From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A981BC636CD for ; Wed, 1 Feb 2023 13:30:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:References :In-Reply-To:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=NPCvPO8EMBr12OTZXiCjMQeYfHJ0gAnYEb8nIZ5VFho=; b=UX7K7Y9Xhh1fKg 7SWNshqcCykrHD5HpBIG7iJ2xC7ZYXryE5KlS+YdKmpCe6mcSegPsiRVPBfrgQSIVz3tbrV0+XUFr m7iF81Ldgj5I5idKSBN3Yi4RL2d1TTFeoKgKR2dJgOPLZHbKCLUKdBc4xNJj9w6XsCoSVOwyt/82U 9A+ixNbSoCYU0BPu7TK1Wri7cgsGdA8EYxh2NhT97eI8cNSbdjmmIlFQYcNyXZ2LPPJ2yYptlBjmJ BlPrFJvycRShpe5O47IhOyNSIqLrmqaL68s9wim0F5TnL7JHnrr6ldmbzTTebC8hPdhEJXWNjZt2I eas/DgzVqJTdVx90j75w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pNDBh-00C4EY-H6; Wed, 01 Feb 2023 13:30:09 +0000 Received: from ams.source.kernel.org ([2604:1380:4601:e00::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pNDBf-00C4CL-7T for linux-riscv@lists.infradead.org; Wed, 01 Feb 2023 13:30:08 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id D0BB1B82188; Wed, 1 Feb 2023 13:30:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2EB4AC433D2; Wed, 1 Feb 2023 13:30:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675258204; bh=PDRhcGJ17Tvv0fPAUYuSJW7rVUzUKearobtYgs9at/A=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=pAatRhSGMokeGNVuQJGZ/boTlD0T2LGuzdJOv8rZSmG4QFGAETe9dW4CL/5uqX1tf hiRntJ9OyEP63OdrKLI6KDbSVtG92Raz+N9mboJgHl8s2TExUOpVQSrqFYIUbCS4kD kl0NChOBUxSId6xbchT7g5mhstI1LuaRZ1wRDBKmefzp/JQkkofF4vioCEVDmN8uis ApkXnWjUJYiRRzCiaY/KSNcrxTFC1BC7Tf7IiirCK0B3ShUTDYOFwpA87MYn0ANbEQ E5Ceioh9LdJgQKlgQcv45liEpDv2xEfVOrTZ4rrUPaRa9bL6C5rfZJ92oeE0Hece1M WsO8Zd8qtAI0Q== From: =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= To: Chen Guokai , paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, rostedt@goodmis.org, mingo@redhat.com, sfr@canb.auug.org.au Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, liaochang1@huawei.com, Chen Guokai Subject: Re: [PATCH v6 06/13] riscv/kprobe: Add code to check if kprobe can be optimized In-Reply-To: <20230127130541.1250865-7-chenguokai17@mails.ucas.ac.cn> References: <20230127130541.1250865-1-chenguokai17@mails.ucas.ac.cn> <20230127130541.1250865-7-chenguokai17@mails.ucas.ac.cn> Date: Wed, 01 Feb 2023 14:30:01 +0100 Message-ID: <87wn51tsx2.fsf@all.your.base.are.belong.to.us> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230201_053007_442047_E94AF66C X-CRM114-Status: UNSURE ( 9.06 ) X-CRM114-Notice: Please train this message. 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d=kernel.org; s=k20201202; t=1675258204; bh=PDRhcGJ17Tvv0fPAUYuSJW7rVUzUKearobtYgs9at/A=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=pAatRhSGMokeGNVuQJGZ/boTlD0T2LGuzdJOv8rZSmG4QFGAETe9dW4CL/5uqX1tf hiRntJ9OyEP63OdrKLI6KDbSVtG92Raz+N9mboJgHl8s2TExUOpVQSrqFYIUbCS4kD kl0NChOBUxSId6xbchT7g5mhstI1LuaRZ1wRDBKmefzp/JQkkofF4vioCEVDmN8uis ApkXnWjUJYiRRzCiaY/KSNcrxTFC1BC7Tf7IiirCK0B3ShUTDYOFwpA87MYn0ANbEQ E5Ceioh9LdJgQKlgQcv45liEpDv2xEfVOrTZ4rrUPaRa9bL6C5rfZJ92oeE0Hece1M WsO8Zd8qtAI0Q== From: =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= To: Chen Guokai , paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, rostedt@goodmis.org, mingo@redhat.com, sfr@canb.auug.org.au Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, liaochang1@huawei.com, Chen Guokai Subject: Re: [PATCH v6 06/13] riscv/kprobe: Add code to check if kprobe can be optimized In-Reply-To: <20230127130541.1250865-7-chenguokai17@mails.ucas.ac.cn> References: <20230127130541.1250865-1-chenguokai17@mails.ucas.ac.cn> <20230127130541.1250865-7-chenguokai17@mails.ucas.ac.cn> Date: Wed, 01 Feb 2023 14:30:01 +0100 Message-ID: <87wn51tsx2.fsf@all.your.base.are.belong.to.us> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Chen Guokai writes: > From: Liao Chang > > For the RVI and RVC hybrid encoding kernel, although AUIPC/JALR just > occupy 8 bytes space, the patched code is 10 bytes at the worst case > to ensure no RVI is truncated, so to check if kprobe satisfies the > requirement of jump optimization, it has to find out an instruction > window large enough to patch AUIPC/JALR(and padding C.NOP), and ensure > no instruction nearby jumps into the patching window. > > Besides that, this series does not support the simulation of pc-relative > instruction in optprobe handler yet, so the patching window should not > includes pc-relative instruction. > > Signed-off-by: Liao Chang > Co-developed-by: Chen Guokai > Signed-off-by: Chen Guokai Reviewed-by: Bj=C3=B6rn T=C3=B6pel