From: "H. Peter Anvin" <hpa@zytor.com>
To: Luca Barbieri <luca@luca-barbieri.com>
Cc: mingo@elte.hu, a.p.zijlstra@chello.nl, akpm@linux-foundation.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH 02/10] x86: add support for relative CALL and JMP in alternatives
Date: Thu, 18 Feb 2010 11:40:22 -0800 [thread overview]
Message-ID: <4B7D97A6.4060900@zytor.com> (raw)
In-Reply-To: <1266406962-17463-3-git-send-email-luca@luca-barbieri.com>
On 02/17/2010 03:42 AM, Luca Barbieri wrote:
> Currently CALL and JMP cannot be used in alternatives because the
> relative offset would be wrong.
>
> This patch uses the existing x86 instruction parser to parse the
> alternative sequence and fix up the displacements.
>
> This allows to implement this feature with minimal code.
>
The existing instruction parser is only present if KPROBES is configured
in... this patch would make it obligatory. Your patch doesn't reflect
that. Furthermore, it is ~16K of code and data which probably will make
embedded people unhappy... although perhaps isn't out of line.
A good question, though, is if we actually need support for JMP or CALL
as anything but the first instruction (usually the *only* instruction),
which would make it a lot easier...
-hpa
next prev parent reply other threads:[~2010-02-18 19:41 UTC|newest]
Thread overview: 54+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-02-17 11:42 [PATCH 0/10] x86-32: improve atomic64_t functions Luca Barbieri
2010-02-17 11:42 ` [PATCH 01/10] x86: add support for multiple choice alternatives Luca Barbieri
2010-02-17 12:47 ` Avi Kivity
2010-02-18 19:46 ` H. Peter Anvin
2010-02-17 11:42 ` [PATCH 02/10] x86: add support for relative CALL and JMP in alternatives Luca Barbieri
2010-02-18 19:40 ` H. Peter Anvin [this message]
2010-02-18 23:38 ` Luca Barbieri
2010-02-18 23:54 ` H. Peter Anvin
2010-02-19 14:27 ` Masami Hiramatsu
2010-02-17 11:42 ` [PATCH 03/10] x86: add support for lock prefix " Luca Barbieri
2010-02-17 11:42 ` [PATCH 04/10] x86-32: allow UP/SMP lock replacement in cmpxchg64 Luca Barbieri
2010-02-17 11:42 ` [PATCH 05/10] lib: add self-test for atomic64_t Luca Barbieri
2010-02-17 11:42 ` [PATCH 06/10] x86-32: rewrite 32-bit atomic64 functions in assembly Luca Barbieri
2010-02-17 11:42 ` [PATCH 07/10] lib: move generic atomic64 to atomic64-impl.h Luca Barbieri
2010-02-17 11:42 ` [PATCH 08/10] x86-32: support atomic64_t on 386/486 UP/SMP Luca Barbieri
2010-02-18 10:25 ` Peter Zijlstra
2010-02-18 10:58 ` Luca Barbieri
2010-02-18 15:20 ` H. Peter Anvin
2010-02-17 11:42 ` [PATCH 09/10] x86-32: use SSE for atomic64_read/set if available Luca Barbieri
2010-02-17 22:39 ` H. Peter Anvin
2010-02-18 0:41 ` Luca Barbieri
2010-02-18 0:47 ` H. Peter Anvin
2010-02-18 9:56 ` Avi Kivity
2010-02-18 10:07 ` Luca Barbieri
2010-02-18 8:23 ` Andi Kleen
2010-02-18 9:53 ` Luca Barbieri
2010-02-18 9:56 ` Luca Barbieri
2010-02-18 10:11 ` Andi Kleen
2010-02-18 10:27 ` Luca Barbieri
2010-02-18 15:24 ` H. Peter Anvin
2010-02-18 18:14 ` Luca Barbieri
2010-02-18 18:28 ` H. Peter Anvin
2010-02-18 18:42 ` Luca Barbieri
2010-02-18 19:07 ` H. Peter Anvin
2010-02-18 20:26 ` Andi Kleen
2010-02-18 16:52 ` H. Peter Anvin
2010-02-18 18:49 ` Luca Barbieri
2010-02-18 19:06 ` H. Peter Anvin
2010-02-18 19:43 ` Luca Barbieri
2010-02-18 19:45 ` Yuhong Bao
2010-02-18 10:24 ` Peter Zijlstra
2010-02-18 10:25 ` Peter Zijlstra
2010-02-18 10:50 ` Luca Barbieri
2010-02-18 11:00 ` Peter Zijlstra
2010-02-18 12:29 ` Luca Barbieri
2010-02-18 12:32 ` Peter Zijlstra
2010-02-18 13:45 ` Luca Barbieri
2010-02-17 11:42 ` [PATCH 10/10] x86-32: panic on !CX8 && XMM Luca Barbieri
2010-02-17 22:38 ` H. Peter Anvin
2010-02-17 23:00 ` Yuhong Bao
2010-02-17 23:41 ` H. Peter Anvin
2010-02-18 1:13 ` Yuhong Bao
2010-02-25 20:24 ` Yuhong Bao
2010-02-18 0:46 ` Luca Barbieri
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