Message ID | 5126421D.7010204@freescale.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Hi Fabio, On Thu, 21 Feb 2013 12:49:49 -0300 Fabio Estevam <fabio.estevam@freescale.com> wrote: > Hi Anatolij, > > Anatolij Gustschin wrote: > > > this change introduces a race condition for host->req (and maybe > > for host->data) accesses. The callback is running in soft-irq context and can > > be interrupted by the mxcmci_irq() interrupt which can finish the request and > > set host->req to NULL. Then mxcmci_data_done() crashes with a null pointer > > dereference. How extensively was it tested? > > Does the patch below help? Sorry for long delay. No, it doesn't help. With this patch applied the task copying data to the sd-card hangs forever. I used following patch to fix observed crashes: http://thread.gmane.org/gmane.linux.kernel.mmc/19658/focus=19662 Thanks anyway! Anatolij -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
--- a/drivers/mmc/host/mxcmmc.c +++ b/drivers/mmc/host/mxcmmc.c @@ -309,9 +309,11 @@ static void mxcmci_dma_callback(void *data) { struct mxcmci_host *host = data; u32 stat; + unsigned int long flags; del_timer(&host->watchdog); + spin_lock_irqsave(&host->lock, flags); stat = readl(host->base + MMC_REG_STATUS); writel(stat & ~STATUS_DATA_TRANS_DONE, host->base + MMC_REG_STATUS); @@ -320,6 +322,7 @@ static void mxcmci_dma_callback(void *data) if (stat & STATUS_READ_OP_DONE) writel(STATUS_READ_OP_DONE, host->base + MMC_REG_STATUS); + spin_unlock_irqrestore(&host->lock, flags); mxcmci_data_done(host, stat); }