In function sdhci_request(), it is possible to do the tuning execution
like below:
sdhci_request() {
spin_lock_irqsave(&host->lock, flags);
host->mrq = mrq;
...
spin_unlock_irqrestore(&host->lock, flags);
<=== Here it is possible one pending finish_tasklet get running
and it will operate the original mrq, and notified the mrq
is done, and causes memory corruption.
sdhci_execute_tuning(mmc, tuning_opcode);
spin_lock_irqsave(&host->lock, flags);
host->mrq = mrq;
...
}
In the above race place, the original mrq should not be finished wrongly,
so here before unlock the spinlock, we need to set the host->mrq to NULL
to avoid this case.
Signed-off-by: Liu, Chuansheng <chuansheng.liu@xxxxxxxxx>
---
drivers/mmc/host/sdhci.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 7a7fb4f..c7a001a 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1391,6 +1391,13 @@ static void sdhci_request(struct mmc_host *mmc, struct mmc_request *mrq)
mmc->card->type == MMC_TYPE_MMC ?
MMC_SEND_TUNING_BLOCK_HS200 :
MMC_SEND_TUNING_BLOCK;
+
+ /* Here we need to set the host->mrq to NULL,
+ * in case the penging finish_tasklet
+ * operates it wrongly.
+ */
+ host->mrq = NULL;
+
spin_unlock_irqrestore(&host->lock, flags);
sdhci_execute_tuning(mmc, tuning_opcode);
spin_lock_irqsave(&host->lock, flags);
--
1.7.9.5
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
