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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
36 lines
829 B
ArmAsm
36 lines
829 B
ArmAsm
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Trampoline to trace irqs off. (otherwise CALLER_ADDR1 might crash)
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* Copyright 2008 by Steven Rostedt, Red Hat, Inc
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* (inspired by Andi Kleen's thunk_64.S)
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*/
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#include <linux/linkage.h>
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#include <asm/asm.h>
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#include <asm/export.h>
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/* put return address in eax (arg1) */
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.macro THUNK name, func, put_ret_addr_in_eax=0
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SYM_CODE_START_NOALIGN(\name)
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pushl %eax
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pushl %ecx
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pushl %edx
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.if \put_ret_addr_in_eax
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/* Place EIP in the arg1 */
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movl 3*4(%esp), %eax
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.endif
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call \func
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popl %edx
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popl %ecx
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popl %eax
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RET
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_ASM_NOKPROBE(\name)
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SYM_CODE_END(\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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