[PATCH 1/2] mmc: bcm2835: reset host on timeout

[Michal Suchánek]

On Wed, 14 Feb 2018 21:30:16 +0100 (CET)
Stefan Wahren <stefan.wahren at i2se.com> wrote:

> Hi Michal,
> 
> > Michal Suchánek <msuchanek at suse.de> hat am 14. Februar 2018 um
> > 20:24 geschrieben:
> > 
> > 
> > On Wed, 14 Feb 2018 17:49:31 +0100
> > Stefan Wahren <stefan.wahren at i2se.com> wrote:
> >   
> > > Hi Michal,
> > > 
> > > [add Phil]
> > > 
> > > Am 14.02.2018 um 17:13 schrieb Michal Suchánek:  
> > > > On Wed, 14 Feb 2018 16:36:49 +0100
> > > > Michal Suchánek <msuchanek at suse.de> wrote:
> > > >    
> > > >> On Wed, 14 Feb 2018 15:58:31 +0100
> > > >> Stefan Wahren <stefan.wahren at i2se.com> wrote:
> > > >>    
> > > >>> Hi Michal,
> > > >>>
> > > >>> Am 14.02.2018 um 15:38 schrieb Michal Suchanek:      
> > > >>>> The bcm2835 mmc host tends to lock up for unknown reason so
> > > >>>> reset it on timeout. The upper mmc block layer tries
> > > >>>> retransimitting with single blocks which tends to work out
> > > >>>> after a long wait.
> > > >>>>
> > > >>>> This is better than giving up and leaving the machine broken
> > > >>>> for no obvious reason.        
> > > >>> could you please provide more information about this issue
> > > >>> (affected hardware, kernel config, version, dmesg,
> > > >>> reproducible scenario)?   
> > > > It tends to reproduce when upgrading a few packages with zypper
> > > > and otherwise at random during system operation. It seems that
> > > > for my card it worsens with age to some degree so perhaps it
> > > > depends on the fragmentation of the internal card flash.
> > > >
> > > > Attaching dmesg and kernel config.    
> > > 
> > > do you noticed this issue before 4.15-rc4?  
> > 
> > I initially noticed it with 4.4 kernel with some backports to make
> > it bootable on RPi.  
> 
> this confuses me. Gerd and i ported this driver from downstream and
> finally it's got merged in 4.12. 
> 
> So do you mean that you backported the mainline version to 4.4 or the
> downstream version of 4.4?

I did not backport it but looking at the changelog it is backport of
the 4.12 driver. It does not look as the 4.15 driver though. Looks like
there was some reorganization of the bcm mmc since then.

> 
> On a quick look they seems identical, but they aren't.
> 
> > > 
> > > Could you please test with 4.15 final again?  
> >

I tried upgrading to the current master (4.16-rc3+) and the issue is
still reproducible although less frequent. I did full upgrade from the
install image which installs over 300 packages and the issue triggered
somewhere around 200th while before installing a half dozen packages
would usually trigger it.

 
> > Right, I can apply the patches on something more recent.
> >   
> > > 
> > > What kind of SD card (name) triggers the issue?  
> > 
> > Samsung EVO MB-MP16D  
> 
> Thanks
> 
> > 
> > Also see https://elinux.org/RPi_SD_cards#Which_SD_card.3F  
> 
> I'm very sceptical about this list. The card above is listed as OK
> and NOK. The experienced issues doesn't need to be direct related to
> the card (unproperly umounted, bad driver, ...).

Right, it just shows that this is not an isolated problem. Not all test
results are reliable, of course. Some include interesting details,
though.

Thanks

Michal
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: dmesg.4.16.txt
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20180304/a88acd5a/attachment-0001.txt>