Calling mmc_request_done() under a spinlock with interrupts disabled leads to a recursive spin-lock on request retry path and to scheduling in atomic context. This patch fixes both these problems by moving mmc_request_done() to the scheduler workqueue.
Signed-off-by: Guennadi Liakhovetski <[email protected]> --- Morimoto-san, this should fix the race in TMIO / SDHI driver, that you reported here: http://article.gmane.org/gmane.linux.ports.sh.devel/11349 Please, verify. drivers/mmc/host/tmio_mmc.h | 2 ++ drivers/mmc/host/tmio_mmc_pio.c | 14 +++++++++++--- 2 files changed, 13 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/host/tmio_mmc.h b/drivers/mmc/host/tmio_mmc.h index 8260bc2..b4dfc13 100644 --- a/drivers/mmc/host/tmio_mmc.h +++ b/drivers/mmc/host/tmio_mmc.h @@ -73,6 +73,8 @@ struct tmio_mmc_host { /* Track lost interrupts */ struct delayed_work delayed_reset_work; + struct work_struct done; + /* protect host private data */ spinlock_t lock; unsigned long last_req_ts; }; diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c index ad6347b..1b63045 100644 --- a/drivers/mmc/host/tmio_mmc_pio.c +++ b/drivers/mmc/host/tmio_mmc_pio.c @@ -297,10 +297,16 @@ static void tmio_mmc_finish_request(struct tmio_mmc_host *host) host->mrq = NULL; - /* FIXME: mmc_request_done() can schedule! */ mmc_request_done(host->mmc, mrq); } +static void tmio_mmc_done_work(struct work_struct *work) +{ + struct tmio_mmc_host *host = container_of(work, struct tmio_mmc_host, + done); + tmio_mmc_finish_request(host); +} + /* These are the bitmasks the tmio chip requires to implement the MMC response * types. Note that R1 and R6 are the same in this scheme. */ #define APP_CMD 0x0040 @@ -467,7 +473,7 @@ void tmio_mmc_do_data_irq(struct tmio_mmc_host *host) BUG(); } - tmio_mmc_finish_request(host); + schedule_work(&host->done); } static void tmio_mmc_data_irq(struct tmio_mmc_host *host) @@ -557,7 +563,7 @@ static void tmio_mmc_cmd_irq(struct tmio_mmc_host *host, tasklet_schedule(&host->dma_issue); } } else { - tmio_mmc_finish_request(host); + schedule_work(&host->done); } out: @@ -916,6 +922,7 @@ int __devinit tmio_mmc_host_probe(struct tmio_mmc_host **host, /* Init delayed work for request timeouts */ INIT_DELAYED_WORK(&_host->delayed_reset_work, tmio_mmc_reset_work); + INIT_WORK(&_host->done, tmio_mmc_done_work); /* See if we also get DMA */ tmio_mmc_request_dma(_host, pdata); @@ -963,6 +970,7 @@ void tmio_mmc_host_remove(struct tmio_mmc_host *host) pm_runtime_get_sync(&pdev->dev); mmc_remove_host(host->mmc); + cancel_work_sync(&host->done); cancel_delayed_work_sync(&host->delayed_reset_work); tmio_mmc_release_dma(host); -- 1.7.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
