From 4c13483e1fa4e8ebfdbebf9f4257bca4d26b3834 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Reimar=20D=C3=B6ffinger?= <Reimar.Doeffinger@gmx.de>
Date: Tue, 12 Oct 2021 08:27:44 +0200
Subject: [PATCH] libata: fix checking of DMA state
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Git-commit: f971a85439bd25dc7b4d597cf5e4e8dc7ffc884b
Patch-mainline: v5.16-rc1
References: stable-5.14.19
commit f971a85439bd25dc7b4d597cf5e4e8dc7ffc884b upstream.
Checking if DMA is enabled should be done via the
ata_dma_enabled helper function, since the init state
0xff indicates disabled.
This meant that ATA_CMD_READ_LOG_DMA_EXT was used and probed
for before DMA was enabled, which caused hangs for some combinations
of controllers and devices.
It might also have caused it to be incorrectly disabled as broken,
but there have been no reports of that.
Cc: stable@vger.kernel.org
Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=195895
Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Tested-by: Paul Menzel <pmenzel@molgen.mpg.de>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/ata/libata-core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 8916163d508e..8acf99b88b21 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2004,7 +2004,7 @@ unsigned int ata_read_log_page(struct ata_device *dev, u8 log,
retry:
ata_tf_init(dev, &tf);
- if (dev->dma_mode && ata_id_has_read_log_dma_ext(dev->id) &&
+ if (ata_dma_enabled(dev) && ata_id_has_read_log_dma_ext(dev->id) &&
!(dev->horkage & ATA_HORKAGE_NO_DMA_LOG)) {
tf.command = ATA_CMD_READ_LOG_DMA_EXT;
tf.protocol = ATA_PROT_DMA;
--
2.26.2