With 3.14.29 (and older kernels) some of my I.mx6 Sabrelite boards were crashing with the following oops: sdhci: Secure Digital Host Controller Interface driver sdhci: Copyright(c) Pierre Ossman sdhci-pltfm: SDHCI platform and OF driver helper sdhci-esdhc-imx 2198000.usdhc: could not get ultra high speed state, work on normal mode mmc0: no vqmmc regulator found mmc0: SDHCI controller on 2198000.usdhc [2198000.usdhc] using ADMA Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = c0004000 [00000000] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.14.29 #1 task: c08a7120 ti: c089c000 task.ti: c089c000 PC is at wake_up_process+0x8/0x40 LR is at sdhci_irq+0x748/0x9c4 Full boot log can be found at: http://storage.kernelci.org/stable/v3.14.29/arm-multi_v7_defconfig/lab-collabora/boot-imx6q-sabrelite.html This happens if the sdhci interrupt status contains SDHCI_INT_CARD_INT, while the sdio irq was never setup. This patch fixes that in a minimal way by checking if the sdio irq was setup. In more recent kernels this bug went away due to refactoring done by Russel King. So an alternative (potentially better?) fix for this patch is to cherrypick the following patches from a recent kernel: 18258f7239a6 - genirq: Provide synchronize_hardirq() bf3b5ec66bd0 - mmc: sdio_irq: rework sdio irq handling 41005003bcaf - mmc: sdhci: clean up interrupt handling 781e989cf593 - mmc: sdhci: convert to new SDIO IRQ handling Signed-off-by: Sjoerd Simons <sjoerd.simons@xxxxxxxxxxxxxxx> --- drivers/mmc/host/sdhci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 7e01763..881bf89 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2537,7 +2537,7 @@ out: /* * We have to delay this as it calls back into the driver. */ - if (cardint) + if (cardint && host->mmc->sdio_irqs) mmc_signal_sdio_irq(host->mmc); return result; -- 2.1.4 -- 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
