From: Peter Collingbourne Date: Thu, 14 Jan 2021 20:14:05 +0000 (-0800) Subject: mmc: core: don't initialize block size from ext_csd if not present X-Git-Tag: v5.11-rc5~27^2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b503087445ce7e45fabdee87ca9e460d5b5b5168;p=thirdparty%2Fkernel%2Flinux.git mmc: core: don't initialize block size from ext_csd if not present If extended CSD was not available, the eMMC driver would incorrectly set the block size to 0, as the data_sector_size field of ext_csd was never initialized. This issue was exposed by commit 817046ecddbc ("block: Align max_hw_sectors to logical blocksize") which caused max_sectors and max_hw_sectors to be set to 0 after setting the block size to 0, resulting in a kernel panic in bio_split when attempting to read from the device. Fix it by only reading the block size from ext_csd if it is available. Fixes: a5075eb94837 ("mmc: block: Allow disabling 512B sector size emulation") Signed-off-by: Peter Collingbourne Reviewed-by: Damien Le Moal Link: https://linux-review.googlesource.com/id/If244d178da4d86b52034459438fec295b02d6e60 Acked-by: Adrian Hunter Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210114201405.2934886-1-pcc@google.com Signed-off-by: Ulf Hansson --- diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c index de7cb0369c308..002426e3cf76c 100644 --- a/drivers/mmc/core/queue.c +++ b/drivers/mmc/core/queue.c @@ -384,8 +384,10 @@ static void mmc_setup_queue(struct mmc_queue *mq, struct mmc_card *card) "merging was advertised but not possible"); blk_queue_max_segments(mq->queue, mmc_get_max_segments(host)); - if (mmc_card_mmc(card)) + if (mmc_card_mmc(card) && card->ext_csd.data_sector_size) { block_size = card->ext_csd.data_sector_size; + WARN_ON(block_size != 512 && block_size != 4096); + } blk_queue_logical_block_size(mq->queue, block_size); /*