3.18-stable review patch. If anyone has any objections, please let me know.
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From: Hans de Goede hdegoede@redhat.com
commit 2cfce3a86b64b53f0a70e92a6a659c720c319b45 upstream.
Commit 184add2ca23c ("libata: Apply NOLPM quirk for SanDisk SD7UB3Q*G1001 SSDs") disabled LPM for SanDisk SD7UB3Q*G1001 SSDs.
This has lead to several reports of users of that SSD where LPM was working fine and who know have a significantly increased idle power consumption on their laptops.
Likely there is another problem on the T450s from the original reporter which gets exposed by the uncore reaching deeper sleep states (higher PC-states) due to LPM being enabled. The problem as reported, a hardfreeze about once a day, already did not sound like it would be caused by LPM and the reports of the SSD working fine confirm this. The original reporter is ok with dropping the quirk.
A X250 user has reported the same hard freeze problem and for him the problem went away after unrelated updates, I suspect some GPU driver stack changes fixed things.
TL;DR: The original reporters problem were triggered by LPM but not an LPM issue, so drop the quirk for the SSD in question.
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1583207 Cc: stable@vger.kernel.org Cc: Richard W.M. Jones rjones@redhat.com Cc: Lorenzo Dalrio lorenzo.dalrio@gmail.com Reported-by: Lorenzo Dalrio lorenzo.dalrio@gmail.com Signed-off-by: Hans de Goede hdegoede@redhat.com Signed-off-by: Tejun Heo tj@kernel.org Acked-by: "Richard W.M. Jones" rjones@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/ata/libata-core.c | 3 --- 1 file changed, 3 deletions(-)
--- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -4248,9 +4248,6 @@ static const struct ata_blacklist_entry ATA_HORKAGE_ZERO_AFTER_TRIM | ATA_HORKAGE_NOLPM, },
- /* Sandisk devices which are known to not handle LPM well */ - { "SanDisk SD7UB3Q*G1001", NULL, ATA_HORKAGE_NOLPM, }, - /* devices that don't properly handle queued TRIM commands */ { "Micron_M500_*", NULL, ATA_HORKAGE_NO_NCQ_TRIM | ATA_HORKAGE_ZERO_AFTER_TRIM, },