Merge tag 'timers-core-2022-12-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer updates from Thomas Gleixner:
 "Updates for timers, timekeeping and drivers:

  Core:

   - The timer_shutdown[_sync]() infrastructure:

     Tearing down timers can be tedious when there are circular
     dependencies to other things which need to be torn down. A prime
     example is timer and workqueue where the timer schedules work and
     the work arms the timer.

     What needs to prevented is that pending work which is drained via
     destroy_workqueue() does not rearm the previously shutdown timer.
     Nothing in that shutdown sequence relies on the timer being
     functional.

     The conclusion was that the semantics of timer_shutdown_sync()
     should be:
	- timer is not enqueued
    	- timer callback is not running
    	- timer cannot be rearmed

     Preventing the rearming of shutdown timers is done by discarding
     rearm attempts silently.

     A warning for the case that a rearm attempt of a shutdown timer is
     detected would not be really helpful because it's entirely unclear
     how it should be acted upon. The only way to address such a case is
     to add 'if (in_shutdown)' conditionals all over the place. This is
     error prone and in most cases of teardown not required all.

   - The real fix for the bluetooth HCI teardown based on
     timer_shutdown_sync().

     A larger scale conversion to timer_shutdown_sync() is work in
     progress.

   - Consolidation of VDSO time namespace helper functions

   - Small fixes for timer and timerqueue

  Drivers:

   - Prevent integer overflow on the XGene-1 TVAL register which causes
     an never ending interrupt storm.

   - The usual set of new device tree bindings

   - Small fixes and improvements all over the place"

* tag 'timers-core-2022-12-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
  dt-bindings: timer: renesas,cmt: Add r8a779g0 CMT support
  dt-bindings: timer: renesas,tmu: Add r8a779g0 support
  clocksource/drivers/arm_arch_timer: Use kstrtobool() instead of strtobool()
  clocksource/drivers/timer-ti-dm: Fix missing clk_disable_unprepare in dmtimer_systimer_init_clock()
  clocksource/drivers/timer-ti-dm: Clear settings on probe and free
  clocksource/drivers/timer-ti-dm: Make timer_get_irq static
  clocksource/drivers/timer-ti-dm: Fix warning for omap_timer_match
  clocksource/drivers/arm_arch_timer: Fix XGene-1 TVAL register math error
  clocksource/drivers/timer-npcm7xx: Enable timer 1 clock before use
  dt-bindings: timer: nuvoton,npcm7xx-timer: Allow specifying all clocks
  dt-bindings: timer: rockchip: Add rockchip,rk3128-timer
  clockevents: Repair kernel-doc for clockevent_delta2ns()
  clocksource/drivers/ingenic-ost: Define pm functions properly in platform_driver struct
  clocksource/drivers/sh_cmt: Access registers according to spec
  vdso/timens: Refactor copy-pasted find_timens_vvar_page() helper into one copy
  Bluetooth: hci_qca: Fix the teardown problem for real
  timers: Update the documentation to reflect on the new timer_shutdown() API
  timers: Provide timer_shutdown[_sync]()
  timers: Add shutdown mechanism to the internal functions
  timers: Split [try_to_]del_timer[_sync]() to prepare for shutdown mode
  ...

Documentation/RCU/Design/Requirements/Requirements.rst

@@ -1858,7 +1858,7 @@ unloaded. After a given module has been unloaded, any attempt to call
 one of its functions results in a segmentation fault. The module-unload
 functions must therefore cancel any delayed calls to loadable-module
 functions, for example, any outstanding mod_timer() must be dealt
-with via del_timer_sync() or similar.
+with via timer_shutdown_sync() or similar.
 
 Unfortunately, there is no way to cancel an RCU callback; once you
 invoke call_rcu(), the callback function is eventually going to be

Documentation/core-api/local_ops.rst

@@ -191,7 +191,7 @@ Here is a sample module which implements a basic per cpu counter using
 
     static void __exit test_exit(void)
     {
-            del_timer_sync(&test_timer);
+            timer_shutdown_sync(&test_timer);
     }
 
     module_init(test_init);

Documentation/devicetree/bindings/timer/nuvoton,npcm7xx-timer.yaml

@@ -25,7 +25,13 @@ properties:
       - description: The timer interrupt of timer 0
 
   clocks:
-    maxItems: 1
+    items:
+      - description: The reference clock for timer 0
+      - description: The reference clock for timer 1
+      - description: The reference clock for timer 2
+      - description: The reference clock for timer 3
+      - description: The reference clock for timer 4
+    minItems: 1
 
 required:
   - compatible

Documentation/devicetree/bindings/timer/renesas,cmt.yaml

@@ -102,12 +102,14 @@ properties:
           - enum:
               - renesas,r8a779a0-cmt0     # 32-bit CMT0 on R-Car V3U
               - renesas,r8a779f0-cmt0     # 32-bit CMT0 on R-Car S4-8
+              - renesas,r8a779g0-cmt0     # 32-bit CMT0 on R-Car V4H
           - const: renesas,rcar-gen4-cmt0 # 32-bit CMT0 on R-Car Gen4
 
       - items:
           - enum:
               - renesas,r8a779a0-cmt1     # 48-bit CMT on R-Car V3U
               - renesas,r8a779f0-cmt1     # 48-bit CMT on R-Car S4-8
+              - renesas,r8a779g0-cmt1     # 48-bit CMT on R-Car V4H
           - const: renesas,rcar-gen4-cmt1 # 48-bit CMT on R-Car Gen4
 
   reg:

Documentation/devicetree/bindings/timer/renesas,tmu.yaml

@@ -38,6 +38,7 @@ properties:
           - renesas,tmu-r8a77995 # R-Car D3
           - renesas,tmu-r8a779a0 # R-Car V3U
           - renesas,tmu-r8a779f0 # R-Car S4-8
+          - renesas,tmu-r8a779g0 # R-Car V4H
       - const: renesas,tmu
 
   reg:

Documentation/devicetree/bindings/timer/rockchip,rk-timer.yaml

@@ -18,6 +18,7 @@ properties:
           - enum:
               - rockchip,rv1108-timer
               - rockchip,rk3036-timer
+              - rockchip,rk3128-timer
               - rockchip,rk3188-timer
               - rockchip,rk3228-timer
               - rockchip,rk3229-timer

Documentation/kernel-hacking/locking.rst

@@ -967,7 +967,7 @@ you might do the following::
 
             while (list) {
                     struct foo *next = list->next;
-                    del_timer(&list->timer);
+                    timer_delete(&list->timer);
                     kfree(list);
                     list = next;
             }
@@ -981,7 +981,7 @@ the lock after we spin_unlock_bh(), and then try to free
 the element (which has already been freed!).
 
 This can be avoided by checking the result of
-del_timer(): if it returns 1, the timer has been deleted.
+timer_delete(): if it returns 1, the timer has been deleted.
 If 0, it means (in this case) that it is currently running, so we can
 do::
 
@@ -990,7 +990,7 @@ do::
 
                     while (list) {
                             struct foo *next = list->next;
-                            if (!del_timer(&list->timer)) {
+                            if (!timer_delete(&list->timer)) {
                                     /* Give timer a chance to delete this */
                                     spin_unlock_bh(&list_lock);
                                     goto retry;
@@ -1005,9 +1005,12 @@ do::
 Another common problem is deleting timers which restart themselves (by
 calling add_timer() at the end of their timer function).
 Because this is a fairly common case which is prone to races, you should
-use del_timer_sync() (``include/linux/timer.h``) to
-handle this case. It returns the number of times the timer had to be
-deleted before we finally stopped it from adding itself back in.
+use timer_delete_sync() (``include/linux/timer.h``) to handle this case.
+
+Before freeing a timer, timer_shutdown() or timer_shutdown_sync() should be
+called which will keep it from being rearmed. Any subsequent attempt to
+rearm the timer will be silently ignored by the core code.
+
 
 Locking Speed
 =============
@@ -1335,7 +1338,7 @@ lock.
 
 -  kfree()
 
--  add_timer() and del_timer()
+-  add_timer() and timer_delete()
 
 Mutex API reference
 ===================

Documentation/timers/hrtimers.rst

@@ -118,7 +118,7 @@ existing timer wheel code, as it is mature and well suited. Sharing code
 was not really a win, due to the different data structures. Also, the
 hrtimer functions now have clearer behavior and clearer names - such as
 hrtimer_try_to_cancel() and hrtimer_cancel() [which are roughly
-equivalent to del_timer() and del_timer_sync()] - so there's no direct
+equivalent to timer_delete() and timer_delete_sync()] - so there's no direct
 1:1 mapping between them on the algorithmic level, and thus no real
 potential for code sharing either.
 

Documentation/translations/it_IT/kernel-hacking/locking.rst

@@ -990,7 +990,7 @@ potreste fare come segue::
 
             while (list) {
                     struct foo *next = list->next;
-                    del_timer(&list->timer);
+                    timer_delete(&list->timer);
                     kfree(list);
                     list = next;
             }
@@ -1003,7 +1003,7 @@ e prenderà il *lock* solo dopo spin_unlock_bh(), e cercherà
 di eliminare il suo oggetto (che però è già stato eliminato).
 
 Questo può essere evitato controllando il valore di ritorno di
-del_timer(): se ritorna 1, il temporizzatore è stato già
+timer_delete(): se ritorna 1, il temporizzatore è stato già
 rimosso. Se 0, significa (in questo caso) che il temporizzatore è in
 esecuzione, quindi possiamo fare come segue::
 
@@ -1012,7 +1012,7 @@ esecuzione, quindi possiamo fare come segue::
 
                     while (list) {
                             struct foo *next = list->next;
-                            if (!del_timer(&list->timer)) {
+                            if (!timer_delete(&list->timer)) {
                                     /* Give timer a chance to delete this */
                                     spin_unlock_bh(&list_lock);
                                     goto retry;
@@ -1026,10 +1026,8 @@ esecuzione, quindi possiamo fare come segue::
 Un altro problema è l'eliminazione dei temporizzatori che si riavviano
 da soli (chiamando add_timer() alla fine della loro esecuzione).
 Dato che questo è un problema abbastanza comune con una propensione
-alle corse critiche, dovreste usare del_timer_sync()
-(``include/linux/timer.h``) per gestire questo caso. Questa ritorna il
-numero di volte che il temporizzatore è stato interrotto prima che
-fosse in grado di fermarlo senza che si riavviasse.
+alle corse critiche, dovreste usare timer_delete_sync()
+(``include/linux/timer.h``) per gestire questo caso.
 
 Velocità della sincronizzazione
 ===============================
@@ -1374,7 +1372,7 @@ contesto, o trattenendo un qualsiasi *lock*.
 
 -  kfree()
 
--  add_timer() e del_timer()
+-  add_timer() e timer_delete()
 
 Riferimento per l'API dei Mutex
 ===============================

Documentation/translations/zh_CN/core-api/local_ops.rst

@@ -185,7 +185,7 @@ UP之间没有不同的行为，在你的架构的 ``local.h`` 中包括 ``asm-g
 
     static void __exit test_exit(void)
     {
-            del_timer_sync(&test_timer);
+            timer_shutdown_sync(&test_timer);
     }
 
     module_init(test_init);

arch/arm/mach-spear/time.c

@@ -90,7 +90,7 @@ static void __init spear_clocksource_init(void)
 		200, 16, clocksource_mmio_readw_up);
 }
 
-static inline void timer_shutdown(struct clock_event_device *evt)
+static inline void spear_timer_shutdown(struct clock_event_device *evt)
 {
 	u16 val = readw(gpt_base + CR(CLKEVT));
 
@@ -101,7 +101,7 @@ static inline void timer_shutdown(struct clock_event_device *evt)
 
 static int spear_shutdown(struct clock_event_device *evt)
 {
-	timer_shutdown(evt);
+	spear_timer_shutdown(evt);
 
 	return 0;
 }
@@ -111,7 +111,7 @@ static int spear_set_oneshot(struct clock_event_device *evt)
 	u16 val;
 
 	/* stop the timer */
-	timer_shutdown(evt);
+	spear_timer_shutdown(evt);
 
 	val = readw(gpt_base + CR(CLKEVT));
 	val |= CTRL_ONE_SHOT;
@@ -126,7 +126,7 @@ static int spear_set_periodic(struct clock_event_device *evt)
 	u16 val;
 
 	/* stop the timer */
-	timer_shutdown(evt);
+	spear_timer_shutdown(evt);
 
 	period = clk_get_rate(gpt_clk) / HZ;
 	period >>= CTRL_PRESCALER16;

arch/arm64/kernel/vdso.c

@@ -151,28 +151,6 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
 	mmap_read_unlock(mm);
 	return 0;
 }
-
-static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
-{
-	if (likely(vma->vm_mm == current->mm))
-		return current->nsproxy->time_ns->vvar_page;
-
-	/*
-	 * VM_PFNMAP | VM_IO protect .fault() handler from being called
-	 * through interfaces like /proc/$pid/mem or
-	 * process_vm_{readv,writev}() as long as there's no .access()
-	 * in special_mapping_vmops.
-	 * For more details check_vma_flags() and __access_remote_vm()
-	 */
-	WARN(1, "vvar_page accessed remotely");
-
-	return NULL;
-}
-#else
-static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
-{
-	return NULL;
-}
 #endif
 
 static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,

arch/powerpc/kernel/vdso.c

@@ -129,28 +129,6 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
 
 	return 0;
 }
-
-static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
-{
-	if (likely(vma->vm_mm == current->mm))
-		return current->nsproxy->time_ns->vvar_page;
-
-	/*
-	 * VM_PFNMAP | VM_IO protect .fault() handler from being called
-	 * through interfaces like /proc/$pid/mem or
-	 * process_vm_{readv,writev}() as long as there's no .access()
-	 * in special_mapping_vmops.
-	 * For more details check_vma_flags() and __access_remote_vm()
-	 */
-	WARN(1, "vvar_page accessed remotely");
-
-	return NULL;
-}
-#else
-static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
-{
-	return NULL;
-}
 #endif
 
 static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,

arch/riscv/kernel/vdso.c

@@ -137,28 +137,6 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
 	mmap_read_unlock(mm);
 	return 0;
 }
-
-static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
-{
-	if (likely(vma->vm_mm == current->mm))
-		return current->nsproxy->time_ns->vvar_page;
-
-	/*
-	 * VM_PFNMAP | VM_IO protect .fault() handler from being called
-	 * through interfaces like /proc/$pid/mem or
-	 * process_vm_{readv,writev}() as long as there's no .access()
-	 * in special_mapping_vmops.
-	 * For more details check_vma_flags() and __access_remote_vm()
-	 */
-	WARN(1, "vvar_page accessed remotely");
-
-	return NULL;
-}
-#else
-static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
-{
-	return NULL;
-}
 #endif
 
 static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,

arch/s390/kernel/vdso.c

@@ -44,21 +44,6 @@ struct vdso_data *arch_get_vdso_data(void *vvar_page)
 	return (struct vdso_data *)(vvar_page);
 }
 
-static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
-{
-	if (likely(vma->vm_mm == current->mm))
-		return current->nsproxy->time_ns->vvar_page;
-	/*
-	 * VM_PFNMAP | VM_IO protect .fault() handler from being called
-	 * through interfaces like /proc/$pid/mem or
-	 * process_vm_{readv,writev}() as long as there's no .access()
-	 * in special_mapping_vmops().
-	 * For more details check_vma_flags() and __access_remote_vm()
-	 */
-	WARN(1, "vvar_page accessed remotely");
-	return NULL;
-}
-
 /*
  * The VVAR page layout depends on whether a task belongs to the root or
  * non-root time namespace. Whenever a task changes its namespace, the VVAR
@@ -84,11 +69,6 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
 	mmap_read_unlock(mm);
 	return 0;
 }
-#else
-static inline struct page *find_timens_vvar_page(struct vm_area_struct *vma)
-{
-	return NULL;
-}
 #endif
 
 static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,

arch/x86/entry/vdso/vma.c

@@ -98,24 +98,6 @@ static int vdso_mremap(const struct vm_special_mapping *sm,
 }
 
 #ifdef CONFIG_TIME_NS
-static struct page *find_timens_vvar_page(struct vm_area_struct *vma)
-{
-	if (likely(vma->vm_mm == current->mm))
-		return current->nsproxy->time_ns->vvar_page;
-
-	/*
-	 * VM_PFNMAP | VM_IO protect .fault() handler from being called
-	 * through interfaces like /proc/$pid/mem or
-	 * process_vm_{readv,writev}() as long as there's no .access()
-	 * in special_mapping_vmops().
-	 * For more details check_vma_flags() and __access_remote_vm()
-	 */
-
-	WARN(1, "vvar_page accessed remotely");
-
-	return NULL;
-}
-
 /*
  * The vvar page layout depends on whether a task belongs to the root or
  * non-root time namespace. Whenever a task changes its namespace, the VVAR
@@ -140,11 +122,6 @@ int vdso_join_timens(struct task_struct *task, struct time_namespace *ns)
 
 	return 0;
 }
-#else
-static inline struct page *find_timens_vvar_page(struct vm_area_struct *vma)
-{
-	return NULL;
-}
 #endif
 
 static vm_fault_t vvar_fault(const struct vm_special_mapping *sm,

drivers/bluetooth/hci_qca.c

@@ -696,9 +696,15 @@ static int qca_close(struct hci_uart *hu)
 	skb_queue_purge(&qca->tx_wait_q);
 	skb_queue_purge(&qca->txq);
 	skb_queue_purge(&qca->rx_memdump_q);
+	/*
+	 * Shut the timers down so they can't be rearmed when
+	 * destroy_workqueue() drains pending work which in turn might try
+	 * to arm a timer.  After shutdown rearm attempts are silently
+	 * ignored by the timer core code.
+	 */
+	timer_shutdown_sync(&qca->tx_idle_timer);
+	timer_shutdown_sync(&qca->wake_retrans_timer);
 	destroy_workqueue(qca->workqueue);
-	del_timer_sync(&qca->tx_idle_timer);
-	del_timer_sync(&qca->wake_retrans_timer);
 	qca->hu = NULL;
 
 	kfree_skb(qca->rx_skb);

drivers/char/tpm/tpm-dev-common.c

@@ -155,7 +155,7 @@ ssize_t tpm_common_read(struct file *file, char __user *buf,
 out:
 	if (!priv->response_length) {
 		*off = 0;
-		del_singleshot_timer_sync(&priv->user_read_timer);
+		del_timer_sync(&priv->user_read_timer);
 		flush_work(&priv->timeout_work);
 	}
 	mutex_unlock(&priv->buffer_mutex);
@@ -262,7 +262,7 @@ __poll_t tpm_common_poll(struct file *file, poll_table *wait)
 void tpm_common_release(struct file *file, struct file_priv *priv)
 {
 	flush_work(&priv->async_work);
-	del_singleshot_timer_sync(&priv->user_read_timer);
+	del_timer_sync(&priv->user_read_timer);
 	flush_work(&priv->timeout_work);
 	file->private_data = NULL;
 	priv->response_length = 0;

drivers/clocksource/arm_arch_timer.c

@@ -18,6 +18,7 @@
 #include <linux/clocksource.h>
 #include <linux/clocksource_ids.h>
 #include <linux/interrupt.h>
+#include <linux/kstrtox.h>
 #include <linux/of_irq.h>
 #include <linux/of_address.h>
 #include <linux/io.h>
@@ -97,7 +98,7 @@ static bool evtstrm_enable __ro_after_init = IS_ENABLED(CONFIG_ARM_ARCH_TIMER_EV
 
 static int __init early_evtstrm_cfg(char *buf)
 {
-	return strtobool(buf, &evtstrm_enable);
+	return kstrtobool(buf, &evtstrm_enable);
 }
 early_param("clocksource.arm_arch_timer.evtstrm", early_evtstrm_cfg);
 
@@ -687,8 +688,8 @@ static irqreturn_t arch_timer_handler_virt_mem(int irq, void *dev_id)
 	return timer_handler(ARCH_TIMER_MEM_VIRT_ACCESS, evt);
 }
 
-static __always_inline int timer_shutdown(const int access,
-					  struct clock_event_device *clk)
+static __always_inline int arch_timer_shutdown(const int access,
+					       struct clock_event_device *clk)
 {
 	unsigned long ctrl;
 
@@ -701,22 +702,22 @@ static __always_inline int timer_shutdown(const int access,
 
 static int arch_timer_shutdown_virt(struct clock_event_device *clk)
 {
-	return timer_shutdown(ARCH_TIMER_VIRT_ACCESS, clk);
+	return arch_timer_shutdown(ARCH_TIMER_VIRT_ACCESS, clk);
 }
 
 static int arch_timer_shutdown_phys(struct clock_event_device *clk)
 {
-	return timer_shutdown(ARCH_TIMER_PHYS_ACCESS, clk);
+	return arch_timer_shutdown(ARCH_TIMER_PHYS_ACCESS, clk);
 }
 
 static int arch_timer_shutdown_virt_mem(struct clock_event_device *clk)
 {
-	return timer_shutdown(ARCH_TIMER_MEM_VIRT_ACCESS, clk);
+	return arch_timer_shutdown(ARCH_TIMER_MEM_VIRT_ACCESS, clk);
 }
 
 static int arch_timer_shutdown_phys_mem(struct clock_event_device *clk)
 {
-	return timer_shutdown(ARCH_TIMER_MEM_PHYS_ACCESS, clk);
+	return arch_timer_shutdown(ARCH_TIMER_MEM_PHYS_ACCESS, clk);
 }
 
 static __always_inline void set_next_event(const int access, unsigned long evt,

drivers/clocksource/ingenic-ost.c

@@ -141,7 +141,7 @@ static int __init ingenic_ost_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static int __maybe_unused ingenic_ost_suspend(struct device *dev)
+static int ingenic_ost_suspend(struct device *dev)
 {
 	struct ingenic_ost *ost = dev_get_drvdata(dev);
 
@@ -150,14 +150,14 @@ static int __maybe_unused ingenic_ost_suspend(struct device *dev)
 	return 0;
 }
 
-static int __maybe_unused ingenic_ost_resume(struct device *dev)
+static int ingenic_ost_resume(struct device *dev)
 {
 	struct ingenic_ost *ost = dev_get_drvdata(dev);
 
 	return clk_enable(ost->clk);
 }
 
-static const struct dev_pm_ops __maybe_unused ingenic_ost_pm_ops = {
+static const struct dev_pm_ops ingenic_ost_pm_ops = {
 	/* _noirq: We want the OST clock to be gated last / ungated first */
 	.suspend_noirq = ingenic_ost_suspend,
 	.resume_noirq  = ingenic_ost_resume,
@@ -181,9 +181,7 @@ static const struct of_device_id ingenic_ost_of_match[] = {
 static struct platform_driver ingenic_ost_driver = {
 	.driver = {
 		.name = "ingenic-ost",
-#ifdef CONFIG_PM_SUSPEND
-		.pm = &ingenic_ost_pm_ops,
-#endif
+		.pm = pm_sleep_ptr(&ingenic_ost_pm_ops),
 		.of_match_table = ingenic_ost_of_match,
 	},
 };

drivers/clocksource/sh_cmt.c

@@ -13,6 +13,7 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
 #include <linux/ioport.h>
 #include <linux/irq.h>
 #include <linux/module.h>
@@ -116,6 +117,7 @@ struct sh_cmt_device {
 	void __iomem *mapbase;
 	struct clk *clk;
 	unsigned long rate;
+	unsigned int reg_delay;
 
 	raw_spinlock_t lock; /* Protect the shared start/stop register */
 
@@ -247,10 +249,17 @@ static inline u32 sh_cmt_read_cmstr(struct sh_cmt_channel *ch)
 
 static inline void sh_cmt_write_cmstr(struct sh_cmt_channel *ch, u32 value)
 {
-	if (ch->iostart)
-		ch->cmt->info->write_control(ch->iostart, 0, value);
-	else
-		ch->cmt->info->write_control(ch->cmt->mapbase, 0, value);
+	u32 old_value = sh_cmt_read_cmstr(ch);
+
+	if (value != old_value) {
+		if (ch->iostart) {
+			ch->cmt->info->write_control(ch->iostart, 0, value);
+			udelay(ch->cmt->reg_delay);
+		} else {
+			ch->cmt->info->write_control(ch->cmt->mapbase, 0, value);
+			udelay(ch->cmt->reg_delay);
+		}
+	}
 }
 
 static inline u32 sh_cmt_read_cmcsr(struct sh_cmt_channel *ch)
@@ -260,7 +269,12 @@ static inline u32 sh_cmt_read_cmcsr(struct sh_cmt_channel *ch)
 
 static inline void sh_cmt_write_cmcsr(struct sh_cmt_channel *ch, u32 value)
 {
-	ch->cmt->info->write_control(ch->ioctrl, CMCSR, value);
+	u32 old_value = sh_cmt_read_cmcsr(ch);
+
+	if (value != old_value) {
+		ch->cmt->info->write_control(ch->ioctrl, CMCSR, value);
+		udelay(ch->cmt->reg_delay);
+	}
 }
 
 static inline u32 sh_cmt_read_cmcnt(struct sh_cmt_channel *ch)
@@ -268,14 +282,33 @@ static inline u32 sh_cmt_read_cmcnt(struct sh_cmt_channel *ch)
 	return ch->cmt->info->read_count(ch->ioctrl, CMCNT);
 }
 
-static inline void sh_cmt_write_cmcnt(struct sh_cmt_channel *ch, u32 value)
+static inline int sh_cmt_write_cmcnt(struct sh_cmt_channel *ch, u32 value)
 {
+	/* Tests showed that we need to wait 3 clocks here */
+	unsigned int cmcnt_delay = DIV_ROUND_UP(3 * ch->cmt->reg_delay, 2);
+	u32 reg;
+
+	if (ch->cmt->info->model > SH_CMT_16BIT) {
+		int ret = read_poll_timeout_atomic(sh_cmt_read_cmcsr, reg,
+						   !(reg & SH_CMT32_CMCSR_WRFLG),
+						   1, cmcnt_delay, false, ch);
+		if (ret < 0)
+			return ret;
+	}
+
 	ch->cmt->info->write_count(ch->ioctrl, CMCNT, value);
+	udelay(cmcnt_delay);
+	return 0;
 }
 
 static inline void sh_cmt_write_cmcor(struct sh_cmt_channel *ch, u32 value)
 {
-	ch->cmt->info->write_count(ch->ioctrl, CMCOR, value);
+	u32 old_value = ch->cmt->info->read_count(ch->ioctrl, CMCOR);
+
+	if (value != old_value) {
+		ch->cmt->info->write_count(ch->ioctrl, CMCOR, value);
+		udelay(ch->cmt->reg_delay);
+	}
 }
 
 static u32 sh_cmt_get_counter(struct sh_cmt_channel *ch, u32 *has_wrapped)
@@ -319,7 +352,7 @@ static void sh_cmt_start_stop_ch(struct sh_cmt_channel *ch, int start)
 
 static int sh_cmt_enable(struct sh_cmt_channel *ch)
 {
-	int k, ret;
+	int ret;
 
 	dev_pm_syscore_device(&ch->cmt->pdev->dev, true);
 
@@ -347,26 +380,9 @@ static int sh_cmt_enable(struct sh_cmt_channel *ch)
 	}
 
 	sh_cmt_write_cmcor(ch, 0xffffffff);
-	sh_cmt_write_cmcnt(ch, 0);
-
-	/*
-	 * According to the sh73a0 user's manual, as CMCNT can be operated
-	 * only by the RCLK (Pseudo 32 kHz), there's one restriction on
-	 * modifying CMCNT register; two RCLK cycles are necessary before
-	 * this register is either read or any modification of the value
-	 * it holds is reflected in the LSI's actual operation.
-	 *
-	 * While at it, we're supposed to clear out the CMCNT as of this
-	 * moment, so make sure it's processed properly here.  This will
-	 * take RCLKx2 at maximum.
-	 */
-	for (k = 0; k < 100; k++) {
-		if (!sh_cmt_read_cmcnt(ch))
-			break;
-		udelay(1);
-	}
+	ret = sh_cmt_write_cmcnt(ch, 0);
 
-	if (sh_cmt_read_cmcnt(ch)) {
+	if (ret || sh_cmt_read_cmcnt(ch)) {
 		dev_err(&ch->cmt->pdev->dev, "ch%u: cannot clear CMCNT\n",
 			ch->index);
 		ret = -ETIMEDOUT;
@@ -995,8 +1011,8 @@ MODULE_DEVICE_TABLE(of, sh_cmt_of_table);
 
 static int sh_cmt_setup(struct sh_cmt_device *cmt, struct platform_device *pdev)
 {
-	unsigned int mask;
-	unsigned int i;
+	unsigned int mask, i;
+	unsigned long rate;
 	int ret;
 
 	cmt->pdev = pdev;
@@ -1032,10 +1048,16 @@ static int sh_cmt_setup(struct sh_cmt_device *cmt, struct platform_device *pdev)
 	if (ret < 0)
 		goto err_clk_unprepare;
 
-	if (cmt->info->width == 16)
-		cmt->rate = clk_get_rate(cmt->clk) / 512;
-	else
-		cmt->rate = clk_get_rate(cmt->clk) / 8;
+	rate = clk_get_rate(cmt->clk);
+	if (!rate) {
+		ret = -EINVAL;
+		goto err_clk_disable;
+	}
+
+	/* We shall wait 2 input clks after register writes */
+	if (cmt->info->model >= SH_CMT_48BIT)
+		cmt->reg_delay = DIV_ROUND_UP(2UL * USEC_PER_SEC, rate);
+	cmt->rate = rate / (cmt->info->width == 16 ? 512 : 8);
 
 	/* Map the memory resource(s). */
 	ret = sh_cmt_map_memory(cmt);

drivers/clocksource/timer-npcm7xx.c

@@ -188,6 +188,7 @@ static void __init npcm7xx_clocksource_init(void)
 
 static int __init npcm7xx_timer_init(struct device_node *np)
 {
+	struct clk *clk;
 	int ret;
 
 	ret = timer_of_init(np, &npcm7xx_to);
@@ -199,6 +200,15 @@ static int __init npcm7xx_timer_init(struct device_node *np)
 	npcm7xx_to.of_clk.rate = npcm7xx_to.of_clk.rate /
 		(NPCM7XX_Tx_MIN_PRESCALE + 1);
 
+	/* Enable the clock for timer1, if it exists */
+	clk = of_clk_get(np, 1);
+	if (clk) {
+		if (!IS_ERR(clk))
+			clk_prepare_enable(clk);
+		else
+			pr_warn("%pOF: Failed to get clock for timer1: %pe", np, clk);
+	}
+
 	npcm7xx_clocksource_init();
 	npcm7xx_clockevents_init();
 

drivers/clocksource/timer-sp804.c

@@ -155,14 +155,14 @@ static irqreturn_t sp804_timer_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static inline void timer_shutdown(struct clock_event_device *evt)
+static inline void evt_timer_shutdown(struct clock_event_device *evt)
 {
 	writel(0, common_clkevt->ctrl);
 }
 
 static int sp804_shutdown(struct clock_event_device *evt)
 {
-	timer_shutdown(evt);
+	evt_timer_shutdown(evt);
 	return 0;
 }
 
@@ -171,7 +171,7 @@ static int sp804_set_periodic(struct clock_event_device *evt)
 	unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
 			     TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
 
-	timer_shutdown(evt);
+	evt_timer_shutdown(evt);
 	writel(common_clkevt->reload, common_clkevt->load);
 	writel(ctrl, common_clkevt->ctrl);
 	return 0;

drivers/clocksource/timer-ti-dm-systimer.c

@@ -345,8 +345,10 @@ static int __init dmtimer_systimer_init_clock(struct dmtimer_systimer *t,
 		return error;
 
 	r = clk_get_rate(clock);
-	if (!r)
+	if (!r) {
+		clk_disable_unprepare(clock);
 		return -ENODEV;
+	}
 
 	if (is_ick)
 		t->ick = clock;

drivers/clocksource/timer-ti-dm.c

@@ -633,6 +633,8 @@ static struct omap_dm_timer *omap_dm_timer_request_by_node(struct device_node *n
 static int omap_dm_timer_free(struct omap_dm_timer *cookie)
 {
 	struct dmtimer *timer;
+	struct device *dev;
+	int rc;
 
 	timer = to_dmtimer(cookie);
 	if (unlikely(!timer))
@@ -640,10 +642,21 @@ static int omap_dm_timer_free(struct omap_dm_timer *cookie)
 
 	WARN_ON(!timer->reserved);
 	timer->reserved = 0;
+
+	dev = &timer->pdev->dev;
+	rc = pm_runtime_resume_and_get(dev);
+	if (rc)
+		return rc;
+
+	/* Clear timer configuration */
+	dmtimer_write(timer, OMAP_TIMER_CTRL_REG, 0);
+
+	pm_runtime_put_sync(dev);
+
 	return 0;
 }
 
-int omap_dm_timer_get_irq(struct omap_dm_timer *cookie)
+static int omap_dm_timer_get_irq(struct omap_dm_timer *cookie)
 {
 	struct dmtimer *timer = to_dmtimer(cookie);
 	if (timer)
@@ -1135,6 +1148,10 @@ static int omap_dm_timer_probe(struct platform_device *pdev)
 			goto err_disable;
 		}
 		__omap_dm_timer_init_regs(timer);
+
+		/* Clear timer configuration */
+		dmtimer_write(timer, OMAP_TIMER_CTRL_REG, 0);
+
 		pm_runtime_put(dev);
 	}
 
@@ -1258,7 +1275,7 @@ static struct platform_driver omap_dm_timer_driver = {
 	.remove = omap_dm_timer_remove,
 	.driver = {
 		.name   = "omap_timer",
-		.of_match_table = of_match_ptr(omap_timer_match),
+		.of_match_table = omap_timer_match,
 		.pm = &omap_dm_timer_pm_ops,
 	},
 };

drivers/staging/wlan-ng/hfa384x_usb.c

@@ -1116,8 +1116,8 @@ static int hfa384x_usbctlx_complete_sync(struct hfa384x *hw,
 		if (ctlx == get_active_ctlx(hw)) {
 			spin_unlock_irqrestore(&hw->ctlxq.lock, flags);
 
-			del_singleshot_timer_sync(&hw->reqtimer);
-			del_singleshot_timer_sync(&hw->resptimer);
+			del_timer_sync(&hw->reqtimer);
+			del_timer_sync(&hw->resptimer);
 			hw->req_timer_done = 1;
 			hw->resp_timer_done = 1;
 			usb_kill_urb(&hw->ctlx_urb);

drivers/staging/wlan-ng/prism2usb.c

@@ -170,9 +170,9 @@ static void prism2sta_disconnect_usb(struct usb_interface *interface)
 		 */
 		prism2sta_ifstate(wlandev, P80211ENUM_ifstate_disable);
 
-		del_singleshot_timer_sync(&hw->throttle);
-		del_singleshot_timer_sync(&hw->reqtimer);
-		del_singleshot_timer_sync(&hw->resptimer);
+		del_timer_sync(&hw->throttle);
+		del_timer_sync(&hw->reqtimer);
+		del_timer_sync(&hw->resptimer);
 
 		/* Unlink all the URBs. This "removes the wheels"
 		 * from the entire CTLX handling mechanism.

include/clocksource/timer-ti-dm.h

@@ -62,8 +62,6 @@
 struct omap_dm_timer {
 };
 
-int omap_dm_timer_get_irq(struct omap_dm_timer *timer);
-
 u32 omap_dm_timer_modify_idlect_mask(u32 inputmask);
 
 /*

include/linux/time_namespace.h

@@ -45,6 +45,7 @@ struct time_namespace *copy_time_ns(unsigned long flags,
 void free_time_ns(struct time_namespace *ns);
 void timens_on_fork(struct nsproxy *nsproxy, struct task_struct *tsk);
 struct vdso_data *arch_get_vdso_data(void *vvar_page);
+struct page *find_timens_vvar_page(struct vm_area_struct *vma);
 
 static inline void put_time_ns(struct time_namespace *ns)
 {
@@ -141,6 +142,11 @@ static inline void timens_on_fork(struct nsproxy *nsproxy,
 	return;
 }
 
+static inline struct page *find_timens_vvar_page(struct vm_area_struct *vma)
+{
+	return NULL;
+}
+
 static inline void timens_add_monotonic(struct timespec64 *ts) { }
 static inline void timens_add_boottime(struct timespec64 *ts) { }
 

include/linux/timer.h

@@ -169,7 +169,6 @@ static inline int timer_pending(const struct timer_list * timer)
 }
 
 extern void add_timer_on(struct timer_list *timer, int cpu);
-extern int del_timer(struct timer_list * timer);
 extern int mod_timer(struct timer_list *timer, unsigned long expires);
 extern int mod_timer_pending(struct timer_list *timer, unsigned long expires);
 extern int timer_reduce(struct timer_list *timer, unsigned long expires);
@@ -183,14 +182,36 @@ extern int timer_reduce(struct timer_list *timer, unsigned long expires);
 extern void add_timer(struct timer_list *timer);
 
 extern int try_to_del_timer_sync(struct timer_list *timer);
+extern int timer_delete_sync(struct timer_list *timer);
+extern int timer_delete(struct timer_list *timer);
+extern int timer_shutdown_sync(struct timer_list *timer);
+extern int timer_shutdown(struct timer_list *timer);
 
-#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
-  extern int del_timer_sync(struct timer_list *timer);
-#else
-# define del_timer_sync(t)		del_timer(t)
-#endif
+/**
+ * del_timer_sync - Delete a pending timer and wait for a running callback
+ * @timer:	The timer to be deleted
+ *
+ * See timer_delete_sync() for detailed explanation.
+ *
+ * Do not use in new code. Use timer_delete_sync() instead.
+ */
+static inline int del_timer_sync(struct timer_list *timer)
+{
+	return timer_delete_sync(timer);
+}
 
-#define del_singleshot_timer_sync(t) del_timer_sync(t)
+/**
+ * del_timer - Delete a pending timer
+ * @timer:	The timer to be deleted
+ *
+ * See timer_delete() for detailed explanation.
+ *
+ * Do not use in new code. Use timer_delete() instead.
+ */
+static inline int del_timer(struct timer_list *timer)
+{
+	return timer_delete(timer);
+}
 
 extern void init_timers(void);
 struct hrtimer;

include/linux/timerqueue.h

@@ -35,7 +35,7 @@ struct timerqueue_node *timerqueue_getnext(struct timerqueue_head *head)
 {
 	struct rb_node *leftmost = rb_first_cached(&head->rb_root);
 
-	return rb_entry(leftmost, struct timerqueue_node, node);
+	return rb_entry_safe(leftmost, struct timerqueue_node, node);
 }
 
 static inline void timerqueue_init(struct timerqueue_node *node)

kernel/time/clockevents.c

@@ -76,7 +76,7 @@ static u64 cev_delta2ns(unsigned long latch, struct clock_event_device *evt,
 }
 
 /**
- * clockevents_delta2ns - Convert a latch value (device ticks) to nanoseconds
+ * clockevent_delta2ns - Convert a latch value (device ticks) to nanoseconds
  * @latch:	value to convert
  * @evt:	pointer to clock event device descriptor
  *

kernel/time/namespace.c

@@ -192,6 +192,24 @@ static void timens_setup_vdso_data(struct vdso_data *vdata,
 	offset[CLOCK_BOOTTIME_ALARM]	= boottime;
 }
 
+struct page *find_timens_vvar_page(struct vm_area_struct *vma)
+{
+	if (likely(vma->vm_mm == current->mm))
+		return current->nsproxy->time_ns->vvar_page;
+
+	/*
+	 * VM_PFNMAP | VM_IO protect .fault() handler from being called
+	 * through interfaces like /proc/$pid/mem or
+	 * process_vm_{readv,writev}() as long as there's no .access()
+	 * in special_mapping_vmops().
+	 * For more details check_vma_flags() and __access_remote_vm()
+	 */
+
+	WARN(1, "vvar_page accessed remotely");
+
+	return NULL;
+}
+
 /*
  * Protects possibly multiple offsets writers racing each other
  * and tasks entering the namespace.

net/sunrpc/xprt.c

@@ -1164,7 +1164,7 @@ xprt_request_enqueue_receive(struct rpc_task *task)
 	spin_unlock(&xprt->queue_lock);
 
 	/* Turn off autodisconnect */
-	del_singleshot_timer_sync(&xprt->timer);
+	del_timer_sync(&xprt->timer);
 	return 0;
 }