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Fri, 28 Nov 2025 09:33:14 -0800 (PST) Received: from localhost ([2a03:2880:10ff:4b::]) by smtp.gmail.com with ESMTPSA id 46e09a7af769-7c90fe0f65bsm1769459a34.24.2025.11.28.09.33.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 28 Nov 2025 09:33:13 -0800 (PST) From: Usama Arif To: rppt@kernel.org, Andrew Morton Cc: kas@kernel.org, changyuanl@google.com, graf@amazon.com, leitao@debian.org, thevlad@meta.com, pratyush@kernel.org, dave.hansen@linux.intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@meta.com, Usama Arif Subject: [PATCH v3 0/2] mm: only mark/clear KHO scratch memory when needed Date: Fri, 28 Nov 2025 17:29:32 +0000 Message-ID: <20251128173257.969322-1-usamaarif642@gmail.com> X-Mailer: git-send-email 2.47.3 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The scratch memory for kexec handover is used to bootstrap the kexec'ed kernel. Only the 1st 1MB is used as scratch, and its a hack to get around limitations with KHO. It is only needed when CONFIG_KEXEC_HANDOVER is enabled and only if it is a KHO boot (both checked by is_kho_boot). Add check to prevent marking a KHO scratch region unless needed. CONFIG_MEMBLOCK_KHO_SCRATCH is also removed as its only selected by KEXEC_HANDOVER. v2 -> v3: - is_kho_boot already has stubs when CONFIG_KEXEC_HANDOVER=n, no need to move the functions under CONFIG_KEXEC_HANDOVER (Pratyush Yadav) - Commit messsage improvements v1 -> v2: - Remove CONFIG_MEMBLOCK_KHO_SCRATCH (Kiryl Shutsemau) - Move memblock_mark/clear_kho_scratch under alread existing CONFIG_KEXEC_HANDOVER in memblock.c. Usama Arif (2): mm/memblock: remove CONFIG_MEMBLOCK_KHO_SCRATCH option mm/memblock: only mark/clear KHO scratch memory when needed include/linux/memblock.h | 2 +- kernel/Kconfig.kexec | 1 - mm/Kconfig | 4 ---- mm/memblock.c | 18 +++++++++++------- 4 files changed, 12 insertions(+), 13 deletions(-) -- 2.47.3