Re: [PATCH] mmc: core: Prevent too long response times for suspend

[Ulf Hansson <ulf.hansson@stericsson.com>]

> 
> Why would there be pending requests while host is suspending? Is the
> kernel framework not handling sync before going to suspend? However, the
> mmc_blk_suspend() would be called before the host driver suspends (as all
> the driver suspend routines are serialized) which means it stops block
> layer to queue more I/O requests well before the host driver start
> suspend. Does this sequence break in your case?

I have observed this issue for different cases (one case was logging to 
eMMC). The idea is simply that we would like to be sure that we do not 
wait "forever", no matter if the "upper layers" misbehaved in the 
suspend sequence.

> 
> Your concern seems to be valid for SDIO case, but again the function
> driver must be intelligent enough to return -EBUSY as it knows that it had
> posted a request to MMC.
> 

For SDIO, should we really assume that function driver has implemented a 
suspend function and moreover that it actually always behaves as we expect?

Br
Ulf Hansson