linux-kernel - [PATCH v11 09/14] entry: Rework syscall_exit_to_user_mode

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Message-ID: <20260128031934.3906955-10-ruanjinjie@huawei.com>
Date: Wed, 28 Jan 2026 11:19:29 +0800
From: Jinjie Ruan <ruanjinjie@...wei.com>
To: <catalin.marinas@....com>, <will@...nel.org>, <oleg@...hat.com>,
	<tglx@...utronix.de>, <peterz@...radead.org>, <luto@...nel.org>,
	<shuah@...nel.org>, <kees@...nel.org>, <wad@...omium.org>,
	<kevin.brodsky@....com>, <deller@....de>, <akpm@...ux-foundation.org>,
	<charlie@...osinc.com>, <ldv@...ace.io>, <mark.rutland@....com>,
	<anshuman.khandual@....com>, <song@...nel.org>, <ryan.roberts@....com>,
	<thuth@...hat.com>, <ada.coupriediaz@....com>, <broonie@...nel.org>,
	<pengcan@...inos.cn>, <liqiang01@...inos.cn>, <kmal@...k.li>,
	<dvyukov@...gle.com>, <reddybalavignesh9979@...il.com>,
	<richard.weiyang@...il.com>, <linux-arm-kernel@...ts.infradead.org>,
	<linux-kernel@...r.kernel.org>, <linux-kselftest@...r.kernel.org>
CC: <ruanjinjie@...wei.com>
Subject: [PATCH v11 09/14] entry: Rework syscall_exit_to_user_mode_work() for arch reuse

In the generic entry code, the beginning of
syscall_exit_to_user_mode_work() can be reused on arm64 so it makes
sense to rework it.

In preparation for moving arm64 over to the generic entry
code, as nothing calls syscall_exit_to_user_mode_work() except for
syscall_exit_to_user_mode(), move local_irq_disable_exit_to_user() and
syscall_exit_to_user_mode_prepare() out from
syscall_exit_to_user_mode_work() to the only one caller.

Also update the comment and no functional changes.

Reviewed-by: Kevin Brodsky <kevin.brodsky@....com>
Reviewed-by: Thomas Gleixner <tglx@...utronix.de>
Signed-off-by: Jinjie Ruan <ruanjinjie@...wei.com>
---
 include/linux/entry-common.h | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h
index e4a8287af822..c4fea642d931 100644
--- a/include/linux/entry-common.h
+++ b/include/linux/entry-common.h
@@ -125,14 +125,14 @@ void syscall_exit_work(struct pt_regs *regs, unsigned long work);
  * syscall_exit_to_user_mode_work - Handle work before returning to user mode
  * @regs:	Pointer to currents pt_regs
  *
- * Same as step 1 and 2 of syscall_exit_to_user_mode() but without calling
+ * Same as step 1 of syscall_exit_to_user_mode() but without calling
+ * local_irq_disable(), syscall_exit_to_user_mode_prepare() and
  * exit_to_user_mode() to perform the final transition to user mode.
  *
- * Calling convention is the same as for syscall_exit_to_user_mode() and it
- * returns with all work handled and interrupts disabled. The caller must
- * invoke exit_to_user_mode() before actually switching to user mode to
- * make the final state transitions. Interrupts must stay disabled between
- * return from this function and the invocation of exit_to_user_mode().
+ * Calling convention is the same as for syscall_exit_to_user_mode(). The
+ * caller must invoke local_irq_disable(), __exit_to_user_mode_prepare() and
+ * exit_to_user_mode() before actually switching to user mode to
+ * make the final state transitions.
  */
 static __always_inline void syscall_exit_to_user_mode_work(struct pt_regs *regs)
 {
@@ -155,8 +155,6 @@ static __always_inline void syscall_exit_to_user_mode_work(struct pt_regs *regs)
 	 */
 	if (unlikely(work & SYSCALL_WORK_EXIT))
 		syscall_exit_work(regs, work);
-	local_irq_disable_exit_to_user();
-	syscall_exit_to_user_mode_prepare(regs);
 }
 
 /**
@@ -192,6 +190,8 @@ static __always_inline void syscall_exit_to_user_mode(struct pt_regs *regs)
 {
 	instrumentation_begin();
 	syscall_exit_to_user_mode_work(regs);
+	local_irq_disable_exit_to_user();
+	syscall_exit_to_user_mode_prepare(regs);
 	instrumentation_end();
 	exit_to_user_mode();
 }
-- 
2.34.1