From: Yoshihiro Shimoda yoshihiro.shimoda.uh@renesas.com
[ Upstream commit 466257d9968ac79575831250b039dc07566c7b13 ]
A client driver (renesas_usbhs) assumed that dmaengine_tx_status() could return the residue even if the transfer was completed. However, this was not correct usage [1] and this caused to break getting the residue after the commit 24461d9792c2 ("dmaengine: virt-dma: Fix access after free in vchan_complete()") actually. So, this is possible to get wrong received size if the usb controller gets a short packet. For example, g_zero driver causes "bad OUT byte" errors.
To use the tx_result from the renesas_usbhs driver when the transfer is completed, set the tx_result parameters.
Notes that the renesas_usbhs driver needs to update for it.
[1] https://lore.kernel.org/dmaengine/20200616165550.GP2324254@vkoul-mobl/
Reported-by: Hien Dang hien.dang.eb@renesas.com Fixes: 24461d9792c2 ("dmaengine: virt-dma: Fix access after free in vchan_complete()") Signed-off-by: Yoshihiro Shimoda yoshihiro.shimoda.uh@renesas.com Link: https://lore.kernel.org/r/1592482053-19433-1-git-send-email-yoshihiro.shimod... Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/dma/sh/usb-dmac.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/dma/sh/usb-dmac.c b/drivers/dma/sh/usb-dmac.c index b218a013c2600..8f7ceb698226c 100644 --- a/drivers/dma/sh/usb-dmac.c +++ b/drivers/dma/sh/usb-dmac.c @@ -586,6 +586,8 @@ static void usb_dmac_isr_transfer_end(struct usb_dmac_chan *chan) desc->residue = usb_dmac_get_current_residue(chan, desc, desc->sg_index - 1); desc->done_cookie = desc->vd.tx.cookie; + desc->vd.tx_result.result = DMA_TRANS_NOERROR; + desc->vd.tx_result.residue = desc->residue; vchan_cookie_complete(&desc->vd);
/* Restart the next transfer if this driver has a next desc */