9142be9e64
The direct-call syscall dispatch function doesn't know that the exit()
and exit_group() syscall handlers don't return, so the call sites aren't
optimized accordingly.
Fix that by marking the exit syscall declarations __noreturn.
Fixes the following warnings:
vmlinux.o: warning: objtool: x64_sys_call+0x2804: __x64_sys_exit() is missing a __noreturn annotation
vmlinux.o: warning: objtool: ia32_sys_call+0x29b6: __ia32_sys_exit_group() is missing a __noreturn annotation
Fixes: 1e3ad78334 ("x86/syscall: Don't force use of indirect calls for system calls")
Closes: https://lkml.kernel.org/lkml/6dba9b32-db2c-4e6d-9500-7a08852f17a3@paulmck-laptop
Reported-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/5d8882bc077d8eadcc7fd1740b56dfb781f12288.1719381528.git.jpoimboe@kernel.org
37 lines
1.0 KiB
C
37 lines
1.0 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* System call table for UML/x86-64, copied from arch/x86/kernel/syscall_*.c
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* with some changes for UML.
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*/
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#include <linux/linkage.h>
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#include <linux/sys.h>
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#include <linux/cache.h>
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#include <asm/syscall.h>
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extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long,
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unsigned long, unsigned long,
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unsigned long, unsigned long);
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/*
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* Below you can see, in terms of #define's, the differences between the x86-64
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* and the UML syscall table.
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*/
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/* Not going to be implemented by UML, since we have no hardware. */
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#define sys_iopl sys_ni_syscall
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#define sys_ioperm sys_ni_syscall
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#define __SYSCALL_NORETURN __SYSCALL
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#define __SYSCALL(nr, sym) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
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#include <asm/syscalls_64.h>
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#undef __SYSCALL
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#define __SYSCALL(nr, sym) sym,
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const sys_call_ptr_t sys_call_table[] ____cacheline_aligned = {
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#include <asm/syscalls_64.h>
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};
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int syscall_table_size = sizeof(sys_call_table);
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