4.5-stable review patch. If anyone has any objections, please let me know.
------------------ From: Russell King <[email protected]> commit 771a3dc225815b7cc691c1ce703a3af8488e48df upstream. sdhci_post_req() exists to unmap a previously mapped but already finished request, while the next request is in progress. However, the state of the SDHCI_REQ_USE_DMA flag depends on the last submitted request. This means we can end up clearing the flag due to a quirk, which then means that sdhci_post_req() fails to unmap the DMA buffer, potentially leading to data corruption. We can safely ignore the SDHCI_REQ_USE_DMA here, as testing data->host_cookie is entirely sufficient. Signed-off-by: Russell King <[email protected]> [ Re-based to apply as a separate fix ] Signed-off-by: Adrian Hunter <[email protected]> Tested-by: Gregory CLEMENT <[email protected]> Signed-off-by: Ulf Hansson <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/mmc/host/sdhci.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2115,14 +2115,13 @@ static void sdhci_post_req(struct mmc_ho struct sdhci_host *host = mmc_priv(mmc); struct mmc_data *data = mrq->data; - if (host->flags & SDHCI_REQ_USE_DMA) { - if (data->host_cookie == COOKIE_GIVEN || - data->host_cookie == COOKIE_MAPPED) - dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len, - data->flags & MMC_DATA_WRITE ? - DMA_TO_DEVICE : DMA_FROM_DEVICE); - data->host_cookie = COOKIE_UNMAPPED; - } + if (data->host_cookie == COOKIE_GIVEN || + data->host_cookie == COOKIE_MAPPED) + dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len, + data->flags & MMC_DATA_WRITE ? + DMA_TO_DEVICE : DMA_FROM_DEVICE); + + data->host_cookie = COOKIE_UNMAPPED; } static int sdhci_pre_dma_transfer(struct sdhci_host *host,
