amd64/135014: [padlock] Using padlock(4) in 8-current triggers "fpudna in kernel mode!" warnings

[Andriy Gapon]

The following reply was made to PR amd64/135014; it has been noted by GNATS.

From: Andriy Gapon <avg at icyb.net.ua>
To: bug-followup at FreeBSD.org, mark at legios.org
Cc:  
Subject: Re: amd64/135014: [padlock] Using padlock(4) in 8-current triggers
 "fpudna in kernel mode!" warnings
Date: Tue, 23 Mar 2010 12:13:23 +0200

 Some potentially useful info on this issue, mostly for the reference.
 
 Here's how Linux does it:
 http://lxr.linux.no/#linux+v2.6.33/drivers/crypto/padlock-aes.c#L182
 It seems that they claim that padlock instructions do not actually use XMM
 registers, but they are sensitive about TS bit.
 
 Also, kib@ has patch that allows to actually use XMM registers in kernel within
 a limited scope:
 http://docs.freebsd.org/cgi/getmsg.cgi?fetch=2304+0+current/freebsd-amd64
 
 -- 
 Andriy Gapon