From patchwork Mon Jan 23 13:46:01 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Rutland X-Patchwork-Id: 13112242 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 66D06C38142 for ; Mon, 23 Jan 2023 13:49:42 +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:References:In-Reply-To: Message-Id:Date: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=V0gFpbMJJBE60ojAbIkCKSiFbJqHSRsfN6Icm8PVtl4=; b=4SlrA5Oa0ZXlhd Rf0qi1DNt8oD1J2uW7mwWUZL4JPYCnB4YEsUt2wV6SwU6uHHNf2UcORye43JtQjy4WCaOr0t7UJ+i xUC3Dpahh6b/7whHMr2N/ZksxrvTBbsbYMB/h/6TUQYeU+0Y0zkVtcA/dxOIqZCubiBct4ai0mQiI llNpzYj9rCIgFeDX64Ka00reTm/2+fqwKcy5OeXobfQK4frheqfryHdxaoJuxxIEl4/tY2bm/AG6z d/0r9yHX7tXEfKfi75QcxNp7plcJa0FZeB7ux49a6GYW7FFdewEUydhuKPf/bqobk/AvF/LMz740d 8TrLUklcHxv0dY2ngoyQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pJxBb-00HQDc-37; Mon, 23 Jan 2023 13:48:35 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pJx9Y-00HPG6-0X for linux-arm-kernel@lists.infradead.org; Mon, 23 Jan 2023 13:46:29 +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 5BCE6165C; Mon, 23 Jan 2023 05:47:09 -0800 (PST) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id C5A4D3F64C; Mon, 23 Jan 2023 05:46:25 -0800 (PST) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org Cc: catalin.marinas@arm.com, lenb@kernel.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, mark.rutland@arm.com, mhiramat@kernel.org, ndesaulniers@google.com, ojeda@kernel.org, peterz@infradead.org, rafael.j.wysocki@intel.com, revest@chromium.org, robert.moore@intel.com, rostedt@goodmis.org, will@kernel.org Subject: [PATCH v3 6/8] arm64: patching: Add aarch64_insn_write_literal_u64() Date: Mon, 23 Jan 2023 13:46:01 +0000 Message-Id: <20230123134603.1064407-7-mark.rutland@arm.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230123134603.1064407-1-mark.rutland@arm.com> References: <20230123134603.1064407-1-mark.rutland@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230123_054628_180167_FA4D3BC2 X-CRM114-Status: UNSURE ( 9.67 ) X-CRM114-Notice: Please train this message. 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 In subsequent patches we'll need to atomically write to a naturally-aligned 64-bit literal embedded within the kernel text. Add a helper for this. For consistency with other text patching code we use copy_to_kernel_nofault(), which is atomic for naturally-aligned accesses up to 64-bits. Signed-off-by: Mark Rutland Cc: Catalin Marinas Cc: Florent Revest Cc: Masami Hiramatsu Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Will Deacon --- arch/arm64/include/asm/patching.h | 2 ++ arch/arm64/kernel/patching.c | 17 +++++++++++++++++ 2 files changed, 19 insertions(+) diff --git a/arch/arm64/include/asm/patching.h b/arch/arm64/include/asm/patching.h index 6bf5adc56295..68908b82b168 100644 --- a/arch/arm64/include/asm/patching.h +++ b/arch/arm64/include/asm/patching.h @@ -7,6 +7,8 @@ int aarch64_insn_read(void *addr, u32 *insnp); int aarch64_insn_write(void *addr, u32 insn); +int aarch64_insn_write_literal_u64(void *addr, u64 val); + int aarch64_insn_patch_text_nosync(void *addr, u32 insn); int aarch64_insn_patch_text(void *addrs[], u32 insns[], int cnt); diff --git a/arch/arm64/kernel/patching.c b/arch/arm64/kernel/patching.c index 33e0fabc0b79..b4835f6d594b 100644 --- a/arch/arm64/kernel/patching.c +++ b/arch/arm64/kernel/patching.c @@ -88,6 +88,23 @@ int __kprobes aarch64_insn_write(void *addr, u32 insn) return __aarch64_insn_write(addr, cpu_to_le32(insn)); } +noinstr int aarch64_insn_write_literal_u64(void *addr, u64 val) +{ + u64 *waddr; + unsigned long flags; + int ret; + + raw_spin_lock_irqsave(&patch_lock, flags); + waddr = patch_map(addr, FIX_TEXT_POKE0); + + ret = copy_to_kernel_nofault(waddr, &val, sizeof(val)); + + patch_unmap(FIX_TEXT_POKE0); + raw_spin_unlock_irqrestore(&patch_lock, flags); + + return ret; +} + int __kprobes aarch64_insn_patch_text_nosync(void *addr, u32 insn) { u32 *tp = addr;