linux-kernel - Re: 2.6.37.1 s2disk regression (TPM)

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: <4D62E221.7010104@linux.vnet.ibm.com>
Date:	Mon, 21 Feb 2011 19:07:29 -0300
From:	Rajiv Andrade <srajiv@...ux.vnet.ibm.com>
To:	Jiri Slaby <jirislaby@...il.com>
CC:	Stefan Berger <stefanb@...ux.vnet.ibm.com>,
	"Rafael J. Wysocki" <rjw@...k.pl>,
	linux-pm <linux-pm@...ts.linux-foundation.org>,
	stable@...nel.org,
	Linux kernel mailing list <linux-kernel@...r.kernel.org>,
	debora@...ux.vnet.ibm.com,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	preining@...ic.at
Subject: Re: 2.6.37.1 s2disk regression (TPM)

On 02/21/2011 06:44 PM, Jiri Slaby wrote:
> On 02/21/2011 10:29 PM, Stefan Berger wrote:
>> On 02/21/2011 03:39 PM, Jiri Slaby wrote:
>>> On 02/21/2011 06:12 PM, Rajiv Andrade wrote:
>>>> On 02/21/2011 01:34 PM, Jiri Slaby wrote:
>>>>> There has to be another problem which caused my regression. And
>>>>> since it
>>>>> reports "Operation Timed out", the former default timeout values worked
>>>>> for me, the ones read from TPM do not.
>>>> Yes, it's highly due inconsistent timeout values reported by the TPM as
>>>> I mentioned, my working timeouts are:
>>>> 3020000 4510000 181000000
>>> 1000000 2000 150000
>>>
>>> Actually the first one from HW is 1. This is one is HZ after correction
>>> in get_timeout. So perhaps it is in ms, yes.
>> Following the specs, the timeouts are supposed to be in microseconds and
>> ascending order for short, medium and long duration. Of course, if the
>> device returns wrong timeouts, the command isn't going to succeed,
>> failing the suspend in this case. Nevertheless, I think we need the
>> patch I put in but at the same time we'll need a work-around for devices
>> like this.
> Yes, the patch is correct per se. But as it breaks bunch of machines it
> cannot go in now. The rule is no regressions.
>
> After you have the workaround it should go into the next rc1 after that.
> Do you plan to add a dmi-based quirk? Or, IOW do you want me to attach
> dmidecode output? Or are you going to base it solely on TPM
> manufacturer/version
It's more reliable to base the workaround on the values themselves, instead of the TPM's ID, since
we don't know whether other models will behave similarly.

It should be fine then to extend the existing workaround for short timeouts to the medium and long ones.

Rajiv

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/