libata: fix incorrect link online check during probe
PATCH 1/1 libata: fix incorrect link online check during probe
While trying to work around spurious detection retries for non-existent devices on slave links, commit 816ab89782ac139a8b65147cca990822bb7e8675 incorrectly added link offline check logic before ata_eh_thaw() was called. This means that if an occupied link goes down briefly at the time that offline check was performed, device class will be cleared to ATA_DEV_NONE and libata wouldn't retry thus failing detection of the device.
The offline check should be done after the port is thawed together with online check so that such link glitches can be detected by the interrupt handler and handled properly.
--
drivers/ata/libata-eh.c | 50 ++++++++++++++++++++++++++++++------------------ 1 file changed, 32 insertions(+), 18 deletions(-)
drivers/ata/libata-eh.c +32 -18
@@ -2667,14 +2667,14 @@ int ata_eh_reset(struct ata_link *link, int classify, dev->pio_mode =XFER_PIO_0 ; dev->flags &= ~ATA_DFLAG_SLEEPING ; -if (!ata_phys_link_offline (ata_dev_phys_link (dev))) { -/* apply class override */ -if (lflags &ATA_LFLAG_ASSUME_ATA ) - classes[dev->devno] =ATA_DEV_ATA ; -else if (lflags &ATA_LFLAG_ASSUME_SEMB ) - classes[dev->devno] =ATA_DEV_SEMB_UNSUP ; - }else - classes[dev->devno] =ATA_DEV_NONE ; +if (ata_phys_link_offline (ata_dev_phys_link (dev))) +continue ; + +/* apply class override */ +if (lflags &ATA_LFLAG_ASSUME_ATA ) + classes[dev->devno] =ATA_DEV_ATA ; +else if (lflags &ATA_LFLAG_ASSUME_SEMB ) + classes[dev->devno] =ATA_DEV_SEMB_UNSUP ; }/* record current link speed */
@@ -2713,34 +2713,48 @@ int ata_eh_reset(struct ata_link *link, int classify, ap->pflags &= ~ATA_PFLAG_EH_PENDING ;spin_unlock_irqrestore (link->ap->lock, flags); -/* Make sure onlineness and classification result correspond. +/* +* Make sure onlineness and classification result correspond. * Hotplug could have happened during reset and some * controllers fail to wait while a drive is spinning up after * being hotplugged causing misdetection. By cross checking -* link onlineness and classification result, those conditions -* can be reliably detected and retried. +* link on/offlineness and classification result, those +* conditions can be reliably detected and retried. */ nr_unknown =0 ;ata_for_each_dev (dev, link,ALL ) { -/* convert all ATA_DEV_UNKNOWN to ATA_DEV_NONE */ -if (classes[dev->devno] ==ATA_DEV_UNKNOWN ) { - classes[dev->devno] =ATA_DEV_NONE ; -if (ata_phys_link_online (ata_dev_phys_link (dev))) +if (ata_phys_link_online (ata_dev_phys_link (dev))) { +if (classes[dev->devno] ==ATA_DEV_UNKNOWN ) { +ata_dev_printk (dev,KERN_DEBUG ,"link online " +"but device misclassifed\n" ); + classes[dev->devno] =ATA_DEV_NONE ; nr_unknown++; + } + }else if (ata_phys_link_offline (ata_dev_phys_link (dev))) { +if (ata_class_enabled (classes[dev->devno])) +ata_dev_printk (dev,KERN_DEBUG ,"link offline, " +"clearing class %d to NONE\n" , + classes[dev->devno]); + classes[dev->devno] =ATA_DEV_NONE ; + }else if (classes[dev->devno] ==ATA_DEV_UNKNOWN ) { +ata_dev_printk (dev,KERN_DEBUG ,"link status unknown, " +"clearing UNKNOWN to NONE\n" ); + classes[dev->devno] =ATA_DEV_NONE ; } }if (classify && nr_unknown) {if (try < max_tries) {ata_link_printk (link,KERN_WARNING ,"link online but " -"device misclassified, retrying\n" ); +"%d devices misclassified, retrying\n" , + nr_unknown); failed_link = link; rc = -EAGAIN ; goto fail; }ata_link_printk (link,KERN_WARNING , -"link online but device misclassified, " -"device detection might fail\n" ); +"link online but %d devices misclassified, " +"device detection might fail\n" , nr_unknown); }/* reset successful, schedule revalidation */
Jeff Garzik
AppliedQuoted 12 lines · Tejun Heo
While trying to work around spurious detection retries for non-existent devices on slave links, commit
816ab89782ac139a8b65147cca990822bb7e8675incorrectly added link offline check logic beforeata_eh_thaw()was called. This means that if an occupied link goes down briefly at the time that offline check was performed, device class will be cleared toATA_DEV_NONEand libata wouldn't retry thus failing detection of the device.The offline check should be done after the port is thawed together with online check so that such link glitches can be detected by the interrupt handler and handled properly.
Quoted 6 lines
Signed-off-by Tejun Heo<[email protected]>Reported-by Tim Blechmann<[email protected]>--
drivers/ata/libata-eh.c | 50 ++++++++++++++++++++++++++++++------------------ 1 file changed, 32 insertions(+), 18 deletions(-)
applied. BTW, note your separator lost a dash... it should be three dashes (---).
Quoted 21 lines · Jeff Garzik
Quoted 8 lines · Tejun Heo
While trying to work around spurious detection retries for non-existent devices on slave links, commit
816ab89782ac139a8b65147cca990822bb7e8675incorrectly added link offline check logic beforeata_eh_thaw()was called. This means that if an occupied link goes down briefly at the time that offline check was performed, device class will be cleared toATA_DEV_NONEand libata wouldn't retry thus failing detection of the device.Quoted 11 lines
The offline check should be done after the port is thawed together with online check so that such link glitches can be detected by the interrupt handler and handled properly.
Signed-off-by Tejun Heo<[email protected]>Reported-by Tim Blechmann<[email protected]>Signature · 3 lines
drivers/ata/libata-eh.c | 50 ++++++++++++++++++++++++++++++------------------ 1 file changed, 32 insertions(+), 18 deletions(-)
Quoted 2 lines
applied. BTW, note your separator lost a dash... it should be three dashes (---).
Oops, sorry about that.
Signature · 1 line
tejun