Hi Damien,
On Tue, 12 Sep 2023, Damien Le Moal wrote:
There is no direct device ancestry defined between an ata_device and
its scsi device which prevents the power management code from correctly
ordering suspend and resume operations. Create such ancestry with the
ata device as the parent to ensure that the scsi device (child) is
suspended before the ata device and that resume handles the ata device
before the scsi device.
The parent-child (supplier-consumer) relationship is established between
the ata_port (parent) and the scsi device (child) with the function
device_add_link(). The parent used is not the ata_device as the PM
operations are defined per port and the status of all devices connected
through that port is controlled from the port operations.
The device link is established with the new function
ata_scsi_dev_alloc(). This function is used to define the ->slave_alloc
callback of the scsi host template of most drivers.
Fixes: a19a93e4c6a9 ("scsi: core: pm: Rely on the device driver core for async power management")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Damien Le Moal <dlemoal@xxxxxxxxxx>
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>
Thanks for your patch, which is now commit 99626085d036ec32 ("ata:
libata-scsi: link ata port and scsi device") in libata/for-next.
This patch causes /dev/sda to disappear on Renesas Salvator-XS with
R-Car H3 ES2.0. Changes to dmesg before/after:
sata_rcar ee300000.sata: ignoring dependency for device, assuming no driver
scsi host0: sata_rcar
-ata1: SATA max UDMA/133 irq 184 lpm-pol 0
+ata1: SATA max UDMA/133 irq 179 lpm-pol 0
ata1: link resume succeeded after 1 retries
ata1: SATA link up 1.5 Gbps (SStatus 113 SControl 300)
ata1.00: ATA-7: Maxtor 6L160M0, BANC1G10, max UDMA/133
ata1.00: 320173056 sectors, multi 0: LBA48 NCQ (not used)
ata1.00: configured for UDMA/133
scsi 0:0:0:0: Direct-Access ATA Maxtor 6L160M0 1G10 PQ: 0 ANSI: 5
-sd 0:0:0:0: [sda] 320173056 512-byte logical blocks: (164 GB/153 GiB)
-sd 0:0:0:0: [sda] Write Protect is off
-sd 0:0:0:0: [sda] Mode Sense: 00 3a 00 00
-sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
-sd 0:0:0:0: [sda] Preferred minimum I/O size 512 bytes
- sda: sda1
-sd 0:0:0:0: [sda] Attached SCSI disk
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
