summaryrefslogtreecommitdiff
path: root/Makefile
AgeCommit message (Collapse)Author
2025-04-13Linux 6.15-rc2Linus Torvalds
2025-04-08kbuild: Add '-fno-builtin-wcslen'Nathan Chancellor
A recent optimization change in LLVM [1] aims to transform certain loop idioms into calls to strlen() or wcslen(). This change transforms the first while loop in UniStrcat() into a call to wcslen(), breaking the build when UniStrcat() gets inlined into alloc_path_with_tree_prefix(): ld.lld: error: undefined symbol: wcslen >>> referenced by nls_ucs2_utils.h:54 (fs/smb/client/../../nls/nls_ucs2_utils.h:54) >>> vmlinux.o:(alloc_path_with_tree_prefix) >>> referenced by nls_ucs2_utils.h:54 (fs/smb/client/../../nls/nls_ucs2_utils.h:54) >>> vmlinux.o:(alloc_path_with_tree_prefix) Disable this optimization with '-fno-builtin-wcslen', which prevents the compiler from assuming that wcslen() is available in the kernel's C library. [ More to the point - it's not that we couldn't implement wcslen(), it's that this isn't an optimization at all in the context of the kernel. Replacing a simple inlined loop with a function call to the same loop is just stupid and pointless if you don't have long strings and fancy libraries with vectorization support etc. For the regular 'strlen()' cases, we want the compiler to do this in order to handle the trivial case of constant strings. And we do have optimized versions of 'strlen()' on some architectures. But for wcslen? Just no. - Linus ] Cc: stable@vger.kernel.org Link: https://github.com/llvm/llvm-project/commit/9694844d7e36fd5e01011ab56b64f27b867aa72d [1] Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2025-04-06Linux 6.15-rc1Linus Torvalds
2025-04-05Merge tag 'kbuild-v6.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Improve performance in gendwarfksyms - Remove deprecated EXTRA_*FLAGS and KBUILD_ENABLE_EXTRA_GCC_CHECKS - Support CONFIG_HEADERS_INSTALL for ARCH=um - Use more relative paths to sources files for better reproducibility - Support the loong64 Debian architecture - Add Kbuild bash completion - Introduce intermediate vmlinux.unstripped for architectures that need static relocations to be stripped from the final vmlinux - Fix versioning in Debian packages for -rc releases - Treat missing MODULE_DESCRIPTION() as an error - Convert Nios2 Makefiles to use the generic rule for built-in DTB - Add debuginfo support to the RPM package * tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (40 commits) kbuild: rpm-pkg: build a debuginfo RPM kconfig: merge_config: use an empty file as initfile nios2: migrate to the generic rule for built-in DTB rust: kbuild: skip `--remap-path-prefix` for `rustdoc` kbuild: pacman-pkg: hardcode module installation path kbuild: deb-pkg: don't set KBUILD_BUILD_VERSION unconditionally modpost: require a MODULE_DESCRIPTION() kbuild: make all file references relative to source root x86: drop unnecessary prefix map configuration kbuild: deb-pkg: add comment about future removal of KDEB_COMPRESS kbuild: Add a help message for "headers" kbuild: deb-pkg: remove "version" variable in mkdebian kbuild: deb-pkg: fix versioning for -rc releases Documentation/kbuild: Fix indentation in modules.rst example x86: Get rid of Makefile.postlink kbuild: Create intermediate vmlinux build with relocations preserved kbuild: Introduce Kconfig symbol for linking vmlinux with relocations kbuild: link-vmlinux.sh: Make output file name configurable kbuild: do not generate .tmp_vmlinux*.map when CONFIG_VMLINUX_MAP=y Revert "kheaders: Ignore silly-rename files" ...
2025-03-24Merge tag 'x86-core-2025-03-22' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull core x86 updates from Ingo Molnar: "x86 CPU features support: - Generate the <asm/cpufeaturemasks.h> header based on build config (H. Peter Anvin, Xin Li) - x86 CPUID parsing updates and fixes (Ahmed S. Darwish) - Introduce the 'setcpuid=' boot parameter (Brendan Jackman) - Enable modifying CPU bug flags with '{clear,set}puid=' (Brendan Jackman) - Utilize CPU-type for CPU matching (Pawan Gupta) - Warn about unmet CPU feature dependencies (Sohil Mehta) - Prepare for new Intel Family numbers (Sohil Mehta) Percpu code: - Standardize & reorganize the x86 percpu layout and related cleanups (Brian Gerst) - Convert the stackprotector canary to a regular percpu variable (Brian Gerst) - Add a percpu subsection for cache hot data (Brian Gerst) - Unify __pcpu_op{1,2}_N() macros to __pcpu_op_N() (Uros Bizjak) - Construct __percpu_seg_override from __percpu_seg (Uros Bizjak) MM: - Add support for broadcast TLB invalidation using AMD's INVLPGB instruction (Rik van Riel) - Rework ROX cache to avoid writable copy (Mike Rapoport) - PAT: restore large ROX pages after fragmentation (Kirill A. Shutemov, Mike Rapoport) - Make memremap(MEMREMAP_WB) map memory as encrypted by default (Kirill A. Shutemov) - Robustify page table initialization (Kirill A. Shutemov) - Fix flush_tlb_range() when used for zapping normal PMDs (Jann Horn) - Clear _PAGE_DIRTY for kernel mappings when we clear _PAGE_RW (Matthew Wilcox) KASLR: - x86/kaslr: Reduce KASLR entropy on most x86 systems, to support PCI BAR space beyond the 10TiB region (CONFIG_PCI_P2PDMA=y) (Balbir Singh) CPU bugs: - Implement FineIBT-BHI mitigation (Peter Zijlstra) - speculation: Simplify and make CALL_NOSPEC consistent (Pawan Gupta) - speculation: Add a conditional CS prefix to CALL_NOSPEC (Pawan Gupta) - RFDS: Exclude P-only parts from the RFDS affected list (Pawan Gupta) System calls: - Break up entry/common.c (Brian Gerst) - Move sysctls into arch/x86 (Joel Granados) Intel LAM support updates: (Maciej Wieczor-Retman) - selftests/lam: Move cpu_has_la57() to use cpuinfo flag - selftests/lam: Skip test if LAM is disabled - selftests/lam: Test get_user() LAM pointer handling AMD SMN access updates: - Add SMN offsets to exclusive region access (Mario Limonciello) - Add support for debugfs access to SMN registers (Mario Limonciello) - Have HSMP use SMN through AMD_NODE (Yazen Ghannam) Power management updates: (Patryk Wlazlyn) - Allow calling mwait_play_dead with an arbitrary hint - ACPI/processor_idle: Add FFH state handling - intel_idle: Provide the default enter_dead() handler - Eliminate mwait_play_dead_cpuid_hint() Build system: - Raise the minimum GCC version to 8.1 (Brian Gerst) - Raise the minimum LLVM version to 15.0.0 (Nathan Chancellor) Kconfig: (Arnd Bergmann) - Add cmpxchg8b support back to Geode CPUs - Drop 32-bit "bigsmp" machine support - Rework CONFIG_GENERIC_CPU compiler flags - Drop configuration options for early 64-bit CPUs - Remove CONFIG_HIGHMEM64G support - Drop CONFIG_SWIOTLB for PAE - Drop support for CONFIG_HIGHPTE - Document CONFIG_X86_INTEL_MID as 64-bit-only - Remove old STA2x11 support - Only allow CONFIG_EISA for 32-bit Headers: - Replace __ASSEMBLY__ with __ASSEMBLER__ in UAPI and non-UAPI headers (Thomas Huth) Assembly code & machine code patching: - x86/alternatives: Simplify alternative_call() interface (Josh Poimboeuf) - x86/alternatives: Simplify callthunk patching (Peter Zijlstra) - KVM: VMX: Use named operands in inline asm (Josh Poimboeuf) - x86/hyperv: Use named operands in inline asm (Josh Poimboeuf) - x86/traps: Cleanup and robustify decode_bug() (Peter Zijlstra) - x86/kexec: Merge x86_32 and x86_64 code using macros from <asm/asm.h> (Uros Bizjak) - Use named operands in inline asm (Uros Bizjak) - Improve performance by using asm_inline() for atomic locking instructions (Uros Bizjak) Earlyprintk: - Harden early_serial (Peter Zijlstra) NMI handler: - Add an emergency handler in nmi_desc & use it in nmi_shootdown_cpus() (Waiman Long) Miscellaneous fixes and cleanups: - by Ahmed S. Darwish, Andy Shevchenko, Ard Biesheuvel, Artem Bityutskiy, Borislav Petkov, Brendan Jackman, Brian Gerst, Dan Carpenter, Dr. David Alan Gilbert, H. Peter Anvin, Ingo Molnar, Josh Poimboeuf, Kevin Brodsky, Mike Rapoport, Lukas Bulwahn, Maciej Wieczor-Retman, Max Grobecker, Patryk Wlazlyn, Pawan Gupta, Peter Zijlstra, Philip Redkin, Qasim Ijaz, Rik van Riel, Thomas Gleixner, Thorsten Blum, Tom Lendacky, Tony Luck, Uros Bizjak, Vitaly Kuznetsov, Xin Li, liuye" * tag 'x86-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (211 commits) zstd: Increase DYNAMIC_BMI2 GCC version cutoff from 4.8 to 11.0 to work around compiler segfault x86/asm: Make asm export of __ref_stack_chk_guard unconditional x86/mm: Only do broadcast flush from reclaim if pages were unmapped perf/x86/intel, x86/cpu: Replace Pentium 4 model checks with VFM ones perf/x86/intel, x86/cpu: Simplify Intel PMU initialization x86/headers: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-UAPI headers x86/headers: Replace __ASSEMBLY__ with __ASSEMBLER__ in UAPI headers x86/locking/atomic: Improve performance by using asm_inline() for atomic locking instructions x86/asm: Use asm_inline() instead of asm() in clwb() x86/asm: Use CLFLUSHOPT and CLWB mnemonics in <asm/special_insns.h> x86/hweight: Use asm_inline() instead of asm() x86/hweight: Use ASM_CALL_CONSTRAINT in inline asm() x86/hweight: Use named operands in inline asm() x86/stackprotector/64: Only export __ref_stack_chk_guard on CONFIG_SMP x86/head/64: Avoid Clang < 17 stack protector in startup code x86/kexec: Merge x86_32 and x86_64 code using macros from <asm/asm.h> x86/runtime-const: Add the RUNTIME_CONST_PTR assembly macro x86/cpu/intel: Limit the non-architectural constant_tsc model checks x86/mm/pat: Replace Intel x86_model checks with VFM ones x86/cpu/intel: Fix fast string initialization for extended Families ...
2025-03-24Linux 6.14Linus Torvalds
2025-03-22kbuild: make all file references relative to source rootThomas Weißschuh
-fmacro-prefix-map only affects __FILE__ and __BASE_FILE__. Other references, for example in debug information, are not affected. This makes handling of file references in the compiler outputs harder to use and creates problems for reproducible builds. Switch to -ffile-prefix map which affects all references. Also drop the documentation section advising manual specification of -fdebug-prefix-map for reproducible builds, as it is not necessary anymore. Suggested-by: Ben Hutchings <ben@decadent.org.uk> Link: https://lore.kernel.org/lkml/c49cc967294f9a3a4a34f69b6a8727a6d3959ed8.camel@decadent.org.uk/ Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2025-03-22kbuild: Add a help message for "headers"Xin Li (Intel)
Meanwhile explicitly state that the headers are uapi headers. Suggested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Xin Li (Intel) <xin@zytor.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2025-03-19Merge tag 'v6.14-rc7' into x86/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-03-16Linux 6.14-rc7Linus Torvalds
2025-03-17kbuild: Create intermediate vmlinux build with relocations preservedArd Biesheuvel
The imperative paradigm used to build vmlinux, extract some info from it or perform some checks on it, and subsequently modify it again goes against the declarative paradigm that is usually employed for defining make rules. In particular, the Makefile.postlink files that consume their input via an output rule result in some dodgy logic in the decompressor makefiles for RISC-V and x86, given that the vmlinux.relocs input file needed to generate the arch-specific relocation tables may not exist or be out of date, but cannot be constructed using the ordinary Make dependency based rules, because the info needs to be extracted while vmlinux is in its ephemeral, non-stripped form. So instead, for architectures that require the static relocations that are emitted into vmlinux when passing --emit-relocs to the linker, and are subsequently stripped out again, introduce an intermediate vmlinux target called vmlinux.unstripped, and organize the reset of the build logic accordingly: - vmlinux.unstripped is created only once, and not updated again - build rules under arch/*/boot can depend on vmlinux.unstripped without running the risk of the data disappearing or being out of date - the final vmlinux generated by the build is not bloated with static relocations that are never needed again after the build completes. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2025-03-17kbuild: Introduce Kconfig symbol for linking vmlinux with relocationsArd Biesheuvel
Some architectures build vmlinux with static relocations preserved, but strip them again from the final vmlinux image. Arch specific tools consume these static relocations in order to construct relocation tables for KASLR. The fact that vmlinux is created, consumed and subsequently updated goes against the typical, declarative paradigm used by Make, which is based on rules and dependencies. So as a first step towards cleaning this up, introduce a Kconfig symbol to declare that the arch wants to consume the static relocations emitted into vmlinux. This will be wired up further in subsequent patches. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2025-03-15kbuild, rust: use -fremap-path-prefix to make paths relativeThomas Weißschuh
Remap source path prefixes in all output, including compiler diagnostics, debug information, macro expansions, etc. This removes a few absolute paths from the binary and also makes it possible to use core::panic::Location properly. Equivalent to the same configuration done for C sources in commit 1d3730f0012f ("kbuild: support -fmacro-prefix-map for external modules") and commit a73619a845d5 ("kbuild: use -fmacro-prefix-map to make __FILE__ a relative path"). Link: https://doc.rust-lang.org/rustc/command-line-arguments.html#--remap-path-prefix-remap-source-names-in-output Acked-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Tested-by: Gary Guo <gary@garyguo.net> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2025-03-15kbuild: implement CONFIG_HEADERS_INSTALL for Usermode LinuxThomas Weißschuh
userprogs sometimes need access to UAPI headers. This is currently not possible for Usermode Linux, as UM is only a pseudo architecture built on top of a regular architecture and does not have its own UAPI. Instead use the UAPI headers from the underlying regular architecture. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2025-03-15kbuild: remove KBUILD_ENABLE_EXTRA_GCC_CHECKS supportMasahiro Yamada
Commit e27128db6283 ("kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN") renamed KBUILD_ENABLE_EXTRA_GCC_CHECKS in 2019. The migration in downstream code should be complete. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nathan Chancellor <nathan@kernel.org>
2025-03-15kbuild: move -fzero-init-padding-bits=all to the top-level MakefileMasahiro Yamada
The -fzero-init-padding-bits=all option is not a warning flag, so defining it in scripts/Makefile.extrawarn is inconsistent. Move it to the top-level Makefile for consistency. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org>
2025-03-09Linux 6.14-rc6Linus Torvalds
2025-03-05kbuild: userprogs: use correct lld when linking through clangThomas Weißschuh
The userprog infrastructure links objects files through $(CC). Either explicitly by manually calling $(CC) on multiple object files or implicitly by directly compiling a source file to an executable. The documentation at Documentation/kbuild/llvm.rst indicates that ld.lld would be used for linking if LLVM=1 is specified. However clang instead will use either a globally installed cross linker from $PATH called ${target}-ld or fall back to the system linker, which probably does not support crosslinking. For the normal kernel build this is not an issue because the linker is always executed directly, without the compiler being involved. Explicitly pass --ld-path to clang so $(LD) is respected. As clang 13.0.1 is required to build the kernel, this option is available. Fixes: 7f3a59db274c ("kbuild: add infrastructure to build userspace programs") Cc: stable@vger.kernel.org # needs wrapping in $(cc-option) for < 6.9 Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2025-03-03Merge tag 'v6.14-rc5' into x86/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-03-02Linux 6.14-rc5Linus Torvalds
2025-02-26x86/ibt: Implement FineIBT-BHI mitigationPeter Zijlstra
While WAIT_FOR_ENDBR is specified to be a full speculation stop; it has been shown that some implementations are 'leaky' to such an extend that speculation can escape even the FineIBT preamble. To deal with this, add additional hardening to the FineIBT preamble. Notably, using a new LLVM feature: https://github.com/llvm/llvm-project/commit/e223485c9b38a5579991b8cebb6a200153eee245 which encodes the number of arguments in the kCFI preamble's register. Using this register<->arity mapping, have the FineIBT preamble CALL into a stub clobbering the relevant argument registers in the speculative case. Scott sayeth thusly: Microarchitectural attacks such as Branch History Injection (BHI) and Intra-mode Branch Target Injection (IMBTI) [1] can cause an indirect call to mispredict to an adversary-influenced target within the same hardware domain (e.g., within the kernel). Instructions at the mispredicted target may execute speculatively and potentially expose kernel data (e.g., to a user-mode adversary) through a microarchitectural covert channel such as CPU cache state. CET-IBT [2] is a coarse-grained control-flow integrity (CFI) ISA extension that enforces that each indirect call (or indirect jump) must land on an ENDBR (end branch) instruction, even speculatively*. FineIBT is a software technique that refines CET-IBT by associating each function type with a 32-bit hash and enforcing (at the callee) that the hash of the caller's function pointer type matches the hash of the callee's function type. However, recent research [3] has demonstrated that the conditional branch that enforces FineIBT's hash check can be coerced to mispredict, potentially allowing an adversary to speculatively bypass the hash check: __cfi_foo: ENDBR64 SUB R10d, 0x01234567 JZ foo # Even if the hash check fails and ZF=0, this branch could still mispredict as taken UD2 foo: ... The techniques demonstrated in [3] require the attacker to be able to control the contents of at least one live register at the mispredicted target. Therefore, this patch set introduces a sequence of CMOV instructions at each indirect-callable target that poisons every live register with data that the attacker cannot control whenever the FineIBT hash check fails, thus mitigating any potential attack. The security provided by this scheme has been discussed in detail on an earlier thread [4]. [1] https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/branch-history-injection.html [2] Intel Software Developer's Manual, Volume 1, Chapter 18 [3] https://www.vusec.net/projects/native-bhi/ [4] https://lore.kernel.org/lkml/20240927194925.707462984@infradead.org/ *There are some caveats for certain processors, see [1] for more info Suggested-by: Scott Constable <scott.d.constable@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Kees Cook <kees@kernel.org> Link: https://lore.kernel.org/r/20250224124200.820402212@infradead.org
2025-02-23Linux 6.14-rc4Linus Torvalds
2025-02-16Linux 6.14-rc3Linus Torvalds
2025-02-16kbuild: userprogs: fix bitsize and target detection on clangThomas Weißschuh
scripts/Makefile.clang was changed in the linked commit to move --target from KBUILD_CFLAGS to KBUILD_CPPFLAGS, as that generally has a broader scope. However that variable is not inspected by the userprogs logic, breaking cross compilation on clang. Use both variables to detect bitsize and target arguments for userprogs. Fixes: feb843a469fb ("kbuild: add $(CLANG_FLAGS) to KBUILD_CPPFLAGS") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2025-02-15tools: fix annoying "mkdir -p ..." logs when building tools in parallelMasahiro Yamada
When CONFIG_OBJTOOL=y or CONFIG_DEBUG_INFO_BTF=y, parallel builds show awkward "mkdir -p ..." logs. $ make -j16 [ snip ] mkdir -p /home/masahiro/ref/linux/tools/objtool && make O=/home/masahiro/ref/linux subdir=tools/objtool --no-print-directory -C objtool mkdir -p /home/masahiro/ref/linux/tools/bpf/resolve_btfids && make O=/home/masahiro/ref/linux subdir=tools/bpf/resolve_btfids --no-print-directory -C bpf/resolve_btfids Defining MAKEFLAGS=<value> on the command line wipes out command line switches from the resultant MAKEFLAGS definition, even though the command line switches are active. [1] MAKEFLAGS puts all single-letter options into the first word, and that word will be empty if no single-letter options were given. [2] However, this breaks if MAKEFLAGS=<value> is given on the command line. The tools/ and tools/% targets set MAKEFLAGS=<value> on the command line, which breaks the following code in tools/scripts/Makefile.include: short-opts := $(firstword -$(MAKEFLAGS)) If MAKEFLAGS really needs modification, it should be done through the environment variable, as follows: MAKEFLAGS=<value> $(MAKE) ... That said, I question whether modifying MAKEFLAGS is necessary here. The only flag we might want to exclude is --no-print-directory, as the tools build system changes the working directory. However, people might find the "Entering/Leaving directory" logs annoying. I simply removed the offending MAKEFLAGS=<value>. [1]: https://savannah.gnu.org/bugs/?62469 [2]: https://www.gnu.org/software/make/manual/make.html#Testing-Flags Fixes: ea01fa9f63ae ("tools: Connect to the kernel build system") Fixes: a50e43332756 ("perf tools: Honor parallel jobs") Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Tested-by: Daniel Xu <dxu@dxuuu.xyz>
2025-02-09Linux 6.14-rc2Linus Torvalds
2025-02-02Linux 6.14-rc1Linus Torvalds
2025-01-22Merge tag 'net-next-6.14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Paolo Abeni: "This is slightly smaller than usual, with the most interesting work being still around RTNL scope reduction. Core: - More core refactoring to reduce the RTNL lock contention, including preparatory work for the per-network namespace RTNL lock, replacing RTNL lock with a per device-one to protect NAPI-related net device data and moving synchronize_net() calls outside such lock. - Extend drop reasons usage, adding net scheduler, AF_UNIX, bridge and more specific TCP coverage. - Reduce network namespace tear-down time by removing per-subsystems synchronize_net() in tipc and sched. - Add flow label selector support for fib rules, allowing traffic redirection based on such header field. Netfilter: - Do not remove netdev basechain when last device is gone, allowing netdev basechains without devices. - Revisit the flowtable teardown strategy, dealing better with fin, reset and re-open events. - Scale-up IP-vs connection dumping by avoiding linear search on each restart. Protocols: - A significant XDP socket refactor, consolidating and optimizing several helpers into the core - Better scaling of ICMP rate-limiting, by removing false-sharing in inet peers handling. - Introduces netlink notifications for multicast IPv4 and IPv6 address changes. - Add ipsec support for IP-TFS/AggFrag encapsulation, allowing aggregation and fragmentation of the inner IP. - Add sysctl to configure TIME-WAIT reuse delay for TCP sockets, to avoid local port exhaustion issues when the average connection lifetime is very short. - Support updating keys (re-keying) for connections using kernel TLS (for TLS 1.3 only). - Support ipv4-mapped ipv6 address clients in smc-r v2. - Add support for jumbo data packet transmission in RxRPC sockets, gluing multiple data packets in a single UDP packet. - Support RxRPC RACK-TLP to manage packet loss and retransmission in conjunction with the congestion control algorithm. Driver API: - Introduce a unified and structured interface for reporting PHY statistics, exposing consistent data across different H/W via ethtool. - Make timestamping selectable, allow the user to select the desired hwtstamp provider (PHY or MAC) administratively. - Add support for configuring a header-data-split threshold (HDS) value via ethtool, to deal with partial or buggy H/W implementation. - Consolidate DSA drivers Energy Efficiency Ethernet support. - Add EEE management to phylink, making use of the phylib implementation. - Add phylib support for in-band capabilities negotiation. - Simplify how phylib-enabled mac drivers expose the supported interfaces. Tests and tooling: - Make the YNL tool package-friendly to make it easier to deploy it separately from the kernel. - Increase TCP selftest coverage importing several packetdrill test-cases. - Regenerate the ethtool uapi header from the YNL spec, to ease maintenance and future development. - Add YNL support for decoding the link types used in net self-tests, allowing a single build to run both net and drivers/net. Drivers: - Ethernet high-speed NICs: - nVidia/Mellanox (mlx5): - add cross E-Switch QoS support - add SW Steering support for ConnectX-8 - implement support for HW-Managed Flow Steering, improving the rule deletion/insertion rate - support for multi-host LAG - Intel (ixgbe, ice, igb): - ice: add support for devlink health events - ixgbe: add initial support for E610 chipset variant - igb: add support for AF_XDP zero-copy - Meta: - add support for basic RSS config - allow changing the number of channels - add hardware monitoring support - Broadcom (bnxt): - implement TCP data split and HDS threshold ethtool support, enabling Device Memory TCP. - Marvell Octeon: - implement egress ipsec offload support for the cn10k family - Hisilicon (HIBMC): - implement unicast MAC filtering - Ethernet NICs embedded and virtual: - Convert UDP tunnel drivers to NETDEV_PCPU_STAT_DSTATS, avoiding contented atomic operations for drop counters - Freescale: - quicc: phylink conversion - enetc: support Tx and Rx checksum offload and improve TSO performances - MediaTek: - airoha: introduce support for ETS and HTB Qdisc offload - Microchip: - lan78XX USB: preparation work for phylink conversion - Synopsys (stmmac): - support DWMAC IP on NXP Automotive SoCs S32G2xx/S32G3xx/S32R45 - refactor EEE support to leverage the new driver API - optimize DMA and cache access to increase raw RX performances by 40% - TI: - icssg-prueth: add multicast filtering support for VLAN interface - netkit: - add ability to configure head/tailroom - VXLAN: - accepts packets with user-defined reserved bit - Ethernet switches: - Microchip: - lan969x: add RGMII support - lan969x: improve TX and RX performance using the FDMA engine - nVidia/Mellanox: - move Tx header handling to PCI driver, to ease XDP support - Ethernet PHYs: - Texas Instruments DP83822: - add support for GPIO2 clock output - Realtek: - 8169: add support for RTL8125D rev.b - rtl822x: add hwmon support for the temperature sensor - Microchip: - add support for RDS PTP hardware - consolidate periodic output signal generation - CAN: - several DT-bindings to DT schema conversions - tcan4x5x: - add HW standby support - support nWKRQ voltage selection - kvaser: - allowing Bus Error Reporting runtime configuration - WiFi: - the on-going Multi-Link Operation (MLO) effort continues, affecting both the stack and in drivers - mac80211/cfg80211: - Emergency Preparedness Communication Services (EPCS) station mode support - support for adding and removing station links for MLO - add support for WiFi 7/EHT mesh over 320 MHz channels - report Tx power info for each link - RealTek (rtw88): - enable USB Rx aggregation and USB 3 to improve performance - LED support - RealTek (rtw89): - refactor power save to support Multi-Link Operations - add support for RTL8922AE-VS variant - MediaTek (mt76): - single wiphy multiband support (preparation for MLO) - p2p device support - add TP-Link TXE50UH USB adapter support - Qualcomm (ath10k): - support for the QCA6698AQ IP core - Qualcomm (ath12k): - enable MLO for QCN9274 - Bluetooth: - Allow sysfs to trigger hdev reset, to allow recovering devices not responsive from user-space - MediaTek: add support for MT7922, MT7925, MT7921e devices - Realtek: add support for RTL8851BE devices - Qualcomm: add support for WCN785x devices - ISO: allow BIG re-sync" * tag 'net-next-6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1386 commits) net/rose: prevent integer overflows in rose_setsockopt() net: phylink: fix regression when binding a PHY net: ethernet: ti: am65-cpsw: streamline TX queue creation and cleanup net: ethernet: ti: am65-cpsw: streamline RX queue creation and cleanup net: ethernet: ti: am65-cpsw: ensure proper channel cleanup in error path ipv6: Convert inet6_rtm_deladdr() to per-netns RTNL. ipv6: Convert inet6_rtm_newaddr() to per-netns RTNL. ipv6: Move lifetime validation to inet6_rtm_newaddr(). ipv6: Set cfg.ifa_flags before device lookup in inet6_rtm_newaddr(). ipv6: Pass dev to inet6_addr_add(). ipv6: Convert inet6_ioctl() to per-netns RTNL. ipv6: Hold rtnl_net_lock() in addrconf_init() and addrconf_cleanup(). ipv6: Hold rtnl_net_lock() in addrconf_dad_work(). ipv6: Hold rtnl_net_lock() in addrconf_verify_work(). ipv6: Convert net.ipv6.conf.${DEV}.XXX sysctl to per-netns RTNL. ipv6: Add __in6_dev_get_rtnl_net(). net: stmmac: Drop redundant skb_mark_for_recycle() for SKB frags net: mii: Fix the Speed display when the network cable is not connected sysctl net: Remove macro checks for CONFIG_SYSCTL eth: bnxt: update header sizing defaults ...
2025-01-21Merge tag 'rust-6.14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux Pull rust updates from Miguel Ojeda: "Toolchain and infrastructure: - Finish the move to custom FFI integer types started in the previous cycle and finally map 'long' to 'isize' and 'char' to 'u8'. Do a few cleanups on top thanks to that. - Start to use 'derive(CoercePointee)' on Rust >= 1.84.0. This is a major milestone on the path to build the kernel using only stable Rust features. In particular, previously we were using the unstable features 'coerce_unsized', 'dispatch_from_dyn' and 'unsize', and now we will use the new 'derive_coerce_pointee' one, which is on track to stabilization. This new feature is a macro that essentially expands into code that internally uses the unstable features that we were using before, without having to expose those. With it, stable Rust users, including the kernel, will be able to build custom smart pointers that work with trait objects, e.g.: fn f(p: &Arc<dyn Display>) { pr_info!("{p}\n"); } let a: Arc<dyn Display> = Arc::new(42i32, GFP_KERNEL)?; let b: Arc<dyn Display> = Arc::new("hello there", GFP_KERNEL)?; f(&a); // Prints "42". f(&b); // Prints "hello there". Together with the 'arbitrary_self_types' feature that we started using in the previous cycle, using our custom smart pointers like 'Arc' will eventually only rely in stable Rust. - Introduce 'PROCMACROLDFLAGS' environment variable to allow to link Rust proc macros using different flags than those used for linking Rust host programs (e.g. when 'rustc' uses a different C library than the host programs' one), which Android needs. - Help kernel builds under macOS with Rust enabled by accomodating other naming conventions for dynamic libraries (i.e. '.so' vs. '.dylib') which are used for Rust procedural macros. The actual support for macOS (i.e. the rest of the pieces needed) is provided out-of-tree by others, following the policy used for other parts of the kernel by Kbuild. - Run Clippy for 'rusttest' code too and clean the bits it spotted. - Provide Clippy with the minimum supported Rust version to improve the suggestions it gives. - Document 'bindgen' 0.71.0 regression. 'kernel' crate: - 'build_error!': move users of the hidden function to the documented macro, prevent such uses in the future by moving the function elsewhere and add the macro to the prelude. - 'types' module: add improved version of 'ForeignOwnable::borrow_mut' (which was removed in the past since it was problematic); change 'ForeignOwnable' pointer type to '*mut'. - 'alloc' module: implement 'Display' for 'Box' and align the 'Debug' implementation to it; add example (doctest) for 'ArrayLayout::new()' - 'sync' module: document 'PhantomData' in 'Arc'; use 'NonNull::new_unchecked' in 'ForeignOwnable for Arc' impl. - 'uaccess' module: accept 'Vec's with different allocators in 'UserSliceReader::read_all'. - 'workqueue' module: enable run-testing a couple more doctests. - 'error' module: simplify 'from_errno()'. - 'block' module: fix formatting in code documentation (a lint to catch these is being implemented). - Avoid 'unwrap()'s in doctests, which also improves the examples by showing how kernel code is supposed to be written. - Avoid 'as' casts with 'cast{,_mut}' calls which are a bit safer. And a few other cleanups" * tag 'rust-6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (32 commits) kbuild: rust: add PROCMACROLDFLAGS rust: uaccess: generalize userSliceReader to support any Vec rust: kernel: add improved version of `ForeignOwnable::borrow_mut` rust: kernel: reorder `ForeignOwnable` items rust: kernel: change `ForeignOwnable` pointer to mut rust: arc: split unsafe block, add missing comment rust: types: avoid `as` casts rust: arc: use `NonNull::new_unchecked` rust: use derive(CoercePointee) on rustc >= 1.84.0 rust: alloc: add doctest for `ArrayLayout::new()` rust: init: update `stack_try_pin_init` examples rust: error: import `kernel`'s `LayoutError` instead of `core`'s rust: str: replace unwraps with question mark operators rust: page: remove unnecessary helper function from doctest rust: rbtree: remove unwrap in asserts rust: init: replace unwraps with question mark operators rust: use host dylib naming convention to support macOS rust: add `build_error!` to the prelude rust: kernel: move `build_error` hidden function to prevent mistakes rust: use the `build_error!` macro, not the hidden function ...
2025-01-19Linux 6.13Linus Torvalds
2025-01-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-6.13-rc8). Conflicts: drivers/net/ethernet/realtek/r8169_main.c 1f691a1fc4be ("r8169: remove redundant hwmon support") 152d00a91396 ("r8169: simplify setting hwmon attribute visibility") https://lore.kernel.org/20250115122152.760b4e8d@canb.auug.org.au Adjacent changes: drivers/net/ethernet/broadcom/bnxt/bnxt.c 152f4da05aee ("bnxt_en: add support for rx-copybreak ethtool command") f0aa6a37a3db ("eth: bnxt: always recalculate features after XDP clearing, fix null-deref") drivers/net/ethernet/intel/ice/ice_type.h 50327223a8bb ("ice: add lock to protect low latency interface") dc26548d729e ("ice: Fix quad registers read on E825") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-15kbuild: rust: add PROCMACROLDFLAGSHONG Yifan
These are flags to be passed when linking proc macros for the Rust toolchain. If unset, it defaults to $(KBUILD_HOSTLDFLAGS). This is needed because the list of flags to link hostprogs is not necessarily the same as the list of flags used to link libmacros.so. When we build proc macros, we need the latter, not the former (e.g. when using a Rust compiler binary linked to a different C library than host programs). To distinguish between the two, introduce this new variable to stand out from KBUILD_HOSTLDFLAGS used to link other host progs. Signed-off-by: HONG Yifan <elsk@google.com> Link: https://lore.kernel.org/r/20241017210430.2401398-2-elsk@google.com [ v3: - `export`ed the variable. Otherwise it would not be visible in `rust/Makefile`. - Removed "additional" from the documentation and commit message, since this actually replaces the other flags, unlike other cases. - Added example of use case to documentation and commit message. Thanks Alice for the details on what Google needs! - Instead of `HOSTLDFLAGS`, used `KBUILD_HOSTLDFLAGS` as the fallback to preserve the previous behavior as much as possible, as discussed with Alice/Yifan. Thus moved the variable down too (currently we do not modify `KBUILD_HOSTLDFLAGS` elsewhere) and avoided mentioning `HOSTLDFLAGS` directly in the documentation. - Fixed documentation header formatting. - Reworded slightly. - Miguel ] Tested-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: HONG Yifan <elsk@google.com> Acked-by: Masahiro Yamada <masahiroy@kernel.org> Link: https://lore.kernel.org/r/20241112184455.855133-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-01-12Linux 6.13-rc7Linus Torvalds
2025-01-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-6.13-rc7). Conflicts: a42d71e322a8 ("net_sched: sch_cake: Add drop reasons") 737d4d91d35b ("sched: sch_cake: add bounds checks to host bulk flow fairness counts") Adjacent changes: drivers/net/ethernet/meta/fbnic/fbnic.h 3a856ab34726 ("eth: fbnic: add IRQ reuse support") 95978931d55f ("eth: fbnic: Revert "eth: fbnic: Add hardware monitoring support via HWMON interface"") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-10rust: use host dylib naming convention to support macOSTamir Duberstein
Because the `macros` crate exposes procedural macros, it must be compiled as a dynamic library (so it can be loaded by the compiler at compile-time). Before this change the resulting artifact was always named `libmacros.so`, which works on hosts where this matches the naming convention for dynamic libraries. However the proper name on macOS would be `libmacros.dylib`. This turns out to matter even when the dependency is passed with a path (`--extern macros=path/to/libmacros.so` rather than `--extern macros`) because rustc uses the file name to infer the type of the library (see link). This is because there's no way to specify both the path to and the type of the external library via CLI flags. The compiler could speculatively parse the file to determine its type, but it does not do so today. This means that libraries that match neither rustc's naming convention for static libraries nor the platform's naming convention for dynamic libraries are *rejected*. The only solution I've found is to follow the host platform's naming convention. This patch does that by querying the compiler to determine the appropriate name for the artifact. This allows the kernel to build with CONFIG_RUST=y on macOS. Link: https://github.com/rust-lang/rust/blob/d829780/compiler/rustc_metadata/src/locator.rs#L728-L752 Tested-by: Daniel Gomez <da.gomez@samsung.com> Co-developed-by: Fiona Behrens <me@kloenk.dev> Signed-off-by: Fiona Behrens <me@kloenk.dev> Signed-off-by: Tamir Duberstein <tamird@gmail.com> Tested-by: Andreas Hindborg <a.hindborg@kernel.org> Link: https://lore.kernel.org/r/20241216-b4-dylib-host-macos-v7-1-cfc507681447@gmail.com [ Added `MAKEFLAGS=`s to avoid jobserver warnings. Removed space. Reworded title. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-01-05Linux 6.13-rc6Linus Torvalds
2025-01-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-6.13-rc6). No conflicts. Adjacent changes: include/linux/if_vlan.h f91a5b808938 ("af_packet: fix vlan_get_protocol_dgram() vs MSG_PEEK") 3f330db30638 ("net: reformat kdoc return statements") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-29Linux 6.13-rc5Linus Torvalds
2024-12-22Linux 6.13-rc4Linus Torvalds
2024-12-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-6.13-rc4). No conflicts. Adjacent changes: drivers/net/ethernet/renesas/rswitch.h 32fd46f5b69e ("net: renesas: rswitch: remove speed from gwca structure") 922b4b955a03 ("net: renesas: rswitch: rework ts tags management") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-15Linux 6.13-rc3Linus Torvalds
2024-12-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR (net-6.13-rc3). No conflicts or adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-11lib: packing: add pack_fields() and unpack_fields()Vladimir Oltean
This is new API which caters to the following requirements: - Pack or unpack a large number of fields to/from a buffer with a small code footprint. The current alternative is to open-code a large number of calls to pack() and unpack(), or to use packing() to reduce that number to half. But packing() is not const-correct. - Use unpacked numbers stored in variables smaller than u64. This reduces the rodata footprint of the stored field arrays. - Perform error checking at compile time, rather than runtime, and return void from the API functions. Because the C preprocessor can't generate variable length code (loops), this is a bit tricky to do with macros. To handle this, implement macros which sanity check the packed field definitions based on their size. Finally, a single macro with a chain of __builtin_choose_expr() is used to select the appropriate macros. We enforce the use of ascending or descending order to avoid O(N^2) scaling when checking for overlap. Note that the macros are written with care to ensure that the compilers can correctly evaluate the resulting code at compile time. In particular, care was taken with avoiding too many nested statement expressions. Nested statement expressions trip up some compilers, especially when passing down variables created in previous statement expressions. There are two key design choices intended to keep the overall macro code size small. First, the definition of each CHECK_PACKED_FIELDS_N macro is implemented recursively, by calling the N-1 macro. This avoids needing the code to repeat multiple times. Second, the CHECK_PACKED_FIELD macro enforces that the fields in the array are sorted in order. This allows checking for overlap only with neighboring fields, rather than the general overlap case where each field would need to be checked against other fields. The overlap checks use the first two fields to determine the order of the remaining fields, thus allowing either ascending or descending order. This enables drivers the flexibility to keep the fields ordered in which ever order most naturally fits their hardware design and its associated documentation. The CHECK_PACKED_FIELDS macro is directly called from within pack_fields and unpack_fields, ensuring that all drivers using the API receive the benefits of the compile-time checks. Users do not need to directly call any of the macros directly. The CHECK_PACKED_FIELDS and its helper macros CHECK_PACKED_FIELDS_(0..50) are generated using a simple C program in scripts/gen_packed_field_checks.c This program can be compiled on demand and executed to generate the macro code in include/linux/packing.h. This will aid in the event that a driver needs more than 50 fields. The generator can be updated with a new size, and used to update the packing.h header file. In practice, the ice driver will need to support 27 fields, and the sja1105 driver will need to support 0 fields. This on-demand generation avoids the need to modify Kbuild. We do not anticipate the maximum number of fields to grow very often. - Reduced rodata footprint for the storage of the packed field arrays. To that end, we have struct packed_field_u8 and packed_field_u16, which define the fields with the associated type. More can be added as needed (unlikely for now). On these types, the same generic pack_fields() and unpack_fields() API can be used, thanks to the new C11 _Generic() selection feature, which can call pack_fields_u8() or pack_fields_16(), depending on the type of the "fields" array - a simplistic form of polymorphism. It is evaluated at compile time which function will actually be called. Over time, packing() is expected to be completely replaced either with pack() or with pack_fields(). Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Co-developed-by: Jacob Keller <jacob.e.keller@intel.com> Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com> Link: https://patch.msgid.link/20241210-packing-pack-fields-and-ice-implementation-v10-3-ee56a47479ac@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-08Linux 6.13-rc2Linus Torvalds
2024-12-01Linux 6.13-rc1Linus Torvalds
2024-11-30Merge tag 'kbuild-v6.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Add generic support for built-in boot DTB files - Enable TAB cycling for dialog buttons in nconfig - Fix issues in streamline_config.pl - Refactor Kconfig - Add support for Clang's AutoFDO (Automatic Feedback-Directed Optimization) - Add support for Clang's Propeller, a profile-guided optimization. - Change the working directory to the external module directory for M= builds - Support building external modules in a separate output directory - Enable objtool for *.mod.o and additional kernel objects - Use lz4 instead of deprecated lz4c - Work around a performance issue with "git describe" - Refactor modpost * tag 'kbuild-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (85 commits) kbuild: rename .tmp_vmlinux.kallsyms0.syms to .tmp_vmlinux0.syms gitignore: Don't ignore 'tags' directory kbuild: add dependency from vmlinux to resolve_btfids modpost: replace tdb_hash() with hash_str() kbuild: deb-pkg: add python3:native to build dependency genksyms: reduce indentation in export_symbol() modpost: improve error messages in device_id_check() modpost: rename alias symbol for MODULE_DEVICE_TABLE() modpost: rename variables in handle_moddevtable() modpost: move strstarts() to modpost.h modpost: convert do_usb_table() to a generic handler modpost: convert do_of_table() to a generic handler modpost: convert do_pnp_device_entry() to a generic handler modpost: convert do_pnp_card_entries() to a generic handler modpost: call module_alias_printf() from all do_*_entry() functions modpost: pass (struct module *) to do_*_entry() functions modpost: remove DEF_FIELD_ADDR_VAR() macro modpost: deduplicate MODULE_ALIAS() for all drivers modpost: introduce module_alias_printf() helper modpost: remove unnecessary check in do_acpi_entry() ...
2024-11-28kbuild: switch from lz4c to lz4 for compressionParth Pancholi
Replace lz4c with lz4 for kernel image compression. Although lz4 and lz4c are functionally similar, lz4c has been deprecated upstream since 2018. Since as early as Ubuntu 16.04 and Fedora 25, lz4 and lz4c have been packaged together, making it safe to update the requirement from lz4c to lz4. Consequently, some distributions and build systems, such as OpenEmbedded, have fully transitioned to using lz4. OpenEmbedded core adopted this change in commit fe167e082cbd ("bitbake.conf: require lz4 instead of lz4c"), causing compatibility issues when building the mainline kernel in the latest OpenEmbedded environment, as seen in the errors below. This change also updates the LZ4 compression commands to make it backward compatible by replacing stdin and stdout with the '-' option, due to some unclear reason, the stdout keyword does not work for lz4 and '-' works for both. In addition, this modifies the legacy '-c1' with '-9' which is also compatible with both. This fixes the mainline kernel build failures with the latest master OpenEmbedded builds associated with the mentioned compatibility issues. LZ4 arch/arm/boot/compressed/piggy_data /bin/sh: 1: lz4c: not found ... ... ERROR: oe_runmake failed Link: https://github.com/lz4/lz4/pull/553 Suggested-by: Francesco Dolcini <francesco.dolcini@toradex.com> Signed-off-by: Parth Pancholi <parth.pancholi@toradex.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-11-28kbuild: remove support for single %.symtypes build ruleMasahiro Yamada
This rule is unnecessary because you can generate foo/bar.symtypes as a side effect using: $ make KBUILD_SYMTYPES=1 foo/bar.o While compiling *.o is slower than preprocessing, the impact is negligible. I prioritize keeping the code simpler. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2024-11-28kbuild: allow to start building external modules in any directoryMasahiro Yamada
Unless an explicit O= option is provided, external module builds must start from the kernel directory. This can be achieved by using the -C option: $ make -C /path/to/kernel M=/path/to/external/module This commit allows starting external module builds from any directory, so you can also do the following: $ make -f /path/to/kernel/Makefile M=/path/to/external/module The key difference is that the -C option changes the working directory and parses the Makefile located there, while the -f option only specifies the Makefile to use. As shown in the examples in Documentation/kbuild/modules.rst, external modules usually have a wrapper Makefile that allows you to build them without specifying any make arguments. The Makefile typically contains a rule as follows: KDIR ?= /path/to/kernel default: $(MAKE) -C $(KDIR) M=$(CURDIR) $(MAKECMDGOALS) The log will appear as follows: $ make make -C /path/to/kernel M=/path/to/external/module make[1]: Entering directory '/path/to/kernel' make[2]: Entering directory '/path/to/external/module' CC [M] helloworld.o MODPOST Module.symvers CC [M] helloworld.mod.o CC [M] .module-common.o LD [M] helloworld.ko make[2]: Leaving directory '/path/to/external/module' make[1]: Leaving directory '/path/to/kernel' This changes the working directory twice because the -C option first switches to the kernel directory, and then Kbuild internally recurses back to the external module directory. With this commit, the wrapper Makefile can directly include the kernel Makefile: KDIR ?= /path/to/kernel export KBUILD_EXTMOD := $(realpath $(dir $(lastword $(MAKEFILE_LIST)))) include $(KDIR)/Makefile This avoids unnecessary sub-make invocations: $ make CC [M] helloworld.o MODPOST Module.symvers CC [M] helloworld.mod.o CC [M] .module-common.o LD [M] helloworld.ko Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2024-11-28kbuild: make wrapper Makefile more convenient for external modulesMasahiro Yamada
When Kbuild starts building in a separate output directory, it generates a wrapper Makefile, allowing you to invoke 'make' from the output directory. This commit makes it more convenient, so you can invoke 'make' without M= or MO=. First, you need to build external modules in a separate directory: $ make M=/path/to/module/source/dir MO=/path/to/module/build/dir Once the wrapper Makefile is generated in /path/to/module/build/dir, you can proceed as follows: $ cd /path/to/module/build/dir $ make Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
generated by cgit (git 2.34.1) at 2025-05-09 20:42:39 +0000