[ARM] Fix timer damage from d3d74453c34f8fd87674a8cf5b8a327c68f22e99

Move the xtime write mode seqlock into timer_tick(), so it only
surrounds the call to do_timer().

This avoids a deadlock in update_process_times() ...
hrtimer_get_softirq_time() which tries to get a read mode seqlock
on xtime, thereby preventing booting.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

21 files changed, 2 insertions, 71 deletions

diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c
index e59b5b84168d..b5867eca1d0b 100644
--- a/arch/arm/kernel/time.c
+++ b/arch/arm/kernel/time.c
@@ -325,7 +325,9 @@ void timer_tick(void)
         profile_tick(CPU_PROFILING);
         do_leds();
         do_set_rtc();
+        write_seqlock(&xtime_lock);
         do_timer(1);
+        write_sequnlock(&xtime_lock);
 #ifndef CONFIG_SMP
         update_process_times(user_mode(get_irq_regs()));
 #endif
diff --git a/arch/arm/mach-aaec2000/core.c b/arch/arm/mach-aaec2000/core.c
index 0446ef2f5bd6..b016be2b0e35 100644
--- a/arch/arm/mach-aaec2000/core.c
+++ b/arch/arm/mach-aaec2000/core.c
@@ -130,13 +130,9 @@ static irqreturn_t
 aaec2000_timer_interrupt(int irq, void *dev_id)
 {
         /* TODO: Check timer accuracy */
-        write_seqlock(&xtime_lock);
-
         timer_tick();
         TIMER1_CLEAR = 1;
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-clps711x/time.c b/arch/arm/mach-clps711x/time.c
index f428af7545b4..e5dc33f1f95c 100644
--- a/arch/arm/mach-clps711x/time.c
+++ b/arch/arm/mach-clps711x/time.c
@@ -50,9 +50,7 @@ static unsigned long clps711x_gettimeoffset(void)
 static irqreturn_t
 p720t_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
         timer_tick();
-        write_sequnlock(&xtime_lock);
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-clps7500/core.c b/arch/arm/mach-clps7500/core.c
index 986205ec9269..2ac63671ea5f 100644
--- a/arch/arm/mach-clps7500/core.c
+++ b/arch/arm/mach-clps7500/core.c
@@ -298,8 +298,6 @@ extern unsigned long ioc_timer_gettimeoffset(void);
 static irqreturn_t
 clps7500_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
-
         timer_tick();
 
         /* Why not using do_leds interface?? */
@@ -313,8 +311,6 @@ clps7500_timer_interrupt(int irq, void *dev_id)
                 }
         }
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-ebsa110/core.c b/arch/arm/mach-ebsa110/core.c
index 8c1b5690dfe8..7710e14b5268 100644
--- a/arch/arm/mach-ebsa110/core.c
+++ b/arch/arm/mach-ebsa110/core.c
@@ -178,8 +178,6 @@ ebsa110_timer_interrupt(int irq, void *dev_id)
 {
         u32 count;
 
-        write_seqlock(&xtime_lock);
-
         /* latch and read timer 1 */
         __raw_writeb(0x40, PIT_CTRL);
         count = __raw_readb(PIT_T1);
@@ -192,8 +190,6 @@ ebsa110_timer_interrupt(int irq, void *dev_id)
 
         timer_tick();
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-ep93xx/core.c b/arch/arm/mach-ep93xx/core.c
index 70b2c7801110..f1074ff02fdb 100644
--- a/arch/arm/mach-ep93xx/core.c
+++ b/arch/arm/mach-ep93xx/core.c
@@ -99,8 +99,6 @@ static unsigned int last_jiffy_time;
 
 static int ep93xx_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
-
         __raw_writel(1, EP93XX_TIMER1_CLEAR);
         while ((signed long)
                 (__raw_readl(EP93XX_TIMER4_VALUE_LOW) - last_jiffy_time)
@@ -109,8 +107,6 @@ static int ep93xx_timer_interrupt(int irq, void *dev_id)
                 timer_tick();
         }
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-footbridge/dc21285-timer.c b/arch/arm/mach-footbridge/dc21285-timer.c
index 3a63941d43be..b2a21189dd81 100644
--- a/arch/arm/mach-footbridge/dc21285-timer.c
+++ b/arch/arm/mach-footbridge/dc21285-timer.c
@@ -30,14 +30,10 @@ static unsigned long timer1_gettimeoffset (void)
 static irqreturn_t
 timer1_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
-
         *CSR_TIMER1_CLR = 0;
 
         timer_tick();
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-footbridge/isa-timer.c b/arch/arm/mach-footbridge/isa-timer.c
index d08d64139d00..a764e01d3573 100644
--- a/arch/arm/mach-footbridge/isa-timer.c
+++ b/arch/arm/mach-footbridge/isa-timer.c
@@ -64,9 +64,7 @@ static unsigned long isa_gettimeoffset(void)
 static irqreturn_t
 isa_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
         timer_tick();
-        write_sequnlock(&xtime_lock);
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-h720x/cpu-h7201.c b/arch/arm/mach-h720x/cpu-h7201.c
index 9107b8e2ad6e..c2a431f482f0 100644
--- a/arch/arm/mach-h720x/cpu-h7201.c
+++ b/arch/arm/mach-h720x/cpu-h7201.c
@@ -29,13 +29,9 @@
 static irqreturn_t
 h7201_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
-
         CPU_REG (TIMER_VIRT, TIMER_TOPSTAT);
         timer_tick();
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-h720x/cpu-h7202.c b/arch/arm/mach-h720x/cpu-h7202.c
index 0a1a25fb8ba8..c627fa124eb3 100644
--- a/arch/arm/mach-h720x/cpu-h7202.c
+++ b/arch/arm/mach-h720x/cpu-h7202.c
@@ -113,9 +113,7 @@ h7202_timerx_demux_handler(unsigned int irq_unused, struct irq_desc *desc)
         mask = CPU_REG (TIMER_VIRT, TIMER_TOPSTAT);
 
         if ( mask & TSTAT_T0INT ) {
-                write_seqlock(&xtime_lock);
                 timer_tick();
-                write_sequnlock(&xtime_lock);
                 if( mask == TSTAT_T0INT )
                         return;
         }
diff --git a/arch/arm/mach-integrator/core.c b/arch/arm/mach-integrator/core.c
index e9c82deb791d..7fbbc17f8e8b 100644
--- a/arch/arm/mach-integrator/core.c
+++ b/arch/arm/mach-integrator/core.c
@@ -250,8 +250,6 @@ unsigned long integrator_gettimeoffset(void)
 static irqreturn_t
 integrator_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
-
         /*
          * clear the interrupt
          */
@@ -259,8 +257,6 @@ integrator_timer_interrupt(int irq, void *dev_id)
 
         timer_tick();
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-ixp2000/core.c b/arch/arm/mach-ixp2000/core.c
index cb6ad211887a..81cdc8267206 100644
--- a/arch/arm/mach-ixp2000/core.c
+++ b/arch/arm/mach-ixp2000/core.c
@@ -206,8 +206,6 @@ unsigned long ixp2000_gettimeoffset (void)
 
 static int ixp2000_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
-
         /* clear timer 1 */
         ixp2000_reg_wrb(IXP2000_T1_CLR, 1);
 
@@ -217,8 +215,6 @@ static int ixp2000_timer_interrupt(int irq, void *dev_id)
                 next_jiffy_time -= ticks_per_jiffy;
         }
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-ks8695/time.c b/arch/arm/mach-ks8695/time.c
index d2c86e4a72eb..02f766b3121d 100644
--- a/arch/arm/mach-ks8695/time.c
+++ b/arch/arm/mach-ks8695/time.c
@@ -70,10 +70,7 @@ static unsigned long ks8695_gettimeoffset (void)
  */
 static irqreturn_t ks8695_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
         timer_tick();
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-lh7a40x/time.c b/arch/arm/mach-lh7a40x/time.c
index c25316d02537..e50e60b33851 100644
--- a/arch/arm/mach-lh7a40x/time.c
+++ b/arch/arm/mach-lh7a40x/time.c
@@ -41,13 +41,9 @@
 static irqreturn_t
 lh7a40x_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
-
         TIMER_EOI = 0;
         timer_tick();
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-mx3/time.c b/arch/arm/mach-mx3/time.c
index e81fb5c5d7c3..fb565c98dbfb 100644
--- a/arch/arm/mach-mx3/time.c
+++ b/arch/arm/mach-mx3/time.c
@@ -45,8 +45,6 @@ static irqreturn_t mxc_timer_interrupt(int irq, void *dev_id)
 {
         unsigned int next_match;
 
-        write_seqlock(&xtime_lock);
-
         if (__raw_readl(MXC_GPT_GPTSR) & GPTSR_OF1) {
                 do {
                         timer_tick();
@@ -57,8 +55,6 @@ static irqreturn_t mxc_timer_interrupt(int irq, void *dev_id)
                                        __raw_readl(MXC_GPT_GPTCNT)) <= 0);
         }
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-netx/time.c b/arch/arm/mach-netx/time.c
index 4762e207b0bf..ea07b54afa59 100644
--- a/arch/arm/mach-netx/time.c
+++ b/arch/arm/mach-netx/time.c
@@ -33,12 +33,8 @@
 static irqreturn_t
 netx_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
-
         timer_tick();
 
-        write_sequnlock(&xtime_lock);
-
         /* acknowledge interrupt */
         writel(COUNTER_BIT(0), NETX_GPIO_IRQ);
 
diff --git a/arch/arm/mach-omap2/timer-gp.c b/arch/arm/mach-omap2/timer-gp.c
index 8d322c20ccae..3234deedb946 100644
--- a/arch/arm/mach-omap2/timer-gp.c
+++ b/arch/arm/mach-omap2/timer-gp.c
@@ -40,13 +40,9 @@ static inline void omap2_gp_timer_start(unsigned long load_val)
 
 static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
-
         omap_dm_timer_write_status(gptimer, OMAP_TIMER_INT_OVERFLOW);
         timer_tick();
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-pnx4008/time.c b/arch/arm/mach-pnx4008/time.c
index 67e05f005a6b..6d4ca8fc0cb4 100644
--- a/arch/arm/mach-pnx4008/time.c
+++ b/arch/arm/mach-pnx4008/time.c
@@ -51,8 +51,6 @@ static irqreturn_t pnx4008_timer_interrupt(int irq, void *dev_id)
 {
         if (__raw_readl(HSTIM_INT) & MATCH0_INT) {
 
-                write_seqlock(&xtime_lock);
-
                 do {
                         timer_tick();
 
@@ -73,8 +71,6 @@ static irqreturn_t pnx4008_timer_interrupt(int irq, void *dev_id)
                 } while ((signed)
                          (__raw_readl(HSTIM_MATCH0) -
                           __raw_readl(HSTIM_COUNTER)) < 0);
-
-                write_sequnlock(&xtime_lock);
         }
 
         return IRQ_HANDLED;
diff --git a/arch/arm/mach-realview/core.c b/arch/arm/mach-realview/core.c
index c7f1b44da40d..61d70218f1e8 100644
--- a/arch/arm/mach-realview/core.c
+++ b/arch/arm/mach-realview/core.c
@@ -530,8 +530,6 @@ static unsigned long realview_gettimeoffset(void)
  */
 static irqreturn_t realview_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
-
         // ...clear the interrupt
         writel(1, TIMER0_VA_BASE + TIMER_INTCLR);
 
@@ -542,8 +540,6 @@ static irqreturn_t realview_timer_interrupt(int irq, void *dev_id)
         update_process_times(user_mode(get_irq_regs()));
 #endif
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-sa1100/time.c b/arch/arm/mach-sa1100/time.c
index fdf7b016e7ad..47f8640438e6 100644
--- a/arch/arm/mach-sa1100/time.c
+++ b/arch/arm/mach-sa1100/time.c
@@ -62,8 +62,6 @@ sa1100_timer_interrupt(int irq, void *dev_id)
 {
         unsigned int next_match;
 
-        write_seqlock(&xtime_lock);
-
 #ifdef CONFIG_NO_IDLE_HZ
         if (match_posponed) {
                 match_posponed = 0;
@@ -85,8 +83,6 @@ sa1100_timer_interrupt(int irq, void *dev_id)
                 next_match = (OSMR0 += LATCH);
         } while ((signed long)(next_match - OSCR) <= 0);
 
-        write_sequnlock(&xtime_lock);
-
         return IRQ_HANDLED;
 }
 
diff --git a/arch/arm/mach-shark/core.c b/arch/arm/mach-shark/core.c
index a0545db2a34f..09d9f33d4072 100644
--- a/arch/arm/mach-shark/core.c
+++ b/arch/arm/mach-shark/core.c
@@ -82,9 +82,7 @@ static void __init shark_map_io(void)
 static irqreturn_t
 shark_timer_interrupt(int irq, void *dev_id)
 {
-        write_seqlock(&xtime_lock);
         timer_tick();
-        write_sequnlock(&xtime_lock);
         return IRQ_HANDLED;
 }