Merge tag 'for-linus-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml

Pull UML updates from Richard Weinberger:

 - A new timer mode, time travel, for testing with UML

 - Many bugixes/improvements for the serial line driver

 - Various bugfixes

* tag 'for-linus-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: fix build without CONFIG_UML_TIME_TRAVEL_SUPPORT
  um: Fix kcov crash during startup
  um: configs: Remove useless UEVENT_HELPER_PATH
  um: Support time travel mode
  um: Pass nsecs to os timer functions
  um: Remove drivers/ssl.h
  um: Don't garbage collect in deactivate_all_fds()
  um: Silence lockdep complaint about mmap_sem
  um: Remove locking in deactivate_all_fds()
  um: Timer code cleanup
  um: fix os_timer_one_shot()
  um: Fix IRQ controller regression on console read

3 files changed, 53 insertions, 7 deletions

diff --git a/arch/um/include/asm/mmu_context.h b/arch/um/include/asm/mmu_context.h
index 9f4b4bb78120..00cefd33afdd 100644
--- a/arch/um/include/asm/mmu_context.h
+++ b/arch/um/include/asm/mmu_context.h
@@ -52,7 +52,7 @@ static inline void activate_mm(struct mm_struct *old, struct mm_struct *new)
          * when the new ->mm is used for the first time.
          */
         __switch_mm(&new->context.id);
-        down_write(&new->mmap_sem);
+        down_write_nested(&new->mmap_sem, 1);
         uml_setup_stubs(new);
         up_write(&new->mmap_sem);
 }
diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h
index ebf23012a59b..4a62ac4251a5 100644
--- a/arch/um/include/shared/os.h
+++ b/arch/um/include/shared/os.h
@@ -250,15 +250,13 @@ extern void os_warn(const char *fmt, ...)
 
 /* time.c */
 extern void os_idle_sleep(unsigned long long nsecs);
-extern int os_timer_create(void* timer);
-extern int os_timer_set_interval(void* timer, void* its);
-extern int os_timer_one_shot(int ticks);
-extern long long os_timer_disable(void);
-extern long os_timer_remain(void* timer);
+extern int os_timer_create(void);
+extern int os_timer_set_interval(unsigned long long nsecs);
+extern int os_timer_one_shot(unsigned long long nsecs);
+extern void os_timer_disable(void);
 extern void uml_idle_timer(void);
 extern long long os_persistent_clock_emulation(void);
 extern long long os_nsecs(void);
-extern long long os_vnsecs(void);
 
 /* skas/mem.c */
 extern long run_syscall_stub(struct mm_id * mm_idp,
diff --git a/arch/um/include/shared/timer-internal.h b/arch/um/include/shared/timer-internal.h
index 03e6f217f807..8574338bf23b 100644
--- a/arch/um/include/shared/timer-internal.h
+++ b/arch/um/include/shared/timer-internal.h
@@ -10,4 +10,52 @@
 #define TIMER_MULTIPLIER 256
 #define TIMER_MIN_DELTA  500
 
+enum time_travel_mode {
+        TT_MODE_OFF,
+        TT_MODE_BASIC,
+        TT_MODE_INFCPU,
+};
+
+enum time_travel_timer_mode {
+        TT_TMR_DISABLED,
+        TT_TMR_ONESHOT,
+        TT_TMR_PERIODIC,
+};
+
+#ifdef CONFIG_UML_TIME_TRAVEL_SUPPORT
+extern enum time_travel_mode time_travel_mode;
+extern unsigned long long time_travel_time;
+extern enum time_travel_timer_mode time_travel_timer_mode;
+extern unsigned long long time_travel_timer_expiry;
+extern unsigned long long time_travel_timer_interval;
+
+static inline void time_travel_set_time(unsigned long long ns)
+{
+        time_travel_time = ns;
+}
+
+static inline void time_travel_set_timer(enum time_travel_timer_mode mode,
+                                         unsigned long long expiry)
+{
+        time_travel_timer_mode = mode;
+        time_travel_timer_expiry = expiry;
+}
+#else
+#define time_travel_mode TT_MODE_OFF
+#define time_travel_time 0
+#define time_travel_timer_expiry 0
+#define time_travel_timer_interval 0
+
+static inline void time_travel_set_time(unsigned long long ns)
+{
+}
+
+static inline void time_travel_set_timer(enum time_travel_timer_mode mode,
+                                         unsigned long long expiry)
+{
+}
+
+#define time_travel_timer_mode TT_TMR_DISABLED
+#endif
+
 #endif