user/sven/linux.git/arch/loongarch/vdso, branch master

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

2026-04-14T16:18:40Z

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 ...

LoongArch: vDSO: Emit GNU_EH_FRAME correctly

2026-03-26T06:29:09Z

With -fno-asynchronous-unwind-tables and --no-eh-frame-hdr (the default of the linker), the GNU_EH_FRAME segment (specified by vdso.lds.S) is empty. This is not valid, as the current DWARF specification mandates the first byte of the EH frame to be the version number 1. It causes some unwinders to complain, for example the ClickHouse query profiler spams the log with messages: clickhouse-server[365854]: libunwind: unsupported .eh_frame_hdr version: 127 at 7ffffffb0000 Here "127" is just the byte located at the p_vaddr (0, i.e. the beginning of the vDSO) of the empty GNU_EH_FRAME segment. Cross- checking with /proc/365854/maps has also proven 7ffffffb0000 is the start of vDSO in the process VM image. In LoongArch the -fno-asynchronous-unwind-tables option seems just a MIPS legacy, and MIPS only uses this option to satisfy the MIPS-specific "genvdso" program, per the commit cfd75c2db17e ("MIPS: VDSO: Explicitly use -fno-asynchronous-unwind-tables"). IIRC it indicates some inherent limitation of the MIPS ELF ABI and has nothing to do with LoongArch. So we can simply flip it over to -fasynchronous-unwind-tables and pass --eh-frame-hdr for linking the vDSO, allowing the profilers to unwind the stack for statistics even if the sample point is taken when the PC is in the vDSO. However simply adjusting the options above would exploit an issue: when the libgcc unwinder saw the invalid GNU_EH_FRAME segment, it silently falled back to a machine-specific routine to match the code pattern of rt_sigreturn() and extract the registers saved in the sigframe if the code pattern is matched. As unwinding from signal handlers is vital for libgcc to support pthread cancellation etc., the fall-back routine had been silently keeping the LoongArch Linux systems functioning since Linux 5.19. But when we start to emit GNU_EH_FRAME with the correct format, fall-back routine will no longer be used and libgcc will fail to unwind the sigframe, and unwinding from signal handlers will no longer work, causing dozens of glibc test failures. To make it possible to unwind from signal handlers again, it's necessary to code the unwind info in __vdso_rt_sigreturn via .cfi_* directives. The offsets in the .cfi_* directives depend on the layout of struct sigframe, notably the offset of sigcontext in the sigframe. To use the offset in the assembly file, factor out struct sigframe into a header to allow asm-offsets.c to output the offset for assembly. To work around a long-term issue in the libgcc unwinder (the pc is unconditionally substracted by 1: doing so is technically incorrect for a signal frame), a nop instruction is included with the two real instructions in __vdso_rt_sigreturn in the same FDE PC range. The same hack has been used on x86 for a long time. Cc: stable@vger.kernel.org Fixes: c6b99bed6b8f ("LoongArch: Add VDSO and VSYSCALL support") Signed-off-by: Xi Ruoyao Signed-off-by: Huacai Chen

kbuild: Consolidate C dialect options

2026-03-12T11:52:37Z

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

vdso: Remove struct getcpu_cache

2026-01-14T07:56:40Z

The cache parameter of getcpu() is useless nowadays for various reasons. * It is never passed by userspace for either the vDSO or syscalls. * It is never used by the kernel. * It could not be made to work on the current vDSO architecture. * The structure definition is not part of the UAPI headers. * vdso_getcpu() is superseded by restartable sequences in any case. Remove the struct and its header. As a side-effect this gets rid of an unwanted inclusion of the linux/ header namespace from vDSO code. [ tglx: Adapt to s390 upstream changes */ Signed-off-by: Thomas Weißschuh Signed-off-by: Thomas Gleixner Acked-by: Arnd Bergmann Acked-by: Heiko Carstens # s390 Link: https://patch.msgid.link/20251230-getcpu_cache-v3-1-fb9c5f880ebe@linutronix.de

Merge tag 'loongarch-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

2025-12-12T17:44:03Z

Pull LoongArch updates from Huacai Chen: - Add basic LoongArch32 support Note: Build infrastructures of LoongArch32 are not enabled yet, because we need to adjust irqchip drivers and wait for GNU toolchain be upstream first. - Select HAVE_ARCH_BITREVERSE in Kconfig - Fix build and boot for CONFIG_RANDSTRUCT - Correct the calculation logic of thread_count - Some bug fixes and other small changes * tag 'loongarch-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: (22 commits) LoongArch: Adjust default config files for 32BIT/64BIT LoongArch: Adjust VDSO/VSYSCALL for 32BIT/64BIT LoongArch: Adjust misc routines for 32BIT/64BIT LoongArch: Adjust user accessors for 32BIT/64BIT LoongArch: Adjust system call for 32BIT/64BIT LoongArch: Adjust module loader for 32BIT/64BIT LoongArch: Adjust time routines for 32BIT/64BIT LoongArch: Adjust process management for 32BIT/64BIT LoongArch: Adjust memory management for 32BIT/64BIT LoongArch: Adjust boot & setup for 32BIT/64BIT LoongArch: Adjust common macro definitions for 32BIT/64BIT LoongArch: Add adaptive CSR accessors for 32BIT/64BIT LoongArch: Add atomic operations for 32BIT/64BIT LoongArch: Add new PCI ID for pci_fixup_vgadev() LoongArch: Add and use some macros for AVEC LoongArch: Correct the calculation logic of thread_count LoongArch: Use unsigned long for _end and _text LoongArch: Use __pmd()/__pte() for swap entry conversions LoongArch: Fix arch_dup_task_struct() for CONFIG_RANDSTRUCT LoongArch: Fix build errors for CONFIG_RANDSTRUCT ...

LoongArch: Adjust VDSO/VSYSCALL for 32BIT/64BIT

2025-12-08T10:09:17Z

Adjust VDSO/VSYSCALL because read_cpu_id() for 32BIT/64BIT are different, and LoongArch32 doesn't support GENERIC_GETTIMEOFDAY now (will be supported in future). Reviewed-by: Arnd Bergmann Signed-off-by: Jiaxun Yang Signed-off-by: Huacai Chen

kbuild: Add '-fms-extensions' to areas with dedicated CFLAGS

2025-10-31T01:26:28Z

This is a follow up to commit c4781dc3d1cf ("Kbuild: enable -fms-extensions") but in a separate change due to being substantially different from the initial submission. There are many places within the kernel that use their own CFLAGS instead of the main KBUILD_CFLAGS, meaning code written with the main kernel's use of '-fms-extensions' in mind that may be tangentially included in these areas will result in "error: declaration does not declare anything" messages from the compiler. Add '-fms-extensions' to all these areas to ensure consistency, along with -Wno-microsoft-anon-tag to silence clang's warning about use of the extension that the kernel cares about using. parisc does not build with clang so it does not need this warning flag. LoongArch does not need it either because -W flags from KBUILD_FLAGS are pulled into cflags-vdso. Reported-by: Christian Brauner Closes: https://lore.kernel.org/20251030-meerjungfrau-getrocknet-7b46eacc215d@brauner/ Reviewed-by: Christian Brauner Acked-by: Ard Biesheuvel Signed-off-by: Nathan Chancellor

LoongArch: vDSO: Remove -nostdlib complier flag

2025-08-05T11:00:22Z

Since $(LD) is directly used, hence -nostdlib is unneeded, MIPS has removed this, we should remove it too. bdbf2038fbf4 ("MIPS: VDSO: remove -nostdlib compiler flag"). In fact, other architectures also use $(LD) now. fe00e50b2db8 ("ARM: 8858/1: vdso: use $(LD) instead of $(CC) to link VDSO") 691efbedc60d ("arm64: vdso: use $(LD) instead of $(CC) to link VDSO") 2ff906994b6c ("MIPS: VDSO: Use $(LD) instead of $(CC) to link VDSO") 2b2a25845d53 ("s390/vdso: Use $(LD) instead of $(CC) to link vDSO") Cc: stable@vger.kernel.org Reviewed-by: Yanteng Si Signed-off-by: Wentao Guan Signed-off-by: Huacai Chen

Merge tag 'loongarch-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson

2025-04-02T19:15:01Z

Pull LoongArch updates from Huacai Chen: - Always select HAVE_VIRT_CPU_ACCOUNTING_GEN - Enable UBSAN (Undefined Behavior Sanitizer) - Increase MAX_IO_PICS up to 8 - Increase ARCH_DMA_MINALIGN up to 16 - Fix and improve BPF JIT - Fix and improve vDSO implementation - Update the default config file - Some bug fixes and other small changes * tag 'loongarch-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson: LoongArch: Update Loongson-3 default config file LoongArch: vDSO: Make use of the t8 register for vgetrandom-chacha LoongArch: vDSO: Remove --hash-style=sysv LoongArch: BPF: Don't override subprog's return value LoongArch: BPF: Use move_addr() for BPF_PSEUDO_FUNC LoongArch: BPF: Fix off-by-one error in build_prologue() LoongArch: Rework the arch_kgdb_breakpoint() implementation LoongArch: Fix device node refcount leak in fdt_cpu_clk_init() LoongArch: Increase ARCH_DMA_MINALIGN up to 16 LoongArch: Increase MAX_IO_PICS up to 8 LoongArch: Fix help text of CMDLINE_EXTEND in Kconfig LoongArch: Enable UBSAN (Undefined Behavior Sanitizer) LoongArch: Always select HAVE_VIRT_CPU_ACCOUNTING_GEN rust: Fix enabling Rust and building with GCC for LoongArch

LoongArch: vDSO: Make use of the t8 register for vgetrandom-chacha

2025-03-30T08:31:12Z

Make use of the t8 register for vgetrandom-chacha, so we don't need to reuse a register and rematerialize a constant. I Signed-off-by: Xi Ruoyao Signed-off-by: Huacai Chen