On Mon, Jul 07, 2014 at 05:46:35PM +0200, Peter Zijlstra wrote: > On Mon, Jul 07, 2014 at 01:57:16PM +0000, Liang, Kan wrote: > > > > This doesn't work, e.g. hardware debuggers can take over at any time. > > > > > > Tough cookies. Hardware debuggers get to deal with whatever crap they > > > cause. > > > > If so, I think I may discard this patch (2/3). I will resubmit the > > other two patches as a patch set to only handle the KVM issue we > > found. It checks the access of LBR and extra MSRs at the > > initialization time and set the flags. So we just need to check the > > flags at runtime and avoid the protection by _safe(). > > Right. > > > For Intel PT and LBR handling, since the PT codes haven't been > > integrated yet, I will try to implement another patch later. The > > patch will add flags for LBR and PT. When enabling PT, it checks LBR > > flag and update the PT flag. When enabling LBR, it checks PT flag and > > update the LBR flag. When disabling LBR/PT, we just update the related > > flags. we don't need to add _safe or extra rmsr in fast path. > > Yeah, should be part of the PT patches. > > > How do you think? > > With my brain, much like all primates :-) Also, teach your mailer to wrap text at 78 chars or so.
Attachment:
pgp4WhnHed4Pt.pgp
Description: PGP signature
