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 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 70745C56208 for ; Thu, 6 Aug 2026 09:35:55 +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=42zLC2o63fdGj6SjHnEN1/VNKqroAIrDu8wlrrzCV4s=; b=Ar8mniQGoj3Yug rsKzhE7jy0sTy69HoM9sdK9f8UzQikRDeqTBZ3z/NzIFEX3ZL8JylZ4Clo0EXtmzykpLu6jhZY/OM AI8IvJVDAdrfPjE1yS5038UTqAkKWVDr+ym8QHGXlN7yDZ+Jqm9HDqPMsjVWCmOVGmrmWURMtUUMj rYGLg9ROsiSdmYI3VeK8+u+FAoahnAHeUwdqUkZwPBZ3oRPOi8GIFGa0GQ8bkUWeII/9uE/s+e4+C GpYTgM4rocVYeEbwOO4jKNKLaWJX5pIWTp2UcfKAe34b+SiQrUBLBTrwERUBodBplNy7ZulDix8gI iz5QqmsA2RS8VQq9QmnA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wruVp-00000005PM8-1zyJ; Thu, 06 Aug 2026 09:35:41 +0000 Received: from mail-pj2-x04.google.com ([2607:f8b0:4864:39::4]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wruVl-00000005PJN-334O for linux-riscv@lists.infradead.org; Thu, 06 Aug 2026 09:35:39 +0000 Received: by mail-pj2-x04.google.com with SMTP id d9443c01a7336-2cabf1f1051so6004155ad.0 for ; Thu, 06 Aug 2026 02:35:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1786008936; x=1786613736; darn=lists.infradead.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to:content-type; bh=iAi2qaVA1OaGq4fUWHi+grRNkf4AM4PgvPmY0Rr+XE4=; b=ko4UyEwUz7yldv/ewNdH9ueIvQGrtl8Rbl3zFr+1GEvU1c2RYD1hcaPu2MZhAY2OJm EcSc/HLvwkoXFQwJ1w3ZXbqOaAZtiZN6cO3Zz05STtoDyns6547j8bAR/uisQMkY/Gxl Y/pBmvlqqsO6kJFyNcpbS89VVtab/Y2JX8b6DSfSAhmdpgk5ihBjBWCFyuoGBl4PMnYs Y09Hw2QNRmX2xARi48FHVagVkKMy+KxAynKSgv6DvdAJjYsUbh5bmq1ja4fdd0EQG4f+ pCgVrVkBrUoQM8mkjV1Z2/qdi8z6mw/Q/uvzr8vx57q62iAWezHjQjUx+iXAu19UDiyz E8JQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1786008936; x=1786613736; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=iAi2qaVA1OaGq4fUWHi+grRNkf4AM4PgvPmY0Rr+XE4=; b=GJ4M9Xwy6eqXKTrbfieRNPIq8rJNkVVpf4TglUqFhTXDtZ0hI9QV+x/uKdAZlYdsKM DyUomlgqa3wrs0DdxtWSRfGpYsm1GP1+kC12M4qmANUINN2gUkUVzBvy7bFYIzMdozll PBa6CxmNSymnFDDznqB/28ql9wys5+qxrpeWcTsIMcoxq+wXq3F2RpgxDRtEmutabiDm 6xmzJBkAuL4CqG62puj9cDU2o398Ruv/voyArtsGm4Rh2wFL9iC1tOss0mgmxcK3G0Zh oTSkDzZ7C+kmr+s8Sl5Gguv1yntqaWYuTpRJaTp/0IOGVN1OmVN6M1ubO+JnZ7EcGgvV dmHg== X-Forwarded-Encrypted: i=1; AHgh+Rq+pWigBl8b1tOt39KvPJ/1rNSNniefz1pJ0RHW/5jURDGkMAMl3qX7TCBp31u3/F+F7CXinSi8MdpKlw==@lists.infradead.org X-Gm-Message-State: AOJu0YwB+k+jM6du6Txj3gLRqT8O1DUl/VFVo9Ii4gpgbksQpr2o1zwv D+YNe8JNsKOqw6FVQzb4Pca8cyb3XjPsekR+e4uTeDWCYbCYsNBC8boI X-Gm-Gg: AR+sD13EM1p+428NORQLpre6pPRna7EUWg/TVVor3A8J/brA3UU0jod1SvG4qFZNeQO raoBA75t2U3CwT7gkOSlv54xYk9dguEECjIi5dbjpAMeA/oeT1Gfg6LIr7nNmzonwpuci93Lyiv wQLmF/FE5oq+TaGWlomo0W84lYF0UXC1EFg0PJdKaJoqknmd+Ms1mWhsNhM9Mj98aBGf0RzWby7 JLxzRGS2KPza6y/CV14sVSVCZCba3U9NtHLKlFpkrq3ph0DL1DopL7NIf0MmYSZ018eDIrZZQbD jIRlNvNed/Gy2rqobjtBEZJwKPH9HiYrZB1RSa2GrZV8KJyzuckAg0OjRgqtB8A2wmFI4OIb3sA OIefn/wupG+b8iL3EFWAiDjbC4ef9d4NuBIUC0GnS6Knv0l+EGnh3goKoZBofbZDFpRf6L+cBQ/ zpmj6NwH4o71yr/E7RX6eqlgnv/tCTbZl5CUxMpt+Yx3gnZ4XS90PLlmtLQjIypBSnId9ZLNKeK w== X-Received: by 2002:a05:6a00:9515:b0:84c:1cd2:142e with SMTP id d2e1a72fcca58-84f4fe9e75cmr58122b3a.23.1786008936445; Thu, 06 Aug 2026 02:35:36 -0700 (PDT) Received: from intel.company.local ([210.184.73.204]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-84f453b0aeasm1043878b3a.13.2026.08.06.02.35.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 06 Aug 2026 02:35:35 -0700 (PDT) From: Wandun Chen To: catalin.marinas@arm.com, will@kernel.org, chenhuacai@kernel.org, pjw@kernel.org, palmer@dabbelt.com, aou@eecs.berkeley.edu, robh@kernel.org, saravanak@kernel.org, rppt@kernel.org, baoquan.he@linux.dev, pasha.tatashin@soleen.com, pratyush@kernel.org, m.szyprowski@samsung.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, linux-riscv@lists.infradead.org, devicetree@vger.kernel.org, linux-mm@kvack.org, kexec@lists.infradead.org, iommu@lists.linux.dev Cc: kernel@xen0n.name, alex@ghiti.fr, akpm@linux-foundation.org, ruirui.yang@linux.dev, robin.murphy@arm.com Subject: [PATCH v5 0/8] kdump: reduce vmcore size and capture time Date: Thu, 6 Aug 2026 17:35:11 +0800 Message-ID: <20260806093519.2907771-1-chenwandun1@gmail.com> X-Mailer: git-send-email 2.43.0 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260806_023537_767640_BB7350FD X-CRM114-Status: GOOD ( 12.03 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Wandun Chen On SoCs that carve out large firmware-owned reserved memory (GPU, camera ISP, ...), kdump currently dumps those carveouts as part of system RAM even though their contents are firmware state that is not useful for kernel crash analysis. This series introduces a 'dumpable' flag on struct reserved_mem and a MEMBLOCK_NODUMP flag in memblock to filter vmcore ELF header on DT-based architectures (arm64, riscv, loongarch). Reserved regions default to non-dumpable and are marked MEMBLOCK_NODUMP so kdump omits them; reusable CMA regions are explicitly marked dumpable in rmem_cma_setup() because their pages are handed back to the buddy allocator and may carry crash-relevant data. Since the reserved memory regions are filtered out, the vmcore is smaller in size and faster to produce. ACPI systems already filter reserved memory out of the vmcore through their existing path; only DT-based systems currently fail to filter these regions, which is what this series addresses. The flag lives in memblock itself rather than in a DT-only structure, so the mechanism is generic and both ACPI and DT systems can benefit from it (suggested by Rob, thanks). The series is based on linux-next and is organized as follows: Patches 1-2: Introduce MEMBLOCK_NODUMP in memblock and the dumpable flag on struct reserved_mem. Patches 3-4: Mark non-dumpable /reserved-memory and /memreserve/ entries with MEMBLOCK_NODUMP. Patch 5: Switch riscv to memblock so the NODUMP flag is visible to the vmcore ELF header builder; add (KEXEC_FILE && CRASH_DUMP) to riscv's ARCH_KEEP_MEMBLOCK condition. Patches 6-8: Fold the duplicated per-arch memblock walks into the weak defaults in crash_core, switch to for_each_mem_region(), and exclude MEMBLOCK_NODUMP regions from the vmcore ELF header. v4 --> v5: 1. Rework the mechanism around a memblock-level MEMBLOCK_NODUMP flag (suggested by Rob) instead of the v4 opt-in 'dumpable' flag on DT-only struct reserved_mem. 2. Switch the riscv vmcore elf header preparation to use memblock instead of the resource tree, aligning it with arm64 and loongarch, so riscv also can exclude reserved memory from vmcore. 3. Deduplicate the vmcore elf header preparation: arm64, riscv and loongarch open-coded the same logic, so fold it into shared __weak defaults in crash_core. 4. Drop the v4 patch that saved /memreserve/ entries into the reserved_mem array; /memreserve/ is now marked MEMBLOCK_NODUMP directly. v3 --> v4: 1. Rebase this series on v7.2-rc1. 2. Add two cleanup patches (patch 02/03). 3. Simplify patch 03 to avoid checking whether initial_boot_params is NULL multiple times, suggested by Rob. v2 --> v3: 1. Fix out-of-bounds issue if device tree lacks /reserved-memory node.[2] 2. Fix UAF issue when alloc_reserved_mem_array() fails. 3. Add some prepare patches. v1 --> v2: 1. v1 added an opt-out DT property ('linux,no-dump'). Per Rob's feedback [1], v2 drop that property and exclude reserve memory by default. 2. Split some prepared patches from the original patches. 3. Address coding-style comments on patch 5 from Rob. [1] https://lore.kernel.org/lkml/20260506144542.GA2072596-robh@kernel.org/ [2] https://sashiko.dev/#/patchset/20260520091844.592753-1-chenwandun%40lixiang.com?part=4 Wandun Chen (8): memblock: introduce MEMBLOCK_NODUMP flag of: reserved_mem: add dumpable flag to opt-in vmcore of: reserved_mem: mark /reserved-memory entries with MEMBLOCK_NODUMP of: reserved_mem: mark /memreserve/ entries as MEMBLOCK_NODUMP riscv: build crash_mem ranges from memblock instead of resource tree crash_core: fold duplicated memblock arch hooks into the weak default crash_core: replace for_each_mem_range() with for_each_mem_region() crash_core: skip MEMBLOCK_NODUMP regions when building vmcore ELF header arch/arm64/kernel/machine_kexec_file.c | 29 ------------------ arch/loongarch/kernel/machine_kexec_file.c | 27 ----------------- arch/riscv/Kconfig | 2 +- arch/riscv/kernel/machine_kexec_file.c | 33 -------------------- drivers/of/fdt.c | 2 ++ drivers/of/of_private.h | 1 + drivers/of/of_reserved_mem.c | 35 ++++++++++++++++++++++ include/linux/memblock.h | 9 ++++++ include/linux/of_reserved_mem.h | 1 + kernel/crash_core.c | 34 +++++++++++++++++++-- kernel/dma/contiguous.c | 1 + mm/memblock.c | 16 ++++++++++ 12 files changed, 98 insertions(+), 92 deletions(-) -- 2.43.0 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv