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 X-Spam-Level: X-Spam-Status: No, score=-11.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61CF8C43461 for ; Thu, 17 Sep 2020 14:23:55 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EDFE12075B for ; Thu, 17 Sep 2020 14:23:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="faARdzhy" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EDFE12075B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=TqdUMgbN269r2Hx5saHSTv7quPPl33Xy2J9ch416w7s=; b=faARdzhySELzNArcmr2gVtUPy hFi7n8a1lj/w2MqbY8GM82HxkH5ZNlWr889b1Mz38Ka47/mdn0x3twn2qdbReVSBewguUt9WmClBY vx7LYkY4Cw5jgNNSp98Ssxazet7gcpSO1tiDs2RVI9FqT6yhPH7UvK+K1fzATT7tQ/jsIhGf03yoK bF2QdvBUD8d14Plk1fu3CEVGeGN2vio4aQF878qs29es0G4QXvqUeKn3b3G+dWqzcQj9N+vtxXM6H T5/yb2QTzGzJSrm1WKj6YdDq3H7+GznYMmJ5XzdXo09bDlU88KvQpT3XGWAJff72qKfCKU8mTKYTT HP1AXYGtQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kIuni-0002Im-NF; Thu, 17 Sep 2020 14:22:18 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kIunf-0002IH-VZ for linux-arm-kernel@lists.infradead.org; Thu, 17 Sep 2020 14:22:16 +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 29BCF12FC; Thu, 17 Sep 2020 07:22:14 -0700 (PDT) Received: from [192.168.1.190] (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 18E6F3F718; Thu, 17 Sep 2020 07:22:11 -0700 (PDT) Subject: Re: [PATCH v2 24/37] arm64: mte: Add in-kernel tag fault handler To: Catalin Marinas , Andrey Konovalov References: <7866d9e6f11f12f1bad42c895bf4947addba71c2.1600204505.git.andreyknvl@google.com> <20200917140337.GC10662@gaia> From: Vincenzo Frascino Message-ID: <48ef25ff-0d06-54d9-b467-ff068465e3dc@arm.com> Date: Thu, 17 Sep 2020 15:24:39 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200917140337.GC10662@gaia> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200917_102216_055337_4F5C3439 X-CRM114-Status: GOOD ( 21.22 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arm-kernel@lists.infradead.org, Marco Elver , Elena Petrova , Kevin Brodsky , Will Deacon , Branislav Rankov , kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Alexander Potapenko , Dmitry Vyukov , Andrey Ryabinin , Andrew Morton , Evgenii Stepanov 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 On 9/17/20 3:03 PM, Catalin Marinas wrote: > On Tue, Sep 15, 2020 at 11:16:06PM +0200, Andrey Konovalov wrote: >> diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c >> index a3bd189602df..cdc23662691c 100644 >> --- a/arch/arm64/mm/fault.c >> +++ b/arch/arm64/mm/fault.c >> @@ -294,6 +295,18 @@ static void die_kernel_fault(const char *msg, unsigned long addr, >> do_exit(SIGKILL); >> } >> >> +static void report_tag_fault(unsigned long addr, unsigned int esr, >> + struct pt_regs *regs) >> +{ >> + bool is_write = ((esr & ESR_ELx_WNR) >> ESR_ELx_WNR_SHIFT) != 0; >> + >> + pr_alert("Memory Tagging Extension Fault in %pS\n", (void *)regs->pc); >> + pr_alert(" %s at address %lx\n", is_write ? "Write" : "Read", addr); >> + pr_alert(" Pointer tag: [%02x], memory tag: [%02x]\n", >> + mte_get_ptr_tag(addr), >> + mte_get_mem_tag((void *)addr)); >> +} >> + >> static void __do_kernel_fault(unsigned long addr, unsigned int esr, >> struct pt_regs *regs) >> { >> @@ -641,10 +654,31 @@ static int do_sea(unsigned long addr, unsigned int esr, struct pt_regs *regs) >> return 0; >> } >> >> +static void do_tag_recovery(unsigned long addr, unsigned int esr, >> + struct pt_regs *regs) >> +{ >> + report_tag_fault(addr, esr, regs); > > I'd only report this once since we expect it to be disabled lazily on > the other CPUs (i.e. just use a "static bool reported" to keep track). > Ok, I will fix it in the next version. >> + >> + /* >> + * Disable Memory Tagging Extension Tag Checking on the local CPU > > Too verbose, just say MTE tag checking, people reading this code should > have learnt already what MTE stands for ;). > All right, will change it ;) >> + * for the current EL. >> + * It will be done lazily on the other CPUs when they will hit a >> + * tag fault. >> + */ >> + sysreg_clear_set(sctlr_el1, SCTLR_ELx_TCF_MASK, SCTLR_ELx_TCF_NONE); >> + isb(); >> +} >> + >> + >> static int do_tag_check_fault(unsigned long addr, unsigned int esr, >> struct pt_regs *regs) >> { >> - do_bad_area(addr, esr, regs); >> + /* The tag check fault (TCF) is per TTBR */ >> + if (is_ttbr0_addr(addr)) >> + do_bad_area(addr, esr, regs); >> + else >> + do_tag_recovery(addr, esr, regs); > > This part looks fine now. > Ok, thanks. -- Regards, Vincenzo _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel