On Fri, 11 Jun 2021 11:56:16 +0200, Adrian Hunter wrote: > > On 11/06/21 12:03 pm, Takashi Iwai wrote: > > When DMA-mapping of the bounce buffer fails, the driver tries to fall > > back, but it leaves the allocated host->bounce_buffer although its > > size is zero. Later on, the driver checks the use of bounce buffer > > with host->bounce_buffer pointer, and it tries to use the buffer > > incorrectly, resulting in Oops. > > > > This patch clears the release the unused buffer and clears the > > bounce_buffer pointer for addressing the problem. > > > > Signed-off-by: Takashi Iwai <tiwai@xxxxxxx> > > One minor comment below, otherwise: > > Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> > > > --- > > drivers/mmc/host/sdhci.c | 6 +++++- > > 1 file changed, 5 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > > index bf238ade1602..5f467b98ca88 100644 > > --- a/drivers/mmc/host/sdhci.c > > +++ b/drivers/mmc/host/sdhci.c > > @@ -4072,9 +4072,13 @@ static void sdhci_allocate_bounce_buffer(struct sdhci_host *host) > > bounce_size, > > DMA_BIDIRECTIONAL); > > ret = dma_mapping_error(mmc_dev(mmc), host->bounce_addr); > > - if (ret) > > + if (ret) { > > + devm_kfree(mmc->parent, host->bounce_buffer); > > Everywhere else in this function mmc_dev(mmc) is used, so maybe > use it here too instead of mmc->parent. Doh, right, I wrote a patch based on the older kernel and refreshed afterwards, but I forgot correcting this place. Will resubmit the fixed version. thanks, Takashi