Date: Sun, 6 Mar 2016 19:01:43 +0100
From: Borislav Petkov <bp@alien8.de>
To: Andy Lutomirski <luto@amacapital.net>
Cc: Brian Gerst <brgerst@gmail.com>, Andy Lutomirski <luto@kernel.org>,
        the arch/x86 maintainers <x86@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Oleg Nesterov <oleg@redhat.com>,
        Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH v2 07/10] x86/entry: Vastly simplify SYSENTER TF handling
Message-ID: <20160306180143.GB6902@pd.tnic>
References: <cover.1457243356.git.luto@kernel.org>
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 <20160306165546.GA6902@pd.tnic>
 <CAMzpN2gPp1GVP_u8_j-y5njY7m=vRc==_UjsH7d76rOcBwMDOw@mail.gmail.com>
 <CALCETrV32APYgOe7a4jOSu8p2siu28XQ+mFqrzxudceFkQmk7w@mail.gmail.com>
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On Sun, Mar 06, 2016 at 09:36:42AM -0800, Andy Lutomirski wrote:
> > ALTERNATIVE "movl TSS_sysenter_sp0(%esp), %esp", "addl $5*4, %esp",
> > X86_FEATURE_XENPV
> 
> That might work.

Yap, and as we said on IRC, KALLSYMS can be off - even if it is "if
EXPERT" so we need to think of a better way to compute start address and
size of entry_SYSENTER_32 and the _compat one.

We probably could reuse some of the ELF parsing machinery of relocs.c or
so...

-- 
Regards/Gruss,
    Boris.

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