[PATCH] common: filetype: do not redetect MBR-type devices as a FAT-type

[Sascha Hauer]

On Tue, Nov 10, 2015 at 09:04:23AM +0100, Sascha Hauer wrote:
> On Mon, Nov 09, 2015 at 06:49:53PM +0000, Trent Piepho wrote:
> > On Mon, 2015-11-09 at 13:32 +0300, Peter Mamonov wrote:
> > > Deleted pieces of code detect MBR-containig device as a FAT-type device,
> > > if it's first partition contains a FAT filesystem. This behaviour enabled one
> > > to mount the FAT FS which is either directly on the device (disk0) or on
> > > the first partition (disk0.0) using the same command:
> > >     mount /dev/disk0 /fat
> > > However, the desired behaviour can be reached with a:
> > >     mount /dev/disk0 /fat || mount /dev/disk0.0 /fat || echo "Mounting failed"
> > 
> > The in flash env for omap is found by mounting a FAT filesystem and
> > reading an env file from it.  The code that does this uses the disk as
> > the device, rather than the partition.  Which I thought was odd and
> > wondered why/if that worked correctly....
> > 
> > Anyway, this change would break that code.  I suspect than instead of
> > coding the disk0 || disk0.0 method it could just mount disk0.0.  Because
> > the code does this (edited):
> > 
> > partname = asprintf("/dev/%s.0", diskdev);
> > ret = stat(partname, &s);
> > if (ret) {
> >   pr_err("Failed to load environment: no device '%s'\n", diskdev);
> >   return 0;
> > }
> > ret = mount(diskdev, "fat", "/boot", NULL);
> 
> This is really odd. The code first tests if the partition exists and
> tries to mount the whole disk afterwards. git blame points to:
> 
> commit be322768f04603df371c9c1f08b9621690dd74c6
> Author: Sascha Hauer <s.hauer at pengutronix.de>
> Date:   Sat Aug 24 12:48:50 2013 +0200
> 
>     ARM: omap: Allow to set mmc devname used for booting
> 
> I think what we should do here is in the following patch. With this
> Trents patch can be applied as-is. Thanks for noting, Peter.

Sorry, I mixed you two up. I mean: With this Peters patch can be
applied as-is. Thanks for noting, Trent.

Sascha

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