From: Greg Kroah-Hartman gregkh@linuxfoundation.org
From: Chaotian Jing chaotian.jing@mediatek.com
[ Upstream commit 0354ca6edd464a2cf332f390581977b8699ed081 ]
when get request SW timeout, if CMD/DAT xfer done irq coming right now, then there is race between the msdc_request_timeout work and irq handler, and the host->cmd and host->data may set to NULL in irq handler. also, current flow ensure that only one path can go to msdc_request_done(), so no need check the return value of cancel_delayed_work().
Signed-off-by: Chaotian Jing chaotian.jing@mediatek.com Link: https://lore.kernel.org/r/20201218071611.12276-1-chaotian.jing@mediatek.com Signed-off-by: Ulf Hansson ulf.hansson@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/mmc/host/mtk-sd.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c index 5ef25463494f..1770c8df9d1b 100644 --- a/drivers/mmc/host/mtk-sd.c +++ b/drivers/mmc/host/mtk-sd.c @@ -720,13 +720,13 @@ static void msdc_track_cmd_data(struct msdc_host *host, static void msdc_request_done(struct msdc_host *host, struct mmc_request *mrq) { unsigned long flags; - bool ret;
- ret = cancel_delayed_work(&host->req_timeout); - if (!ret) { - /* delay work already running */ - return; - } + /* + * No need check the return value of cancel_delayed_work, as only ONE + * path will go here! + */ + cancel_delayed_work(&host->req_timeout); + spin_lock_irqsave(&host->lock, flags); host->mrq = NULL; spin_unlock_irqrestore(&host->lock, flags); @@ -747,7 +747,7 @@ static bool msdc_cmd_done(struct msdc_host *host, int events, bool done = false; bool sbc_error; unsigned long flags; - u32 *rsp = cmd->resp; + u32 *rsp;
if (mrq->sbc && cmd == mrq->cmd && (events & (MSDC_INT_ACMDRDY | MSDC_INT_ACMDCRCERR @@ -768,6 +768,7 @@ static bool msdc_cmd_done(struct msdc_host *host, int events,
if (done) return true; + rsp = cmd->resp;
sdr_clr_bits(host->base + MSDC_INTEN, cmd_ints_mask);
@@ -942,7 +943,7 @@ static void msdc_data_xfer_next(struct msdc_host *host, static bool msdc_data_xfer_done(struct msdc_host *host, u32 events, struct mmc_request *mrq, struct mmc_data *data) { - struct mmc_command *stop = data->stop; + struct mmc_command *stop; unsigned long flags; bool done; unsigned int check_data = events & @@ -958,6 +959,7 @@ static bool msdc_data_xfer_done(struct msdc_host *host, u32 events,
if (done) return true; + stop = data->stop;
if (check_data || (stop && stop->error)) { dev_dbg(host->dev, "DMA status: 0x%8X\n",