The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From bb364890323cca6e43f13e86d190ebf34a7d8cea Mon Sep 17 00:00:00 2001 From: Remi Pommarel <repk@xxxxxxxxxxxx> Date: Fri, 11 Jan 2019 00:01:35 +0100 Subject: [PATCH] mmc: meson-gx: Free irq in release() callback Because the irq was requested through device managed resources API (devm_request_threaded_irq()) it was freed after meson_mmc_remove() completion, thus after mmc_free_host() has reclaimed meson_host memory. As this irq is IRQF_SHARED, while using CONFIG_DEBUG_SHIRQ, its handler get called by free_irq(). So meson_mmc_irq() was called after the meson_host memory reclamation and was using invalid memory. We ended up with the following scenario: device_release_driver() meson_mmc_remove() mmc_free_host() /* Freeing host memory */ ... devres_release_all() devm_irq_release() __free_irq() meson_mmc_irq() /* Uses freed memory */ To avoid this, the irq is released in meson_mmc_remove() and in mseon_mmc_probe() error path before mmc_free_host() gets called. Reported-by: Elie Roudninski <xademax@xxxxxxxxx> Signed-off-by: Remi Pommarel <repk@xxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c index c2690c1a50ff..f115d7c63ffe 100644 --- a/drivers/mmc/host/meson-gx-mmc.c +++ b/drivers/mmc/host/meson-gx-mmc.c @@ -179,6 +179,8 @@ struct meson_host { struct sd_emmc_desc *descs; dma_addr_t descs_dma_addr; + int irq; + bool vqmmc_enabled; }; @@ -1231,7 +1233,7 @@ static int meson_mmc_probe(struct platform_device *pdev) struct resource *res; struct meson_host *host; struct mmc_host *mmc; - int ret, irq; + int ret; mmc = mmc_alloc_host(sizeof(struct meson_host), &pdev->dev); if (!mmc) @@ -1276,8 +1278,8 @@ static int meson_mmc_probe(struct platform_device *pdev) goto free_host; } - irq = platform_get_irq(pdev, 0); - if (irq <= 0) { + host->irq = platform_get_irq(pdev, 0); + if (host->irq <= 0) { dev_err(&pdev->dev, "failed to get interrupt resource.\n"); ret = -EINVAL; goto free_host; @@ -1331,9 +1333,8 @@ static int meson_mmc_probe(struct platform_device *pdev) writel(IRQ_CRC_ERR | IRQ_TIMEOUTS | IRQ_END_OF_CHAIN, host->regs + SD_EMMC_IRQ_EN); - ret = devm_request_threaded_irq(&pdev->dev, irq, meson_mmc_irq, - meson_mmc_irq_thread, IRQF_SHARED, - NULL, host); + ret = request_threaded_irq(host->irq, meson_mmc_irq, + meson_mmc_irq_thread, IRQF_SHARED, NULL, host); if (ret) goto err_init_clk; @@ -1351,7 +1352,7 @@ static int meson_mmc_probe(struct platform_device *pdev) if (host->bounce_buf == NULL) { dev_err(host->dev, "Unable to map allocate DMA bounce buffer.\n"); ret = -ENOMEM; - goto err_init_clk; + goto err_free_irq; } host->descs = dma_alloc_coherent(host->dev, SD_EMMC_DESC_BUF_LEN, @@ -1370,6 +1371,8 @@ static int meson_mmc_probe(struct platform_device *pdev) err_bounce_buf: dma_free_coherent(host->dev, host->bounce_buf_size, host->bounce_buf, host->bounce_dma_addr); +err_free_irq: + free_irq(host->irq, host); err_init_clk: clk_disable_unprepare(host->mmc_clk); err_core_clk: @@ -1387,6 +1390,7 @@ static int meson_mmc_remove(struct platform_device *pdev) /* disable interrupts */ writel(0, host->regs + SD_EMMC_IRQ_EN); + free_irq(host->irq, host); dma_free_coherent(host->dev, SD_EMMC_DESC_BUF_LEN, host->descs, host->descs_dma_addr);