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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F30E0C4332F for ; Mon, 13 Dec 2021 08:57:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233462AbhLMI53 (ORCPT ); Mon, 13 Dec 2021 03:57:29 -0500 Received: from mailgw01.mediatek.com ([60.244.123.138]:46392 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S233443AbhLMI5Z (ORCPT ); Mon, 13 Dec 2021 03:57:25 -0500 X-UUID: aa3e7304b7e74dfe86d2c5b143814ee6-20211213 X-UUID: aa3e7304b7e74dfe86d2c5b143814ee6-20211213 Received: from mtkcas11.mediatek.inc [(172.21.101.40)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1386785207; Mon, 13 Dec 2021 16:57:21 +0800 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.3; Mon, 13 Dec 2021 16:57:20 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Mon, 13 Dec 2021 16:57:20 +0800 From: Mark-PK Tsai To: CC: , , , , , , , , , , Subject: [PATCH 5.4 4/5] arm: extend pfn_valid to take into account freed memory map alignment Date: Mon, 13 Dec 2021 16:57:09 +0800 Message-ID: <20211213085710.28962-5-mark-pk.tsai@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20211213085710.28962-1-mark-pk.tsai@mediatek.com> References: <20211213085710.28962-1-mark-pk.tsai@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mike Rapoport commit a4d5613c4dc6d413e0733e37db9d116a2a36b9f3 upstream. When unused memory map is freed the preserved part of the memory map is extended to match pageblock boundaries because lots of core mm functionality relies on homogeneity of the memory map within pageblock boundaries. Since pfn_valid() is used to check whether there is a valid memory map entry for a PFN, make it return true also for PFNs that have memory map entries even if there is no actual memory populated there. Signed-off-by: Mike Rapoport Tested-by: Kefeng Wang Tested-by: Tony Lindgren Link: https://lore.kernel.org/lkml/20210630071211.21011-1-rppt@kernel.org/ Signed-off-by: Mark-PK Tsai --- arch/arm/mm/init.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index c0e70e643f92..c30b4b2f8de9 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -176,11 +176,22 @@ static void __init zone_sizes_init(unsigned long min, unsigned long max_low, int pfn_valid(unsigned long pfn) { phys_addr_t addr = __pfn_to_phys(pfn); + unsigned long pageblock_size = PAGE_SIZE * pageblock_nr_pages; if (__phys_to_pfn(addr) != pfn) return 0; - return memblock_is_map_memory(__pfn_to_phys(pfn)); + /* + * If address less than pageblock_size bytes away from a present + * memory chunk there still will be a memory map entry for it + * because we round freed memory map to the pageblock boundaries. + */ + if (memblock_overlaps_region(&memblock.memory, + ALIGN_DOWN(addr, pageblock_size), + pageblock_size)) + return 1; + + return 0; } EXPORT_SYMBOL(pfn_valid); #endif -- 2.18.0