| Message ID | 20230923002932.1082348-3-dlemoal@kernel.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Fix libata suspend/resume handling and code cleanup | expand |
On 9/22/23 17:29, Damien Le Moal wrote: > Also delete the WAR_ON() call checking that the ATA_PFLAG_UNLOADING flag > was cleared as that is done without holding the port lock. Hmm ... I don't see any WARN_ON() statement being removed by this patch? > - /* tell EH we're leaving & flush EH */ > + /* Wait for any ongoing EH */ > + ata_port_wait_eh(ap); > + > + mutex_lock(&ap->scsi_scan_mutex); > spin_lock_irqsave(ap->lock, flags); > + > + /* Remove scsi devices */ > + ata_for_each_link(link, ap, HOST_FIRST) { > + ata_for_each_dev(dev, link, ALL) { > + if (dev->sdev) { > + spin_unlock_irqrestore(ap->lock, flags); > + scsi_remove_device(dev->sdev); > + spin_lock_irqsave(ap->lock, flags); > + dev->sdev = NULL; > + } > + } > + } Can the lists ata_for_each_link() and ata_for_each_dev() iterate over change while ap->lock is unlocked? If not, does this perhaps have to be explained in a comment? If these lists can be changed, should these lists perhaps be examined from the start after every unlock of ap->lock? Thanks, Bart.
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 732f3d0b4fd9..8e35afe5e560 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -5948,11 +5948,30 @@ static void ata_port_detach(struct ata_port *ap) struct ata_link *link; struct ata_device *dev; - /* tell EH we're leaving & flush EH */ + /* Wait for any ongoing EH */ + ata_port_wait_eh(ap); + + mutex_lock(&ap->scsi_scan_mutex); spin_lock_irqsave(ap->lock, flags); + + /* Remove scsi devices */ + ata_for_each_link(link, ap, HOST_FIRST) { + ata_for_each_dev(dev, link, ALL) { + if (dev->sdev) { + spin_unlock_irqrestore(ap->lock, flags); + scsi_remove_device(dev->sdev); + spin_lock_irqsave(ap->lock, flags); + dev->sdev = NULL; + } + } + } + + /* Tell EH to disable all devices */ ap->pflags |= ATA_PFLAG_UNLOADING; ata_port_schedule_eh(ap); + spin_unlock_irqrestore(ap->lock, flags); + mutex_unlock(&ap->scsi_scan_mutex); /* wait till EH commits suicide */ ata_port_wait_eh(ap);
Whenever an ATA adapter driver is removed (e.g. rmmod), ata_port_detach() is called repeatedly for all the adapter ports to remove (unload) the devices attached to the port and delete the port device itself. Removing of devices is done using libata EH with the ATA_PFLAG_UNLOADING port flag set. This causes libata EH to execute ata_eh_unload() which disables all devices attached to the port. ata_port_detach() finishes by calling scsi_remove_host() to remove the scsi host associated with the port. This function will trigger the removal of all scsi devices attached to the host and in the case of disks, calls to sd_shutdown() which will flush the device write cache and stop the device. However, given that the devices were already disabled by ata_eh_unload(), the synchronize write cache command and start stop unit commands fail. E.g. running "rmmod ahci" with first removing sd_mod results in error messages like: ata13.00: disable device sd 0:0:0:0: [sda] Synchronizing SCSI cache sd 0:0:0:0: [sda] Synchronize Cache(10) failed: Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK sd 0:0:0:0: [sda] Stopping disk sd 0:0:0:0: [sda] Start/Stop Unit failed: Result: hostbyte=DID_BAD_TARGET driverbyte=DRIVER_OK Fix this by removing all scsi devices of the ata devices connected to the port before scheduling libata EH to disable the ATA devices. Also delete the WAR_ON() call checking that the ATA_PFLAG_UNLOADING flag was cleared as that is done without holding the port lock. Fixes: 720ba12620ee ("[PATCH] libata-hp: update unload-unplug") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com> Tested-by: Chia-Lin Kao (AceLan) <acelan.kao@canonical.com> Tested-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> --- drivers/ata/libata-core.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-)