From: Matt Fleming <matt-HNK1S37rvNbeXh+fF434Mdi2O/JbrIOy@public.gmane.org>
To: Seiji Aguchi <seiji.aguchi-7rDLJAbr9SE@public.gmane.org>
Cc: Matthew Garrett <mjg59-1xO5oi07KQx4cg9Nei1l7Q@public.gmane.org>,
Matt Fleming
<matt.fleming-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>,
Ben Hutchings <ben-/+tVBieCtBitmTQ+vhA3Yw@public.gmane.org>,
Josh Boyer <jwboyer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>,
"stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
<stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
"linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
<linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
Seth Forshee
<seth.forshee-Z7WLFzj8eWMS+FvcfC7Uqw@public.gmane.org>
Subject: Re: efi: be more paranoid about available space when creating variables
Date: Wed, 27 Mar 2013 09:10:42 +0000 [thread overview]
Message-ID: <5152B792.1070104@console-pimps.org> (raw)
In-Reply-To: <A5ED84D3BB3A384992CBB9C77DEDA4D41AF79528-ohthHghroY0jroPwUH3sq+6wyyQG6/Uh@public.gmane.org>
On 26/03/13 23:33, Seiji Aguchi wrote:
> If we can calculate the size of available variables by ourselves,
> we don't need to call QueryVariableInfo().
> It makes efivars robust against buggy firmwares.
> Also, this patch actually fixes a serious bug, failing boot up.
>
> In theory, QueryVariableInfo() should return accurate values to kernel.
> But, it doesn't in practice.
Exactly and this patch is *still* relying on the output of
QueryVariableInfo(). I doubt DataSize will be accurate everywhere either.
> I think creating blacklist will be like playing whac-a-mole, because
> we can't anticipate how many buggy firmwares will appear in the future.
You wouldn't need to reimplement the workaround for every broken
machine, you just add the machine's identifiers to the list. And no, we
can't anticipate the firmware bugs we'll see in the future which is why
we need to solve this on a case-by-case basis.
--
Matt Fleming, Intel Open Source Technology Center
prev parent reply other threads:[~2013-03-27 9:10 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1364004995.3728.76.camel@deadeye.wl.decadent.org.uk>
[not found] ` <1364010441.3728.82.camel@deadeye.wl.decadent.org.uk>
[not found] ` <1364010441.3728.82.camel-nDn/Rdv9kqW9Jme8/bJn5UCKIB8iOfG2tUK59QYPAWc@public.gmane.org>
2013-03-23 20:24 ` efi: be more paranoid about available space when creating variables Fleming, Matt
2013-03-23 20:32 ` Matthew Garrett
[not found] ` <1364070731.2553.47.camel-tCUS0Eywp2Pehftex57rkxo58HMYffqeLoYNBG0abjxeoWH0uzbU5w@public.gmane.org>
2013-03-23 22:50 ` Matt Fleming
[not found] ` <514E31B0.4030305-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
2013-03-26 3:56 ` Matthew Garrett
2013-03-26 4:31 ` Lingzhu Xiang
[not found] ` <5151248F.2010303-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2013-03-26 4:34 ` Ben Hutchings
2013-03-26 4:35 ` Matthew Garrett
[not found] ` <20130326035600.GA6209-1xO5oi07KQx4cg9Nei1l7Q@public.gmane.org>
2013-03-26 7:40 ` Lingzhu Xiang
2013-04-01 15:13 ` [PATCH 1/2] efi: Determine how much space is used by boot services-only variables Matthew Garrett
[not found] ` <1364829240-26475-1-git-send-email-matthew.garrett-05XSO3Yj/JvQT0dZR+AlfA@public.gmane.org>
2013-04-01 15:14 ` [PATCH 2/2] efi: Distinguish between "remaining space" and actually used space Matthew Garrett
[not found] ` <1364829240-26475-2-git-send-email-matthew.garrett-05XSO3Yj/JvQT0dZR+AlfA@public.gmane.org>
2013-04-01 15:50 ` Ben Hutchings
2013-04-03 13:11 ` Matt Fleming
[not found] ` <515C2A86.6070606-HNK1S37rvNbeXh+fF434Mdi2O/JbrIOy@public.gmane.org>
2013-04-03 13:48 ` Matthew Garrett
2013-04-03 17:12 ` Matt Fleming
[not found] ` <515C62E6.1070004-HNK1S37rvNbeXh+fF434Mdi2O/JbrIOy@public.gmane.org>
2013-04-03 17:20 ` Matthew Garrett
2013-04-01 15:42 ` [PATCH 1/2] efi: Determine how much space is used by boot services-only variables Ben Hutchings
2013-04-03 13:09 ` Matt Fleming
[not found] ` <515C29EE.8050008-HNK1S37rvNbeXh+fF434Mdi2O/JbrIOy@public.gmane.org>
2013-04-03 13:42 ` Matthew Garrett
2013-03-26 10:37 ` efi: be more paranoid about available space when creating variables Matt Fleming
2013-03-26 15:43 ` Matthew Garrett
[not found] ` <20130326154359.GA20530-1xO5oi07KQx4cg9Nei1l7Q@public.gmane.org>
2013-03-27 9:09 ` Matt Fleming
[not found] ` <5152B75B.5080305-HNK1S37rvNbeXh+fF434Mdi2O/JbrIOy@public.gmane.org>
2013-04-01 6:31 ` Ben Hutchings
2013-03-26 23:33 ` Seiji Aguchi
[not found] ` <A5ED84D3BB3A384992CBB9C77DEDA4D41AF79528-ohthHghroY0jroPwUH3sq+6wyyQG6/Uh@public.gmane.org>
2013-03-27 9:10 ` Matt Fleming [this message]
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