On Thu, Sep 24, 2009 at 05:32:37PM +0200, Maurus Cuelenaere wrote:

Hi,

I'm currently experiencing an SDHCI bug in 2.6.31 and linux-next, which 
didn't
seem to appear in 2.6.31-rc8.

This is on a new S3C6410 platform (SmartQ 7, see [1]) and it seems to be
consistently happening right after displaying "Loading hardware drivers" (in
user-space; Ubuntu-based).

The relevant kernel log lines are:

blk: request botched
kernel BUG at drivers/mmc/host/sdhci.c:298!

Having a look at the code in mainline, this is being triggered in 
sdhci_write_block_pio(), by the following code:

296     while (blksize) {
297             if (!sg_miter_next(&host->sg_miter))
298                     BUG();

Which suggests that the size of the transfer was bigger than the sg list
passed to the transfer, which is worrying as this seems to suggest there
is a problem with the PIO code writing insufficient data to the card.

-- 
Ben

Q:      What's a light-year?
A:      One-third less calories than a regular year.