linux-kernel - Re: Kernel oops with 2.6.26, padlock and ipsec: probably problem with fpu state changes

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 for Android: free password hash cracker in your pocket

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

Date:	Tue, 12 Aug 2008 20:02:13 +0800
From:	Herbert Xu <herbert@...dor.apana.org.au>
To:	Wolfgang Walter <wolfgang.walter@...m.de>
Cc:	Suresh Siddha <suresh.b.siddha@...el.com>,
	"H. Peter Anvin" <hpa@...or.com>,
	"netdev@...r.kernel.org" <netdev@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Ingo Molnar <mingo@...e.hu>,
	"viro@...IV.linux.org.uk" <viro@...iv.linux.org.uk>,
	"vegard.nossum@...il.com" <vegard.nossum@...il.com>
Subject: Re: Kernel oops with 2.6.26, padlock and ipsec: probably problem with fpu state changes

On Tue, Aug 12, 2008 at 01:43:22PM +0200, Wolfgang Walter wrote:
>
> * Works fine, machine is up since 61 minutes.

Thanks a lot for testing this Wolfgang!

> * Performance:
> 
> Routing performance over esp-tunnels seems unchanged here compared to 2.6.25
> (this was also the case with the "kernel_fpu_begin" patch).
> 
> tcrypt mode=200 shows exactly the same performance penalty compared to 2.6.25
> as the "kernel_fpu_begin" patch.

That's not surprising since tcrypt runs with BH off so it'll
do pretty much the same thing as before.  This also shows that
reading CR0 doesn't impose any extra overhead compared to what
was done in kernel_fpu_begin.

Cheers,
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@...dor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
--
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/