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dmaengine: sh: usb-dmac: set tx_result parameters 

[ Upstream commit 466257d996 ]

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 24461d9792 ("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: 24461d9792 ("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.shimoda.uh@renesas.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5.4-rM2-2.2.x-imx-squashed
Yoshihiro Shimoda 2020-06-18 21:07:33 +09:00 committed by Greg Kroah-Hartman
parent f5c6ebd514
commit 684a5568df
1 changed files with 2 additions and 0 deletions
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2
drivers/dma/sh/usb-dmac.c
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@ -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 */