4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Damien Le Moal dlemoal@kernel.org
commit 84d76529c650f887f1e18caee72d6f0589e1baf9 upstream.
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.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/ata/libata-core.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-)
--- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -6750,11 +6750,30 @@ static void ata_port_detach(struct ata_p if (!ap->ops->error_handler) goto skip_eh;
- /* 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);