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2024-03-31kconfig: Fix typo HEIGTH to HEIGHTIsak Ellmer8-14/+14
Fixed a typo in some variables where height was misspelled as heigth. Signed-off-by: Isak Ellmer <isak01@gmail.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-03-31Documentation/llvm: Note s390 LLVM=1 support with LLVM 18.1.0 and newerNathan Chancellor1-1/+1
As of the first s390 pull request during the 6.9 merge window, commit 691632f0e869 ("Merge tag 's390-6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux"), s390 can be built with LLVM=1 when using LLVM 18.1.0, which is the first version that has SystemZ support implemented in ld.lld and llvm-objcopy. Update the supported architectures table in the Kbuild LLVM documentation to note this explicitly to make it more discoverable by users and other developers. Additionally, this brings s390 in line with the rest of the architectures in the table, which all support LLVM=1. Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-03-31kbuild: Disable KCSAN for autogenerated *.mod.c intermediariesBorislav Petkov (AMD)1-1/+1
When KCSAN and CONSTRUCTORS are enabled, one can trigger the "Unpatched return thunk in use. This should not happen!" catch-all warning. Usually, when objtool runs on the .o objects, it does generate a section .return_sites which contains all offsets in the objects to the return thunks of the functions present there. Those return thunks then get patched at runtime by the alternatives. KCSAN and CONSTRUCTORS add this to the object file's .text.startup section: ------------------- Disassembly of section .text.startup: ... 0000000000000010 <_sub_I_00099_0>: 10: f3 0f 1e fa endbr64 14: e8 00 00 00 00 call 19 <_sub_I_00099_0+0x9> 15: R_X86_64_PLT32 __tsan_init-0x4 19: e9 00 00 00 00 jmp 1e <__UNIQUE_ID___addressable_cryptd_alloc_aead349+0x6> 1a: R_X86_64_PLT32 __x86_return_thunk-0x4 ------------------- which, if it is built as a module goes through the intermediary stage of creating a <module>.mod.c file which, when translated, receives a second constructor: ------------------- Disassembly of section .text.startup: 0000000000000010 <_sub_I_00099_0>: 10: f3 0f 1e fa endbr64 14: e8 00 00 00 00 call 19 <_sub_I_00099_0+0x9> 15: R_X86_64_PLT32 __tsan_init-0x4 19: e9 00 00 00 00 jmp 1e <_sub_I_00099_0+0xe> 1a: R_X86_64_PLT32 __x86_return_thunk-0x4 ... 0000000000000030 <_sub_I_00099_0>: 30: f3 0f 1e fa endbr64 34: e8 00 00 00 00 call 39 <_sub_I_00099_0+0x9> 35: R_X86_64_PLT32 __tsan_init-0x4 39: e9 00 00 00 00 jmp 3e <__ksymtab_cryptd_alloc_ahash+0x2> 3a: R_X86_64_PLT32 __x86_return_thunk-0x4 ------------------- in the .ko file. Objtool has run already so that second constructor's return thunk cannot be added to the .return_sites section and thus the return thunk remains unpatched and the warning rightfully fires. Drop KCSAN flags from the mod.c generation stage as those constructors do not contain data races one would be interested about. Debugged together with David Kaplan <David.Kaplan@amd.com> and Nikolay Borisov <nik.borisov@suse.com>. Reported-by: Paul Menzel <pmenzel@molgen.mpg.de> Closes: https://lore.kernel.org/r/0851a207-7143-417e-be31-8bf2b3afb57d@molgen.mpg.de Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Tested-by: Paul Menzel <pmenzel@molgen.mpg.de> # Dell XPS 13 Reviewed-by: Nikolay Borisov <nik.borisov@suse.com> Reviewed-by: Marco Elver <elver@google.com> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-03-31kbuild: make -Woverride-init warnings more consistentArnd Bergmann13-23/+18
The -Woverride-init warn about code that may be intentional or not, but the inintentional ones tend to be real bugs, so there is a bit of disagreement on whether this warning option should be enabled by default and we have multiple settings in scripts/Makefile.extrawarn as well as individual subsystems. Older versions of clang only supported -Wno-initializer-overrides with the same meaning as gcc's -Woverride-init, though all supported versions now work with both. Because of this difference, an earlier cleanup of mine accidentally turned the clang warning off for W=1 builds and only left it on for W=2, while it's still enabled for gcc with W=1. There is also one driver that only turns the warning off for newer versions of gcc but not other compilers, and some but not all the Makefiles still use a cc-disable-warning conditional that is no longer needed with supported compilers here. Address all of the above by removing the special cases for clang and always turning the warning off unconditionally where it got in the way, using the syntax that is supported by both compilers. Fixes: 2cd3271b7a31 ("kbuild: avoid duplicate warning options") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com> Acked-by: Jani Nikula <jani.nikula@intel.com> Acked-by: Andrew Jeffery <andrew@codeconstruct.com.au> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-03-30objtool: Fix compile failure when using the x32 compilerMikulas Patocka1-1/+1
When compiling the v6.9-rc1 kernel with the x32 compiler, the following errors are reported. The reason is that we take an "unsigned long" variable and print it using "PRIx64" format string. In file included from check.c:16: check.c: In function ‘add_dead_ends’: /usr/src/git/linux-2.6/tools/objtool/include/objtool/warn.h:46:17: error: format ‘%llx’ expects argument of type ‘long long unsigned int’, but argument 5 has type ‘long unsigned int’ [-Werror=format=] 46 | "%s: warning: objtool: " format "\n", \ | ^~~~~~~~~~~~~~~~~~~~~~~~ check.c:613:33: note: in expansion of macro ‘WARN’ 613 | WARN("can't find unreachable insn at %s+0x%" PRIx64, | ^~~~ ... Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: linux-kernel@vger.kernel.org
2024-03-30x86/build: Use obj-y to descend into arch/x86/virt/Masahiro Yamada3-4/+2
Commit c33621b4c5ad ("x86/virt/tdx: Wire up basic SEAMCALL functions") introduced a new instance of core-y instead of the standardized obj-y syntax. X86 Makefiles descend into subdirectories of arch/x86/virt inconsistently; into arch/x86/virt/ via core-y defined in arch/x86/Makefile, but into arch/x86/virt/svm/ via obj-y defined in arch/x86/Kbuild. This is problematic when you build a single object in parallel because multiple threads attempt to build the same file. $ make -j$(nproc) arch/x86/virt/vmx/tdx/seamcall.o [ snip ] AS arch/x86/virt/vmx/tdx/seamcall.o AS arch/x86/virt/vmx/tdx/seamcall.o fixdep: error opening file: arch/x86/virt/vmx/tdx/.seamcall.o.d: No such file or directory make[4]: *** [scripts/Makefile.build:362: arch/x86/virt/vmx/tdx/seamcall.o] Error 2 Use the obj-y syntax, as it works correctly. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20240330060554.18524-1-masahiroy@kernel.org