Merge tag 'core_urgent_for_v6.3_rc4' of git://git.kernel.org/pub/scm/linux/kernel...

Pull core fixes from Borislav Petkov:

 - Do the delayed RCU wakeup for kthreads in the proper order so that
   former doesn't get ignored

 - A noinstr warning fix

* tag 'core_urgent_for_v6.3_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  entry/rcu: Check TIF_RESCHED _after_ delayed RCU wake-up
  entry: Fix noinstr warning in __enter_from_user_mode()

diff --git a/include/linux/context_tracking.h b/include/linux/context_tracking.h
index d4afa85..3a7909e 100644 (file)
--- a/include/linux/context_tracking.h
+++ b/include/linux/context_tracking.h
@@ -96,6 +96,7 @@ static inline void user_exit_irqoff(void) { }
 static inline int exception_enter(void) { return 0; }
 static inline void exception_exit(enum ctx_state prev_ctx) { }
 static inline int ct_state(void) { return -1; }
+static inline int __ct_state(void) { return -1; }
 static __always_inline bool context_tracking_guest_enter(void) { return false; }
 static inline void context_tracking_guest_exit(void) { }
 #define CT_WARN_ON(cond) do { } while (0)

diff --git a/include/linux/context_tracking_state.h b/include/linux/context_tracking_state.h
index 4a4d56f..fdd537e 100644 (file)
--- a/include/linux/context_tracking_state.h
+++ b/include/linux/context_tracking_state.h
@@ -46,7 +46,9 @@ struct context_tracking {
 
 #ifdef CONFIG_CONTEXT_TRACKING
 DECLARE_PER_CPU(struct context_tracking, context_tracking);
+#endif
 
+#ifdef CONFIG_CONTEXT_TRACKING_USER
 static __always_inline int __ct_state(void)
 {
        return arch_atomic_read(this_cpu_ptr(&context_tracking.state)) & CT_STATE_MASK;

diff --git a/kernel/entry/common.c b/kernel/entry/common.c
index 846add8..be61332 100644 (file)
--- a/kernel/entry/common.c
+++ b/kernel/entry/common.c
@@ -21,7 +21,7 @@ static __always_inline void __enter_from_user_mode(struct pt_regs *regs)
        arch_enter_from_user_mode(regs);
        lockdep_hardirqs_off(CALLER_ADDR0);
 
-       CT_WARN_ON(ct_state() != CONTEXT_USER);
+       CT_WARN_ON(__ct_state() != CONTEXT_USER);
        user_exit_irqoff();
 
        instrumentation_begin();
@@ -192,13 +192,14 @@ static unsigned long exit_to_user_mode_loop(struct pt_regs *regs,
 
 static void exit_to_user_mode_prepare(struct pt_regs *regs)
 {
-       unsigned long ti_work = read_thread_flags();
+       unsigned long ti_work;
 
        lockdep_assert_irqs_disabled();
 
        /* Flush pending rcuog wakeup before the last need_resched() check */
        tick_nohz_user_enter_prepare();
 
+       ti_work = read_thread_flags();
        if (unlikely(ti_work & EXIT_TO_USER_MODE_WORK))
                ti_work = exit_to_user_mode_loop(regs, ti_work);