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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B549DC43334 for ; Fri, 1 Jul 2022 19:53:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231684AbiGATxg (ORCPT ); Fri, 1 Jul 2022 15:53:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32908 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231557AbiGATxe (ORCPT ); Fri, 1 Jul 2022 15:53:34 -0400 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id B69C82DD5F; Fri, 1 Jul 2022 12:53:32 -0700 (PDT) Received: from [192.168.254.32] (unknown [47.189.24.195]) by linux.microsoft.com (Postfix) with ESMTPSA id 73BBB20D4D81; Fri, 1 Jul 2022 12:53:31 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 73BBB20D4D81 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1656705212; bh=GWy2YeVuMJUaFDcJYtow9oLioamoe+ff03AojkonNx8=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=IKZGO7wjlIW630K+t+j77XST3E9Bvb+6B5S+KUKfFB8d4OBOdz8JtCIfBXKI3Q2U1 CrMDyTtTsLep67lNEdOu+XPJCQ49o01fWw0ItUQgFj1UkIT9iaDiYQV06pTCJ5Pg4A uC5xI0yQRw1fodp3owj/PRkB8XjaLs0gDshSkivI= Message-ID: <884d1d23-84ee-38ad-2bff-40b2d046fbf2@linux.microsoft.com> Date: Fri, 1 Jul 2022 14:53:30 -0500 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [RFC PATCH v2 19/20] arm64: Miscellaneous changes required for enabling livepatch Content-Language: en-US To: Miroslav Benes Cc: jpoimboe@redhat.com, peterz@infradead.org, chenzhongjin@huawei.com, mark.rutland@arm.com, broonie@kernel.org, nobuta.keiya@fujitsu.com, sjitindarsingh@gmail.com, catalin.marinas@arm.com, will@kernel.org, jamorris@linux.microsoft.com, linux-arm-kernel@lists.infradead.org, live-patching@vger.kernel.org, linux-kernel@vger.kernel.org References: <20220524001637.1707472-1-madvenka@linux.microsoft.com> <20220524001637.1707472-20-madvenka@linux.microsoft.com> From: "Madhavan T. Venkataraman" In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thanks for the review. On 7/1/22 09:16, Miroslav Benes wrote: > Hi, > > sorry for the late reply... > > On Mon, 23 May 2022, madvenka@linux.microsoft.com wrote: > >> From: "Madhavan T. Venkataraman" >> >> - Create arch/arm64/include/asm/livepatch.h and define >> klp_arch_set_pc() and klp_get_ftrace_location() which >> are required for livepatch. >> >> - Define TIF_PATCH_PENDING in arch/arm64/include/asm/thread_info.h >> for livepatch. >> >> - Check TIF_PATCH_PENDING in do_notify_resume() to patch the >> current task for livepatch. >> >> Signed-off-by: Suraj Jitindar Singh >> Signed-off-by: Madhavan T. Venkataraman >> --- >> arch/arm64/include/asm/livepatch.h | 42 ++++++++++++++++++++++++++++ >> arch/arm64/include/asm/thread_info.h | 4 ++- >> arch/arm64/kernel/signal.c | 4 +++ >> 3 files changed, 49 insertions(+), 1 deletion(-) >> create mode 100644 arch/arm64/include/asm/livepatch.h >> >> diff --git a/arch/arm64/include/asm/livepatch.h b/arch/arm64/include/asm/livepatch.h >> new file mode 100644 >> index 000000000000..72d7cd86f158 >> --- /dev/null >> +++ b/arch/arm64/include/asm/livepatch.h >> @@ -0,0 +1,42 @@ >> +/* SPDX-License-Identifier: GPL-2.0 >> + * >> + * livepatch.h - arm64-specific Kernel Live Patching Core >> + */ >> +#ifndef _ASM_ARM64_LIVEPATCH_H >> +#define _ASM_ARM64_LIVEPATCH_H >> + >> +#include >> + >> +static inline void klp_arch_set_pc(struct ftrace_regs *fregs, unsigned long ip) >> +{ >> + struct pt_regs *regs = ftrace_get_regs(fregs); >> + >> + regs->pc = ip; >> +} > > kernel/livepatch/ does not use klp_arch_set_pc() anymore. It was replaced > by ftrace_instruction_pointer_set() and > CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS. > OK. I will address this in the next version. Thanks for pointing it out. >> +/* >> + * klp_get_ftrace_location is expected to return the address of the BL to the >> + * relevant ftrace handler in the callsite. The location of this can vary based >> + * on several compilation options. >> + * CONFIG_DYNAMIC_FTRACE_WITH_REGS >> + * - Inserts 2 nops on function entry the second of which is the BL >> + * referenced above. (See ftrace_init_nop() for the callsite sequence) >> + * (this is required by livepatch and must be selected) >> + * CONFIG_ARM64_BTI_KERNEL: >> + * - Inserts a hint #0x22 on function entry if the function is called >> + * indirectly (to satisfy BTI requirements), which is inserted before >> + * the two nops from above. >> + */ >> +#define klp_get_ftrace_location klp_get_ftrace_location >> +static inline unsigned long klp_get_ftrace_location(unsigned long faddr) >> +{ >> + unsigned long addr = faddr + AARCH64_INSN_SIZE; >> + >> +#if IS_ENABLED(CONFIG_ARM64_BTI_KERNEL) >> + addr = ftrace_location_range(addr, addr + AARCH64_INSN_SIZE); >> +#endif >> + >> + return addr; >> +} > > This is not needed either. peterz improved the ftrace code and livepatch > now uses ftrace_location() which gives the proper location directly. > OK. I will remove this in the next version. >> diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h >> index e1317b7c4525..a1d8999dbdcc 100644 >> --- a/arch/arm64/include/asm/thread_info.h >> +++ b/arch/arm64/include/asm/thread_info.h >> @@ -68,6 +68,7 @@ int arch_dup_task_struct(struct task_struct *dst, >> #define TIF_UPROBE 4 /* uprobe breakpoint or singlestep */ >> #define TIF_MTE_ASYNC_FAULT 5 /* MTE Asynchronous Tag Check Fault */ >> #define TIF_NOTIFY_SIGNAL 6 /* signal notifications exist */ >> +#define TIF_PATCH_PENDING 7 /* pending live patching update */ >> #define TIF_SYSCALL_TRACE 8 /* syscall trace active */ >> #define TIF_SYSCALL_AUDIT 9 /* syscall auditing */ >> #define TIF_SYSCALL_TRACEPOINT 10 /* syscall tracepoint for ftrace */ >> @@ -98,11 +99,12 @@ int arch_dup_task_struct(struct task_struct *dst, >> #define _TIF_SVE (1 << TIF_SVE) >> #define _TIF_MTE_ASYNC_FAULT (1 << TIF_MTE_ASYNC_FAULT) >> #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL) >> +#define _TIF_PATCH_PENDING (1 << TIF_PATCH_PENDING) >> >> #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ >> _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ >> _TIF_UPROBE | _TIF_MTE_ASYNC_FAULT | \ >> - _TIF_NOTIFY_SIGNAL) >> + _TIF_NOTIFY_SIGNAL | _TIF_PATCH_PENDING) >> >> #define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ >> _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \ >> diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c >> index 4a4122ef6f39..cbec9597349f 100644 >> --- a/arch/arm64/kernel/signal.c >> +++ b/arch/arm64/kernel/signal.c >> @@ -17,6 +17,7 @@ >> #include >> #include >> #include >> +#include >> #include >> #include >> >> @@ -938,6 +939,9 @@ void do_notify_resume(struct pt_regs *regs, unsigned long thread_flags) >> (void __user *)NULL, current); >> } >> >> + if (thread_flags & _TIF_PATCH_PENDING) >> + klp_update_patch_state(current); >> + >> if (thread_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) >> do_signal(regs); > > The rest should be fine. > Thanks! Madhavan 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 002C1C43334 for ; Fri, 1 Jul 2022 19:54:45 +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:In-Reply-To:From:References:Cc:To: Subject:MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=FWriyYqaFNOyrvslgsRdy+GtL0LNQKQWkmVyVsdmAdg=; b=xt95bRvGB7Xjmm 6kJ3h3D7NM43La3wPJ9u1btKYeQoocltYNGisna7TE8Rd6nzNU545PdERqaXvZGk+RnEYjtq+aWMz M20yqUd+Fb2eqM4JQEC1ehe+Z8KyuG8Rwz6SneIyhw0vv6m2MYvxLliz2bPK+nLLfGAXD/CTWB9x+ BmhptALclJ8hcpq7btprnGU5fDidSfJbs9Czg7Cd+gnn3JonB0HSqm+bKh5JfhdYLP9bQBeeB9kvn Iyx1HjcC7iDG8lasknFL1Lx6skkSvEezzCecEudHI/DjIWKS8Sv4j7wMZ26odkl/llkuZYwVErFmr fhWsbyLLi0ehUMbjzSoQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1o7Mhy-006hmn-Dp; Fri, 01 Jul 2022 19:53:42 +0000 Received: from linux.microsoft.com ([13.77.154.182]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1o7Mhv-006hke-32 for linux-arm-kernel@lists.infradead.org; Fri, 01 Jul 2022 19:53:40 +0000 Received: from [192.168.254.32] (unknown [47.189.24.195]) by linux.microsoft.com (Postfix) with ESMTPSA id 73BBB20D4D81; Fri, 1 Jul 2022 12:53:31 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 73BBB20D4D81 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1656705212; bh=GWy2YeVuMJUaFDcJYtow9oLioamoe+ff03AojkonNx8=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=IKZGO7wjlIW630K+t+j77XST3E9Bvb+6B5S+KUKfFB8d4OBOdz8JtCIfBXKI3Q2U1 CrMDyTtTsLep67lNEdOu+XPJCQ49o01fWw0ItUQgFj1UkIT9iaDiYQV06pTCJ5Pg4A uC5xI0yQRw1fodp3owj/PRkB8XjaLs0gDshSkivI= Message-ID: <884d1d23-84ee-38ad-2bff-40b2d046fbf2@linux.microsoft.com> Date: Fri, 1 Jul 2022 14:53:30 -0500 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [RFC PATCH v2 19/20] arm64: Miscellaneous changes required for enabling livepatch Content-Language: en-US To: Miroslav Benes Cc: jpoimboe@redhat.com, peterz@infradead.org, chenzhongjin@huawei.com, mark.rutland@arm.com, broonie@kernel.org, nobuta.keiya@fujitsu.com, sjitindarsingh@gmail.com, catalin.marinas@arm.com, will@kernel.org, jamorris@linux.microsoft.com, linux-arm-kernel@lists.infradead.org, live-patching@vger.kernel.org, linux-kernel@vger.kernel.org References: <20220524001637.1707472-1-madvenka@linux.microsoft.com> <20220524001637.1707472-20-madvenka@linux.microsoft.com> From: "Madhavan T. Venkataraman" In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220701_125339_227277_DE5635E5 X-CRM114-Status: GOOD ( 25.98 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Thanks for the review. On 7/1/22 09:16, Miroslav Benes wrote: > Hi, > > sorry for the late reply... > > On Mon, 23 May 2022, madvenka@linux.microsoft.com wrote: > >> From: "Madhavan T. Venkataraman" >> >> - Create arch/arm64/include/asm/livepatch.h and define >> klp_arch_set_pc() and klp_get_ftrace_location() which >> are required for livepatch. >> >> - Define TIF_PATCH_PENDING in arch/arm64/include/asm/thread_info.h >> for livepatch. >> >> - Check TIF_PATCH_PENDING in do_notify_resume() to patch the >> current task for livepatch. >> >> Signed-off-by: Suraj Jitindar Singh >> Signed-off-by: Madhavan T. Venkataraman >> --- >> arch/arm64/include/asm/livepatch.h | 42 ++++++++++++++++++++++++++++ >> arch/arm64/include/asm/thread_info.h | 4 ++- >> arch/arm64/kernel/signal.c | 4 +++ >> 3 files changed, 49 insertions(+), 1 deletion(-) >> create mode 100644 arch/arm64/include/asm/livepatch.h >> >> diff --git a/arch/arm64/include/asm/livepatch.h b/arch/arm64/include/asm/livepatch.h >> new file mode 100644 >> index 000000000000..72d7cd86f158 >> --- /dev/null >> +++ b/arch/arm64/include/asm/livepatch.h >> @@ -0,0 +1,42 @@ >> +/* SPDX-License-Identifier: GPL-2.0 >> + * >> + * livepatch.h - arm64-specific Kernel Live Patching Core >> + */ >> +#ifndef _ASM_ARM64_LIVEPATCH_H >> +#define _ASM_ARM64_LIVEPATCH_H >> + >> +#include >> + >> +static inline void klp_arch_set_pc(struct ftrace_regs *fregs, unsigned long ip) >> +{ >> + struct pt_regs *regs = ftrace_get_regs(fregs); >> + >> + regs->pc = ip; >> +} > > kernel/livepatch/ does not use klp_arch_set_pc() anymore. It was replaced > by ftrace_instruction_pointer_set() and > CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS. > OK. I will address this in the next version. Thanks for pointing it out. >> +/* >> + * klp_get_ftrace_location is expected to return the address of the BL to the >> + * relevant ftrace handler in the callsite. The location of this can vary based >> + * on several compilation options. >> + * CONFIG_DYNAMIC_FTRACE_WITH_REGS >> + * - Inserts 2 nops on function entry the second of which is the BL >> + * referenced above. (See ftrace_init_nop() for the callsite sequence) >> + * (this is required by livepatch and must be selected) >> + * CONFIG_ARM64_BTI_KERNEL: >> + * - Inserts a hint #0x22 on function entry if the function is called >> + * indirectly (to satisfy BTI requirements), which is inserted before >> + * the two nops from above. >> + */ >> +#define klp_get_ftrace_location klp_get_ftrace_location >> +static inline unsigned long klp_get_ftrace_location(unsigned long faddr) >> +{ >> + unsigned long addr = faddr + AARCH64_INSN_SIZE; >> + >> +#if IS_ENABLED(CONFIG_ARM64_BTI_KERNEL) >> + addr = ftrace_location_range(addr, addr + AARCH64_INSN_SIZE); >> +#endif >> + >> + return addr; >> +} > > This is not needed either. peterz improved the ftrace code and livepatch > now uses ftrace_location() which gives the proper location directly. > OK. I will remove this in the next version. >> diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h >> index e1317b7c4525..a1d8999dbdcc 100644 >> --- a/arch/arm64/include/asm/thread_info.h >> +++ b/arch/arm64/include/asm/thread_info.h >> @@ -68,6 +68,7 @@ int arch_dup_task_struct(struct task_struct *dst, >> #define TIF_UPROBE 4 /* uprobe breakpoint or singlestep */ >> #define TIF_MTE_ASYNC_FAULT 5 /* MTE Asynchronous Tag Check Fault */ >> #define TIF_NOTIFY_SIGNAL 6 /* signal notifications exist */ >> +#define TIF_PATCH_PENDING 7 /* pending live patching update */ >> #define TIF_SYSCALL_TRACE 8 /* syscall trace active */ >> #define TIF_SYSCALL_AUDIT 9 /* syscall auditing */ >> #define TIF_SYSCALL_TRACEPOINT 10 /* syscall tracepoint for ftrace */ >> @@ -98,11 +99,12 @@ int arch_dup_task_struct(struct task_struct *dst, >> #define _TIF_SVE (1 << TIF_SVE) >> #define _TIF_MTE_ASYNC_FAULT (1 << TIF_MTE_ASYNC_FAULT) >> #define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL) >> +#define _TIF_PATCH_PENDING (1 << TIF_PATCH_PENDING) >> >> #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ >> _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ >> _TIF_UPROBE | _TIF_MTE_ASYNC_FAULT | \ >> - _TIF_NOTIFY_SIGNAL) >> + _TIF_NOTIFY_SIGNAL | _TIF_PATCH_PENDING) >> >> #define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ >> _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \ >> diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c >> index 4a4122ef6f39..cbec9597349f 100644 >> --- a/arch/arm64/kernel/signal.c >> +++ b/arch/arm64/kernel/signal.c >> @@ -17,6 +17,7 @@ >> #include >> #include >> #include >> +#include >> #include >> #include >> >> @@ -938,6 +939,9 @@ void do_notify_resume(struct pt_regs *regs, unsigned long thread_flags) >> (void __user *)NULL, current); >> } >> >> + if (thread_flags & _TIF_PATCH_PENDING) >> + klp_update_patch_state(current); >> + >> if (thread_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) >> do_signal(regs); > > The rest should be fine. > Thanks! Madhavan _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel