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charset=us-ascii Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260918_083107_948265_4183E6C0 X-CRM114-Status: GOOD ( 32.15 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On 09/18/26 at 10:03am, Mike Rapoport wrote: > Hi, > > On Tue, Sep 15, 2026 at 09:01:07PM +0800, Wandun wrote: > > On 9/2/26 15:31, Wandun Chen wrote: > > > From: Wandun Chen ...snip... > > > 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) [1]. > > > > > > Since the reserved memory regions are filtered out, the vmcore is > > > smaller in size and faster to produce. > > > > > > The series is based on linux-next and is organized as follows: > > > > > > Patches 1-4: Preparation and bugfixes: fix the missing HugeTLB > > > flagname, switch riscv crash_mem to memblock, fold the > > > duplicated per-arch memblock walks into the weak > > > defaults, and serialize crash header preparation against > > > memory hotplug. > > > Patches 5-9: NODUMP infrastructure: switch crash_core to > > > for_each_mem_region(), introduce the MEMBLOCK_NODUMP > > > flag, add a dumpable flag to struct reserved_mem, and > > > mark /reserved-memory and /memreserve/ entries with > > > MEMBLOCK_NODUMP flag. > > > Patch 10: Exclude MEMBLOCK_NODUMP regions from the vmcore ELF > > > header. > > > > Hi, > > > > Gentle ping on the remaining patches of this series. > > Patches 1, 7, 8 and 9 have been reviewed (thanks Mike and Marek); > > Still looking for review on patches 2-6 and 10. > > I'm waiting for reviews from Baoquan and Dave for crash core patches before > applying this series. I will go through the crash core patches, thanks for reminding. > > > Would appreciate a look when you have a moment, happy to rework > > anything based on feedback. > > > > Best regards, > > Wanun > > > > > > > > In v5, Sashiko found some pre-existing issues related to reserved-memory, > > > and has no dependency on this series, so these issues have been addressed > > > in a separate series [2]. > > > > > > v5 --> v6: > > > 1. Serialize crash header preparation against memory hotplug to avoid > > > out-of-bounds or use-after-free issues. > > > > > > 2. MEMBLOCK_NODUMP marking is now done after memblock allows resizing, > > > avoiding a panic from too few regions before resize is permitted. > > > > > > 3. Reordered the patches, put pre-existing bugfixes earlier in the series. > > > > > > > > > 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. 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 [3], 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/20260723234126.GA3253409-robh@kernel.org/ > > > [2] https://lore.kernel.org/lkml/20260818092420.2859026-1-chenwandun1@gmail.com/ > > > [3] https://lore.kernel.org/lkml/20260506144542.GA2072596-robh@kernel.org/ > > > > > > Meijing Zhao (1): > > > mm: memblock: add missing HugeTLB flag name > > > > > > Wandun Chen (9): > > > riscv: build crash_mem ranges from memblock instead of resource tree > > > crash_core: fold duplicated memblock arch hooks into the weak default > > > crash_core: serialize crash header preparation against hotplug > > > crash_core: replace for_each_mem_range() with for_each_mem_region() > > > 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 > > > 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 -------------- > > > arch/x86/kernel/crash.c | 2 +- > > > drivers/of/fdt.c | 2 + > > > drivers/of/of_private.h | 2 + > > > drivers/of/of_reserved_mem.c | 48 ++++++++++++++++++++ > > > include/linux/crash_core.h | 2 + > > > include/linux/memblock.h | 9 ++++ > > > include/linux/of_reserved_mem.h | 1 + > > > kernel/crash_core.c | 51 ++++++++++++++++++++-- > > > kernel/dma/contiguous.c | 1 + > > > mm/memblock.c | 17 ++++++++ > > > 14 files changed, 131 insertions(+), 95 deletions(-) > > > > > > > > > -- > Sincerely yours, > Mike.