Re: [PATCH] scsi: sd: fix sd shutdown to issue START STOP UNIT command appropriately

Bart Van Assche
2025-07-24T20:46:32Z

On 7/24/25 1:38 PM, Salomon Dushimirimana wrote:
> Commit aa3998dbeb3a ("ata: libata-scsi: Disable scsi device
> manage_system_start_stop") enabled libata EH to manage device power mode
> trasitions for system suspend/resume and removed the flag from
> ata_scsi_dev_config. However, since the sd_shutdown() function still
> relies on the manage_system_start_stop flag, a spin-down command is not
> issued to the disk with command "echo 1 > /sys/block/sdb/device/delete"
>
> sd_shutdown() can be called for both system/runtime start stop
> operations, so utilize the manage_run_time_start_stop flag set in the
> ata_scsi_dev_config and issue a spin-down command during disk removal
> when the system is running. This is in addition to when the system is
> powering off and manage_shutdown flag is set. The
> manage_system_start_stop flag will still be used for drivers that still
> set the flag.
>
> Signed-off-by: Salomon Dushimirimana <salomondush@google.com>
> ---
> drivers/scsi/sd.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
> index eeaa6af294b81..282000c761f8e 100644
> --- a/drivers/scsi/sd.c
> +++ b/drivers/scsi/sd.c
> @@ -4173,7 +4173,9 @@ static void sd_shutdown(struct device *dev)
> if ((system_state != SYSTEM_RESTART &&
> sdkp->device->manage_system_start_stop) ||
> (system_state == SYSTEM_POWER_OFF &&
> - sdkp->device->manage_shutdown)) {
> + sdkp->device->manage_shutdown) ||
> + (system_state == SYSTEM_RUNNING &&
> + sdkp->device->manage_runtime_start_stop)) {
> sd_printk(KERN_NOTICE, sdkp, "Stopping disk\n");
> sd_start_stop_device(sdkp, 0);
> }

A Fixes: tag is missing.

manage_runtime_start_stop is for runtime power management.
/sys/block/*/device/delete is not related to runtime power management.
Isn't manage_system_start_stop more appropriate here than
manage_runtime_start_stop? Shouldn't sd_shutdown() calls triggered by
writing into /sys/block/*/device/delete already be covered by this
test: system_state != SYSTEM_RESTART &&
sdkp->device->manage_system_start_stop?

Thanks,

Bart.