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de979c8357
With CONFIG_PREEMPTION disabled, arch/x86/entry/thunk_$(BITS).o becomes
an empty object file.
With some old versions of binutils (i.e., 2.35.90.20210113-1ubuntu1) the
GNU assembler doesn't generate a symbol table for empty object files and
objtool fails with the following error when a valid symbol table cannot
be found:
arch/x86/entry/thunk_64.o: warning: objtool: missing symbol table
To prevent this from happening, build thunk_$(BITS).o only if
CONFIG_PREEMPTION is enabled.
BugLink: https://bugs.launchpad.net/bugs/1911359
Fixes: 320100a5ff ("x86/entry: Remove the TRACE_IRQS cruft")
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/Ys/Ke7EWjcX+ZlXO@arighi-desktop
53 lines
1.1 KiB
ArmAsm
53 lines
1.1 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Save registers before calling assembly functions. This avoids
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* disturbance of register allocation in some inline assembly constructs.
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* Copyright 2001,2002 by Andi Kleen, SuSE Labs.
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*/
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#include <linux/linkage.h>
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#include "calling.h"
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#include <asm/asm.h>
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#include <asm/export.h>
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/* rdi: arg1 ... normal C conventions. rax is saved/restored. */
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.macro THUNK name, func
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SYM_FUNC_START_NOALIGN(\name)
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pushq %rbp
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movq %rsp, %rbp
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pushq %rdi
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pushq %rsi
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pushq %rdx
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pushq %rcx
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pushq %rax
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pushq %r8
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pushq %r9
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pushq %r10
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pushq %r11
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call \func
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jmp __thunk_restore
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SYM_FUNC_END(\name)
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_ASM_NOKPROBE(\name)
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.endm
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THUNK preempt_schedule_thunk, preempt_schedule
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THUNK preempt_schedule_notrace_thunk, preempt_schedule_notrace
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EXPORT_SYMBOL(preempt_schedule_thunk)
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EXPORT_SYMBOL(preempt_schedule_notrace_thunk)
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SYM_CODE_START_LOCAL_NOALIGN(__thunk_restore)
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popq %r11
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popq %r10
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popq %r9
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popq %r8
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popq %rax
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popq %rcx
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popq %rdx
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popq %rsi
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popq %rdi
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popq %rbp
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RET
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_ASM_NOKPROBE(__thunk_restore)
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SYM_CODE_END(__thunk_restore)
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