From nobody Fri Dec 27 22:29:56 2024 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D5A92211702 for ; Fri, 6 Dec 2024 10:18:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.188 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733480310; cv=none; b=MIKfsZ28spwqOj8uyTI+easgSDj8dSSIwnZenpSEADYg6NzVxWMN885iZUgV3boAPufVJ9yH/gryfMAaVuxUcpGv6sX2d5KIASxNXZA/8neaoJkFHM8fIZ+jk0rMjWOreYXOA03ak0vUAR7w9f5OUViX+fI0n8SPk1fEgmRuATw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733480310; c=relaxed/simple; bh=5EzbUZRisG9ikZ8+iJRdob7XU5ICnl/53pdRmOi4nkk=; h=From:To:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=se6bCW3Q4ml01C4UexCfrJkCqoBLfvBRohTNRI45T6Im67dNTdNDBQ9I03mPv+LNhoNVpEbDlX8Pud9AUQRyxgP8YJUSKsUDQnsCleFhNn2JdjtpDCEvH4daHrMaBktEQnDABwIww4JDRgfTb41/Y/CKhM4gP8TYkle9Mr0Hu6A= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.188 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.163.48]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4Y4RwQ3XBKzgZ8D; Fri, 6 Dec 2024 18:15:34 +0800 (CST) Received: from kwepemg200008.china.huawei.com (unknown [7.202.181.35]) by mail.maildlp.com (Postfix) with ESMTPS id 41FA418009B; Fri, 6 Dec 2024 18:18:25 +0800 (CST) Received: from huawei.com (10.90.53.73) by kwepemg200008.china.huawei.com (7.202.181.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Fri, 6 Dec 2024 18:18:23 +0800 From: Jinjie Ruan To: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , Subject: [PATCH -next v5 15/22] arm64/ptrace: Refator el0_svc_common() Date: Fri, 6 Dec 2024 18:17:37 +0800 Message-ID: <20241206101744.4161990-16-ruanjinjie@huawei.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20241206101744.4161990-1-ruanjinjie@huawei.com> References: <20241206101744.4161990-1-ruanjinjie@huawei.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemg200008.china.huawei.com (7.202.181.35) Content-Type: text/plain; charset="utf-8" As the generic entry, before report_syscall_exit(), it terminate the process if the syscall is issued within a restartable sequence. In preparation for moving arm64 over to the generic entry code, refator el0_svc_common() as below: - Extract syscall_exit_to_user_mode_prepare() helper to replace the the combination of read_thread_flags() and syscall_trace_exit(), also move the syscall exit check logic into it. - Move rseq_syscall() ahead, so the CONFIG_DEBUG_RSEQ check is not needed. - Move has_syscall_work() helper into asm/syscall.h to be reused for ptrace.c. Signed-off-by: Jinjie Ruan --- arch/arm64/include/asm/syscall.h | 7 ++++++- arch/arm64/kernel/ptrace.c | 10 +++++++++- arch/arm64/kernel/syscall.c | 26 +++++--------------------- 3 files changed, 20 insertions(+), 23 deletions(-) diff --git a/arch/arm64/include/asm/syscall.h b/arch/arm64/include/asm/sysc= all.h index 925a257145f9..6eeb1e7b033f 100644 --- a/arch/arm64/include/asm/syscall.h +++ b/arch/arm64/include/asm/syscall.h @@ -85,7 +85,12 @@ static inline int syscall_get_arch(struct task_struct *t= ask) return AUDIT_ARCH_AARCH64; } =20 +static inline bool has_syscall_work(unsigned long flags) +{ + return unlikely(flags & _TIF_SYSCALL_WORK); +} + int syscall_trace_enter(struct pt_regs *regs, long syscall, unsigned long = flags); -void syscall_trace_exit(struct pt_regs *regs, unsigned long flags); +void syscall_exit_to_user_mode_prepare(struct pt_regs *regs); =20 #endif /* __ASM_SYSCALL_H */ diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index bb994d668d74..23df2e558fe9 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -2384,7 +2384,7 @@ int syscall_trace_enter(struct pt_regs *regs, long sy= scall, unsigned long flags) return regs->syscallno; } =20 -void syscall_trace_exit(struct pt_regs *regs, unsigned long flags) +static void syscall_trace_exit(struct pt_regs *regs, unsigned long flags) { audit_syscall_exit(regs); =20 @@ -2393,8 +2393,16 @@ void syscall_trace_exit(struct pt_regs *regs, unsign= ed long flags) =20 if (flags & (_TIF_SYSCALL_TRACE | _TIF_SINGLESTEP)) report_syscall_exit(regs); +} + +void syscall_exit_to_user_mode_prepare(struct pt_regs *regs) +{ + unsigned long flags =3D read_thread_flags(); =20 rseq_syscall(regs); + + if (has_syscall_work(flags) || flags & _TIF_SINGLESTEP) + syscall_trace_exit(regs, flags); } =20 /* diff --git a/arch/arm64/kernel/syscall.c b/arch/arm64/kernel/syscall.c index 064dc114fb9b..a50db885fc34 100644 --- a/arch/arm64/kernel/syscall.c +++ b/arch/arm64/kernel/syscall.c @@ -65,11 +65,6 @@ static void invoke_syscall(struct pt_regs *regs, unsigne= d int scno, choose_random_kstack_offset(get_random_u16()); } =20 -static inline bool has_syscall_work(unsigned long flags) -{ - return unlikely(flags & _TIF_SYSCALL_WORK); -} - static void el0_svc_common(struct pt_regs *regs, int scno, int sc_nr, const syscall_fn_t syscall_table[]) { @@ -125,26 +120,15 @@ static void el0_svc_common(struct pt_regs *regs, int = scno, int sc_nr, if (scno =3D=3D NO_SYSCALL) syscall_set_return_value(current, regs, -ENOSYS, 0); scno =3D syscall_trace_enter(regs, regs->syscallno, flags); - if (scno =3D=3D NO_SYSCALL) - goto trace_exit; + if (scno =3D=3D NO_SYSCALL) { + syscall_exit_to_user_mode_prepare(regs); + return; + } } =20 invoke_syscall(regs, scno, sc_nr, syscall_table); =20 - /* - * The tracing status may have changed under our feet, so we have to - * check again. However, if we were tracing entry, then we always trace - * exit regardless, as the old entry assembly did. - */ - if (!has_syscall_work(flags) && !IS_ENABLED(CONFIG_DEBUG_RSEQ)) { - flags =3D read_thread_flags(); - if (!has_syscall_work(flags) && !(flags & _TIF_SINGLESTEP)) - return; - } - -trace_exit: - flags =3D read_thread_flags(); - syscall_trace_exit(regs, flags); + syscall_exit_to_user_mode_prepare(regs); } =20 void do_el0_svc(struct pt_regs *regs) --=20 2.34.1