kernel/linux.git/arch/x86/Makefile, branch v7.2-rc5

Merge tag 'x86-cpu-2026-06-14' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip

2026-06-15T09:55:17+00:00

Pull x86 cpuid updates from Ingo Molnar: - CPUID API updates (Ahmed S. Darwish): - Introduce a centralized CPUID parser - Introduce a centralized CPUID data model - Introduce - Rename cpuid_leaf()/cpuid_subleaf() APIs - treewide: Explicitly include the x86 CPUID headers - Update to x86-cpuid-db v3.1 (Maciej Wieczor-Retman) - Continued removal of pre-i586 support and related simplifications (Ingo Molnar) - Add Intel CPU model number for rugged Panther Lake (Tony Luck) - Misc fixes, updates and cleanups by Arnd Bergmann, Chao Gao, Lukas Bulwahn, Sohil Mehta, Maciej Wieczor-Retman. * tag 'x86-cpu-2026-06-14' of gitolite.kernel.org:pub/scm/linux/kernel/git/tip/tip: (25 commits) x86/cpu: Make CONFIG_X86_CX8 unconditional x86/cpu: Remove unused !CONFIG_X86_TSC code x86/cpuid: Update bitfields to x86-cpuid-db v3.1 tools/x86/kcpuid: Update bitfields to x86-cpuid-db v3.1 x86/cpu: Make CONFIG_X86_TSC unconditional MAINTAINERS: Drop obsolete FPU EMULATOR section x86/cpu: Fix a F00F bug warning and clean up surrounding code x86/cpu: Add Intel CPU model number for rugged Panther Lake x86/cpuid: Introduce a centralized CPUID parser x86/cpu: Introduce a centralized CPUID data model x86/cpuid: Introduce x86/cpuid: Rename cpuid_leaf()/cpuid_subleaf() APIs x86/cpu: Do not include the CPUID API header in asm/processor.h Documentation: core-api/cpu_hotplug: Remove stale cpu0_hotplug docs x86/cpu, cpufreq: Remove AMD ELAN support x86/fpu: Remove the math-emu/ FPU emulation library x86/fpu: Remove the 'no387' boot option x86/fpu: Remove MATH_EMULATION and related glue code treewide: Explicitly include the x86 CPUID headers x86/cpu: Remove the CONFIG_X86_INVD_BUG quirk ...

Merge tag 'kbuild-7.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux

2026-06-14T23:31:15+00:00

Pull Kbuild / Kconfig updates from Nathan Chancellor: "Kbuild: - Remove broken module linking exclusion for BTF - Add documentation around how offset header files work - Include unstripped vDSO libraries in pacman packages - Bump minimum version of LLVM for building the kernel to 17.0.1 and clean up unnecessary workarounds - Use a context manager in run-clang-tools - Add dist macro value if present to release tag for RPM packages - Detect and report truncated buf_printf() output in modpost - Add __llvm_covfun and __llvm_covmap to section whitelist in modpost - Support Clang's distributed ThinLTO mode - Remove architecture specific configurations for AutoFDO and Propeller to ease individual architecture maintenance Kconfig: - Add kconfig-sym-check target to look for dangling Kconfig symbol references and invalid tristate literal values - Harden against potential NULL pointer dereference - Fix typo in Kconfig test comment" * tag 'kbuild-7.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (31 commits) kconfig: tests: fix typo in comment kconfig: Remove the architecture specific config for Propeller kconfig: Remove the architecture specific config for AutoFDO modpost: Add __llvm_covfun and __llvm_covmap to section_white_list kconfig: add kconfig-sym-check static checker kbuild: Remove unnecessary 'T' modifier in cmd_ar_builtin_fixup kbuild: distributed build support for Clang ThinLTO kbuild: move vmlinux.a build rule to scripts/Makefile.vmlinux_a scripts: modpost: detect and report truncated buf_printf() output kbuild: rpm-pkg: append %{?dist} macro to Release tag run-clang-tools: run multiprocessing.Pool as context manager compiler-clang.h: Drop explicit version number from "all" diagnostic macro compiler-clang.h: Remove __cleanup -Wunused-variable workaround kbuild: Remove check for broken scoping with clang < 17 in CC_HAS_ASM_GOTO_OUTPUT x86/entry/vdso32: Remove conditional omission of '.cfi_offset eflags' x86/module: Revert "Deal with GOT based stack cookie load on Clang < 17" x86/build: Drop unnecessary '-ffreestanding' addition to KBUILD_CFLAGS scripts/Makefile.warn: Drop -Wformat handling for clang < 16 riscv: Drop tautological condition from TOOLCHAIN_NEEDS_OLD_ISA_SPEC riscv: Remove tautological condition from selection of ARCH_SUPPORTS_CFI ...

x86/build: Drop unnecessary '-ffreestanding' addition to KBUILD_CFLAGS

2026-05-27T22:20:05+00:00

Now that the minimum supported version of LLVM for building the kernel has been raised to 17.0.1, the addition of '-ffreestanding' to KBUILD_CFLAGS for 32-bit x86 is unnecessary, as the linked LLVM bug is resolved in all supported LLVM versions. 16cb16e0d285 ("x86/build: Remove -ffreestanding on i386 with GCC") intended to make the addition of '-ffreestanding' clang only but due to a bug in the adjusted check from d70da12453ac ("hardening: Enable i386 FORTIFY_SOURCE on Clang 16+") it has been applied for all versions of GCC and clang < 16.0.0. There are no known problems with removing this for GCC but if one surfaces, it can be restored under a CONFIG_CC_IS_GCC block. Link: https://patch.msgid.link/20260517-bump-minimum-supported-llvm-version-to-17-v2-11-b3b8cda46bdd@kernel.org Signed-off-by: Nathan Chancellor

rust: kasan/kbuild: fix rustc-option when cross-compiling

2026-05-26T07:44:54+00:00

The Makefile version of rustc-option currently checks whether the option exists for the host target instead of the target actually being compiled for. It was done this way in commit 46e24a545cdb ("rust: kasan/kbuild: fix missing flags on first build") to avoid a circular dependency on target.json. However, because of this, rustc-option currently does not function when cross-compiling from x86_64 to aarch64 if CONFIG_SHADOW_CALL_STACK is enabled. This is because KBUILD_RUSTFLAGS contains -Zfixed-x18 under this configuration. Since that flag does not exist on the host target, rustc-option runs into a compilation failure every time, leading to all flags being rejected as unsupported. To fix this, update rustc-option to pass a --target parameter so that the host target is not used. For targets using target.json, use a built-in target that is as close as possible to the target created with target.json to avoid the circular dependency on target.json. One scenario where this causes a boot failure: * Cross-compiled from x86_64 to aarch64. * With CONFIG_SHADOW_CALL_STACK=y * With CONFIG_KASAN_SW_TAGS=y * With CONFIG_KASAN_INLINE=n Then the resulting kernel image will fail to boot when it first calls into Rust code with a crash along the lines of "Unable to handle kernel paging request at virtual address 0ffffffc08541796". This is because the call threshold is not specified, so rustc will inline kasan operations, but the kasan shadow offset is not specified, which leads to the inlined kasan instructions being incorrect. Note that the -Zsanitizer=kernel-hwaddress parameter itself does not lead to a rustc-option failure despite being aarch64-specific because RUSTFLAGS_KASAN has not yet been added to KBUILD_RUSTFLAGS when rustc-option is evaluated by the kasan Makefile. Cc: stable@vger.kernel.org Fixes: 46e24a545cdb ("rust: kasan/kbuild: fix missing flags on first build") Signed-off-by: Alice Ryhl Link: https://patch.msgid.link/20260507-rustc-option-cross-v2-1-2f650a49c2b5@google.com [ Edited slightly: - Reset variable to avoid using the environment. - Use a simply expanded variable flavor for simplicity. - Export variable so that behavior in sub-`make`s is consistent. This matches other variables. - Miguel ] Signed-off-by: Miguel Ojeda

x86/fpu: Remove MATH_EMULATION and related glue code

2026-05-08T05:33:03+00:00

Now that support for 486 CPUs is gone upstream, remove the x86 mathemu code integration. Signed-off-by: Ingo Molnar Reviewed-by: Arnd Bergmann Acked-by: Dave Hansen Cc: Linus Torvalds Link: https://lore.kernel.org/r/20250425084216.3913608-9-mingo@kernel.org

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

x86/entry/vdso: Update the object paths for "make vdso_install"

2026-01-16T20:58:45+00:00

The location of the vdso binary files in the object tree has changed; update "make vdso_install" to match. Closes: https://lore.kernel.org/16ea64d1-2a9b-46f9-9fcc-42958f599eb6@leemhuis.info Fixes: 693c819fedcd ("x86/entry/vdso: Refactor the vdso build") Reported-by: Thorsten Leemhuis Signed-off-by: H. Peter Anvin (Intel) Signed-off-by: Dave Hansen Link: https://patch.msgid.link/20260116204057.386268-2-hpa@zytor.com

x86/entry/vdso: Move vdso2c to arch/x86/tools

2026-01-13T23:33:20+00:00

It is generally better to build tools in arch/x86/tools to keep host cflags proliferation down, and to reduce makefile sequencing issues. Move the vdso build tool vdso2c into arch/x86/tools in preparation for refactoring the vdso makefiles. Signed-off-by: H. Peter Anvin (Intel) Signed-off-by: Dave Hansen Link: https://patch.msgid.link/20251216212606.1325678-3-hpa@zytor.com

Merge tag 'vfs-6.19-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2025-12-01T16:44:26+00:00

Pull misc vfs updates from Christian Brauner: "Features: - Cheaper MAY_EXEC handling for path lookup. This elides MAY_WRITE permission checks during path lookup and adds the IOP_FASTPERM_MAY_EXEC flag so filesystems like btrfs can avoid expensive permission work. - Hide dentry_cache behind runtime const machinery. - Add German Maglione as virtiofs co-maintainer. Cleanups: - Tidy up and inline step_into() and walk_component() for improved code generation. - Re-enable IOCB_NOWAIT writes to files. This refactors file timestamp update logic, fixing a layering bypass in btrfs when updating timestamps on device files and improving FMODE_NOCMTIME handling in VFS now that nfsd started using it. - Path lookup optimizations extracting slowpaths into dedicated routines and adding branch prediction hints for mntput_no_expire(), fd_install(), lookup_slow(), and various other hot paths. - Enable clang's -fms-extensions flag, requiring a JFS rename to avoid conflicts. - Remove spurious exports in fs/file_attr.c. - Stop duplicating union pipe_index declaration. This depends on the shared kbuild branch that brings in -fms-extensions support which is merged into this branch. - Use MD5 library instead of crypto_shash in ecryptfs. - Use largest_zero_folio() in iomap_dio_zero(). - Replace simple_strtol/strtoul with kstrtoint/kstrtouint in init and initrd code. - Various typo fixes. Fixes: - Fix emergency sync for btrfs. Btrfs requires an explicit sync_fs() call with wait == 1 to commit super blocks. The emergency sync path never passed this, leaving btrfs data uncommitted during emergency sync. - Use local kmap in watch_queue's post_one_notification(). - Add hint prints in sb_set_blocksize() for LBS dependency on THP" * tag 'vfs-6.19-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (35 commits) MAINTAINERS: add German Maglione as virtiofs co-maintainer fs: inline step_into() and walk_component() fs: tidy up step_into() & friends before inlining orangefs: use inode_update_timestamps directly btrfs: fix the comment on btrfs_update_time btrfs: use vfs_utimes to update file timestamps fs: export vfs_utimes fs: lift the FMODE_NOCMTIME check into file_update_time_flags fs: refactor file timestamp update logic include/linux/fs.h: trivial fix: regualr -> regular fs/splice.c: trivial fix: pipes -> pipe's fs: mark lookup_slow() as noinline fs: add predicts based on nd->depth fs: move mntput_no_expire() slowpath into a dedicated routine fs: remove spurious exports in fs/file_attr.c watch_queue: Use local kmap in post_one_notification() fs: touch up predicts in path lookup fs: move fd_install() slowpath into a dedicated routine and provide commentary fs: hide dentry_cache behind runtime const machinery fs: touch predicts in do_dentry_open() ...

rust: kbuild: support `-Cjump-tables=n` for Rust 1.93.0

2025-11-04T18:11:39+00:00

Rust 1.93.0 (expected 2026-01-22) is stabilizing `-Zno-jump-tables` [1][2] as `-Cjump-tables=n` [3]. Without this change, one would eventually see: RUSTC L rust/core.o error: unknown unstable option: `no-jump-tables` Thus support the upcoming version. Link: https://github.com/rust-lang/rust/issues/116592 [1] Link: https://github.com/rust-lang/rust/pull/105812 [2] Link: https://github.com/rust-lang/rust/pull/145974 [3] Reviewed-by: Alice Ryhl Reviewed-by: Trevor Gross Acked-by: Nicolas Schier Link: https://patch.msgid.link/20251101094011.1024534-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda