This is a note to let you know that I've just added the patch titled mmc: core: Return correct emmc response in case of ioctl error to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mmc-core-return-correct-emmc-response-in-case-of-ioc.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 95e3dfe08fa907cbad9850ef363be66b45797ddc Author: Nishad Kamdar <nishadkamdar@xxxxxxxxx> Date: Wed Aug 25 00:47:26 2021 +0530 mmc: core: Return correct emmc response in case of ioctl error [ Upstream commit e72a55f2e5ddcfb3dce0701caf925ce435b87682 ] When a read/write command is sent via ioctl to the kernel, and the command fails, the actual error response of the emmc is not sent to the user. IOCTL read/write tests are carried out using commands 17 (Single BLock Read), 24 (Single Block Write), 18 (Multi Block Read), 25 (Multi Block Write) The tests are carried out on a 64Gb emmc device. All of these tests try to access an "out of range" sector address (0x09B2FFFF). It is seen that without the patch the response received by the user is not OUT_OF_RANGE error (R1 response 31st bit is not set) as per JEDEC specification. After applying the patch proper response is seen. This is because the function returns without copying the response to the user in case of failure. This patch fixes the issue. Hence, this memcpy is required whether we get an error response or not. Therefor it is moved up from the current position up to immediately after we have called mmc_wait_for_req(). The test code and the output of only the CMD17 is included in the commit to limit the message length. CMD17 (Test Code Snippet): ========================== printf("Forming CMD%d\n", opt_idx); /* single block read */ cmd.blksz = 512; cmd.blocks = 1; cmd.write_flag = 0; cmd.opcode = 17; //cmd.arg = atoi(argv[3]); cmd.arg = 0x09B2FFFF; /* Expecting response R1B */ cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC; memset(data, 0, sizeof(__u8) * 512); mmc_ioc_cmd_set_data(cmd, data); printf("Sending CMD%d: ARG[0x%08x]\n", opt_idx, cmd.arg); if(ioctl(fd, MMC_IOC_CMD, &cmd)) perror("Error"); printf("\nResponse: %08x\n", cmd.response[0]); CMD17 (Output without patch): ============================= test@test-LIVA-Z:~$ sudo ./mmc cmd_test /dev/mmcblk0 17 Entering the do_mmc_commands:Device: /dev/mmcblk0 nargs:4 Entering the do_mmc_commands:Device: /dev/mmcblk0 options[17, 0x09B2FFF] Forming CMD17 Sending CMD17: ARG[0x09b2ffff] Error: Connection timed out Response: 00000000 (Incorrect response) CMD17 (Output with patch): ========================== test@test-LIVA-Z:~$ sudo ./mmc cmd_test /dev/mmcblk0 17 [sudo] password for test: Entering the do_mmc_commands:Device: /dev/mmcblk0 nargs:4 Entering the do_mmc_commands:Device: /dev/mmcblk0 options[17, 09B2FFFF] Forming CMD17 Sending CMD17: ARG[0x09b2ffff] Error: Connection timed out Response: 80000900 (Correct OUT_OF_ERROR response as per JEDEC specification) Signed-off-by: Nishad Kamdar <nishadkamdar@xxxxxxxxx> Reviewed-by: Avri Altman <avri.altman@xxxxxxx> Link: https://lore.kernel.org/r/20210824191726.8296-1-nishadkamdar@xxxxxxxxx Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c index 7b2bb32e3555..d1cc0fdbc51c 100644 --- a/drivers/mmc/core/block.c +++ b/drivers/mmc/core/block.c @@ -592,6 +592,7 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md, } mmc_wait_for_req(card->host, &mrq); + memcpy(&idata->ic.response, cmd.resp, sizeof(cmd.resp)); if (cmd.error) { dev_err(mmc_dev(card->host), "%s: cmd error %d\n", @@ -641,8 +642,6 @@ static int __mmc_blk_ioctl_cmd(struct mmc_card *card, struct mmc_blk_data *md, if (idata->ic.postsleep_min_us) usleep_range(idata->ic.postsleep_min_us, idata->ic.postsleep_max_us); - memcpy(&(idata->ic.response), cmd.resp, sizeof(cmd.resp)); - if (idata->rpmb || (cmd.flags & MMC_RSP_R1B) == MMC_RSP_R1B) { /* * Ensure RPMB/R1B command has completed by polling CMD13