On 9/14/23 16:08, Geert Uytterhoeven wrote:
> Hi Damien,
>
> On Wed, Sep 13, 2023 at 12:27 PM Geert Uytterhoeven
> <geert@xxxxxxxxxxxxxx> wrote:
>> 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
>
> I see the same issue on SH/Landisk, which has CompactFLASH:
>
> -ata1: PATA max PIO0 ioport cmd 0xc0023040 ctl 0xc002302c irq 26
> +ata1: PATA max PIO0 ioport cmd 0xc0023040 ctl 0xc002302c irq 26 lpm-pol 0
> ata1.00: CFA: TS8GCF133, 20171204, max UDMA/100
> ata1.00: 15662304 sectors, multi 0: LBA48
> ata1.00: configured for PIO
> scsi 0:0:0:0: Direct-Access ATA TS8GCF133 1204
> PQ: 0 ANSI: 5
> -sd 0:0:0:0: [sda] 15662304 512-byte logical blocks: (8.02 GB/7.47 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 sda2 sda3
> -sd 0:0:0:0: [sda] Attached SCSI removable disk
>
> and m68k/ARAnyM:
>
> atari-falcon-ide atari-falcon-ide: Atari Falcon and Q40/Q60 PATA controller
> scsi host0: pata_falcon
> ata1: PATA max PIO4 cmd fff00000 ctl fff00038 data fff00000 no
> IRQ, using PIO polling
> ata1.00: ATA-2: Sarge m68k, , max PIO2
> ata1.00: 2118816 sectors, multi 0: LBA
> ata1.00: configured for PIO
> scsi 0:0:0:0: Direct-Access ATA Sarge m68k n/a
> PQ: 0 ANSI: 5
> -sd 0:0:0:0: [sda] 2118816 512-byte logical blocks: (1.08 GB/1.01 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: disabled, read cache: enabled,
> doesn't support DPO or FUA
> -sd 0:0:0:0: [sda] Preferred minimum I/O size 512 bytes
> - sda: AHDI sda1 sda2
> -sd 0:0:0:0: [sda] Attached SCSI disk
>
> Reverting 99626085d036ec32 fixes the issue.
Yes. I can confirm this. I can recreate the issue, because I have a major
screw-up with that patch: the device_link_add() done in the new ->slave_alloc
operation for the scsi_host_template for the driver was in fact NOT set for
AHCI. So all my testing confirming that suspend/resume is OK was done *without*
that device link being created... That is embarrassing :)
The sata_rcar driver does get that slave_alloc method set through ATA_BASE_SHT()
-> ATA_SUBBASE_SHT(), and you get the problem. If I fix AHCI_SHT() macro to set
slave_alloc, I do get the issue as well: no scsi disk device is created after
the port scan. No clue why.
And I also now have no clue how suddenly the suspend/resume operations get
magically ordered correctly... I could recreate various issues before the
patches in for-6.7.
So going back to the beginning to sort things out. I probably "inadvertently"
fixed the issues with another change that has implications I am not seeing.
Will get back to you ASAP.
>
> Gr{oetje,eeting}s,
>
> Geert
>
--
Damien Le Moal
Western Digital Research
