linux-kernel - [PATCH AUTOSEL for 4.14 028/110] spi: atmel: fixed spin_lock usage inside atmel_spi

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20180203180015.29073-28-alexander.levin@microsoft.com>
Date:   Sat, 3 Feb 2018 18:00:41 +0000
From:   Sasha Levin <Alexander.Levin@...rosoft.com>
To:     "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "stable@...r.kernel.org" <stable@...r.kernel.org>
CC:     Radu Pirea <radu.pirea@...rochip.com>,
        Mark Brown <broonie@...nel.org>,
        Sasha Levin <Alexander.Levin@...rosoft.com>
Subject: [PATCH AUTOSEL for 4.14 028/110] spi: atmel: fixed spin_lock usage
 inside atmel_spi_remove

From: Radu Pirea <radu.pirea@...rochip.com>

[ Upstream commit 66e900a3d225575c8b48b59ae1fe74bb6e5a65cc ]

The only part of atmel_spi_remove which needs to be atomic is hardware
reset.

atmel_spi_stop_dma calls dma_terminate_all and this needs interrupts
enabled.
atmel_spi_release_dma calls dma_release_channel and dma_release_channel
locks a mutex inside of spin_lock.

So the call of these functions can't be inside a spin_lock.

Reported-by: Jia-Ju Bai <baijiaju1990@...il.com>
Signed-off-by: Radu Pirea <radu.pirea@...rochip.com>
Signed-off-by: Mark Brown <broonie@...nel.org>
Signed-off-by: Sasha Levin <alexander.levin@...rosoft.com>
---
 drivers/spi/spi-atmel.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index f95da364c283..669470971023 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -1661,12 +1661,12 @@ static int atmel_spi_remove(struct platform_device *pdev)
 	pm_runtime_get_sync(&pdev->dev);
 
 	/* reset the hardware and block queue progress */
-	spin_lock_irq(&as->lock);
 	if (as->use_dma) {
 		atmel_spi_stop_dma(master);
 		atmel_spi_release_dma(master);
 	}
 
+	spin_lock_irq(&as->lock);
 	spi_writel(as, CR, SPI_BIT(SWRST));
 	spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
 	spi_readl(as, SR);
-- 
2.11.0