From patchwork Fri Feb 23 06:36:08 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Yongqiang Liu X-Patchwork-Id: 13568578 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 A97F0C5478C for ; Fri, 23 Feb 2024 06:37:04 +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: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:In-Reply-To:References: List-Owner; bh=ErVto6cW60o90GweiVDqM2PHuo68nxdb0IRIlzbpwkg=; b=wj5k6MxG5zun8W gWTvV52YdT4O5q042n5K+WbOj90hFffqPJ51J9xkxl1nuXKneilfpvx4aCyAOemEPDusBlMPscKLB kr7QTJOJ0nFQ9fkkHGkpxFFeNGjVueWMrEE3OENf2bVMwQydNNdRjYA5aJSB/QUfl4zo9eJPwSpD+ uVxPwrKSWrMg6tZdLxPTDhisDoSdjrKgfWA9immG0afmxD+48s4AhAlnrUcxGxVUfwRu3XD4c33yy MTCgFkk2rtWGGL21YTizudJbx6pS3MyEZbVSHkwmCpUcnO2bNk6N3FNmE4Dq+3zUz5H+NdoQ23iKQ CmdMoSqW8Ql8wdYET/fA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rdPAg-00000008BWJ-1gAx; Fri, 23 Feb 2024 06:36:39 +0000 Received: from szxga04-in.huawei.com ([45.249.212.190]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rdPAQ-00000008BMe-1XuU for linux-arm-kernel@lists.infradead.org; Fri, 23 Feb 2024 06:36:22 +0000 Received: from mail.maildlp.com (unknown [172.19.88.214]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4Th0bC23Vqz2BdKl; Fri, 23 Feb 2024 14:33:59 +0800 (CST) Received: from dggpeml500005.china.huawei.com (unknown [7.185.36.59]) by mail.maildlp.com (Postfix) with ESMTPS id C195B1A016B; Fri, 23 Feb 2024 14:36:09 +0800 (CST) Received: from huawei.com (10.175.112.125) by dggpeml500005.china.huawei.com (7.185.36.59) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.35; Fri, 23 Feb 2024 14:36:09 +0800 From: Yongqiang Liu To: CC: , , , , , , , , , , , Subject: [PATCH v2] arm: flush: check if the folio is reserved for no-mapping addresses Date: Fri, 23 Feb 2024 14:36:08 +0800 Message-ID: <20240223063608.2605736-1-liuyongqiang13@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Originating-IP: [10.175.112.125] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To dggpeml500005.china.huawei.com (7.185.36.59) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240222_223618_624433_1B51C8FD X-CRM114-Status: GOOD ( 11.75 ) 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 Since commit a4d5613c4dc6 ("arm: extend pfn_valid to take into account freed memory map alignment") changes the semantics of pfn_valid() to check presence of the memory map for a PFN. A valid page for an address which is reserved but not mapped by the kernel[1], the system crashed during some uio test with the following memory layout: node 0: [mem 0x00000000c0a00000-0x00000000cc8fffff] node 0: [mem 0x00000000d0000000-0x00000000da1fffff] the uio layout is：0xc0900000, 0x100000 the crash backtrace like: Unable to handle kernel paging request at virtual address bff00000 [...] CPU: 1 PID: 465 Comm: startapp.bin Tainted: G O 5.10.0 #1 Hardware name: Generic DT based system PC is at b15_flush_kern_dcache_area+0x24/0x3c LR is at __sync_icache_dcache+0x6c/0x98 [...] (b15_flush_kern_dcache_area) from (__sync_icache_dcache+0x6c/0x98) (__sync_icache_dcache) from (set_pte_at+0x28/0x54) (set_pte_at) from (remap_pfn_range+0x1a0/0x274) (remap_pfn_range) from (uio_mmap+0x184/0x1b8 [uio]) (uio_mmap [uio]) from (__mmap_region+0x264/0x5f4) (__mmap_region) from (__do_mmap_mm+0x3ec/0x440) (__do_mmap_mm) from (do_mmap+0x50/0x58) (do_mmap) from (vm_mmap_pgoff+0xfc/0x188) (vm_mmap_pgoff) from (ksys_mmap_pgoff+0xac/0xc4) (ksys_mmap_pgoff) from (ret_fast_syscall+0x0/0x5c) Code: e0801001 e2423001 e1c00003 f57ff04f (ee070f3e) ---[ end trace 09cf0734c3805d52 ]--- Kernel panic - not syncing: Fatal exception So check if PG_reserved was set to solve this issue. [1]: https://lore.kernel.org/lkml/Zbtdue57RO0QScJM@linux.ibm.com/ Fixes: a4d5613c4dc6 ("arm: extend pfn_valid to take into account freed memory map alignment") Suggested-by: Mike Rapoport Signed-off-by: Yongqiang Liu --- v1 -> v2 - Improve commit message - Use helpers instead of PG_reserved - drop the unnecessary include headers arch/arm/mm/flush.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/arm/mm/flush.c b/arch/arm/mm/flush.c index d19d140a10c7..0749cf8a6637 100644 --- a/arch/arm/mm/flush.c +++ b/arch/arm/mm/flush.c @@ -296,6 +296,9 @@ void __sync_icache_dcache(pte_t pteval) return; folio = page_folio(pfn_to_page(pfn)); + if (folio_test_reserved(folio)) + return; + if (cache_is_vipt_aliasing()) mapping = folio_flush_mapping(folio); else