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From:   Tudor Ambarus <tudor.ambarus@microchip.com>
To:     <vkoul@kernel.org>, <peda@axentia.se>, <du@axentia.se>,
        <regressions@leemhuis.info>
CC:     <ludovic.desroches@microchip.com>, <maciej.sosnowski@intel.com>,
        <tudor.ambarus@microchip.com>, <dan.j.williams@intel.com>,
        <nicolas.ferre@microchip.com>, <mripard@kernel.org>,
        <torfl6749@gmail.com>, <linux-kernel@vger.kernel.org>,
        <dmaengine@vger.kernel.org>,
        <linux-arm-kernel@lists.infradead.org>, <stable@vger.kernel.org>
Subject: [PATCH 18/33] dmaengine: at_hdmac: Fix completion of unissued descriptor in case of errors
Date:   Sat, 20 Aug 2022 15:57:02 +0300
Message-ID: <20220820125717.588722-19-tudor.ambarus@microchip.com>
In-Reply-To: <20220820125717.588722-1-tudor.ambarus@microchip.com>
References: <20220820125717.588722-1-tudor.ambarus@microchip.com>
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In case the controller detected an error, the code took the chance to move
all the queued (submitted) descriptors to the active (issued) list. This
was wrong as if there were any descriptors in the submitted list they were
moved to the issued list without actually issuing them to the controller,
thus a completion could be raised without even fireing the descriptor.

Fixes: dc78baa2b90b ("dmaengine: at_hdmac: new driver for the Atmel AHB DMA Controller")
Reported-by: Peter Rosin <peda@axentia.se>
Cc: stable@vger.kernel.org
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
---
 drivers/dma/at_hdmac.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index e5ac73768d13..825a29ede35e 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -974,10 +974,6 @@ static void atc_handle_error(struct at_dma_chan *atchan)
 	bad_desc = atc_first_active(atchan);
 	list_del_init(&bad_desc->desc_node);
 
-	/* As we are stopped, take advantage to push queued descriptors
-	 * in active_list */
-	list_splice_init(&atchan->queue, atchan->active_list.prev);
-
 	/* Try to restart the controller */
 	if (!list_empty(&atchan->active_list)) {
 		desc = atc_first_queued(atchan);
-- 
2.25.1