19336376bd
Now that the minimum supported version of LLVM for building the kernel has
been bumped to 13.0.1, the conditional expression added to get_current()
by commit c1e42efacb ("ARM: 9151/1: Thumb2: avoid
__builtin_thread_pointer() on Clang") is always true, as the build will
fail during the configuration stage for older LLVM versions. Remove it,
effectively reverting the aforementioned change.
Link: https://lkml.kernel.org/r/20240125-bump-min-llvm-ver-to-13-0-1-v1-4-f5ff9bda41c5@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Conor Dooley <conor@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
65 lines
1.8 KiB
C
65 lines
1.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Copyright (c) 2021 Keith Packard <keithp@keithp.com>
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* Copyright (c) 2021 Google, LLC <ardb@kernel.org>
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*/
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#ifndef _ASM_ARM_CURRENT_H
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#define _ASM_ARM_CURRENT_H
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#ifndef __ASSEMBLY__
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#include <asm/insn.h>
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struct task_struct;
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extern struct task_struct *__current;
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static __always_inline __attribute_const__ struct task_struct *get_current(void)
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{
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struct task_struct *cur;
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#if __has_builtin(__builtin_thread_pointer) && defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO)
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/*
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* Use the __builtin helper when available - this results in better
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* code, especially when using GCC in combination with the per-task
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* stack protector, as the compiler will recognize that it needs to
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* load the TLS register only once in every function.
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*/
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cur = __builtin_thread_pointer();
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#elif defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP)
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asm("0: mrc p15, 0, %0, c13, c0, 3 \n\t"
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#ifdef CONFIG_CPU_V6
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"1: \n\t"
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" .subsection 1 \n\t"
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#if defined(CONFIG_ARM_HAS_GROUP_RELOCS) && \
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!(defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS))
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"2: " LOAD_SYM_ARMV6(%0, __current) " \n\t"
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" b 1b \n\t"
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#else
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"2: ldr %0, 3f \n\t"
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" ldr %0, [%0] \n\t"
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" b 1b \n\t"
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"3: .long __current \n\t"
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#endif
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" .previous \n\t"
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" .pushsection \".alt.smp.init\", \"a\" \n\t"
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" .long 0b - . \n\t"
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" b . + (2b - 0b) \n\t"
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" .popsection \n\t"
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#endif
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: "=r"(cur));
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#elif __LINUX_ARM_ARCH__>= 7 || \
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!defined(CONFIG_ARM_HAS_GROUP_RELOCS) || \
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(defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS))
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cur = __current;
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#else
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asm(LOAD_SYM_ARMV6(%0, __current) : "=r"(cur));
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#endif
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return cur;
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}
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#define current get_current()
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#endif /* __ASSEMBLY__ */
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#endif /* _ASM_ARM_CURRENT_H */
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