This is a note to let you know that I've just added the patch titled mmc: cqhci: Fix random crash when remove mmc module/card to the 5.4-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-cqhci-fix-random-crash-when-remove-mmc-module-card.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From f06391c45e83f9a731045deb23df7cc3814fd795 Mon Sep 17 00:00:00 2001 From: Frank Li <lznuaa@xxxxxxxxx> Date: Wed, 3 Mar 2021 11:42:48 -0600 Subject: mmc: cqhci: Fix random crash when remove mmc module/card From: Frank Li <lznuaa@xxxxxxxxx> commit f06391c45e83f9a731045deb23df7cc3814fd795 upstream. [ 6684.493350] Unable to handle kernel paging request at virtual address ffff800011c5b0f0 [ 6684.498531] mmc0: card 0001 removed [ 6684.501556] Mem abort info: [ 6684.509681] ESR = 0x96000047 [ 6684.512786] EC = 0x25: DABT (current EL), IL = 32 bits [ 6684.518394] SET = 0, FnV = 0 [ 6684.521707] EA = 0, S1PTW = 0 [ 6684.524998] Data abort info: [ 6684.528236] ISV = 0, ISS = 0x00000047 [ 6684.532986] CM = 0, WnR = 1 [ 6684.536129] swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000081b22000 [ 6684.543923] [ffff800011c5b0f0] pgd=00000000bffff003, p4d=00000000bffff003, pud=00000000bfffe003, pmd=00000000900e1003, pte=0000000000000000 [ 6684.557915] Internal error: Oops: 96000047 [#1] PREEMPT SMP [ 6684.564240] Modules linked in: sdhci_esdhc_imx(-) sdhci_pltfm sdhci cqhci mmc_block mmc_core fsl_jr_uio caam_jr caamkeyblob_desc caamhash_desc caamalg_desc crypto_engine rng_core authenc libdes crct10dif_ce flexcan can_dev caam error [last unloaded: mmc_core] [ 6684.587281] CPU: 0 PID: 79138 Comm: kworker/0:3H Not tainted 5.10.9-01410-g3ba33182767b-dirty #10 [ 6684.596160] Hardware name: Freescale i.MX8DXL EVK (DT) [ 6684.601320] Workqueue: kblockd blk_mq_run_work_fn [ 6684.606094] pstate: 40000005 (nZcv daif -PAN -UAO -TCO BTYPE=--) [ 6684.612286] pc : cqhci_request+0x148/0x4e8 [cqhci] ^GMessage from syslogd@ at Thu Jan 1 01:51:24 1970 ...[ 6684.617085] lr : cqhci_request+0x314/0x4e8 [cqhci] [ 6684.626734] sp : ffff80001243b9f0 [ 6684.630049] x29: ffff80001243b9f0 x28: ffff00002c3dd000 [ 6684.635367] x27: 0000000000000001 x26: 0000000000000001 [ 6684.640690] x25: ffff00002c451000 x24: 000000000000000f [ 6684.646007] x23: ffff000017e71c80 x22: ffff00002c451000 [ 6684.651326] x21: ffff00002c0f3550 x20: ffff00002c0f3550 [ 6684.656651] x19: ffff000017d46880 x18: ffff00002cea1500 [ 6684.661977] x17: 0000000000000000 x16: 0000000000000000 [ 6684.667294] x15: 000001ee628e3ed1 x14: 0000000000000278 [ 6684.672610] x13: 0000000000000001 x12: 0000000000000001 [ 6684.677927] x11: 0000000000000000 x10: 0000000000000000 [ 6684.683243] x9 : 000000000000002b x8 : 0000000000001000 [ 6684.688560] x7 : 0000000000000010 x6 : ffff00002c0f3678 [ 6684.693886] x5 : 000000000000000f x4 : ffff800011c5b000 [ 6684.699211] x3 : 000000000002d988 x2 : 0000000000000008 [ 6684.704537] x1 : 00000000000000f0 x0 : 0002d9880008102f [ 6684.709854] Call trace: [ 6684.712313] cqhci_request+0x148/0x4e8 [cqhci] [ 6684.716803] mmc_cqe_start_req+0x58/0x68 [mmc_core] [ 6684.721698] mmc_blk_mq_issue_rq+0x460/0x810 [mmc_block] [ 6684.727018] mmc_mq_queue_rq+0x118/0x2b0 [mmc_block] The problem occurs when cqhci_request() get called after cqhci_disable() as it leads to access of allocated memory that has already been freed. Let's fix the problem by calling cqhci_disable() a bit later in the remove path. Signed-off-by: Frank Li <Frank.Li@xxxxxxx> Diagnosed-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> Link: https://lore.kernel.org/r/20210303174248.542175-1-Frank.Li@xxxxxxx Fixes: f690f4409ddd ("mmc: mmc: Enable CQE's") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/mmc/core/bus.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) --- a/drivers/mmc/core/bus.c +++ b/drivers/mmc/core/bus.c @@ -373,11 +373,6 @@ void mmc_remove_card(struct mmc_card *ca mmc_remove_card_debugfs(card); #endif - if (host->cqe_enabled) { - host->cqe_ops->cqe_disable(host); - host->cqe_enabled = false; - } - if (mmc_card_present(card)) { if (mmc_host_is_spi(card->host)) { pr_info("%s: SPI card removed\n", @@ -390,6 +385,10 @@ void mmc_remove_card(struct mmc_card *ca of_node_put(card->dev.of_node); } + if (host->cqe_enabled) { + host->cqe_ops->cqe_disable(host); + host->cqe_enabled = false; + } + put_device(&card->dev); } - Patches currently in stable-queue which might be from lznuaa@xxxxxxxxx are queue-5.4/mmc-cqhci-fix-random-crash-when-remove-mmc-module-card.patch