This is a note to let you know that I've just added the patch titled libata: Ignore spurious PHY event on LPM policy change to the 3.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: libata-ignore-spurious-phy-event-on-lpm-policy-change.patch and it can be found in the queue-3.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 09c5b4803a80a5451d950d6a539d2eb311dc0fb1 Mon Sep 17 00:00:00 2001 From: Gabriele Mazzotta <gabriele.mzt@xxxxxxxxx> Date: Sat, 25 Apr 2015 19:52:37 +0200 Subject: libata: Ignore spurious PHY event on LPM policy change From: Gabriele Mazzotta <gabriele.mzt@xxxxxxxxx> commit 09c5b4803a80a5451d950d6a539d2eb311dc0fb1 upstream. When the LPM policy is set to ATA_LPM_MAX_POWER, the device might generate a spurious PHY event that cuases errors on the link. Ignore this event if it occured within 10s after the policy change. The timeout was chosen observing that on a Dell XPS13 9333 these spurious events can occur up to roughly 6s after the policy change. Link: http://lkml.kernel.org/g/3352987.ugV1Ipy7Z5@xps13 Signed-off-by: Gabriele Mazzotta <gabriele.mzt@xxxxxxxxx> Signed-off-by: Tejun Heo <tj@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/ata/libata-core.c | 15 ++++++++++++++- drivers/ata/libata-eh.c | 3 +++ include/linux/libata.h | 9 +++++++++ 3 files changed, 26 insertions(+), 1 deletion(-) --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -6814,8 +6814,21 @@ u32 ata_wait_register(struct ata_port *a */ bool sata_lpm_ignore_phy_events(struct ata_link *link) { + unsigned long lpm_timeout = link->last_lpm_change + + msecs_to_jiffies(ATA_TMOUT_SPURIOUS_PHY); + /* if LPM is enabled, PHYRDY doesn't mean anything */ - return !!(link->lpm_policy > ATA_LPM_MAX_POWER); + if (link->lpm_policy > ATA_LPM_MAX_POWER) + return true; + + /* ignore the first PHY event after the LPM policy changed + * as it is might be spurious + */ + if ((link->flags & ATA_LFLAG_CHANGED) && + time_before(jiffies, lpm_timeout)) + return true; + + return false; } EXPORT_SYMBOL_GPL(sata_lpm_ignore_phy_events); --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -3481,6 +3481,9 @@ static int ata_eh_set_lpm(struct ata_lin } } + link->last_lpm_change = jiffies; + link->flags |= ATA_LFLAG_CHANGED; + return 0; fail: --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -187,6 +187,7 @@ enum { ATA_LFLAG_SW_ACTIVITY = (1 << 7), /* keep activity stats */ ATA_LFLAG_NO_LPM = (1 << 8), /* disable LPM on this link */ ATA_LFLAG_RST_ONCE = (1 << 9), /* limit recovery to one reset */ + ATA_LFLAG_CHANGED = (1 << 10), /* LPM state changed on this link */ /* struct ata_port flags */ ATA_FLAG_SLAVE_POSS = (1 << 0), /* host supports slave dev */ @@ -289,6 +290,12 @@ enum { */ ATA_TMOUT_PMP_SRST_WAIT = 5000, + /* When the LPM policy is set to ATA_LPM_MAX_POWER, there might + * be a spurious PHY event, so ignore the first PHY event that + * occurs within 10s after the policy change. + */ + ATA_TMOUT_SPURIOUS_PHY = 10000, + /* ATA bus states */ BUS_UNKNOWN = 0, BUS_DMA = 1, @@ -736,6 +743,8 @@ struct ata_link { struct ata_eh_context eh_context; struct ata_device device[ATA_MAX_DEVICES]; + + unsigned long last_lpm_change; /* when last LPM change happened */ }; #define ATA_LINK_CLEAR_BEGIN offsetof(struct ata_link, active_tag) #define ATA_LINK_CLEAR_END offsetof(struct ata_link, device[0]) Patches currently in stable-queue which might be from gabriele.mzt@xxxxxxxxx are queue-3.10/libata-add-helper-to-determine-when-phy-events-should-be-ignored.patch queue-3.10/libata-ignore-spurious-phy-event-on-lpm-policy-change.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html