Re: MMC/SD Root filesystem suspend/resume problems

[Richard Purdie <rpurdie@rpsys.net>]

On Thu, 2007-07-19 at 16:57 +0100, Richard Purdie wrote:
> Lots of Linux handhelds use MMC/SD devices as the root file system. This
> has worked quite reliably for many kernel versions. In 2.6.22, it seems
> that if you suspend such a system then resume it, the device locks up.
> Trying to execute anything on the filesystem results in a "Permission
> Denied" message. I did see a message from the MMC subsystem saying it
> had redetected the card. There are also messages on the console like
> "MMC: killing requests for dead queue" each time you suspend/resume.
> 
> I'm away from my serial cables at the moment but I may be able to
> provide more debug when I have them over the weekend. Have you any ideas
> on why this is breaking?
> 
> For reference, I've reproduced the problem with both the PXA host driver
> and different driver not merged into mainline (ASIC3).

Just to follow up, if I boot with a rootfs from elsewhere and mount the
mmc card then suspend/resume, it corrupts the data on the card too so it
looks like some general suspend/resume problem on mounted filesystems.

Richard