kernel/linux.git/arch/x86/boot, branch master

Merge tag 'x86_sev_for_v7.1_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2026-04-14T22:20:54+00:00

Pull x86 SEV updates from Borislav Petkov: - Change the SEV host code handling of when SNP gets enabled in order to allow the machine to claim SNP-related resources only when SNP guests are really going to be launched. The user requests this by loading the ccp module and thus it controls when SNP initialization is done So export an API which module code can call and do the necessary SNP setup only when really needed - Drop an unnecessary write-back and invalidate operation that was being performed too early, since the ccp driver already issues its own at the correct point in the initialization sequence - Drop the hotplug callbacks for enabling SNP on newly onlined CPUs, which were both architecturally unsound (the firmware rejects initialization if any CPU lacks the required configuration) and buggy (the MFDM SYSCFG MSR bit was not being set) - Code refactoring and cleanups to accomplish the above * tag 'x86_sev_for_v7.1_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: crypto/ccp: Update HV_FIXED page states to allow freeing of memory crypto/ccp: Implement SNP x86 shutdown x86/sev, crypto/ccp: Move HSAVE_PA setup to arch/x86/ x86/sev, crypto/ccp: Move SNP init to ccp driver x86/sev: Create snp_shutdown() x86/sev: Create snp_prepare() x86/sev: Create a function to clear/zero the RMP x86/sev: Rename SNP_FEATURES_PRESENT to SNP_FEATURES_IMPL x86/virt/sev: Keep the RMP table bookkeeping area mapped x86/virt/sev: Drop WBINVD before setting MSR_AMD64_SYSCFG_SNP_EN x86/virt/sev: Drop support for SNP hotplug

Merge tag 'kbuild-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux

2026-04-14T16:18:40+00:00

Pull Kbuild/Kconfig updates from Nicolas Schier: "Kbuild: - reject unexpected values for LLVM= - uapi: remove usage of toolchain headers - switch from '-fms-extensions' to '-fms-anonymous-structs' when available (currently: clang >= 23.0.0) - reduce the number of compiler-generated suffixes for clang thin-lto build - reduce output spam ("GEN Makefile") when building out of tree - improve portability for testing headers - also test UAPI headers against C++ compilers - drop build ID architecture allow-list in vdso_install - only run checksyscalls when necessary - update the debug information notes in reproducible-builds.rst - expand inlining hints with -fdiagnostics-show-inlining-chain Kconfig: - forbid multiple entries with the same symbol in a choice - error out on duplicated kconfig inclusion" * tag 'kbuild-7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (35 commits) kbuild: expand inlining hints with -fdiagnostics-show-inlining-chain kconfig: forbid multiple entries with the same symbol in a choice Documentation: kbuild: Update the debug information notes in reproducible-builds.rst checksyscalls: move instance functionality into generic code checksyscalls: only run when necessary checksyscalls: fail on all intermediate errors checksyscalls: move path to reference table to a variable kbuild: vdso_install: drop build ID architecture allow-list kbuild: vdso_install: gracefully handle images without build ID kbuild: vdso_install: hide readelf warnings kbuild: vdso_install: split out the readelf invocation kbuild: uapi: also test UAPI headers against C++ compilers kbuild: uapi: provide a C++ compatible dummy definition of NULL kbuild: uapi: handle UML in architecture-specific exclusion lists kbuild: uapi: move all include path flags together kbuild: uapi: move some compiler arguments out of the command definition check-uapi: use dummy libc includes check-uapi: honor ${CROSS_COMPILE} setting check-uapi: link into shared objects kbuild: reduce output spam when building out of tree ...

x86/sev: Rename SNP_FEATURES_PRESENT to SNP_FEATURES_IMPL

2026-03-16T20:08:50+00:00

Rename SNP_FEATURES_PRESENT to SNP_FEATURES_IMPL to denote its counterpart relationship with SNP_FEATURES_IMPL_REQ. [ bp: Drop stable@, massage commit message. ] Suggested-by: Borislav Petkov (AMD) Suggested-by: Tom Lendacky Signed-off-by: Kim Phillips Signed-off-by: Borislav Petkov (AMD) Link: https://patch.msgid.link/20260203222405.4065706-4-kim.phillips@amd.com

kbuild: Consolidate C dialect options

2026-03-12T11:52:37+00:00

Introduce CC_FLAGS_DIALECT to make it easier to update the various places in the tree that rely on the GNU C standard and Microsoft extensions flags atomically. All remaining uses of '-std=gnu11' and '-fms-extensions' are in the tools directory (which has its own build system) and other standalone Makefiles. This will allow the kernel to use a narrower option to enable the Microsoft anonymous tagged structure extension in a simpler manner. Place the CC_FLAGS_DIALECT block after the configuration include (so that a future change can move the selection of the flag to Kconfig) but before the arch/$(SRCARCH)/Makefile include (so that CC_FLAGS_DIALECT is available for use in those Makefiles). Signed-off-by: Nathan Chancellor Reviewed-by: Nicolas Schier Acked-by: Ard Biesheuvel Acked-by: Helge Deller # parisc Link: https://patch.msgid.link/20260223-fms-anonymous-structs-v1-1-8ee406d3c36c@kernel.org Signed-off-by: Nicolas Schier

Merge tag 'x86-urgent-2026-03-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2026-03-08T01:12:06+00:00

Pull x86 fixes from Ingo Molnar: - Fix SEV guest boot failures in certain circumstances, due to very early code relying on a BSS-zeroed variable that isn't actually zeroed yet an may contain non-zero bootup values Move the variable into the .data section go gain even earlier zeroing - Expose & allow the IBPB-on-Entry feature on SNP guests, which was not properly exposed to guests due to initial implementational caution - Fix O= build failure when CONFIG_EFI_SBAT_FILE is using relative file paths - Fix the various SNC (Sub-NUMA Clustering) topology enumeration bugs/artifacts (sched-domain build errors mostly). SNC enumeration data got more complicated with Granite Rapids X (GNR) and Clearwater Forest X (CWF), which exposed these bugs and made their effects more serious - Also use the now sane(r) SNC code to fix resctrl SNC detection bugs - Work around a historic libgcc unwinder bug in the vdso32 sigreturn code (again), which regressed during an overly aggressive recent cleanup of DWARF annotations * tag 'x86-urgent-2026-03-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/entry/vdso32: Work around libgcc unwinder bug x86/resctrl: Fix SNC detection x86/topo: Fix SNC topology mess x86/topo: Replace x86_has_numa_in_package x86/topo: Add topology_num_nodes_per_package() x86/numa: Store extra copy of numa_nodes_parsed x86/boot: Handle relative CONFIG_EFI_SBAT_FILE file paths x86/sev: Allow IBPB-on-Entry feature for SNP guests x86/boot/sev: Move SEV decompressor variables into the .data section

x86/boot: Handle relative CONFIG_EFI_SBAT_FILE file paths

2026-03-04T10:51:08+00:00

CONFIG_EFI_SBAT_FILE can be a relative path. When compiling using a different output directory (O=) the build currently fails because it can't find the filename set in CONFIG_EFI_SBAT_FILE: arch/x86/boot/compressed/sbat.S: Assembler messages: arch/x86/boot/compressed/sbat.S:6: Error: file not found: kernel.sbat Add $(srctree) as include dir for sbat.o. [ bp: Massage commit message. ] Fixes: 61b57d35396a ("x86/efi: Implement support for embedding SBAT data for x86") Signed-off-by: Jan Stancek Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Vitaly Kuznetsov Cc: Link: https://patch.msgid.link/f4eda155b0cef91d4d316b4e92f5771cb0aa7187.1772047658.git.jstancek@redhat.com

x86/sev: Allow IBPB-on-Entry feature for SNP guests

2026-03-02T10:08:59+00:00

The SEV-SNP IBPB-on-Entry feature does not require a guest-side implementation. It was added in Zen5 h/w, after the first SNP Zen implementation, and thus was not accounted for when the initial set of SNP features were added to the kernel. In its abundant precaution, commit 8c29f0165405 ("x86/sev: Add SEV-SNP guest feature negotiation support") included SEV_STATUS' IBPB-on-Entry bit as a reserved bit, thereby masking guests from using the feature. Allow guests to make use of IBPB-on-Entry when supported by the hypervisor, as the bit is now architecturally defined and safe to expose. Fixes: 8c29f0165405 ("x86/sev: Add SEV-SNP guest feature negotiation support") Signed-off-by: Kim Phillips Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Nikunj A Dadhania Reviewed-by: Tom Lendacky Cc: stable@kernel.org Link: https://patch.msgid.link/20260203222405.4065706-2-kim.phillips@amd.com

x86/boot/sev: Move SEV decompressor variables into the .data section

2026-03-02T10:08:33+00:00

As part of the work to remove the dependency on calling into the decompressor code (startup_64()) for a UEFI boot, a call to rmpadjust() was removed from sev_enable() in favor of checking the value of the snp_vmpl variable. When booting through a non-UEFI path and calling startup_64(), the call to sev_enable() is performed before the BSS section is zeroed. With the removal of the rmpadjust() call and the corresponding check of the return code, the snp_vmpl variable is checked. Since the kernel is running at VMPL0, the snp_vmpl variable will not have been set and should be the default value of 0. However, since the call occurs before the BSS is zeroed, the snp_vmpl variable may not actually be zero, which will cause the guest boot to fail. Since the decompressor relocates itself, the BSS would need to be cleared both before and after the relocation, but this would, in effect, cause all of the changes to BSS variables before relocation to be lost after relocation. Instead, move the snp_vmpl variable into the .data section so that it is initialized and the value made safe during relocation. As a pre-caution against future changes, move other SEV-related decompressor variables into the .data section, too. Fixes: 68a501d7fd82 ("x86/boot: Drop redundant RMPADJUST in SEV SVSM presence check") Signed-off-by: Tom Lendacky Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Ard Biesheuvel Reviewed-by: Changyuan Lyu Tested-by: Kevin Hui Tested-by: Changyuan Lyu Cc: stable@vger.kernel.org Link: https://patch.msgid.link/5648b7de5b0a5d0dfef3785f9582b718678c6448.1770217260.git.thomas.lendacky@amd.com

kbuild: Split .modinfo out from ELF_DETAILS

2026-02-26T18:50:19+00:00

Commit 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") added .modinfo to ELF_DETAILS while removing it from COMMON_DISCARDS, as it was needed in vmlinux.unstripped and ELF_DETAILS was present in all architecture specific vmlinux linker scripts. While this shuffle is fine for vmlinux, ELF_DETAILS and COMMON_DISCARDS may be used by other linker scripts, such as the s390 and x86 compressed boot images, which may not expect to have a .modinfo section. In certain circumstances, this could result in a bootloader failing to load the compressed kernel [1]. Commit ddc6cbef3ef1 ("s390/boot/vmlinux.lds.S: Ensure bzImage ends with SecureBoot trailer") recently addressed this for the s390 bzImage but the same bug remains for arm, parisc, and x86. The presence of .modinfo in the x86 bzImage was the root cause of the issue worked around with commit d50f21091358 ("kbuild: align modinfo section for Secureboot Authenticode EDK2 compat"). misc.c in arch/x86/boot/compressed includes lib/decompress_unzstd.c, which in turn includes lib/xxhash.c and its MODULE_LICENSE / MODULE_DESCRIPTION macros due to the STATIC definition. Split .modinfo out from ELF_DETAILS into its own macro and handle it in all vmlinux linker scripts. Discard .modinfo in the places where it was previously being discarded from being in COMMON_DISCARDS, as it has never been necessary in those uses. Cc: stable@vger.kernel.org Fixes: 3e86e4d74c04 ("kbuild: keep .modinfo section in vmlinux.unstripped") Reported-by: Ed W Closes: https://lore.kernel.org/587f25e0-a80e-46a5-9f01-87cb40cfa377@wildgooses.com/ [1] Tested-by: Ed W # x86_64 Link: https://patch.msgid.link/20260225-separate-modinfo-from-elf-details-v1-1-387ced6baf4b@kernel.org Signed-off-by: Nathan Chancellor

Merge tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-02-12T19:32:37+00:00

Pull MM updates from Andrew Morton: - "powerpc/64s: do not re-activate batched TLB flush" makes arch_{enter|leave}_lazy_mmu_mode() nest properly (Alexander Gordeev) It adds a generic enter/leave layer and switches architectures to use it. Various hacks were removed in the process. - "zram: introduce compressed data writeback" implements data compression for zram writeback (Richard Chang and Sergey Senozhatsky) - "mm: folio_zero_user: clear page ranges" adds clearing of contiguous page ranges for hugepages. Large improvements during demand faulting are demonstrated (David Hildenbrand) - "memcg cleanups" tidies up some memcg code (Chen Ridong) - "mm/damon: introduce {,max_}nr_snapshots and tracepoint for damos stats" improves DAMOS stat's provided information, deterministic control, and readability (SeongJae Park) - "selftests/mm: hugetlb cgroup charging: robustness fixes" fixes a few issues in the hugetlb cgroup charging selftests (Li Wang) - "Fix va_high_addr_switch.sh test failure - again" addresses several issues in the va_high_addr_switch test (Chunyu Hu) - "mm/damon/tests/core-kunit: extend existing test scenarios" improves the KUnit test coverage for DAMON (Shu Anzai) - "mm/khugepaged: fix dirty page handling for MADV_COLLAPSE" fixes a glitch in khugepaged which was causing madvise(MADV_COLLAPSE) to transiently return -EAGAIN (Shivank Garg) - "arch, mm: consolidate hugetlb early reservation" reworks and consolidates a pile of straggly code related to reservation of hugetlb memory from bootmem and creation of CMA areas for hugetlb (Mike Rapoport) - "mm: clean up anon_vma implementation" cleans up the anon_vma implementation in various ways (Lorenzo Stoakes) - "tweaks for __alloc_pages_slowpath()" does a little streamlining of the page allocator's slowpath code (Vlastimil Babka) - "memcg: separate private and public ID namespaces" cleans up the memcg ID code and prevents the internal-only private IDs from being exposed to userspace (Shakeel Butt) - "mm: hugetlb: allocate frozen gigantic folio" cleans up the allocation of frozen folios and avoids some atomic refcount operations (Kefeng Wang) - "mm/damon: advance DAMOS-based LRU sorting" improves DAMOS's movement of memory betewwn the active and inactive LRUs and adds auto-tuning of the ratio-based quotas and of monitoring intervals (SeongJae Park) - "Support page table check on PowerPC" makes CONFIG_PAGE_TABLE_CHECK_ENFORCED work on powerpc (Andrew Donnellan) - "nodemask: align nodes_and{,not} with underlying bitmap ops" makes nodes_and() and nodes_andnot() propagate the return values from the underlying bit operations, enabling some cleanup in calling code (Yury Norov) - "mm/damon: hide kdamond and kdamond_lock from API callers" cleans up some DAMON internal interfaces (SeongJae Park) - "mm/khugepaged: cleanups and scan limit fix" does some cleanup work in khupaged and fixes a scan limit accounting issue (Shivank Garg) - "mm: balloon infrastructure cleanups" goes to town on the balloon infrastructure and its page migration function. Mainly cleanups, also some locking simplification (David Hildenbrand) - "mm/vmscan: add tracepoint and reason for kswapd_failures reset" adds additional tracepoints to the page reclaim code (Jiayuan Chen) - "Replace wq users and add WQ_PERCPU to alloc_workqueue() users" is part of Marco's kernel-wide migration from the legacy workqueue APIs over to the preferred unbound workqueues (Marco Crivellari) - "Various mm kselftests improvements/fixes" provides various unrelated improvements/fixes for the mm kselftests (Kevin Brodsky) - "mm: accelerate gigantic folio allocation" greatly speeds up gigantic folio allocation, mainly by avoiding unnecessary work in pfn_range_valid_contig() (Kefeng Wang) - "selftests/damon: improve leak detection and wss estimation reliability" improves the reliability of two of the DAMON selftests (SeongJae Park) - "mm/damon: cleanup kdamond, damon_call(), damos filter and DAMON_MIN_REGION" does some cleanup work in the core DAMON code (SeongJae Park) - "Docs/mm/damon: update intro, modules, maintainer profile, and misc" performs maintenance work on the DAMON documentation (SeongJae Park) - "mm: add and use vma_assert_stabilised() helper" refactors and cleans up the core VMA code. The main aim here is to be able to use the mmap write lock's lockdep state to perform various assertions regarding the locking which the VMA code requires (Lorenzo Stoakes) - "mm, swap: swap table phase II: unify swapin use" removes some old swap code (swap cache bypassing and swap synchronization) which wasn't working very well. Various other cleanups and simplifications were made. The end result is a 20% speedup in one benchmark (Kairui Song) - "enable PT_RECLAIM on more 64-bit architectures" makes PT_RECLAIM available on 64-bit alpha, loongarch, mips, parisc, and um. Various cleanups were performed along the way (Qi Zheng) * tag 'mm-stable-2026-02-11-19-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (325 commits) mm/memory: handle non-split locks correctly in zap_empty_pte_table() mm: move pte table reclaim code to memory.c mm: make PT_RECLAIM depends on MMU_GATHER_RCU_TABLE_FREE mm: convert __HAVE_ARCH_TLB_REMOVE_TABLE to CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE config um: mm: enable MMU_GATHER_RCU_TABLE_FREE parisc: mm: enable MMU_GATHER_RCU_TABLE_FREE mips: mm: enable MMU_GATHER_RCU_TABLE_FREE LoongArch: mm: enable MMU_GATHER_RCU_TABLE_FREE alpha: mm: enable MMU_GATHER_RCU_TABLE_FREE mm: change mm/pt_reclaim.c to use asm/tlb.h instead of asm-generic/tlb.h mm/damon/stat: remove __read_mostly from memory_idle_ms_percentiles zsmalloc: make common caches global mm: add SPDX id lines to some mm source files mm/zswap: use %pe to print error pointers mm/vmscan: use %pe to print error pointers mm/readahead: fix typo in comment mm: khugepaged: fix NR_FILE_PAGES and NR_SHMEM in collapse_file() mm: refactor vma_map_pages to use vm_insert_pages mm/damon: unify address range representation with damon_addr_range mm/cma: replace snprintf with strscpy in cma_new_area ...