This is a note to let you know that I've just added the patch titled mmc: host: Return an error when ->enable_sdio_irq() ops is missing to the 5.15-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-host-return-an-error-when-enable_sdio_irq-ops-is.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 2eb3f437cb30c264e3e5d9746c2a84d5e994462e Author: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Date: Thu Mar 3 17:51:42 2022 +0100 mmc: host: Return an error when ->enable_sdio_irq() ops is missing [ Upstream commit d6c9219ca1139b74541b2a98cee47a3426d754a9 ] Even if the current WARN() notifies the user that something is severely wrong, we can still end up in a PANIC() when trying to invoke the missing ->enable_sdio_irq() ops. Therefore, let's also return an error code and prevent the host from being added. While at it, move the code into a separate function to prepare for subsequent changes and for further host caps validations. Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220303165142.129745-1-ulf.hansson@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index cf140f4ec864..d739e2b631fe 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -588,6 +588,16 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev) EXPORT_SYMBOL(mmc_alloc_host); +static int mmc_validate_host_caps(struct mmc_host *host) +{ + if (host->caps & MMC_CAP_SDIO_IRQ && !host->ops->enable_sdio_irq) { + dev_warn(host->parent, "missing ->enable_sdio_irq() ops\n"); + return -EINVAL; + } + + return 0; +} + /** * mmc_add_host - initialise host hardware * @host: mmc host @@ -600,8 +610,9 @@ int mmc_add_host(struct mmc_host *host) { int err; - WARN_ON((host->caps & MMC_CAP_SDIO_IRQ) && - !host->ops->enable_sdio_irq); + err = mmc_validate_host_caps(host); + if (err) + return err; err = device_add(&host->class_dev); if (err)