From patchwork Tue Oct 31 15:38:29 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Morse X-Patchwork-Id: 10034809 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 5CEAD60291 for ; Tue, 31 Oct 2017 15:42:30 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4EAF928BF7 for ; Tue, 31 Oct 2017 15:42:30 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 4342728BFE; Tue, 31 Oct 2017 15:42:30 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 15E9828BF7 for ; Tue, 31 Oct 2017 15:42:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.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=Ctyc20ZvM+9w7XIG9siRh04zap1LCLWHpuZrS4JdTis=; b=PVh/Vu2eEkZDI296AIcONqJ5aU Xbvt1GQrznpVXIJ38jjQDaGJ9DrR4eVxXOpxjcSBFvdi7CmpAGrm9dNOnxspnvW/r9kJP4YM0Ts5Z xrCsgyumZ9nm0jgKeRKySjHkyuIMvT1cdTLm0K9mv1zM2AIXgSdpDXeVnmqt3XLpjxLsRn8SMQ2xw ZT5vkfJZbMZP4Eq/6qA0wDxFIFkzAXl9TYDK5nhYuC4nybFMwEAPJcOXfNb/k4Uv/9ekbNXcZ37fg urdIQvPvb6eU4PrssGP/8x9WaJ54SKvlChldiPy1VEAkBnk62SgJnMVFHP+ur2WZykIxrBiVX8lG8 lETVqiHw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1e9YgO-0005mc-2v; Tue, 31 Oct 2017 15:42:28 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1e9Yez-0004qZ-Py for linux-arm-kernel@lists.infradead.org; Tue, 31 Oct 2017 15:41:21 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D7F8115BF; Tue, 31 Oct 2017 08:40:42 -0700 (PDT) Received: from melchizedek.cambridge.arm.com (melchizedek.cambridge.arm.com [10.1.207.55]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id D16503F24A; Tue, 31 Oct 2017 08:40:39 -0700 (PDT) From: James Morse To: linux-acpi@vger.kernel.org Subject: [RFC/RFT PATCH 3/6] ACPI / APEI: Replace ioremap_page_range() with fixmap Date: Tue, 31 Oct 2017 15:38:29 +0000 Message-Id: <20171031153832.17746-4-james.morse@arm.com> X-Mailer: git-send-email 2.15.0.rc2 In-Reply-To: <20171031153832.17746-1-james.morse@arm.com> References: <20171031153832.17746-1-james.morse@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20171031_084102_304066_4EC60303 X-CRM114-Status: GOOD ( 14.41 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Rafael J . Wysocki" , Tony Luck , Xie XiuQi , Tyler Baicar , Catalin Marinas , x86@kernel.org, Will Deacon , linux-kernel@vger.kernel.org, Dongjiu Geng , Ingo Molnar , James Morse , "H . Peter Anvin" , Thomas Gleixner , Borislav Petkov , torvalds@linux-foundation.org, linux-arm-kernel@lists.infradead.org, Len Brown MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Replace ghes_io{re,un}map_pfn_{nmi,irq}()s use of ioremap_page_range() with __set_fixmap() as ioremap_page_range() may sleep to allocate a new level of page-table, even if its passed an existing final-address to use in the mapping. clear_fixmap() does the TLB invalidation in __set_fixmap() for arm64 and __set_pte_vaddr() for x86. In each case its the same as the respective arch_apei_flush_tlb_one(). Reported-by: Fengguang Wu Suggested-by: Linus Torvalds Signed-off-by: James Morse CC: Tyler Baicar CC: Dongjiu Geng CC: Xie XiuQi Reviewed-by: Borislav Petkov Tested-by: Qiang Zheng --- CC'd people I've seen posting CPER log fragments, could you give this a test on your platforms? drivers/acpi/apei/ghes.c | 45 +++++++++++++++------------------------------ 1 file changed, 15 insertions(+), 30 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 3c3a37b8503b..f3269816b997 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -51,6 +51,7 @@ #include #include #include +#include #include #include @@ -112,7 +113,7 @@ static DEFINE_MUTEX(ghes_list_mutex); * Because the memory area used to transfer hardware error information * from BIOS to Linux can be determined only in NMI, IRQ or timer * handler, but general ioremap can not be used in atomic context, so - * a special version of atomic ioremap is implemented for that. + * the fixmap is used instead. */ /* @@ -126,8 +127,8 @@ static DEFINE_MUTEX(ghes_list_mutex); /* virtual memory area for atomic ioremap */ static struct vm_struct *ghes_ioremap_area; /* - * These 2 spinlock is used to prevent atomic ioremap virtual memory - * area from being mapped simultaneously. + * These 2 spinlocks are used to prevent the fixmap entries from being used + * simultaneously. */ static DEFINE_RAW_SPINLOCK(ghes_ioremap_lock_nmi); static DEFINE_SPINLOCK(ghes_ioremap_lock_irq); @@ -159,52 +160,36 @@ static void ghes_ioremap_exit(void) static void __iomem *ghes_ioremap_pfn_nmi(u64 pfn) { - unsigned long vaddr; phys_addr_t paddr; pgprot_t prot; - vaddr = (unsigned long)GHES_IOREMAP_NMI_PAGE(ghes_ioremap_area->addr); - paddr = pfn << PAGE_SHIFT; prot = arch_apei_get_mem_attribute(paddr); - ioremap_page_range(vaddr, vaddr + PAGE_SIZE, paddr, prot); + __set_fixmap(FIX_APEI_GHES_NMI, paddr, prot); - return (void __iomem *)vaddr; + return (void __iomem *) fix_to_virt(FIX_APEI_GHES_NMI); } static void __iomem *ghes_ioremap_pfn_irq(u64 pfn) { - unsigned long vaddr, paddr; + unsigned long paddr; pgprot_t prot; - vaddr = (unsigned long)GHES_IOREMAP_IRQ_PAGE(ghes_ioremap_area->addr); - paddr = pfn << PAGE_SHIFT; prot = arch_apei_get_mem_attribute(paddr); + __set_fixmap(FIX_APEI_GHES_IRQ, paddr, prot); - ioremap_page_range(vaddr, vaddr + PAGE_SIZE, paddr, prot); - - return (void __iomem *)vaddr; + return (void __iomem *) fix_to_virt(FIX_APEI_GHES_IRQ); } -static void ghes_iounmap_nmi(void __iomem *vaddr_ptr) +static void ghes_iounmap_nmi(void) { - unsigned long vaddr = (unsigned long __force)vaddr_ptr; - void *base = ghes_ioremap_area->addr; - - BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_NMI_PAGE(base)); - unmap_kernel_range_noflush(vaddr, PAGE_SIZE); - arch_apei_flush_tlb_one(vaddr); + clear_fixmap(FIX_APEI_GHES_NMI); } -static void ghes_iounmap_irq(void __iomem *vaddr_ptr) +static void ghes_iounmap_irq(void) { - unsigned long vaddr = (unsigned long __force)vaddr_ptr; - void *base = ghes_ioremap_area->addr; - - BUG_ON(vaddr != (unsigned long)GHES_IOREMAP_IRQ_PAGE(base)); - unmap_kernel_range_noflush(vaddr, PAGE_SIZE); - arch_apei_flush_tlb_one(vaddr); + clear_fixmap(FIX_APEI_GHES_IRQ); } static int ghes_estatus_pool_init(void) @@ -360,10 +345,10 @@ static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len, paddr += trunk; buffer += trunk; if (in_nmi) { - ghes_iounmap_nmi(vaddr); + ghes_iounmap_nmi(); raw_spin_unlock(&ghes_ioremap_lock_nmi); } else { - ghes_iounmap_irq(vaddr); + ghes_iounmap_irq(); spin_unlock_irqrestore(&ghes_ioremap_lock_irq, flags); } }