From: Andi Kleen <andi@firstfloor.org>
To: Agner Fog <agner@agner.org>
Cc: Arjan van de Ven <arjan@infradead.org>,
"H. Peter Anvin" <hpa@zytor.com>,
linux-kernel@vger.kernel.org
Subject: Re: ABI change for device drivers using future AVX instruction set
Date: Sat, 28 Jun 2008 13:47:43 +0200 [thread overview]
Message-ID: <87myl5pyqo.fsf@basil.nowhere.org> (raw)
In-Reply-To: <4865F0DA.2050906@agner.org> (Agner Fog's message of "Sat, 28 Jun 2008 10:05:46 +0200")
Agner Fog <agner@agner.org> writes:
I explained it earlier, but you didn't seem to have understood it.
Here's it again in a simpler form:
If a x86 device driver doesn't use the standard kernel interfaces
for saving/restoring extended state (kernel_fpu_begin/end) it will die.
That is because Linux uses lazy FPU saving by default and when the lazy FPU exception
hits kernel code it will crash because that's not allowed.
And the standard interfaces are going to handle all extended state supported
by the kernel. Full XSAVE support should be there for 2.6.27.
Pretty much the whole problem you describe in your original email doesn't
apply to Linux because of that.
-Andi
next prev parent reply other threads:[~2008-06-28 11:47 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-06-25 15:32 ABI change for device drivers using future AVX instruction set Agner Fog
2008-06-25 16:22 ` Arjan van de Ven
2008-06-25 19:54 ` Agner Fog
2008-06-25 20:09 ` Arjan van de Ven
2008-06-26 1:11 ` H. Peter Anvin
2008-06-27 11:31 ` Agner Fog
2008-06-27 14:22 ` Arjan van de Ven
2008-06-28 8:05 ` Agner Fog
2008-06-28 8:10 ` David Miller
2008-06-28 11:47 ` Andi Kleen [this message]
2008-06-28 15:09 ` Agner Fog
2008-06-28 15:44 ` Helge Hafting
2008-06-28 20:02 ` Andi Kleen
2008-06-29 11:33 ` Avi Kivity
2008-06-29 12:21 ` Andi Kleen
2008-06-29 12:31 ` Avi Kivity
2008-06-29 13:07 ` Andi Kleen
2008-06-29 13:18 ` Avi Kivity
2008-06-29 13:23 ` Andi Kleen
2008-06-29 13:29 ` Avi Kivity
2008-06-29 22:08 ` H. Peter Anvin
2008-06-29 12:29 ` Alan Cox
2008-07-01 15:30 ` Arjan van de Ven
2008-06-25 20:14 ` Alan Cox
2008-06-26 14:01 ` Andi Kleen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87myl5pyqo.fsf@basil.nowhere.org \
--to=andi@firstfloor.org \
--cc=agner@agner.org \
--cc=arjan@infradead.org \
--cc=hpa@zytor.com \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox