The patch titled Subject: kho: mm: don't allow deferred struct page with KHO has been added to the -mm mm-hotfixes-unstable branch. Its filename is kho-mm-dont-allow-deferred-struct-page-with-kho.patch
This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...
This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------ From: Pasha Tatashin pasha.tatashin@soleen.com Subject: kho: mm: don't allow deferred struct page with KHO Date: Fri, 8 Aug 2025 20:18:03 +0000
KHO uses struct pages for the preserved memory early in boot, however, with deferred struct page initialization, only a small portion of memory has properly initialized struct pages.
This problem was detected where vmemmap is poisoned, and illegal flag combinations are detected.
Don't allow them to be enabled together, and later we will have to teach KHO to work properly with deferred struct page init kernel feature.
Link: https://lkml.kernel.org/r/20250808201804.772010-3-pasha.tatashin@soleen.com Fixes: 990a950fe8fd ("kexec: add config option for KHO") Signed-off-by: Pasha Tatashin pasha.tatashin@soleen.com Acked-by: Mike Rapoport (Microsoft) rppt@kernel.org Acked-by: Pratyush Yadav pratyush@kernel.org Cc: Alexander Graf graf@amazon.com Cc: Arnd Bergmann arnd@arndb.de Cc: Baoquan He bhe@redhat.com Cc: Changyuan Lyu changyuanl@google.com Cc: Coiby Xu coxu@redhat.com Cc: Dave Vasilevsky dave@vasilevsky.ca Cc: Eric Biggers ebiggers@google.com Cc: Kees Cook kees@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---
kernel/Kconfig.kexec | 1 + 1 file changed, 1 insertion(+)
--- a/kernel/Kconfig.kexec~kho-mm-dont-allow-deferred-struct-page-with-kho +++ a/kernel/Kconfig.kexec @@ -97,6 +97,7 @@ config KEXEC_JUMP config KEXEC_HANDOVER bool "kexec handover" depends on ARCH_SUPPORTS_KEXEC_HANDOVER && ARCH_SUPPORTS_KEXEC_FILE + depends on !DEFERRED_STRUCT_PAGE_INIT select MEMBLOCK_KHO_SCRATCH select KEXEC_FILE select DEBUG_FS _
Patches currently in -mm which might be from pasha.tatashin@soleen.com are
kho-init-new_physxa-phys_bits-to-fix-lockdep.patch kho-mm-dont-allow-deferred-struct-page-with-kho.patch kho-warn-if-kho-is-disabled-due-to-an-error.patch