linux-kernel - Re: [patch 17/24] x86/speculation: Move IBPB control out of switch

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <alpine.DEB.2.21.1811222328510.1665@nanos.tec.linutronix.de>
Date:   Thu, 22 Nov 2018 23:29:34 +0100 (CET)
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Ingo Molnar <mingo@...nel.org>
cc:     LKML <linux-kernel@...r.kernel.org>, x86@...nel.org,
        Peter Zijlstra <peterz@...radead.org>,
        Andy Lutomirski <luto@...nel.org>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        Jiri Kosina <jkosina@...e.cz>,
        Tom Lendacky <thomas.lendacky@....com>,
        Josh Poimboeuf <jpoimboe@...hat.com>,
        Andrea Arcangeli <aarcange@...hat.com>,
        David Woodhouse <dwmw@...zon.co.uk>,
        Andi Kleen <ak@...ux.intel.com>,
        Dave Hansen <dave.hansen@...el.com>,
        Casey Schaufler <casey.schaufler@...el.com>,
        Asit Mallick <asit.k.mallick@...el.com>,
        Arjan van de Ven <arjan@...ux.intel.com>,
        Jon Masters <jcm@...hat.com>,
        Waiman Long <longman9394@...il.com>,
        Greg KH <gregkh@...uxfoundation.org>,
        Dave Stewart <david.c.stewart@...el.com>,
        Kees Cook <keescook@...omium.org>
Subject: Re: [patch 17/24] x86/speculation: Move IBPB control out of
 switch_mm()

On Thu, 22 Nov 2018, Ingo Molnar wrote:
> * Thomas Gleixner <tglx@...utronix.de> wrote:
> >  	/*
> >  	 * Now maybe reload the debug registers and handle I/O bitmaps
> >  	 */
> > -	if (unlikely(task_thread_info(next_p)->flags & _TIF_WORK_CTXSW_NEXT ||
> > -		     task_thread_info(prev_p)->flags & _TIF_WORK_CTXSW_PREV))
> > +	if (unlikely(next_tif & _TIF_WORK_CTXSW_NEXT ||
> > +		     prev_tif & _TIF_WORK_CTXSW_PREV))
> >  		__switch_to_xtra(prev_p, next_p, tss);
> 
> Hm, the repetition between process_32.c and process_64.c is getting 
> stronger - could some of this be unified into process.c? (in later 
> patches)

Yes, for the price of an out of line call.

Thanks,

	tglx