:
339 case HIBERNATION_TESTPROC:
340 break;
341 case HIBERNATION_REBOOT:
342 kernel_restart(NULL);
343 break;
344 case HIBERNATION_PLATFORM:
345 hibernation_platform_enter();
346 case HIBERNATION_SHUTDOWN:
347 kernel_power_off();
348 break;
349 }
350 kernel_halt();
351 /*
352 * Valid image is on the disk, if we continue we risk serious data
353 * corruption after resume.
354 */
355 printk(KERN_CRIT "Please power me down manually\n");
356 while(1);
357 }
Shouldn't that be while(1) cpu_relax(); ?
Regards,
--
Mark M. Hoffman
mhoffman at lightlink.com
