linux-kernel - [PATCH v2 3/5] entry: add enter_from_user

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20201201142755.31931-4-svens@linux.ibm.com>
Date:   Tue,  1 Dec 2020 15:27:53 +0100
From:   Sven Schnelle <svens@...ux.ibm.com>
To:     Thomas Gleixner <tglx@...utronix.de>
Cc:     linux-kernel@...r.kernel.org, Sven Schnelle <svens@...ux.ibm.com>
Subject: [PATCH v2 3/5] entry: add enter_from_user_mode() wrapper

Can be called from architecture dependent code, and simply
calls __enter_from_user_mode(). This way __enter_from_user_mode
can still be inlined because it is declared static.

Signed-off-by: Sven Schnelle <svens@...ux.ibm.com>
---
 include/linux/entry-common.h | 11 +++++++++++
 kernel/entry/common.c        | 15 +++++----------
 2 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h
index 474f29638d2c..28a8554fad7d 100644
--- a/include/linux/entry-common.h
+++ b/include/linux/entry-common.h
@@ -402,4 +402,15 @@ void irqentry_exit_cond_resched(void);
  */
 void noinstr irqentry_exit(struct pt_regs *regs, irqentry_state_t state);
 
+/**
+ * enter_from_user_mode - Establish state when coming from user mode
+ *
+ * Syscall/interrupt entry disables interrupts, but user mode is traced as
+ * interrupts enabled. Also with NO_HZ_FULL RCU might be idle.
+ *
+ * 1) Tell lockdep that interrupts are disabled
+ * 2) Invoke context tracking if enabled to reactivate RCU
+ * 3) Trace interrupts off state
+ */
+void enter_from_user_mode(struct pt_regs *regs);
 #endif
diff --git a/kernel/entry/common.c b/kernel/entry/common.c
index 076ee1cde67f..ee588ee9f122 100644
--- a/kernel/entry/common.c
+++ b/kernel/entry/common.c
@@ -8,16 +8,6 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/syscalls.h>
 
-/**
- * __enter_from_user_mode - Establish state when coming from user mode
- *
- * Syscall/interrupt entry disables interrupts, but user mode is traced as
- * interrupts enabled. Also with NO_HZ_FULL RCU might be idle.
- *
- * 1) Tell lockdep that interrupts are disabled
- * 2) Invoke context tracking if enabled to reactivate RCU
- * 3) Trace interrupts off state
- */
 static __always_inline void __enter_from_user_mode(struct pt_regs *regs)
 {
 	arch_check_user_regs(regs);
@@ -31,6 +21,11 @@ static __always_inline void __enter_from_user_mode(struct pt_regs *regs)
 	instrumentation_end();
 }
 
+void noinstr enter_from_user_mode(struct pt_regs *regs)
+{
+	__enter_from_user_mode(regs);
+}
+
 static inline void syscall_enter_audit(struct pt_regs *regs, long syscall)
 {
 	if (unlikely(audit_context())) {
-- 
2.17.1