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31 hoursMerge tag 'mm-stable-2025-07-30-15-25' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "As usual, many cleanups. The below blurbiage describes 42 patchsets. 21 of those are partially or fully cleanup work. "cleans up", "cleanup", "maintainability", "rationalizes", etc. I never knew the MM code was so dirty. "mm: ksm: prevent KSM from breaking merging of new VMAs" (Lorenzo Stoakes) addresses an issue with KSM's PR_SET_MEMORY_MERGE mode: newly mapped VMAs were not eligible for merging with existing adjacent VMAs. "mm/damon: introduce DAMON_STAT for simple and practical access monitoring" (SeongJae Park) adds a new kernel module which simplifies the setup and usage of DAMON in production environments. "stop passing a writeback_control to swap/shmem writeout" (Christoph Hellwig) is a cleanup to the writeback code which removes a couple of pointers from struct writeback_control. "drivers/base/node.c: optimization and cleanups" (Donet Tom) contains largely uncorrelated cleanups to the NUMA node setup and management code. "mm: userfaultfd: assorted fixes and cleanups" (Tal Zussman) does some maintenance work on the userfaultfd code. "Readahead tweaks for larger folios" (Ryan Roberts) implements some tuneups for pagecache readahead when it is reading into order>0 folios. "selftests/mm: Tweaks to the cow test" (Mark Brown) provides some cleanups and consistency improvements to the selftests code. "Optimize mremap() for large folios" (Dev Jain) does that. A 37% reduction in execution time was measured in a memset+mremap+munmap microbenchmark. "Remove zero_user()" (Matthew Wilcox) expunges zero_user() in favor of the more modern memzero_page(). "mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes" (David Hildenbrand) addresses some warts which David noticed in the huge page code. These were not known to be causing any issues at this time. "mm/damon: use alloc_migrate_target() for DAMOS_MIGRATE_{HOT,COLD" (SeongJae Park) provides some cleanup and consolidation work in DAMON. "use vm_flags_t consistently" (Lorenzo Stoakes) uses vm_flags_t in places where we were inappropriately using other types. "mm/memfd: Reserve hugetlb folios before allocation" (Vivek Kasireddy) increases the reliability of large page allocation in the memfd code. "mm: Remove pXX_devmap page table bit and pfn_t type" (Alistair Popple) removes several now-unneeded PFN_* flags. "mm/damon: decouple sysfs from core" (SeongJae Park) implememnts some cleanup and maintainability work in the DAMON sysfs layer. "madvise cleanup" (Lorenzo Stoakes) does quite a lot of cleanup/maintenance work in the madvise() code. "madvise anon_name cleanups" (Vlastimil Babka) provides additional cleanups on top or Lorenzo's effort. "Implement numa node notifier" (Oscar Salvador) creates a standalone notifier for NUMA node memory state changes. Previously these were lumped under the more general memory on/offline notifier. "Make MIGRATE_ISOLATE a standalone bit" (Zi Yan) cleans up the pageblock isolation code and fixes a potential issue which doesn't seem to cause any problems in practice. "selftests/damon: add python and drgn based DAMON sysfs functionality tests" (SeongJae Park) adds additional drgn- and python-based DAMON selftests which are more comprehensive than the existing selftest suite. "Misc rework on hugetlb faulting path" (Oscar Salvador) fixes a rather obscure deadlock in the hugetlb fault code and follows that fix with a series of cleanups. "cma: factor out allocation logic from __cma_declare_contiguous_nid" (Mike Rapoport) rationalizes and cleans up the highmem-specific code in the CMA allocator. "mm/migration: rework movable_ops page migration (part 1)" (David Hildenbrand) provides cleanups and future-preparedness to the migration code. "mm/damon: add trace events for auto-tuned monitoring intervals and DAMOS quota" (SeongJae Park) adds some tracepoints to some DAMON auto-tuning code. "mm/damon: fix misc bugs in DAMON modules" (SeongJae Park) does that. "mm/damon: misc cleanups" (SeongJae Park) also does what it claims. "mm: folio_pte_batch() improvements" (David Hildenbrand) cleans up the large folio PTE batching code. "mm/damon/vaddr: Allow interleaving in migrate_{hot,cold} actions" (SeongJae Park) facilitates dynamic alteration of DAMON's inter-node allocation policy. "Remove unmap_and_put_page()" (Vishal Moola) provides a couple of page->folio conversions. "mm: per-node proactive reclaim" (Davidlohr Bueso) implements a per-node control of proactive reclaim - beyond the current memcg-based implementation. "mm/damon: remove damon_callback" (SeongJae Park) replaces the damon_callback interface with a more general and powerful damon_call()+damos_walk() interface. "mm/mremap: permit mremap() move of multiple VMAs" (Lorenzo Stoakes) implements a number of mremap cleanups (of course) in preparation for adding new mremap() functionality: newly permit the remapping of multiple VMAs when the user is specifying MREMAP_FIXED. It still excludes some specialized situations where this cannot be performed reliably. "drop hugetlb_free_pgd_range()" (Anthony Yznaga) switches some sparc hugetlb code over to the generic version and removes the thus-unneeded hugetlb_free_pgd_range(). "mm/damon/sysfs: support periodic and automated stats update" (SeongJae Park) augments the present userspace-requested update of DAMON sysfs monitoring files. Automatic update is now provided, along with a tunable to control the update interval. "Some randome fixes and cleanups to swapfile" (Kemeng Shi) does what is claims. "mm: introduce snapshot_page" (Luiz Capitulino and David Hildenbrand) provides (and uses) a means by which debug-style functions can grab a copy of a pageframe and inspect it locklessly without tripping over the races inherent in operating on the live pageframe directly. "use per-vma locks for /proc/pid/maps reads" (Suren Baghdasaryan) addresses the large contention issues which can be triggered by reads from that procfs file. Latencies are reduced by more than half in some situations. The series also introduces several new selftests for the /proc/pid/maps interface. "__folio_split() clean up" (Zi Yan) cleans up __folio_split()! "Optimize mprotect() for large folios" (Dev Jain) provides some quite large (>3x) speedups to mprotect() when dealing with large folios. "selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup" (wang lian) does some cleanup work in the selftests code. "tools/testing: expand mremap testing" (Lorenzo Stoakes) extends the mremap() selftest in several ways, including adding more checking of Lorenzo's recently added "permit mremap() move of multiple VMAs" feature. "selftests/damon/sysfs.py: test all parameters" (SeongJae Park) extends the DAMON sysfs interface selftest so that it tests all possible user-requested parameters. Rather than the present minimal subset" * tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (370 commits) MAINTAINERS: add missing headers to mempory policy & migration section MAINTAINERS: add missing file to cgroup section MAINTAINERS: add MM MISC section, add missing files to MISC and CORE MAINTAINERS: add missing zsmalloc file MAINTAINERS: add missing files to page alloc section MAINTAINERS: add missing shrinker files MAINTAINERS: move memremap.[ch] to hotplug section MAINTAINERS: add missing mm_slot.h file THP section MAINTAINERS: add missing interval_tree.c to memory mapping section MAINTAINERS: add missing percpu-internal.h file to per-cpu section mm/page_alloc: remove trace_mm_alloc_contig_migrate_range_info() selftests/damon: introduce _common.sh to host shared function selftests/damon/sysfs.py: test runtime reduction of DAMON parameters selftests/damon/sysfs.py: test non-default parameters runtime commit selftests/damon/sysfs.py: generalize DAMON context commit assertion selftests/damon/sysfs.py: generalize monitoring attributes commit assertion selftests/damon/sysfs.py: generalize DAMOS schemes commit assertion selftests/damon/sysfs.py: test DAMOS filters commitment selftests/damon/sysfs.py: generalize DAMOS scheme commit assertion selftests/damon/sysfs.py: test DAMOS destinations commitment ...
4 daysMerge tag 'hardening-v6.17-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull hardening updates from Kees Cook: - Introduce and start using TRAILING_OVERLAP() helper for fixing embedded flex array instances (Gustavo A. R. Silva) - mux: Convert mux_control_ops to a flex array member in mux_chip (Thorsten Blum) - string: Group str_has_prefix() and strstarts() (Andy Shevchenko) - Remove KCOV instrumentation from __init and __head (Ritesh Harjani, Kees Cook) - Refactor and rename stackleak feature to support Clang - Add KUnit test for seq_buf API - Fix KUnit fortify test under LTO * tag 'hardening-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (22 commits) sched/task_stack: Add missing const qualifier to end_of_stack() kstack_erase: Support Clang stack depth tracking kstack_erase: Add -mgeneral-regs-only to silence Clang warnings init.h: Disable sanitizer coverage for __init and __head kstack_erase: Disable kstack_erase for all of arm compressed boot code x86: Handle KCOV __init vs inline mismatches arm64: Handle KCOV __init vs inline mismatches s390: Handle KCOV __init vs inline mismatches arm: Handle KCOV __init vs inline mismatches mips: Handle KCOV __init vs inline mismatch powerpc/mm/book3s64: Move kfence and debug_pagealloc related calls to __init section configs/hardening: Enable CONFIG_INIT_ON_FREE_DEFAULT_ON configs/hardening: Enable CONFIG_KSTACK_ERASE stackleak: Split KSTACK_ERASE_CFLAGS from GCC_PLUGINS_CFLAGS stackleak: Rename stackleak_track_stack to __sanitizer_cov_stack_depth stackleak: Rename STACKLEAK to KSTACK_ERASE seq_buf: Introduce KUnit tests string: Group str_has_prefix() and strstarts() kunit/fortify: Add back "volatile" for sizeof() constants acpi: nfit: intel: avoid multiple -Wflex-array-member-not-at-end warnings ...
8 daysx86: Handle KCOV __init vs inline mismatchesKees Cook
GCC appears to have kind of fragile inlining heuristics, in the sense that it can change whether or not it inlines something based on optimizations. It looks like the kcov instrumentation being added (or in this case, removed) from a function changes the optimization results, and some functions marked "inline" are _not_ inlined. In that case, we end up with __init code calling a function not marked __init, and we get the build warnings I'm trying to eliminate in the coming patch that adds __no_sanitize_coverage to __init functions: WARNING: modpost: vmlinux: section mismatch in reference: xbc_exit+0x8 (section: .text.unlikely) -> _xbc_exit (section: .init.text) WARNING: modpost: vmlinux: section mismatch in reference: real_mode_size_needed+0x15 (section: .text.unlikely) -> real_mode_blob_end (section: .init.data) WARNING: modpost: vmlinux: section mismatch in reference: __set_percpu_decrypted+0x16 (section: .text.unlikely) -> early_set_memory_decrypted (section: .init.text) WARNING: modpost: vmlinux: section mismatch in reference: memblock_alloc_from+0x26 (section: .text.unlikely) -> memblock_alloc_try_nid (section: .init.text) WARNING: modpost: vmlinux: section mismatch in reference: acpi_arch_set_root_pointer+0xc (section: .text.unlikely) -> x86_init (section: .init.data) WARNING: modpost: vmlinux: section mismatch in reference: acpi_arch_get_root_pointer+0x8 (section: .text.unlikely) -> x86_init (section: .init.data) WARNING: modpost: vmlinux: section mismatch in reference: efi_config_table_is_usable+0x16 (section: .text.unlikely) -> xen_efi_config_table_is_usable (section: .init.text) This problem is somewhat fragile (though using either __always_inline or __init will deterministically solve it), but we've tripped over this before with GCC and the solution has usually been to just use __always_inline and move on. For x86 this means forcing several functions to be inline with __always_inline. Link: https://lore.kernel.org/r/20250724055029.3623499-2-kees@kernel.org Signed-off-by: Kees Cook <kees@kernel.org>
2025-07-13mm/page_alloc: add support for initializing pageblock as isolatedZi Yan
MIGRATE_ISOLATE is a standalone bit, so a pageblock cannot be initialized to just MIGRATE_ISOLATE. Add init_pageblock_migratetype() to enable initialize a pageblock with a migratetype and isolated. Link: https://lkml.kernel.org/r/20250617021115.2331563-4-ziy@nvidia.com Signed-off-by: Zi Yan <ziy@nvidia.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Hildenbrand <david@redhat.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Brendan Jackman <jackmanb@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kirill A. Shuemov <kirill.shutemov@linux.intel.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Richard Chang <richardycc@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-06-19kho: initialize tail pages for higher order folios properlyPratyush Yadav
Currently, when restoring higher order folios, kho_restore_folio() only calls prep_compound_page() on all the pages. That is not enough to properly initialize the folios. The managed page count does not get updated, the reserved flag does not get dropped, and page count does not get initialized properly. Restoring a higher order folio with it results in the following BUG with CONFIG_DEBUG_VM when attempting to free the folio: BUG: Bad page state in process test pfn:104e2b page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffffffffffffffff pfn:0x104e2b flags: 0x2fffff80000000(node=0|zone=2|lastcpupid=0x1fffff) raw: 002fffff80000000 0000000000000000 00000000ffffffff 0000000000000000 raw: ffffffffffffffff 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: nonzero _refcount [...] Call Trace: <TASK> dump_stack_lvl+0x4b/0x70 bad_page.cold+0x97/0xb2 __free_frozen_pages+0x616/0x850 [...] Combine the path for 0-order and higher order folios, initialize the tail pages with a count of zero, and call adjust_managed_page_count() to account for all the pages instead of just missing them. In addition, since all the KHO-preserved pages get marked with MEMBLOCK_RSRV_NOINIT by deserialize_bitmap(), the reserved flag is not actually set (as can also be seen from the flags of the dumped page in the logs above). So drop the ClearPageReserved() calls. [ptyadav@amazon.de: declare i in the loop instead of at the top] Link: https://lkml.kernel.org/r/20250613125916.39272-1-pratyush@kernel.org Link: https://lkml.kernel.org/r/20250605171143.76963-1-pratyush@kernel.org Fixes: fc33e4b44b27 ("kexec: enable KHO support for memory preservation") Signed-off-by: Pratyush Yadav <ptyadav@amazon.de> Reviewed-by: Pasha Tatashin <pasha.tatashin@soleen.com> Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Cc: Alexander Graf <graf@amazon.com> Cc: Baoquan He <bhe@redhat.com> Cc: Changyuan Lyu <changyuanl@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12kexec: add KHO support to kexec file loadsAlexander Graf
Kexec has 2 modes: A user space driven mode and a kernel driven mode. For the kernel driven mode, kernel code determines the physical addresses of all target buffers that the payload gets copied into. With KHO, we can only safely copy payloads into the "scratch area". Teach the kexec file loader about it, so it only allocates for that area. In addition, enlighten it with support to ask the KHO subsystem for its respective payloads to copy into target memory. Also teach the KHO subsystem how to fill the images for file loads. Link: https://lkml.kernel.org/r/20250509074635.3187114-8-changyuanl@google.com Signed-off-by: Alexander Graf <graf@amazon.com> Co-developed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Co-developed-by: Changyuan Lyu <changyuanl@google.com> Signed-off-by: Changyuan Lyu <changyuanl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Anthony Yznaga <anthony.yznaga@oracle.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ashish Kalra <ashish.kalra@amd.com> Cc: Ben Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Betkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Gowans <jgowans@amazon.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pratyush Yadav <ptyadav@amazon.de> Cc: Rob Herring <robh@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Lendacky <thomas.lendacky@amd.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12kexec: enable KHO support for memory preservationMike Rapoport (Microsoft)
Introduce APIs allowing KHO users to preserve memory across kexec and get access to that memory after boot of the kexeced kernel kho_preserve_folio() - record a folio to be preserved over kexec kho_restore_folio() - recreates the folio from the preserved memory kho_preserve_phys() - record physically contiguous range to be preserved over kexec. The memory preservations are tracked by two levels of xarrays to manage chunks of per-order 512 byte bitmaps. For instance if PAGE_SIZE = 4096, the entire 1G order of a 1TB x86 system would fit inside a single 512 byte bitmap. For order 0 allocations each bitmap will cover 16M of address space. Thus, for 16G of memory at most 512K of bitmap memory will be needed for order 0. At serialization time all bitmaps are recorded in a linked list of pages for the next kernel to process and the physical address of the list is recorded in KHO FDT. The next kernel then processes that list, reserves the memory ranges and later, when a user requests a folio or a physical range, KHO restores corresponding memory map entries. Link: https://lkml.kernel.org/r/20250509074635.3187114-7-changyuanl@google.com Suggested-by: Jason Gunthorpe <jgg@nvidia.com> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Co-developed-by: Changyuan Lyu <changyuanl@google.com> Signed-off-by: Changyuan Lyu <changyuanl@google.com> Cc: Alexander Graf <graf@amazon.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Anthony Yznaga <anthony.yznaga@oracle.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ashish Kalra <ashish.kalra@amd.com> Cc: Ben Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Betkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Gowans <jgowans@amazon.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pratyush Yadav <ptyadav@amazon.de> Cc: Rob Herring <robh@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Lendacky <thomas.lendacky@amd.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12kexec: add KHO parsing supportAlexander Graf
When we have a KHO kexec, we get an FDT blob and scratch region to populate the state of the system. Provide helper functions that allow architecture code to easily handle memory reservations based on them and give device drivers visibility into the KHO FDT and memory reservations so they can recover their own state. Include a fix from Arnd Bergmann <arnd@arndb.de> https://lore.kernel.org/lkml/20250424093302.3894961-1-arnd@kernel.org/. Link: https://lkml.kernel.org/r/20250509074635.3187114-6-changyuanl@google.com Signed-off-by: Alexander Graf <graf@amazon.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Co-developed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Co-developed-by: Changyuan Lyu <changyuanl@google.com> Signed-off-by: Changyuan Lyu <changyuanl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Anthony Yznaga <anthony.yznaga@oracle.com> Cc: Ashish Kalra <ashish.kalra@amd.com> Cc: Ben Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Betkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Gowans <jgowans@amazon.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Pratyush Yadav <ptyadav@amazon.de> Cc: Rob Herring <robh@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Lendacky <thomas.lendacky@amd.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12kexec: add Kexec HandOver (KHO) generation helpersAlexander Graf
Add the infrastructure to generate Kexec HandOver metadata. Kexec HandOver is a mechanism that allows Linux to preserve state - arbitrary properties as well as memory locations - across kexec. It does so using 2 concepts: 1) KHO FDT - Every KHO kexec carries a KHO specific flattened device tree blob that describes preserved memory regions. Device drivers can register to KHO to serialize and preserve their states before kexec. 2) Scratch Regions - CMA regions that we allocate in the first kernel. CMA gives us the guarantee that no handover pages land in those regions, because handover pages must be at a static physical memory location. We use these regions as the place to load future kexec images so that they won't collide with any handover data. Link: https://lkml.kernel.org/r/20250509074635.3187114-5-changyuanl@google.com Signed-off-by: Alexander Graf <graf@amazon.com> Co-developed-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Signed-off-by: Mike Rapoport (Microsoft) <rppt@kernel.org> Co-developed-by: Pratyush Yadav <ptyadav@amazon.de> Signed-off-by: Pratyush Yadav <ptyadav@amazon.de> Co-developed-by: Changyuan Lyu <changyuanl@google.com> Signed-off-by: Changyuan Lyu <changyuanl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Anthony Yznaga <anthony.yznaga@oracle.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Ashish Kalra <ashish.kalra@amd.com> Cc: Ben Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Betkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Gowans <jgowans@amazon.com> Cc: Jason Gunthorpe <jgg@nvidia.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Krzysztof Kozlowski <krzk@kernel.org> Cc: Marc Rutland <mark.rutland@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rob Herring <robh@kernel.org> Cc: Saravana Kannan <saravanak@google.com> Cc: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleinxer <tglx@linutronix.de> Cc: Thomas Lendacky <thomas.lendacky@amd.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>