linux/scripts, branch v6.15

kbuild: fix typos "module.builtin" to "modules.builtin"

2025-05-12T06:04:52Z

The filenames in the comments do not match the actual generated files. Signed-off-by: Masahiro Yamada

kbuild: fix dependency on sorttable

2025-05-12T06:04:09Z

Commit ac4f06789b4f ("kbuild: Create intermediate vmlinux build with relocations preserved") missed replacing one occurrence of "vmlinux" that was added during the same development cycle. Fixes: ac4f06789b4f ("kbuild: Create intermediate vmlinux build with relocations preserved") Signed-off-by: Masahiro Yamada Acked-by: Ard Biesheuvel

kbuild: Disable -Wdefault-const-init-unsafe

2025-05-12T06:03:17Z

A new on by default warning in clang [1] aims to flags instances where const variables without static or thread local storage or const members in aggregate types are not initialized because it can lead to an indeterminate value. This is quite noisy for the kernel due to instances originating from header files such as: drivers/gpu/drm/i915/gt/intel_ring.h:62:2: error: default initialization of an object of type 'typeof (ring->size)' (aka 'const unsigned int') leaves the object uninitialized [-Werror,-Wdefault-const-init-var-unsafe] 62 | typecheck(typeof(ring->size), next); | ^ include/linux/typecheck.h:10:9: note: expanded from macro 'typecheck' 10 | ({ type __dummy; \ | ^ include/net/ip.h:478:14: error: default initialization of an object of type 'typeof (rt->dst.expires)' (aka 'const unsigned long') leaves the object uninitialized [-Werror,-Wdefault-const-init-var-unsafe] 478 | if (mtu && time_before(jiffies, rt->dst.expires)) | ^ include/linux/jiffies.h:138:26: note: expanded from macro 'time_before' 138 | #define time_before(a,b) time_after(b,a) | ^ include/linux/jiffies.h:128:3: note: expanded from macro 'time_after' 128 | (typecheck(unsigned long, a) && \ | ^ include/linux/typecheck.h:11:12: note: expanded from macro 'typecheck' 11 | typeof(x) __dummy2; \ | ^ include/linux/list.h:409:27: warning: default initialization of an object of type 'union (unnamed union at include/linux/list.h:409:27)' with const member leaves the object uninitialized [-Wdefault-const-init-field-unsafe] 409 | struct list_head *next = smp_load_acquire(&head->next); | ^ include/asm-generic/barrier.h:176:29: note: expanded from macro 'smp_load_acquire' 176 | #define smp_load_acquire(p) __smp_load_acquire(p) | ^ arch/arm64/include/asm/barrier.h:164:59: note: expanded from macro '__smp_load_acquire' 164 | union { __unqual_scalar_typeof(*p) __val; char __c[1]; } __u; \ | ^ include/linux/list.h:409:27: note: member '__val' declared 'const' here crypto/scatterwalk.c:66:22: error: default initialization of an object of type 'struct scatter_walk' with const member leaves the object uninitialized [-Werror,-Wdefault-const-init-field-unsafe] 66 | struct scatter_walk walk; | ^ include/crypto/algapi.h:112:15: note: member 'addr' declared 'const' here 112 | void *const addr; | ^ fs/hugetlbfs/inode.c:733:24: error: default initialization of an object of type 'struct vm_area_struct' with const member leaves the object uninitialized [-Werror,-Wdefault-const-init-field-unsafe] 733 | struct vm_area_struct pseudo_vma; | ^ include/linux/mm_types.h:803:20: note: member 'vm_flags' declared 'const' here 803 | const vm_flags_t vm_flags; | ^ Silencing the instances from typecheck.h is difficult because '= {}' is not available in older but supported compilers and '= {0}' would cause warnings about a literal 0 being treated as NULL. While it might be possible to come up with a local hack to silence the warning for clang-21+, it may not be worth it since -Wuninitialized will still trigger if an uninitialized const variable is actually used. In all audited cases of the "field" variant of the warning, the members are either not used in the particular call path, modified through other means such as memset() / memcpy() because the containing object is not const, or are within a union with other non-const members. Since this warning does not appear to have a high signal to noise ratio, just disable it. Cc: stable@vger.kernel.org Link: https://github.com/llvm/llvm-project/commit/576161cb6069e2c7656a8ef530727a0f4aefff30 [1] Reported-by: Linux Kernel Functional Testing Closes: https://lore.kernel.org/CA+G9fYuNjKcxFKS_MKPRuga32XbndkLGcY-PVuoSwzv6VWbY=w@mail.gmail.com/ Reported-by: Marcus Seyfarth Closes: https://github.com/ClangBuiltLinux/linux/issues/2088 Signed-off-by: Nathan Chancellor Signed-off-by: Masahiro Yamada

kbuild: rpm-pkg: Add (elfutils-devel or libdw-devel) to BuildRequires

2025-05-12T06:03:17Z

The dwarf.h header, which is included by scripts/gendwarfksyms/gendwarfksyms.h, resides within elfutils-devel or libdw-devel package. This portion of the code is compiled under the condition that CONFIG_GENDWARFKSYMS is enabled. Consequently, add (elfutils-devel or libdw-devel) to BuildRequires to prevent unforeseen compilation failures. Fix follow possible error: In file included from scripts/gendwarfksyms/cache.c:6: scripts/gendwarfksyms/gendwarfksyms.h:6:10: fatal error: 'dwarf.h' file not found 6 | #include | ^~~~~~~~~ Link: https://lore.kernel.org/all/3e52d80d-0c60-4df5-8cb5-21d4b1fce7b7@suse.com/ Fixes: f28568841ae0 ("tools: Add gendwarfksyms") Suggested-by: Petr Pavlu Signed-off-by: WangYuli Reviewed-by: Nicolas Schier Signed-off-by: Masahiro Yamada

kbuild: deb-pkg: Add libdw-dev:native to Build-Depends-Arch

2025-05-12T06:03:17Z

The dwarf.h header, which is included by scripts/gendwarfksyms/gendwarfksyms.h, resides within the libdw-dev package. This portion of the code is compiled under the condition that CONFIG_GENDWARFKSYMS is enabled. Consequently, add libdw-dev to Build-Depends-Arch to prevent unforeseen compilation failures. Fix follow possible error: In file included from scripts/gendwarfksyms/symbols.c:6: scripts/gendwarfksyms/gendwarfksyms.h:6:10: fatal error: 'dwarf.h' file not found 6 | #include | ^~~~~~~~~ Fixes: f28568841ae0 ("tools: Add gendwarfksyms") Reviewed-by: Sami Tolvanen Signed-off-by: WangYuli Reviewed-by: Nicolas Schier Tested-by: Nicolas Schier Signed-off-by: Masahiro Yamada

scripts: Do not strip .rela.dyn section

2025-05-08T12:01:01Z

The .rela.dyn section contains runtime relocations and is only emitted for a relocatable kernel. riscv uses this section to relocate the kernel at runtime but that section is stripped from vmlinux. That prevents kexec to successfully load vmlinux since it does not contain the relocations info needed. Fixes: 559d1e45a16d ("riscv: Use --emit-relocs in order to move .rela.dyn in init") Tested-by: Björn Töpel Reviewed-by: Björn Töpel Acked-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20250408072851.90275-1-alexghiti@rivosinc.com Signed-off-by: Alexandre Ghiti

kbuild: Properly disable -Wunterminated-string-initialization for clang

2025-05-01T01:57:56Z

Clang and GCC have different behaviors around disabling warnings included in -Wall and -Wextra and the order in which flags are specified, which is exposed by clang's new support for -Wunterminated-string-initialization. $ cat test.c const char foo[3] = "FOO"; const char bar[3] __attribute__((__nonstring__)) = "BAR"; $ clang -fsyntax-only -Wextra test.c test.c:1:21: warning: initializer-string for character array is too long, array size is 3 but initializer has size 4 (including the null terminating character); did you mean to use the 'nonstring' attribute? [-Wunterminated-string-initialization] 1 | const char foo[3] = "FOO"; | ^~~~~ $ clang -fsyntax-only -Wextra -Wno-unterminated-string-initialization test.c $ clang -fsyntax-only -Wno-unterminated-string-initialization -Wextra test.c test.c:1:21: warning: initializer-string for character array is too long, array size is 3 but initializer has size 4 (including the null terminating character); did you mean to use the 'nonstring' attribute? [-Wunterminated-string-initialization] 1 | const char foo[3] = "FOO"; | ^~~~~ $ gcc -fsyntax-only -Wextra test.c test.c:1:21: warning: initializer-string for array of ‘char’ truncates NUL terminator but destination lacks ‘nonstring’ attribute (4 chars into 3 available) [-Wunterminated-string-initialization] 1 | const char foo[3] = "FOO"; | ^~~~~ $ gcc -fsyntax-only -Wextra -Wno-unterminated-string-initialization test.c $ gcc -fsyntax-only -Wno-unterminated-string-initialization -Wextra test.c Move -Wextra up right below -Wall in Makefile.extrawarn to ensure these flags are at the beginning of the warning options list. Move the couple of warning options that have been added to the main Makefile since commit e88ca24319e4 ("kbuild: consolidate warning flags in scripts/Makefile.extrawarn") to scripts/Makefile.extrawarn after -Wall / -Wextra to ensure they get properly disabled for all compilers. Fixes: 9d7a0577c9db ("gcc-15: disable '-Wunterminated-string-initialization' entirely for now") Link: https://github.com/llvm/llvm-project/issues/10359 Signed-off-by: Nathan Chancellor Signed-off-by: Linus Torvalds

Fix mis-uses of 'cc-option' for warning disablement

2025-04-23T17:08:29Z

This was triggered by one of my mis-uses causing odd build warnings on sparc in linux-next, but while figuring out why the "obviously correct" use of cc-option caused such odd breakage, I found eight other cases of the same thing in the tree. The root cause is that 'cc-option' doesn't work for checking negative warning options (ie things like '-Wno-stringop-overflow') because gcc will silently accept options it doesn't recognize, and so 'cc-option' ends up thinking they are perfectly fine. And it all works, until you have a situation where _another_ warning is emitted. At that point the compiler will go "Hmm, maybe the user intended to disable this warning but used that wrong option that I didn't recognize", and generate a warning for the unrecognized negative option. Which explains why we have several cases of this in the tree: the 'cc-option' test really doesn't work for this situation, but most of the time it simply doesn't matter that ity doesn't work. The reason my recently added case caused problems on sparc was pointed out by Thomas Weißschuh: the sparc build had a previous explicit warning that then triggered the new one. I think the best fix for this would be to make 'cc-option' a bit smarter about this sitation, possibly by adding an intentional warning to the test case that then triggers the unrecognized option warning reliably. But the short-term fix is to replace 'cc-option' with an existing helper designed for this exact case: 'cc-disable-warning', which picks the negative warning but uses the positive form for testing the compiler support. Reported-by: Stephen Rothwell Link: https://lore.kernel.org/all/20250422204718.0b4e3f81@canb.auug.org.au/ Explained-by: Thomas Weißschuh Signed-off-by: Linus Torvalds

Merge tag 'rust-fixes-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux

2025-04-19T17:02:43Z

Pull rust fixes from Miguel Ojeda: "Toolchain and infrastructure: - Fix missing KASAN LLVM flags on first build (and fix spurious rebuilds) by skipping '--target' - Fix Make < 4.3 build error by using '$(pound)' - Fix UML build error by removing 'volatile' qualifier from io helpers - Fix UML build error by adding 'dma_{alloc,free}_attrs()' helpers - Clean gendwarfksyms warnings by avoiding to export '__pfx' symbols - Clean objtool warning by adding a new 'noreturn' function for 1.86.0 - Disable 'needless_continue' Clippy lint due to new 1.86.0 warnings - Add missing 'ffi' crate to 'generate_rust_analyzer.py' 'pin-init' crate: - Import a couple fixes from upstream" * tag 'rust-fixes-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: rust: helpers: Add dma_alloc_attrs() and dma_free_attrs() rust: helpers: Remove volatile qualifier from io helpers rust: kbuild: use `pound` to support GNU Make < 4.3 objtool/rust: add one more `noreturn` Rust function for Rust 1.86.0 rust: kasan/kbuild: fix missing flags on first build rust: disable `clippy::needless_continue` rust: kbuild: Don't export __pfx symbols rust: pin-init: use Markdown autolinks in Rust comments rust: pin-init: alloc: restrict `impl ZeroableOption` for `Box` to `T: Sized` scripts: generate_rust_analyzer: Add ffi crate

rust: kbuild: use `pound` to support GNU Make < 4.3

2025-04-15T18:45:46Z

GNU Make 4.3 changed the behavior of `#` inside commands in commit c6966b323811 ("[SV 20513] Un-escaped # are not comments in function invocations"): * WARNING: Backward-incompatibility! Number signs (#) appearing inside a macro reference or function invocation no longer introduce comments and should not be escaped with backslashes: thus a call such as: foo := $(shell echo '#') is legal. Previously the number sign needed to be escaped, for example: foo := $(shell echo '\#') Now this latter will resolve to "\#". If you want to write makefiles portable to both versions, assign the number sign to a variable: H := \# foo := $(shell echo '$H') This was claimed to be fixed in 3.81, but wasn't, for some reason. To detect this change search for 'nocomment' in the .FEATURES variable. Unlike other commits in the kernel about this issue, such as commit 633174a7046e ("lib/raid6/test/Makefile: Use $(pound) instead of \# for Make 4.3"), that fixed the issue for newer GNU Makes, in our case it was the opposite, i.e. we need to fix it for the older ones: someone building with e.g. 4.2.1 gets the following error: scripts/Makefile.compiler:81: *** unterminated call to function 'call': missing ')'. Stop. Thus use the existing variable to fix it. Reported-by: moyi geek <1441339168@qq.com> Closes: https://rust-for-linux.zulipchat.com/#narrow/channel/291565/topic/x/near/512001985 Cc: stable@vger.kernel.org Fixes: e72a076c620f ("kbuild: fix issues with rustc-option") Reviewed-by: Nicolas Schier Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20250414171241.2126137-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda