Commit 054cedff authored Jan 26, 2016 by Russell King Committed by Ulf Hansson Feb 29, 2016

mmc: sdhci: plug DMA mapping leak on error



If we terminate a command early, we fail to properly clean up the DMA
mappings for the data part of the request.  Put this clean up to the
tasklet, which is the common path for finishing a request so we always
clean up after ourselves.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[ Split original patch so that it now contains only the fix ]
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org # v4.5+
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

parent edd63fcc

drivers/mmc/host/sdhci.c

+16 −0

Original line number	Diff line number	Diff line
		@@ -2207,6 +2207,22 @@ static void sdhci_tasklet_finish(unsigned long param)

		mrq = host->mrq;

		/*
		* Always unmap the data buffers if they were mapped by
		* sdhci_prepare_data() whenever we finish with a request.
		* This avoids leaking DMA mappings on error.
		*/
		if (host->flags & SDHCI_REQ_USE_DMA) {
		struct mmc_data *data = mrq->data;

		if (data && data->host_cookie == COOKIE_MAPPED) {
		dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
		(data->flags & MMC_DATA_READ) ?
		DMA_FROM_DEVICE : DMA_TO_DEVICE);
		data->host_cookie = COOKIE_UNMAPPED;
		}
		}

		/*
		* The controller needs a reset of internal state machines
		* upon error conditions.