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entry: Remove syscall_enter_from_user_mode()

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All architecture use either:

    nr = syscall_enter_from_user_mode_randomize_stack(regs, nr);

or

    enter_from_user_mode_randomize_stack(regs);
    nr = syscall_enter_from_user_mode_work(regs, nr);

Remove the now unused function.

Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Tested-by: Mukesh Kumar Chaurasiya (IBM) <mkchauras@gmail.com>
Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com>
Reviewed-by: Mukesh Kumar Chaurasiya (IBM) <mkchauras@gmail.com>
Link: https://patch.msgid.link/20260707190254.132654198@kernel.org
This commit is contained in:
Thomas Gleixner
2026-07-12 12:38:01 +02:00
parent 9d311796e2
commit bad2a27ba8
3 changed files with 17 additions and 46 deletions
Download Patch File Download Diff File Expand all files Collapse all files
Documentation/core-api/entry.rst
+10 -7
View File
@@ -68,7 +68,7 @@ invoked from low-level assembly code looks like this:
noinstr void syscall(struct pt_regs *regs, int nr)
{
arch_syscall_enter(regs);
nr = syscall_enter_from_user_mode(regs, nr);
nr = syscall_enter_from_user_mode_randomize_stack(regs, nr);
instrumentation_begin();
if (!invoke_syscall(regs, nr) && nr != -1)
@@ -78,12 +78,14 @@ invoked from low-level assembly code looks like this:
syscall_exit_to_user_mode(regs);
}
syscall_enter_from_user_mode() first invokes enter_from_user_mode() which
establishes state in the following order:
syscall_enter_from_user_mode_randomize_stack() first invokes
enter_from_user_mode_randomize_stack() which establishes state in the
following order:
* Lockdep
* RCU / Context tracking
* Tracing
* Apply stack randomization
and then invokes the various entry work functions like ptrace, seccomp, audit,
syscall tracing, etc. After all that is done, the instrumentable invoke_syscall
@@ -99,10 +101,11 @@ transition in the reverse order:
* RCU / Context tracking
* Lockdep
syscall_enter_from_user_mode() and syscall_exit_to_user_mode() are also
available as fine grained subfunctions in cases where the architecture code
has to do extra work between the various steps. In such cases it has to
ensure that enter_from_user_mode() is called first on entry and
syscall_enter_from_user_mode_randomize_stack() and
syscall_exit_to_user_mode() are also available as fine grained subfunctions
in cases where the architecture code has to do extra work between the
various steps. In such cases it has to ensure that
enter_from_user_mode_randomize_stack() is called first on entry and
exit_to_user_mode() is called last on exit.
Do not nest syscalls. Nested syscalls will cause RCU and/or context tracking
include/linux/entry-common.h
+4 -36
View File
@@ -20,7 +20,7 @@
#endif
/*
* SYSCALL_WORK flags handled in syscall_enter_from_user_mode()
* SYSCALL_WORK flags handled in syscall_enter_from_user_mode_work()
*/
#define SYSCALL_WORK_ENTER (SYSCALL_WORK_SECCOMP | \
SYSCALL_WORK_SYSCALL_TRACEPOINT | \
@@ -205,42 +205,10 @@ do { \
_ret; \
})
/**
* syscall_enter_from_user_mode - Establish state and check and handle work
* before invoking a syscall
* @regs: Pointer to currents pt_regs
* @syscall: The syscall number
*
* Invoked from architecture specific syscall entry code with interrupts
* disabled. The calling code has to be non-instrumentable. When the
* function returns all state is correct, interrupts are enabled and the
* subsequent functions can be instrumented.
*
* This is the combination of enter_from_user_mode() and
* syscall_enter_from_user_mode_work() to be used when there is no
* architecture specific work to be done between the two.
*
* Returns: The original or a modified syscall number. See
* syscall_enter_from_user_mode_work() for further explanation.
*/
static __always_inline long syscall_enter_from_user_mode(struct pt_regs *regs, long syscall)
{
long ret;
enter_from_user_mode(regs);
instrumentation_begin();
local_irq_enable();
ret = syscall_enter_from_user_mode_work(regs, syscall);
instrumentation_end();
return ret;
}
/*
* If SYSCALL_EMU is set, then the only reason to report is when
* SINGLESTEP is set (i.e. PTRACE_SYSEMU_SINGLESTEP). This syscall
* instruction has been already reported in syscall_enter_from_user_mode().
* If SYSCALL_EMU is set, then the only reason to report is when SINGLESTEP is
* set (i.e. PTRACE_SYSEMU_SINGLESTEP). This syscall instruction has been
* already reported in syscall_enter_from_user_mode_work().
*/
static __always_inline bool report_single_step(unsigned long work)
{
include/linux/irq-entry-common.h
+3 -3
View File
@@ -49,9 +49,9 @@
* Defaults to an empty implementation. Can be replaced by architecture
* specific code.
*
* Invoked from syscall_enter_from_user_mode() in the non-instrumentable
* section. Use __always_inline so the compiler cannot push it out of line
* and make it instrumentable.
* Invoked from enter_from_user_mode() in the non-instrumentable section. Use
* __always_inline so the compiler cannot push it out of line and make it
* instrumentable.
*/
static __always_inline void arch_enter_from_user_mode(struct pt_regs *regs);