From eec7e1c16d2b65e38137686dd9b7e102c2150905 Mon Sep 17 00:00:00 2001 From: Alexey Asemov Date: Tue, 15 Jul 2014 10:28:42 +0400 Subject: [PATCH] libata: EH should handle AMNF error condition as a media error libata-eh.c should handle AMNF error condition (error byte bit 0, usually code 0x01) in libata-eh.c along with UNC as a media error so SCSI stack can handle it properly (translation code 0x01 is already present in libata-scsi.c) but was never passed down due to lack of handling in EH. While using linux-based machine (AMD 6550M-based notebook, PCI IDs for the controller are 1022:7801 subsys 1025:059d) and ddrescue to salvage data from failing hard drive (WD7500BPVT 2.5" 750G SATA2), I've found that pure AMNF 0x01 error code generates generic "device error" that is retried several times by SCSI stack instead of "media error" that is passed up to software. So we may assume deprecated AMNF error code is surely not dead yet, and it's better for it to be handled properly. As we may see it is used by modern enough devices, and used properly: drive returned AMNF only when IDs for track cannot be read completely due to dying head or positioning, otherwise it returned UNC(orrectables). Not handling it causes wrong generic error code ("device error") reporting down the stack, can damage failing drives further because of excessive retries, and slows salvaging down a lot. Also, there is handling code in libata-scsi.c for 0x01 AMNF error already. https://bugzilla.kernel.org/show_bug.cgi?id=80031 tj: Shortened $SUBJ and moved its content to the first paragraph. Signed-off-by: Alexey Asemov Signed-off-by: Tejun Heo --- drivers/ata/libata-eh.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index 6760fc4e85b8..dad83df555c4 100644 --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -1811,7 +1811,7 @@ static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc, case ATA_DEV_ATA: if (err & ATA_ICRC) qc->err_mask |= AC_ERR_ATA_BUS; - if (err & ATA_UNC) + if (err & (ATA_UNC | ATA_AMNF)) qc->err_mask |= AC_ERR_MEDIA; if (err & ATA_IDNF) qc->err_mask |= AC_ERR_INVALID; @@ -2556,11 +2556,12 @@ static void ata_eh_link_report(struct ata_link *link) } if (cmd->command != ATA_CMD_PACKET && - (res->feature & (ATA_ICRC | ATA_UNC | ATA_IDNF | - ATA_ABORTED))) - ata_dev_err(qc->dev, "error: { %s%s%s%s}\n", + (res->feature & (ATA_ICRC | ATA_UNC | ATA_AMNF | + ATA_IDNF | ATA_ABORTED))) + ata_dev_err(qc->dev, "error: { %s%s%s%s%s}\n", res->feature & ATA_ICRC ? "ICRC " : "", res->feature & ATA_UNC ? "UNC " : "", + res->feature & ATA_AMNF ? "AMNF " : "", res->feature & ATA_IDNF ? "IDNF " : "", res->feature & ATA_ABORTED ? "ABRT " : ""); #endif -- 2.20.1