On 11/21/2011 08:56 AM, Raja Mani wrote: > Firmware crashes while starting Soft AP in 32 bit x86 platform. > The reason is that the single dma buffer (ar_sdio->dma_buffer) > is used in ath6kl_sdio_read_write_sync() for unaligned buffer > handling and this function is called in the multiple context > at the same time. So, finally hits dma buffer corruption and > firmware crash. > > Mutex is used to protect dma buffer to avoid data corruption. > Spin lock can not used to fix this issue since mmc stack > read/write calls may for sleep. > > Observed this issue with recently commited patch > "ath6kl: Claim sdio function only at appropriate places" > 861dd058f495973c7ad2a44b8f68f3cc05733eab > > Signed-off-by: Raja Mani <rmani@xxxxxxxxxxxxxxxx> I really would not like to add yet another lock (or mutex) to ath6kl, but I don't see any other quick fix for this. So I have applied this for now, but I hope that in the future we get to remove the ugly bounce buffer altogether. But I did minor changes in the patch: I added a comment to the mutex (which I now require for all new locks), renamed the lock to something easier and moved it after the buffer. Kalle -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
