diff mbox series

libata: add kernel parameter to force ATA_HORKAGE_NO_DMA_LOG

Message ID 20210317180413.2992-1-Reimar.Doeffinger@gmx.de
State New
Headers show
Series libata: add kernel parameter to force ATA_HORKAGE_NO_DMA_LOG | expand

Commit Message

Reimar Döffinger March 17, 2021, 6:04 p.m. UTC 
The ATA_CMD_READ_LOG_DMA_EXT can cause controller/device to
become unresponsive until the next power cycle.
This seems to particularly affect IDE to SATA adapters,
possibly in combination with certain SATA SSDs, though
there might be more/different cases.
Comment 5 of https://bugzilla.kernel.org/show_bug.cgi?id=195895
is an example.
Having an option to disable its use allows booting systems affected,
which besides being a useful workaround is also a necessary
step to allow gathering more debug info on these systems.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
---
 Documentation/admin-guide/kernel-parameters.txt | 2 ++
 drivers/ata/libata-core.c                       | 2 ++
 2 files changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 04545725f187..d2428b3b98f1 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -2473,6 +2473,8 @@ 
 
 			* [no]ncqtrim: Turn off queued DSM TRIM.
 
+			* [no]dmalog: Turn off use of ATA_CMD_READ_LOG_DMA_EXT (0x47) command
+
 			* nohrst, nosrst, norst: suppress hard, soft
 			  and both resets.
 
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 61c762961ca8..7fb865333a38 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -6104,6 +6104,8 @@  static int __init ata_parse_force_one(char **cur,
 		{ "ncq",	.horkage_off	= ATA_HORKAGE_NONCQ },
 		{ "noncqtrim",	.horkage_on	= ATA_HORKAGE_NO_NCQ_TRIM },
 		{ "ncqtrim",	.horkage_off	= ATA_HORKAGE_NO_NCQ_TRIM },
+		{ "nodmalog",	.horkage_on	= ATA_HORKAGE_NO_DMA_LOG },
+		{ "dmalog",	.horkage_off	= ATA_HORKAGE_NO_DMA_LOG },
 		{ "dump_id",	.horkage_on	= ATA_HORKAGE_DUMP_ID },
 		{ "pio0",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 0) },
 		{ "pio1",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 1) },