Re: Suspend-resume failure on Intel Eagle Lake Core2Duo

[Tomi Sarvela]

On 28/07/17 00:08, Thomas Gleixner wrote:
On Thu, 27 Jul 2017, Thomas Gleixner wrote:
On Thu, 27 Jul 2017, Thomas Gleixner wrote:
On Thu, 27 Jul 2017, Tomi Sarvela wrote:
On 27/07/17 10:42, Thomas Gleixner wrote:
On Thu, 27 Jul 2017, Tomi Sarvela wrote:
On 26/07/17 17:26, Thomas Gleixner wrote:
So reverting that commit does not help. Does it help on your machine?

Yes. Reverting it does not cause the machine to lock up on resume.

I haven't tested if the machine locks up later on, but at least it
survives
couple of s/r cycles.

Can you please try to add 'nohpet' to the kernel command line?

Option nohpet didn't change anything, still hangs on s/r.

Ok. Was a shot in the dark. I tried on a similar machine, but that one
resumes fine (except that the AHCI controller plays silly buggers, but
nothing interrupt related). I might have access to another core2duo machine
tomorrow.

I'll send you a debug patch shortly, but can you please first check when
the wreckage happens by testing the states in

     /sys/power/pm_test

freezer
devices
platform
processors
core

Actually for suspend to ram we only have

         freezer, devices, platform

I assume it's platform because that is where the actual interrupt
suspend/resume happens.

If that survives, then it's the low level architecture s/r code which
fiddles with the interrupt controllers and leaves them in a state which is
not known to the core code.

Debug patch below. It should make the machine resume again. Emphasis on
"should". Please provide the output of /sys/kernel/debug/tracing/trace
after resume.

The patch didn't apply cleanly: can you tell exact commit or tag it has 
been created against? I tried to hand-wrangle the changes in, but then I 
got compilation errors:

CC      ipc/compat.o
+0x0): multiple definition of `irq_suspend_resume'
kernel/irq/irqdesc.o:(.bss+0x0): first defined here
kernel/irq/manage.o:(.bss+0x8): multiple definition of `irq_suspend_resume'
kernel/irq/irqdesc.o:/home/testrunner/drm-tip/kernel/irq/irqdesc.c:270: 
first defined here
kernel/irq/spurious.o:(.bss+0x0): multiple definition of 
`irq_suspend_resume'

Also, the usage of /sys/power/pm_test was not intuitive to me. Can you 
explain which kind of combinations do you want to test?

Best regards,

Tomi


Thanks,

        tglx

8<-----------

--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -304,7 +304,10 @@ void irq_shutdown(struct irq_desc *desc)
  
  void irq_enable(struct irq_desc *desc)
  {
-       if (!irqd_irq_disabled(&desc->irq_data)) {
+       if (irq_suspend_resume)
+               irq_trace_state("preenable", desc);
+
+       if (!irqd_irq_disabled(&desc->irq_data) && !irq_suspend_resume) {
                unmask_irq(desc);
        } else {
                irq_state_clr_disabled(desc);
@@ -315,10 +318,16 @@ void irq_enable(struct irq_desc *desc)
                        unmask_irq(desc);
                }
        }
+
+       if (irq_suspend_resume)
+               irq_trace_state("postenable", desc);
  }
  
  static void __irq_disable(struct irq_desc *desc, bool mask)
  {
+       if (irq_suspend_resume)
+               irq_trace_state("predisable", desc);
+
        if (irqd_irq_disabled(&desc->irq_data)) {
                if (mask)
                        mask_irq(desc);
@@ -331,6 +340,9 @@ static void __irq_disable(struct irq_des
                        mask_irq(desc);
                }
        }
+
+       if (irq_suspend_resume)
+               irq_trace_state("postdisable", desc);
  }
  
  /**
@@ -390,6 +402,9 @@ static inline void mask_ack_irq(struct i
  
  void mask_irq(struct irq_desc *desc)
  {
+       if (irq_suspend_resume)
+               irq_trace_state("premask", desc);
+
        if (irqd_irq_masked(&desc->irq_data))
                return;
  
@@ -397,17 +412,26 @@ void mask_irq(struct irq_desc *desc)
                desc->irq_data.chip->irq_mask(&desc->irq_data);
                irq_state_set_masked(desc);
        }
+
+       if (irq_suspend_resume)
+               irq_trace_state("postmask", desc);
  }
  
  void unmask_irq(struct irq_desc *desc)
  {
-       if (!irqd_irq_masked(&desc->irq_data))
+       if (irq_suspend_resume)
+               irq_trace_state("preunmask", desc);
+
+       if (!irqd_irq_masked(&desc->irq_data) && !irq_suspend_resume)
                return;
  
  	if (desc->irq_data.chip->irq_unmask) {
                desc->irq_data.chip->irq_unmask(&desc->irq_data);
                irq_state_clr_masked(desc);
        }
+
+       if (irq_suspend_resume)
+               irq_trace_state("postunmask", desc);
  }
  
  void unmask_threaded_irq(struct irq_desc *desc)
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -459,3 +459,11 @@ static inline void irq_remove_debugfs_en
  {
  }
  #endif /* CONFIG_GENERIC_IRQ_DEBUGFS */
+
+bool irq_suspend_resume;
+
+static inline void irq_trace_state(const char *what, struct irq_desc *desc)
+{
+       trace_printk("%s %d state %08x\n", what, irq_desc_get_irq(desc),
+                    irqd_get(&desc->irq_data));
+}
--- a/kernel/irq/pm.c
+++ b/kernel/irq/pm.c
@@ -14,6 +14,8 @@
  
  #include "internals.h"
  
+bool irq_suspend_resume;
+
  bool irq_pm_check_wakeup(struct irq_desc *desc)
  {
        if (irqd_is_wakeup_armed(&desc->irq_data)) {
@@ -120,6 +122,7 @@ void suspend_device_irqs(void)
        struct irq_desc *desc;
        int irq;
  
+	irq_suspend_resume = true;
        for_each_irq_desc(irq, desc) {
                unsigned long flags;
                bool sync;
@@ -127,7 +130,9 @@ void suspend_device_irqs(void)
                if (irq_settings_is_nested_thread(desc))
                        continue;
                raw_spin_lock_irqsave(&desc->lock, flags);
+               irq_trace_state("presuspend", desc);
                sync = suspend_device_irq(desc);
+               irq_trace_state("postsuspend", desc);
                raw_spin_unlock_irqrestore(&desc->lock, flags);
  
  		if (sync)
@@ -172,9 +177,14 @@ static void resume_irqs(bool want_early)
                        continue;
  
  		raw_spin_lock_irqsave(&desc->lock, flags);
+               irq_trace_state("preresume", desc);
                resume_irq(desc);
+               irq_trace_state("postresume", desc);
                raw_spin_unlock_irqrestore(&desc->lock, flags);
        }
+
+       if (!want_early)
+               irq_suspend_resume = false;
  }
  
  /**

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