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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 48B81ECDE43 for ; Fri, 19 Oct 2018 04:20:03 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 A540B2145D for ; Fri, 19 Oct 2018 04:20:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A540B2145D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 42bt404j2QzF3XW for ; Fri, 19 Oct 2018 15:20:00 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 42bswk0DGCzF3St for ; Fri, 19 Oct 2018 15:13:42 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Received: by ozlabs.org (Postfix) id 42bswj6lTrz9sCm; Fri, 19 Oct 2018 15:13:41 +1100 (AEDT) Received: by ozlabs.org (Postfix, from userid 1034) id 42bswj6R70z9sDJ; Fri, 19 Oct 2018 15:13:41 +1100 (AEDT) From: Michael Ellerman To: linuxppc-dev@ozlabs.org Subject: [PATCH 3/6] powerpc/mm/radix: Fix small page at boundary when splitting Date: Fri, 19 Oct 2018 15:13:31 +1100 Message-Id: <20181019041334.4945-3-mpe@ellerman.id.au> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20181019041334.4945-1-mpe@ellerman.id.au> References: <20181019041334.4945-1-mpe@ellerman.id.au> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: aneesh.kumar@linux.vnet.ibm.com Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" When we have CONFIG_STRICT_KERNEL_RWX enabled, we want to split the linear mapping at the text/data boundary so we can map the kernel text read only. Currently we always use a small page at the text/data boundary, even when that's not necessary: Mapped 0x0000000000000000-0x0000000000e00000 with 2.00 MiB pages Mapped 0x0000000000e00000-0x0000000001000000 with 64.0 KiB pages Mapped 0x0000000001000000-0x0000000040000000 with 2.00 MiB pages This is because the check that the mapping crosses the __init_begin boundary is too strict, it also returns true when we map exactly up to the boundary. So fix it to check that the mapping would actually map past __init_begin, and with that we see: Mapped 0x0000000000000000-0x0000000040000000 with 2.00 MiB pages Mapped 0x0000000040000000-0x0000000100000000 with 1.00 GiB pages Signed-off-by: Michael Ellerman --- arch/powerpc/mm/pgtable-radix.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c index bb85c58b96c8..7a44ec276290 100644 --- a/arch/powerpc/mm/pgtable-radix.c +++ b/arch/powerpc/mm/pgtable-radix.c @@ -295,14 +295,14 @@ static int __meminit create_physical_mapping(unsigned long start, if (split_text_mapping && (mapping_size == PUD_SIZE) && (addr < __pa_symbol(__init_begin)) && - (addr + mapping_size) >= __pa_symbol(__init_begin)) { + (addr + mapping_size) > __pa_symbol(__init_begin)) { max_mapping_size = PMD_SIZE; goto retry; } if (split_text_mapping && (mapping_size == PMD_SIZE) && (addr < __pa_symbol(__init_begin)) && - (addr + mapping_size) >= __pa_symbol(__init_begin)) { + (addr + mapping_size) > __pa_symbol(__init_begin)) { mapping_size = PAGE_SIZE; psize = mmu_virtual_psize; } -- 2.17.2