Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Sun, 7 Feb 2021 16:45:40 -0600
From:   Josh Poimboeuf <jpoimboe@redhat.com>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Borislav Petkov <bp@suse.de>, Dave Hansen <dave.hansen@intel.com>,
        Steven Rostedt <rostedt@goodmis.org>, x86-ml <x86@kernel.org>,
        lkml <linux-kernel@vger.kernel.org>,
        Alexei Starovoitov <ast@kernel.org>
Subject: Re: [GIT PULL] x86/urgent for v5.11-rc7
Message-ID: <20210207224540.ercf5657pftibyaw@treble>
References: <20210207104022.GA32127@zn.tnic>
 <CAHk-=widXSyJ8W3vRrqO-zNP12A+odxg2J2_-oOUskz33wtfqA@mail.gmail.com>
 <20210207175814.GF32127@zn.tnic>
 <CAHk-=wi5z9S7x94SKYNj6qSHBqz+OD76GW=MDzo-KN2Fzm-V4Q@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <CAHk-=wi5z9S7x94SKYNj6qSHBqz+OD76GW=MDzo-KN2Fzm-V4Q@mail.gmail.com>
Precedence: bulk

On Sun, Feb 07, 2021 at 10:15:49AM -0800, Linus Torvalds wrote:
> On Sun, Feb 7, 2021 at 9:58 AM Borislav Petkov <bp@suse.de> wrote:
> >
> > It probably is an item on some Intel manager's to-enable list. So far,
> > the CET enablement concentrates only on userspace but dhansen might know
> > more about future plans. CCed.
> 
> I think the new Ryzen 5000 series also supports CET, but I don't have
> any machines to check.
> 
> Hopefully somebody ends up with hardware that supports it and a urge
> to try to make it work in kernel land too.
> 
> I do suspect involved people should start thinking about how they want
> to deal with functions starting with
> 
>         endbr64
>         call __fentry__
> 
> instead of the call being at the very top of the function.

FWIW, objtool's already fine with it (otherwise we would have discovered
the need to disable fcf-protection much sooner).

-- 
Josh