linux-kernel - Re: [PATCH v2 3/3] ata: ahci: Skip 200 ms debounce delay for AMD 300 Series Chipset SATA Controller

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <d9837420-1cbb-ed5e-7043-985d9eb9d065@opensource.wdc.com>
Date:   Wed, 23 Mar 2022 17:24:33 +0900
From:   Damien Le Moal <damien.lemoal@...nsource.wdc.com>
To:     Paul Menzel <pmenzel@...gen.mpg.de>,
        Mario Limonciello <Mario.Limonciello@....com>
Cc:     Hans de Goede <hdegoede@...hat.com>, linux-ide@...r.kernel.org,
        LKML <linux-kernel@...r.kernel.org>,
        Nehal-bakulchandra Shah <Nehal-bakulchandra.Shah@....com>
Subject: Re: [PATCH v2 3/3] ata: ahci: Skip 200 ms debounce delay for AMD 300
 Series Chipset SATA Controller

On 3/23/22 15:55, Paul Menzel wrote:
> Dear Damien,
> 
> 
> Am 23.03.22 um 06:01 schrieb Damien Le Moal:
>> On 3/22/22 06:51, Limonciello, Mario wrote:
>>> [Public]
>>>
>>>> -----Original Message-----
>>>> From: Paul Menzel <pmenzel@...gen.mpg.de>
>>>> Sent: Monday, March 21, 2022 16:25
> 
> […]
> 
>>> I seem to recall that we were talking about trying to drop the debounce delay for
>>> everything, weren't we?
>>>
>>> So perhaps it would be right to add a 4th patch in the series to do just that.  Then
>>> If this turns out to be problematic for anything other than the controllers in the
>>> series that you identified as not problematic then that 4th patch can potentially
>>> be reverted alone?
>>
>> Not quite everything :) But you are right, let's try to switch the default
>> to no delay. I will be posting patches today for that.
>>
>> Paul,
>>
>> With these patches, your patches are not necessary anymore as the AMD
>> chipset falls under the default no-delay.
> 
> I am all for improving the situation for all devices, but I am unable to 
> judge the regression potential of changing this, as it affects a lot of 
> devices. I guess it’d would go through the next tree, and hopefully the 
> company QA teams can give it a good spin. I hoped that my patches, as I 
> have tested them, and AMD will hopefully too, could go into the current 
> merge window.

Yes, correct, the plan is to get the generic series queued as soon as rc1
so that it can spend plenty of time in linux-next for people to test. That
will hopefully reduce the risk of breaking things in the field. Same for
the default LPM change.

With the default removal of the debounce delay, your patches addressing
only the AMD adapter are not needed anymore: this adapter will not have a
debounce delay unless the ATA_LFLAG_DEBOUNCE_DELAY flag is set.

> 
>> It would be nice if you can test though.
> 
> Of course, I am going to that either way.

Series posted with you on CC. Please test !

> 
> 
> Kind regards,
> 
> Paul


-- 
Damien Le Moal
Western Digital Research