From: Nicolas Ferre Date: Tue, 11 May 2010 21:06:49 +0000 (-0700) Subject: mmc: atmel-mci: prevent kernel oops while removing card X-Git-Tag: v2.6.32.14~27 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=eac2ef18972dbc56c2540c7302a6c7a1437352ef;p=karo-tx-linux.git mmc: atmel-mci: prevent kernel oops while removing card commit 009a891b22395fc86e5f34057d79fffee4509ab5 upstream. The removing of an SD card in certain circumstances can lead to a kernel oops if we do not make sure that the "data" field of the host structure is valid. This patch adds a test in atmci_dma_cleanup() function and also calls atmci_stop_dma() before throwing away the reference to data. Signed-off-by: Nicolas Ferre Cc: Haavard Skinnemoen Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/mmc/host/atmel-mci.c b/drivers/mmc/host/atmel-mci.c index 176578826245..67a0fe0e2a0f 100644 --- a/drivers/mmc/host/atmel-mci.c +++ b/drivers/mmc/host/atmel-mci.c @@ -530,9 +530,10 @@ static void atmci_dma_cleanup(struct atmel_mci *host) { struct mmc_data *data = host->data; - dma_unmap_sg(&host->pdev->dev, data->sg, data->sg_len, - ((data->flags & MMC_DATA_WRITE) - ? DMA_TO_DEVICE : DMA_FROM_DEVICE)); + if (data) + dma_unmap_sg(&host->pdev->dev, data->sg, data->sg_len, + ((data->flags & MMC_DATA_WRITE) + ? DMA_TO_DEVICE : DMA_FROM_DEVICE)); } static void atmci_stop_dma(struct atmel_mci *host) @@ -1037,8 +1038,8 @@ static void atmci_command_complete(struct atmel_mci *host, "command error: status=0x%08x\n", status); if (cmd->data) { - host->data = NULL; atmci_stop_dma(host); + host->data = NULL; mci_writel(host, IDR, MCI_NOTBUSY | MCI_TXRDY | MCI_RXRDY | ATMCI_DATA_ERROR_FLAGS);