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path: root/tools/arch/x86/include/asm/nops.h
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2025-03-19x86/headers: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-UAPI headersThomas Huth
While the GCC and Clang compilers already define __ASSEMBLER__ automatically when compiling assembly code, __ASSEMBLY__ is a macro that only gets defined by the Makefiles in the kernel. This can be very confusing when switching between userspace and kernelspace coding, or when dealing with UAPI headers that rather should use __ASSEMBLER__ instead. So let's standardize on the __ASSEMBLER__ macro that is provided by the compilers now. This is mostly a mechanical patch (done with a simple "sed -i" statement), with some manual tweaks in <asm/frame.h>, <asm/hw_irq.h> and <asm/setup.h> that mentioned this macro in comments with some missing underscores. Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: Juergen Gross <jgross@suse.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lore.kernel.org/r/20250314071013.1575167-38-thuth@redhat.com
2023-05-31x86/alternatives: Add longer 64-bit NOPsPeter Zijlstra
By adding support for longer NOPs there are a few more alternatives that can turn into a single instruction. Add up to NOP11, the same limit where GNU as .nops also stops generating longer nops. This is because a number of uarchs have severe decode penalties for more than 3 prefixes. [ bp: Sync up with the version in tools/ while at it. ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Link: https://lore.kernel.org/r/20230515093020.661756940@infradead.org
2021-05-10x86/asm: Use _ASM_BYTES() in <asm/nops.h>H. Peter Anvin (Intel)
Use the new generalized _ASM_BYTES() macro from <asm/asm.h> instead of the "home grown" _ASM_MK_NOP() in <asm/nops.h>. Add <asm/asm.h> and update <asm/nops.h> in the tools directory... Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://lore.kernel.org/r/20210510090940.924953-4-hpa@zytor.com
2021-03-15objtool/x86: Use asm/nops.hPeter Zijlstra
Since the kernel will rely on a single canonical set of NOPs, make sure objtool uses the exact same ones. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Borislav Petkov <bp@suse.de> Link: https://lkml.kernel.org/r/20210312115749.136357911@infradead.org