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 11AB2CEE33B for ; Tue, 18 Nov 2025 17:09:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Cc:Content-ID:Content-Description:Resent-Date:Resent-From :Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=xA75Nc+EsSknPn3jEM8iZ2cQyKWxLBBNMrMgRm9WUfQ=; b=nEcOJxQXnYryoH24a6aOf/VuDz iT3FEe7UP6zpUkKhZPqqBSgczIWxOii0Q4y9abG/dR7DNOZgtbgLcu+qAdMfX1mG0xVAb56WNRVad cwh5p2v4B3igBiVC/g+MrSE3txeV1fwyAyLjzlYi2uA0fXjjKZRNGl7FfFhm/JX5n2x37jzKOrVBh CudsKo4vvgYxb3PBZvxug05Q2g5rIClQvoJVEinj2NR7kzj8gLIWAlLGYa1BZvxKsaWVTz3kzi+Uh QEoVv6y7Pnw7WhOwWzURgB8DKrsMoQMKumj0FeBRH/Mx7K9UVRS7BODELYBXfeatm721SrQ2IQZpJ tdcDfkGQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vLPD1-00000000osu-2eqD; Tue, 18 Nov 2025 17:09:39 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vLPCz-00000000os1-0I34 for linux-arm-kernel@lists.infradead.org; Tue, 18 Nov 2025 17:09:38 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E205A497; Tue, 18 Nov 2025 09:09:26 -0800 (PST) Received: from [10.57.39.196] (unknown [10.57.39.196]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A87D83F66E; Tue, 18 Nov 2025 09:09:29 -0800 (PST) Message-ID: <970d9689-4188-4c40-92e6-bdf1e589e8a2@arm.com> Date: Tue, 18 Nov 2025 18:09:26 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v7 01/11] arm64/ptrace: Split report_syscall() To: Jinjie Ruan , catalin.marinas@arm.com, will@kernel.org, oleg@redhat.com, tglx@linutronix.de, peterz@infradead.org, luto@kernel.org, shuah@kernel.org, kees@kernel.org, wad@chromium.org, akpm@linux-foundation.org, ldv@strace.io, macro@orcam.me.uk, deller@gmx.de, mark.rutland@arm.com, song@kernel.org, mbenes@suse.cz, ryan.roberts@arm.com, ada.coupriediaz@arm.com, anshuman.khandual@arm.com, broonie@kernel.org, pengcan@kylinos.cn, dvyukov@google.com, kmal@cock.li, lihongbo22@huawei.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org References: <20251117133048.53182-1-ruanjinjie@huawei.com> <20251117133048.53182-2-ruanjinjie@huawei.com> From: Kevin Brodsky Content-Language: en-GB In-Reply-To: <20251117133048.53182-2-ruanjinjie@huawei.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251118_090937_231673_B529D145 X-CRM114-Status: GOOD ( 20.99 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 17/11/2025 14:30, Jinjie Ruan wrote: > The generic syscall entry code has the form: > > | syscall_trace_enter() > | { > | ptrace_report_syscall_entry() > | } > | > | syscall_exit_work() > | { > | ptrace_report_syscall_exit() > | } > > In preparation for moving arm64 over to the generic entry code, split > report_syscall() to two separate enter and exit functions to align > the structure of the arm64 code with syscall_trace_enter() and > syscall_exit_work() from the generic entry code. > > No functional changes. > > Suggested-by: Mark Rutland > Signed-off-by: Jinjie Ruan > --- > arch/arm64/kernel/ptrace.c | 29 ++++++++++++++++++++--------- > 1 file changed, 20 insertions(+), 9 deletions(-) > > diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c > index 4b001121c72d..5534c175ceb7 100644 > --- a/arch/arm64/kernel/ptrace.c > +++ b/arch/arm64/kernel/ptrace.c > @@ -2317,7 +2317,7 @@ enum ptrace_syscall_dir { > PTRACE_SYSCALL_EXIT, > }; This is now unused so it should be removed. > > -static void report_syscall(struct pt_regs *regs, enum ptrace_syscall_dir dir) > +static void report_syscall_enter(struct pt_regs *regs) Nit: better to call it "report_syscall_entry" to match its final name. > { > int regno; > unsigned long saved_reg; > @@ -2340,13 +2340,24 @@ static void report_syscall(struct pt_regs *regs, enum ptrace_syscall_dir dir) > */ > regno = (is_compat_task() ? 12 : 7); > saved_reg = regs->regs[regno]; > - regs->regs[regno] = dir; > + regs->regs[regno] = PTRACE_SYSCALL_ENTER; > > - if (dir == PTRACE_SYSCALL_ENTER) { > - if (ptrace_report_syscall_entry(regs)) > - forget_syscall(regs); > - regs->regs[regno] = saved_reg; > - } else if (!test_thread_flag(TIF_SINGLESTEP)) { > + if (ptrace_report_syscall_entry(regs)) > + forget_syscall(regs); > + regs->regs[regno] = saved_reg; > +} > + > +static void report_syscall_exit(struct pt_regs *regs) > +{ > + int regno; > + unsigned long saved_reg; > + > + /* See comment for report_syscall_enter() above */ > + regno = (is_compat_task() ? 12 : 7); Probably best not to duplicate such magic numbers, moving this line to a helper would be good. - Kevin > + saved_reg = regs->regs[regno]; > + regs->regs[regno] = PTRACE_SYSCALL_EXIT; > + > + if (!test_thread_flag(TIF_SINGLESTEP)) { > ptrace_report_syscall_exit(regs, 0); > regs->regs[regno] = saved_reg; > } else { > @@ -2366,7 +2377,7 @@ int syscall_trace_enter(struct pt_regs *regs) > unsigned long flags = read_thread_flags(); > > if (flags & (_TIF_SYSCALL_EMU | _TIF_SYSCALL_TRACE)) { > - report_syscall(regs, PTRACE_SYSCALL_ENTER); > + report_syscall_enter(regs); > if (flags & _TIF_SYSCALL_EMU) > return NO_SYSCALL; > } > @@ -2394,7 +2405,7 @@ void syscall_trace_exit(struct pt_regs *regs) > trace_sys_exit(regs, syscall_get_return_value(current, regs)); > > if (flags & (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP)) > - report_syscall(regs, PTRACE_SYSCALL_EXIT); > + report_syscall_exit(regs); > > rseq_syscall(regs); > }