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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 638F8C388F7 for ; Fri, 13 Nov 2020 12:51:58 +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 07601206D9 for ; Fri, 13 Nov 2020 12:51:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="bUPQ8Bi5" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 07601206D9 Authentication-Results: mail.kernel.org; dmarc=fail (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:MIME-Version:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:References:In-Reply-To:Message-Id:Date:Subject:To: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ZTfGG99we6j1RWjoVEKsrbWIXNtAHpQUMbD2/dVyxrU=; b=bUPQ8Bi5TfVUBxmRbnal47hMOp MwqfdMZZf9KGuZQQZNtyOHNTMFtVHRfEaCGkHoMlmBRUktDxUOZSEbF9Du4+H36e2YPONaU9bLbVw 1Gw5bU7nomKYNbXPzgECuQzBuowLNSiVnw4uqq0p0SV1PsL7+7Iwu0oV4SpFn8V2TdIaBVFi12lVs ak9QTMfK6Nadi2lZV9a3xxxN70yPOatDzxvueA/H1TU8HVQJ+reYQWIaIo7qCt8eCFs3883M7yxFL LnmR8ADzT8zGA7+kfs2Ib6r2rWgQjlXwmfeNc8JHGEEwpCSaw7hpxR/tT8obuQ9e2PVmSzTEYbvJ5 grxrhW7Q==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kdYX9-0006Q7-Vu; Fri, 13 Nov 2020 12:50:32 +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 1kdYWY-0006Cv-G4 for linux-arm-kernel@lists.infradead.org; Fri, 13 Nov 2020 12:49:55 +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 D83051534; Fri, 13 Nov 2020 04:49:53 -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 D8D2B3F6CF; Fri, 13 Nov 2020 04:49:52 -0800 (PST) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, will@kernel.org Subject: [PATCHv4 06/17] arm64: sdei: move uaccess logic to arch/arm64/ Date: Fri, 13 Nov 2020 12:49:26 +0000 Message-Id: <20201113124937.20574-7-mark.rutland@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20201113124937.20574-1-mark.rutland@arm.com> References: <20201113124937.20574-1-mark.rutland@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201113_074954_678019_A36FC01D X-CRM114-Status: GOOD ( 16.57 ) 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: mark.rutland@arm.com, robin.murphy@arm.com, james.morse@arm.com, hch@lst.de MIME-Version: 1.0 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 The SDEI support code is split across arch/arm64/ and drivers/firmware/, largley this is split so that the arch-specific portions are under arch/arm64, and the management logic is under drivers/firmware/. However, exception entry fixups are currently under drivers/firmware. Let's move the exception entry fixups under arch/arm64/. This de-clutters the management logic, and puts all the arch-specific portions in one place. Doing this also allows the fixups to be applied earlier, so things like PAN and UAO will be in a known good state before we run other logic. This will also make subsequent refactoring easier. Signed-off-by: Mark Rutland Cc: Catalin Marinas Cc: Christoph Hellwig Cc: James Morse Cc: Will Deacon --- arch/arm64/kernel/sdei.c | 18 ++++++++++++------ drivers/firmware/arm_sdei.c | 14 -------------- 2 files changed, 12 insertions(+), 20 deletions(-) diff --git a/arch/arm64/kernel/sdei.c b/arch/arm64/kernel/sdei.c index 7689f2031c0c..4a5f24602aa0 100644 --- a/arch/arm64/kernel/sdei.c +++ b/arch/arm64/kernel/sdei.c @@ -178,12 +178,6 @@ static __kprobes unsigned long _sdei_handler(struct pt_regs *regs, sdei_api_event_context(i, ®s->regs[i]); } - /* - * We didn't take an exception to get here, set PAN. UAO will be cleared - * by sdei_event_handler()s force_uaccess_begin() call. - */ - __uaccess_enable_hw_pan(); - err = sdei_event_handler(regs, arg); if (err) return SDEI_EV_FAILED; @@ -227,6 +221,16 @@ asmlinkage __kprobes notrace unsigned long __sdei_handler(struct pt_regs *regs, struct sdei_registered_event *arg) { unsigned long ret; + mm_segment_t orig_addr_limit; + + /* + * We didn't take an exception to get here, so the HW hasn't set PAN or + * cleared UAO, and the exception entry code hasn't reset addr_limit. + * Set PAN, then use force_uaccess_begin() to clear UAO and reset + * addr_limit. + */ + __uaccess_enable_hw_pan(); + orig_addr_limit = force_uaccess_begin(); nmi_enter(); @@ -234,5 +238,7 @@ __sdei_handler(struct pt_regs *regs, struct sdei_registered_event *arg) nmi_exit(); + force_uaccess_end(orig_addr_limit); + return ret; } diff --git a/drivers/firmware/arm_sdei.c b/drivers/firmware/arm_sdei.c index 840754dcc6ca..a7e762c352f9 100644 --- a/drivers/firmware/arm_sdei.c +++ b/drivers/firmware/arm_sdei.c @@ -31,7 +31,6 @@ #include #include #include -#include /* * The call to use to reach the firmware. @@ -1092,26 +1091,13 @@ int sdei_event_handler(struct pt_regs *regs, struct sdei_registered_event *arg) { int err; - mm_segment_t orig_addr_limit; u32 event_num = arg->event_num; - /* - * Save restore 'fs'. - * The architecture's entry code save/restores 'fs' when taking an - * exception from the kernel. This ensures addr_limit isn't inherited - * if you interrupted something that allowed the uaccess routines to - * access kernel memory. - * Do the same here because this doesn't come via the same entry code. - */ - orig_addr_limit = force_uaccess_begin(); - err = arg->callback(event_num, regs, arg->callback_arg); if (err) pr_err_ratelimited("event %u on CPU %u failed with error: %d\n", event_num, smp_processor_id(), err); - force_uaccess_end(orig_addr_limit); - return err; } NOKPROBE_SYMBOL(sdei_event_handler); -- 2.11.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel