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From:   Nadav Amit <namit@vmware.com>
To:     Juergen Gross <jgross@suse.com>,
        Hou Wenlong <houwenlong.hwl@antgroup.com>
CC:     kernel list <linux-kernel@vger.kernel.org>,
        Thomas Garnier <thgarnie@chromium.org>,
        Lai Jiangshan <jiangshan.ljs@antgroup.com>,
        Kees Cook <keescook@chromium.org>,
        "srivatsa@csail.mit.edu" <srivatsa@csail.mit.edu>,
        Alexey Makhalov <amakhalov@vmware.com>,
        Pv-drivers <Pv-drivers@vmware.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        X86 ML <x86@kernel.org>, "H. Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Song Liu <song@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
        "virtualization@lists.linux-foundation.org" 
        <virtualization@lists.linux-foundation.org>
Subject: Re: [PATCH RFC 13/43] x86/paravirt: Use relative reference for
 original instruction
Thread-Topic: [PATCH RFC 13/43] x86/paravirt: Use relative reference for
 original instruction
Thread-Index: AQHZebcsO0UIioi4Kkq/QcVuF28Wwa9147CAgAYY4IA=
Date:   Mon, 5 Jun 2023 06:40:54 +0000
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> On Jun 1, 2023, at 2:29 AM, Juergen Gross <jgross@suse.com> wrote:
>=20
> On 28.04.23 11:50, Hou Wenlong wrote:
>> Similar to the alternative patching, use relative reference for original
>> instruction rather than absolute one, which saves 8 bytes for one entry
>> on x86_64.  And it could generate R_X86_64_PC32 relocation instead of
>> R_X86_64_64 relocation, which also reduces relocation metadata on
>> relocatable builds. And the alignment could be hard coded to be 4 now.
>> Signed-off-by: Hou Wenlong <houwenlong.hwl@antgroup.com>
>> Cc: Thomas Garnier <thgarnie@chromium.org>
>> Cc: Lai Jiangshan <jiangshan.ljs@antgroup.com>
>> Cc: Kees Cook <keescook@chromium.org>
>=20
> Reviewed-by: Juergen Gross <jgross@suse.com>
>=20
> I think this patch should be taken even without the series.

It looks good to me, I am just not sure what the alignment is needed
at all.

Why not to make the struct __packed (like struct alt_instr) and get rid
of all the .align directives? Am I missing something?