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From: Vitaly Kuznetsov <vkuznets@redhat.com>
To: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: x86@kernel.org, Juergen Gross <jgross@suse.com>,
        Rusty Russell <rusty@rustcorp.com.au>, xen-devel@lists.xenproject.org,
        Peter Zijlstra <peterz@infradead.org>, Jiri Slaby <jslaby@suse.cz>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Mike Galbraith <efault@gmx.de>, linux-kernel@vger.kernel.org,
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        Chris Wright <chrisw@sous-sol.org>,
        Thomas Gleixner <tglx@linutronix.de>,
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        Borislav Petkov <bp@alien8.de>, live-patching@vger.kernel.org,
        Alok Kataria <akataria@vmware.com>,
        virtualization@lists.linux-foundation.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Ingo Molnar <mingo@kernel.org>
Subject: Re: [Xen-devel] [PATCH 00/13] x86/paravirt: Make pv ops code generation more closely match reality
References: <cover.1507128293.git.jpoimboe@redhat.com>
Date: Fri, 06 Oct 2017 09:35:16 +0200
In-Reply-To: <cover.1507128293.git.jpoimboe@redhat.com> (Josh Poimboeuf's
        message of "Wed, 4 Oct 2017 10:58:21 -0500")
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Josh Poimboeuf <jpoimboe@redhat.com> writes:

> - For the most common runtime cases (everything except Xen and vSMP),
>   vmlinux disassembly now matches what the actual runtime code looks
>   like.  This improves debuggability and kernel developer sanity (a
>   precious resource).
>
> ...
>
> - It's hopefully a first step in simplifying paravirt patching by
>   getting rid of .parainstructions, pv ops, and apply_paravirt()
>   completely.  (I think Xen can be changed to set CPU feature bits to
>   specify which ops it needs during early boot, then those ops can be
>   patched in using early alternatives.)

JFYI starting 4.14 Xen PV is not the only user of pv_mmu_ops, Hyper-V
uses it for TLB shootdown now.

-- 
  Vitaly