On Thursday, December 09, 2010, Takashi Iwai wrote: > At Thu, 9 Dec 2010 01:53:03 +0000, > Chris Ball wrote: > > > > Hi Takashi, > > > > On Wed, Dec 08, 2010 at 04:23:59PM +0100, Takashi Iwai wrote: > > > The commit 4c2ef25fe0b847d2ae818f74758ddb0be1c27d8e > > > mmc: fix all hangs related to mmc/sd card insert/removal during > > > suspend/resume > > > introduced a bug where the device probing no longer works after > > > hibernation. This was because the pm notifier expects > > > PM_POST_HIBERNATION call while the system sends PM_POST_RESTORE > > > instead, thus disable_rescan is kept as 1. > > > > > > Cc: <[email protected]> > > > Signed-off-by: Takashi Iwai <[email protected]> > > > --- > > > drivers/mmc/core/core.c | 2 +- > > > 1 files changed, 1 insertions(+), 1 deletions(-) > > > > > > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c > > > index 31ae07a..30094f6 100644 > > > --- a/drivers/mmc/core/core.c > > > +++ b/drivers/mmc/core/core.c > > > @@ -1772,7 +1772,7 @@ int mmc_pm_notify(struct notifier_block > > > *notify_block, > > > break; > > > > > > case PM_POST_SUSPEND: > > > - case PM_POST_HIBERNATION: > > > + case PM_POST_RESTORE: > > > > > > spin_lock_irqsave(&host->lock, flags); > > > host->rescan_disable = 0; > > > > Thanks very much for tracking this down! The code suggests that > > POST_RESTORE is only emitted on a *failed* hibernation restore -- > > from include/linux/notifier.h: > > > > /* Hibernation and suspend events */ > > #define PM_POST_HIBERNATION 0x0002 /* Hibernation finished */ > > #define PM_POST_SUSPEND 0x0004 /* Suspend finished */ > > #define PM_POST_RESTORE 0x0006 /* Restore failed */ > > > > So, this all suggests that we want to add the POST_RESTORE case but > > also want to keep the POST_HIBERNATION case. Do you agree? Was the > > case you saw of failed probe after hibernation a failed restore from > > hibernation image? > > Right, I took a look at Documentation/pm/notifiers.txt, and it's > clearly written that PM_POST_RESTORE is only for the error case. But > S4 resume succeeded actually on my machine, so it took time to spot > out the culprit. > > Looking at the code in kernel/power/, this might be the case of > user-space suspend. hibernate.c seems returning PM_POST_HIBERNATION > while user.c returns PM_POST_RESTORE after image restoration, and I > guess it's a bug of user.c. > > The untested patch is below (sorry I have no corresponding machine > at my home.) Rafael, Pavel, could you check this? > > > thanks, > > Takashi > > === > From 915fda609e02b02e4fc6b944e4432ea1d964adc5 Mon Sep 17 00:00:00 2001 > From: Takashi Iwai <[email protected]> > Date: Thu, 9 Dec 2010 08:09:21 +0100 > Subject: [PATCH] PM: Fix PM_POST_* notification with user-space suspend > > The user-space hibernation sends a wrong notification after the image > restoration because of thinko for the file flag check. RDONLY > corresponds to hibernation and WRONLY to restoration, confusingly.
The patch is correct. I'm taking it to my tree. Thanks, Rafael > Signed-off-by: Takashi Iwai <[email protected]> > --- > kernel/power/user.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/kernel/power/user.c b/kernel/power/user.c > index e819e17..11d92b2 100644 > --- a/kernel/power/user.c > +++ b/kernel/power/user.c > @@ -137,7 +137,7 @@ static int snapshot_release(struct inode *inode, struct > file *filp) > free_all_swap_pages(data->swap); > if (data->frozen) > thaw_processes(); > - pm_notifier_call_chain(data->mode == O_WRONLY ? > + pm_notifier_call_chain(data->mode == O_RDONLY ? > PM_POST_HIBERNATION : PM_POST_RESTORE); > atomic_inc(&snapshot_device_available); > > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
