Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
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 15/33] dmaengine: at_hdmac: Free the memset buf without holding the chan lock
Date:   Sat, 20 Aug 2022 15:56:59 +0300
Message-ID: <20220820125717.588722-16-tudor.ambarus@microchip.com>
In-Reply-To: <20220820125717.588722-1-tudor.ambarus@microchip.com>
References: <20220820125717.588722-1-tudor.ambarus@microchip.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/plain
Precedence: bulk

There's no need to hold the channel lock when freeing the memset buf, as
the operation has already completed. Free the memset buf without holding
the channel lock.

Fixes: 4d112426c344 ("dmaengine: hdmac: Add memset capabilities")
Reported-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/lkml/13c6c9a2-6db5-c3bf-349b-4c127ad3496a@axentia.se/
---
 drivers/dma/at_hdmac.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index b3184da7ced4..c2b3d7b63920 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -897,13 +897,6 @@ atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc)
 	if (!atc_chan_is_cyclic(atchan))
 		dma_cookie_complete(txd);
 
-	/* If the transfer was a memset, free our temporary buffer */
-	if (desc->memset_buffer) {
-		dma_pool_free(atdma->memset_pool, desc->memset_vaddr,
-			      desc->memset_paddr);
-		desc->memset_buffer = false;
-	}
-
 	/* Remove transfer node from the active list. */
 	list_del_init(&desc->desc_node);
 	spin_unlock_irqrestore(&atchan->lock, flags);
@@ -922,6 +915,13 @@ atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc)
 	/* add myself to free_list */
 	list_add(&desc->desc_node, &atchan->free_list);
 	spin_unlock_irqrestore(&atchan->lock, flags);
+
+	/* If the transfer was a memset, free our temporary buffer */
+	if (desc->memset_buffer) {
+		dma_pool_free(atdma->memset_pool, desc->memset_vaddr,
+			      desc->memset_paddr);
+		desc->memset_buffer = false;
+	}
 }
 
 /**
-- 
2.25.1