diff options
| author | Mark Rutland <mark.rutland@arm.com> | 2026-04-07 14:16:42 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@kernel.org> | 2026-04-08 11:43:31 +0200 |
| commit | 22f66e7ef4ce9414b4bd18abe50ead4a1284b01a (patch) | |
| tree | cb348ba7286723ee38584e83dc92dd97cad3d306 /kernel | |
| parent | 1f0d117cd6ca8e74e70e415e89b059fce37674c6 (diff) | |
entry: Remove local_irq_{enable,disable}_exit_to_user()
local_irq_enable_exit_to_user() and local_irq_disable_exit_to_user() are
never overridden by architecture code, and are always equivalent to
local_irq_enable() and local_irq_disable().
These functions were added on the assumption that arm64 would override
them to manage 'DAIF' exception masking, as described by Thomas Gleixner
in these threads:
https://lore.kernel.org/all/20190919150809.340471236@linutronix.de/
https://lore.kernel.org/all/alpine.DEB.2.21.1910240119090.1852@nanos.tec.linutronix.de/
In practice arm64 did not need to override either. Prior to moving to
the generic irqentry code, arm64's management of DAIF was reworked in
commit:
97d935faacde ("arm64: Unmask Debug + SError in do_notify_resume()")
Since that commit, arm64 only masks interrupts during the 'prepare' step
when returning to user mode, and masks other DAIF exceptions later.
Within arm64_exit_to_user_mode(), the arm64 entry code is as follows:
local_irq_disable();
exit_to_user_mode_prepare_legacy(regs);
local_daif_mask();
mte_check_tfsr_exit();
exit_to_user_mode();
Remove the unnecessary local_irq_enable_exit_to_user() and
local_irq_disable_exit_to_user() functions.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Reviewed-by: Jinjie Ruan <ruanjinjie@huawei.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260407131650.3813777-3-mark.rutland@arm.com
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/entry/common.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/entry/common.c b/kernel/entry/common.c index 9ef63e414791..b5e05d87ba39 100644 --- a/kernel/entry/common.c +++ b/kernel/entry/common.c @@ -47,7 +47,7 @@ static __always_inline unsigned long __exit_to_user_mode_loop(struct pt_regs *re */ while (ti_work & EXIT_TO_USER_MODE_WORK_LOOP) { - local_irq_enable_exit_to_user(ti_work); + local_irq_enable(); if (ti_work & (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY)) { if (!rseq_grant_slice_extension(ti_work & TIF_SLICE_EXT_DENY)) @@ -74,7 +74,7 @@ static __always_inline unsigned long __exit_to_user_mode_loop(struct pt_regs *re * might have changed while interrupts and preemption was * enabled above. */ - local_irq_disable_exit_to_user(); + local_irq_disable(); /* Check if any of the above work has queued a deferred wakeup */ tick_nohz_user_enter_prepare(); |