Occasional mmc0 timeout on 2.6.25 master kernels

[C. Scott Ananian]

On Thu, May 1, 2008 at 10:52 PM, Denver Gingerich <denver at ossguy.com> wrote:
> When booting 2.6.25 master kernels (specifically seen on 20080501.2
>  and 20080501.3) from an SD card, the following error occurs every 5th
>  boot or so:
>
>  [ 3.512185] Waiting 2sec before mounting root device...
>  [ 5.574603] VFS: Cannot open root device "mmcblk0p1" or unknown-block(0,0)
>  [ 5.577210] Please append a correct "root=" boot option; here are the
>  available partitions:
>  ...
>  [ 5.747213] Kernel panic - not syncing: VFS: Unable to mount root fs
>  on unknown-block(0,0)
>  [13.597220] mmc0: Timeout waiting for hardware interrupt.
>
>  I have never encountered this error using 2.6.22-20071121.7 with over 50 boots.

Does increasing rootdelay help?  ie, is the problem that setting up SD
is now taking (say) 1.5-2.5 seconds instead of 1-2 seconds, and so
sometimes the SD card is not present after the 2 second rootdelay?
 --scott

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