SET_BLOCK_COUNT CMD23 is needed for all access to RPMB partition. If block count is not set by CMD23, all subsequent read/write commands fail as per eMMC specification. So, If the host does not support CMD23, do not expose RPMB partition. Accessing RPMB partition can cause hang / huge delay for host which do not support CMD23. Signed-off-by: Balaji T K <balajitk@xxxxxx> Reported-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx> --- drivers/mmc/core/mmc.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index e6e3911..089e8ea 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -496,7 +496,7 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd) * RPMB regions are defined in multiples of 128K. */ card->ext_csd.raw_rpmb_size_mult = ext_csd[EXT_CSD_RPMB_MULT]; - if (ext_csd[EXT_CSD_RPMB_MULT]) { + if (ext_csd[EXT_CSD_RPMB_MULT] && mmc_host_cmd23(card->host)) { mmc_part_add(card, ext_csd[EXT_CSD_RPMB_MULT] << 17, EXT_CSD_PART_CONFIG_ACC_RPMB, "rpmb", 0, false, -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html