Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
entry: Remove syscall_enter_from_user_mode_prepare()
Open code the only user in the x86 syscall code and reduce the zoo of
functions.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://patch.msgid.link/20251027084306.652839989@linutronix.de
authored by
Thomas Gleixner
and committed by
Ingo Molnar
54a5ab56
5204be16
+7
-30
+2
-1
arch/x86/entry/syscall_32.c
+2
-1
arch/x86/entry/syscall_32.c
···
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* fetch EBP before invoking any of the syscall entry work
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* functions.
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*/
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-
syscall_enter_from_user_mode_prepare(regs);
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+
enter_from_user_mode(regs);
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instrumentation_begin();
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local_irq_enable();
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/* Fetch EBP from where the vDSO stashed it. */
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if (IS_ENABLED(CONFIG_X86_64)) {
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/*
+5
-21
include/linux/entry-common.h
+5
-21
include/linux/entry-common.h
···
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SYSCALL_WORK_SYSCALL_EXIT_TRAP | \
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ARCH_SYSCALL_WORK_EXIT)
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-
/**
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* syscall_enter_from_user_mode_prepare - Establish state and enable interrupts
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* @regs: Pointer to currents pt_regs
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*
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* Invoked from architecture specific syscall entry code with interrupts
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* disabled. The calling code has to be non-instrumentable. When the
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* function returns all state is correct, interrupts are enabled and the
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* subsequent functions can be instrumented.
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*
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* This handles lockdep, RCU (context tracking) and tracing state, i.e.
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* the functionality provided by enter_from_user_mode().
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*
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* This is invoked when there is extra architecture specific functionality
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* to be done between establishing state and handling user mode entry work.
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*/
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void syscall_enter_from_user_mode_prepare(struct pt_regs *regs);
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-
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long syscall_trace_enter(struct pt_regs *regs, long syscall, unsigned long work);
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/**
···
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* @syscall: The syscall number
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*
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* Invoked from architecture specific syscall entry code with interrupts
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* enabled after invoking syscall_enter_from_user_mode_prepare() and extra
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* architecture specific work.
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* enabled after invoking enter_from_user_mode(), enabling interrupts and
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* extra architecture specific work.
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*
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* Returns: The original or a modified syscall number
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*
···
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* function returns all state is correct, interrupts are enabled and the
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* subsequent functions can be instrumented.
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*
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* This is combination of syscall_enter_from_user_mode_prepare() and
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* syscall_enter_from_user_mode_work().
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* This is the combination of enter_from_user_mode() and
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* syscall_enter_from_user_mode_work() to be used when there is no
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* architecture specific work to be done between the two.
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*
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* Returns: The original or a modified syscall number. See
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* syscall_enter_from_user_mode_work() for further explanation.
-8
kernel/entry/syscall-common.c
-8
kernel/entry/syscall-common.c
···
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return ret ? : syscall;
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}
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noinstr void syscall_enter_from_user_mode_prepare(struct pt_regs *regs)
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{
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enter_from_user_mode(regs);
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instrumentation_begin();
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local_irq_enable();
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instrumentation_end();
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}
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-
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/*
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* If SYSCALL_EMU is set, then the only reason to report is when
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* SINGLESTEP is set (i.e. PTRACE_SYSEMU_SINGLESTEP). This syscall