On Mon, Sep 11, 2023 at 01:02:00PM +0900, Damien Le Moal wrote:
> 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@xxxxxxxxxxxxxxx
> Signed-off-by: Damien Le Moal <dlemoal@xxxxxxxxxx>
Tested-by: Chia-Lin Kao (AceLan) <acelan.kao@xxxxxxxxxxxxx>
