From patchwork Wed Apr 5 13:37:15 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Punit Agrawal X-Patchwork-Id: 9664131 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 5995E602B5 for ; Wed, 5 Apr 2017 13:51:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 47E4226E4E for ; Wed, 5 Apr 2017 13:51:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3C5AC28535; Wed, 5 Apr 2017 13:51:17 +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=-1.9 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID autolearn=ham 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 B6CAE26E4E for ; Wed, 5 Apr 2017 13:51:16 +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=ezaoUrUtlTXp632z5JT3FVW81XXWIxkH/tcDgcL70eE=; b=l4j1hkDi6uHnwvBfSuhg3/Ju9r V9xWVgNSEHnnAEWGgkpZSnAc8xUdpaLQoFp92RWO07bBBITf96dDXpOOiqCZI+iaFYlID9xpmhA1F ghrRn/FHCpXBpL59ISRK+09fW/4bZ0MCnbGNf64xy+9iADRJluG5OuwEvpjf5UVdA4EnZVY+f8glK 4ykPdUtAkCWKG+fTrfmiu/nWalWB4o1GatAIf9/TYLVzxHleuy+SmUW/iAGHbpovLOhwjNGhmNOeu CVM5k9QdCIvx8NbdhIvk1edeD0FgZpiMZ62BmPl1FzFlMlEnkbLvknXXcFlwSI8vBpL5v90e1KLtb /e+57dmA==; 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 1cvlL8-0002Gr-Kz; Wed, 05 Apr 2017 13:51:14 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1cvl8c-0003dc-Qf for linux-arm-kernel@lists.infradead.org; Wed, 05 Apr 2017 13:38:20 +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 D66A928; Wed, 5 Apr 2017 06:38:02 -0700 (PDT) Received: from localhost (e105922-lin.cambridge.arm.com [10.1.195.42]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A5E443F3E1; Wed, 5 Apr 2017 06:38:02 -0700 (PDT) From: Punit Agrawal To: catalin.marinas@arm.com, will.deacon@arm.com, akpm@linux-foundation.org, mark.rutland@arm.com Subject: [PATCH v2 2/9] arm64: hugetlbpages: Support handling swap entries in huge_pte_offset() Date: Wed, 5 Apr 2017 14:37:15 +0100 Message-Id: <20170405133722.6406-3-punit.agrawal@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170405133722.6406-1-punit.agrawal@arm.com> References: <20170405133722.6406-1-punit.agrawal@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20170405_063819_045672_426FD74E X-CRM114-Status: GOOD ( 11.24 ) 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: hillf.zj@alibaba-inc.com, David Woods , Punit Agrawal , steve.capper@arm.com, tbaicar@codeaurora.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, kirill.shutemov@linux.intel.com, mike.kravetz@oracle.com 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 huge_pte_offset() does not correctly handle poisoned or migration page table entries. It returns NULL instead of the offset when it encounters a swap entry. This leads to errors such as [ 344.165544] mm/pgtable-generic.c:33: bad pmd 000000083af00074. in the kernel log when unmapping memory on process exit. huge_pte_offset() is now provided with the size of the hugepage being accessed. Use the size to find the correct page table entry to return. Signed-off-by: Punit Agrawal Cc: David Woods --- arch/arm64/mm/hugetlbpage.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index 1bc08ae49e6a..009648c4500f 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -194,36 +194,36 @@ pte_t *huge_pte_offset(struct mm_struct *mm, { pgd_t *pgd; pud_t *pud; - pmd_t *pmd = NULL; - pte_t *pte = NULL; + pmd_t *pmd; + pte_t *pte; pgd = pgd_offset(mm, addr); pr_debug("%s: addr:0x%lx pgd:%p\n", __func__, addr, pgd); if (!pgd_present(*pgd)) return NULL; + pud = pud_offset(pgd, addr); - if (!pud_present(*pud)) + if (pud_none(*pud) && sz != PUD_SIZE) return NULL; - - if (pud_huge(*pud)) + else if (!pud_table(*pud)) return (pte_t *)pud; + + if (sz == CONT_PMD_SIZE) + addr &= CONT_PMD_MASK; + pmd = pmd_offset(pud, addr); - if (!pmd_present(*pmd)) + if (pmd_none(*pmd) && + !(sz == PMD_SIZE || sz == CONT_PMD_SIZE)) return NULL; - - if (pte_cont(pmd_pte(*pmd))) { - pmd = pmd_offset( - pud, (addr & CONT_PMD_MASK)); - return (pte_t *)pmd; - } - if (pmd_huge(*pmd)) + else if (!pmd_table(*pmd)) return (pte_t *)pmd; - pte = pte_offset_kernel(pmd, addr); - if (pte_present(*pte) && pte_cont(*pte)) { + + if (sz == CONT_PTE_SIZE) { pte = pte_offset_kernel( pmd, (addr & CONT_PTE_MASK)); return pte; } + return NULL; }