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* Bug report for kernel v4.15-rc8+
@ 2021-08-06 15:45 blinkin
  2021-08-10  6:46 ` Thomas Gleixner
  0 siblings, 1 reply; 10+ messages in thread
From: blinkin @ 2021-08-06 15:45 UTC (permalink / raw)
  To: Thomas Gleixner; +Cc: linux-kernel

Hello,

I think I found a bug in kernel 4.15-rc8+. Git bisect tells me that the incriminating commit is https://github.com/openSUSE/kernel/commit/a0c9259dc4e1923a98356967ce8b732da1979df8.

The bug doesn't seem widespread and it may be affecting only my hardware (Asuspro P2530UJ laptop).
I also found a workaround (boot kernel parameters combination) thanks to your comments on this (seemingly unrelated) bugreport: https://bugzilla.kernel.org/show_bug.cgi?id=208097

I'm not sure where and how to report it, the kernel I used for the tests is built from the opensuse tree but it looks like an upstream bug.
Can you give me pointers on how to proceed from here? I can provide informations about the symptoms, the hardware config and the workaround but I know nothing about CPU/IRQ management in the linux kernel.

Thanks for your time

^ permalink raw reply	[flat|nested] 10+ messages in thread
* Re: Bug report for kernel v4.15-rc8+
@ 2021-12-17 13:31 blinkin
  0 siblings, 0 replies; 10+ messages in thread
From: blinkin @ 2021-12-17 13:31 UTC (permalink / raw)
  To: Thomas Gleixner; +Cc: linux-kernel, Rafael J. Wysocki, Len Brown, linux-acpi

hello, any news on this?

----- Messaggio originale -----
Da: "Thomas Gleixner" <tglx@linutronix.de>
A: blinkin@email.it
Cc: "linux-kernel" <linux-kernel@vger.kernel.org>, "Rafael J. Wysocki" <rafael@kernel.org>, "Len Brown" <lenb@kernel.org>, linux-acpi@vger.kernel.org
Inviato: Mercoledì, 11 agosto 2021 16:20:41
Oggetto: Re: Bug report for kernel v4.15-rc8+

On Wed, Aug 11 2021 at 15:51, blinkin@email.it wrote:
> 1) You're booting with an out of tree module
>
>   Uninstalled virtualbox, reproduced same behavior without the module.
>   dmesg outputs attached with and without the workaround
>   (dmesg_novboxdrv_clean.txt and dmesg_novboxdrv_irqaffinity0.txt)

Ok.

> 2) Please provide information what is consuming 90% of a CPU
>
>   top shows a kworker process consistently at 50% without the
>   workaround, 60% with the workaround. No significant activity amounts
>   from other processes.  Sometimes that 50% is split between two
>   kworker processes for a short time.  CPU core #0 activity is a
>   constant 60% without the workaround, 90% with the workaround

That's broken. /proc/interrupts gives some hint:

1) Stock kernel

>             CPU0       CPU1       CPU2       CPU3       
>    0:         10          0          0          0  IR-IO-APIC    2-edge      timer
>    1:          0          0          0          9  IR-IO-APIC    1-edge      i8042
>    8:          0          1          0          0  IR-IO-APIC    8-edge      rtc0
>    9:          0     923411          0          0  IR-IO-APIC    9-fasteoi   acpi

900k ACPI interrupts right after boot

>             CPU0       CPU1       CPU2       CPU3       
>    0:         10          0          0          0  IR-IO-APIC    2-edge      timer
>    1:          0          0          0         11  IR-IO-APIC    1-edge      i8042
>    8:          0          1          0          0  IR-IO-APIC    8-edge      rtc0
>    9:          0    4869059          0          0  IR-IO-APIC    9-fasteoi   acpi

One minute later it's 4.8M

With affinity forced to CPU0 it's even more:

>             CPU0       CPU1       CPU2       CPU3       
>    0:         10          0          0          0  IR-IO-APIC    2-edge      timer
>    1:          9          0          0          0  IR-IO-APIC    1-edge      i8042
>    8:          1          0          0          0  IR-IO-APIC    8-edge      rtc0
>    9:    7576456          0          0          0  IR-IO-APIC    9-fasteoi   acpi

7.5M right after boot

>             CPU0       CPU1       CPU2       CPU3       
>    0:         10          0          0          0  IR-IO-APIC    2-edge      timer
>    1:         11          0          0          0  IR-IO-APIC    1-edge      i8042
>    8:          1          0          0          0  IR-IO-APIC    8-edge      rtc0
>    9:   10992420          0          0          0  IR-IO-APIC    9-fasteoi   acpi

10.9M after one minute. Though the delta between right after boot and 1
minute later is in the same ballpark.

Cc'ed the ACPI people for clues.

Thanks,

        tglx

^ permalink raw reply	[flat|nested] 10+ messages in thread
* Re: Bug report for kernel v4.15-rc8+
@ 2022-06-10  9:52 blinkin
  2022-06-10 13:17 ` Rafael J. Wysocki
  0 siblings, 1 reply; 10+ messages in thread
From: blinkin @ 2022-06-10  9:52 UTC (permalink / raw)
  To: Thomas Gleixner; +Cc: linux-kernel, Rafael J. Wysocki, Len Brown, linux-acpi

hello, any news on this?

----- Messaggio originale -----
Da: "Thomas Gleixner" <tglx@linutronix.de>
A: blinkin@email.it
Cc: "linux-kernel" <linux-kernel@vger.kernel.org>, "Rafael J. Wysocki" <rafael@kernel.org>, "Len Brown" <lenb@kernel.org>, linux-acpi@vger.kernel.org
Inviato: Mercoledì, 11 agosto 2021 16:20:41
Oggetto: Re: Bug report for kernel v4.15-rc8+

On Wed, Aug 11 2021 at 15:51, blinkin@email.it wrote:
> 1) You're booting with an out of tree module
>
>   Uninstalled virtualbox, reproduced same behavior without the module.
>   dmesg outputs attached with and without the workaround
>   (dmesg_novboxdrv_clean.txt and dmesg_novboxdrv_irqaffinity0.txt)

Ok.

> 2) Please provide information what is consuming 90% of a CPU
>
>   top shows a kworker process consistently at 50% without the
>   workaround, 60% with the workaround. No significant activity amounts
>   from other processes.  Sometimes that 50% is split between two
>   kworker processes for a short time.  CPU core #0 activity is a
>   constant 60% without the workaround, 90% with the workaround

That's broken. /proc/interrupts gives some hint:

1) Stock kernel

>             CPU0       CPU1       CPU2       CPU3       
>    0:         10          0          0          0  IR-IO-APIC    2-edge      timer
>    1:          0          0          0          9  IR-IO-APIC    1-edge      i8042
>    8:          0          1          0          0  IR-IO-APIC    8-edge      rtc0
>    9:          0     923411          0          0  IR-IO-APIC    9-fasteoi   acpi

900k ACPI interrupts right after boot

>             CPU0       CPU1       CPU2       CPU3       
>    0:         10          0          0          0  IR-IO-APIC    2-edge      timer
>    1:          0          0          0         11  IR-IO-APIC    1-edge      i8042
>    8:          0          1          0          0  IR-IO-APIC    8-edge      rtc0
>    9:          0    4869059          0          0  IR-IO-APIC    9-fasteoi   acpi

One minute later it's 4.8M

With affinity forced to CPU0 it's even more:

>             CPU0       CPU1       CPU2       CPU3       
>    0:         10          0          0          0  IR-IO-APIC    2-edge      timer
>    1:          9          0          0          0  IR-IO-APIC    1-edge      i8042
>    8:          1          0          0          0  IR-IO-APIC    8-edge      rtc0
>    9:    7576456          0          0          0  IR-IO-APIC    9-fasteoi   acpi

7.5M right after boot

>             CPU0       CPU1       CPU2       CPU3       
>    0:         10          0          0          0  IR-IO-APIC    2-edge      timer
>    1:         11          0          0          0  IR-IO-APIC    1-edge      i8042
>    8:          1          0          0          0  IR-IO-APIC    8-edge      rtc0
>    9:   10992420          0          0          0  IR-IO-APIC    9-fasteoi   acpi

10.9M after one minute. Though the delta between right after boot and 1
minute later is in the same ballpark.

Cc'ed the ACPI people for clues.

Thanks,

        tglx

^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2022-06-10 13:18 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2021-08-06 15:45 Bug report for kernel v4.15-rc8+ blinkin
2021-08-10  6:46 ` Thomas Gleixner
2021-08-10 14:05   ` blinkin
2021-08-10 17:09     ` Thomas Gleixner
2021-08-11 13:51       ` blinkin
2021-08-11 14:20         ` Thomas Gleixner
2021-09-24 10:23           ` blinkin
  -- strict thread matches above, loose matches on Subject: below --
2021-12-17 13:31 blinkin
2022-06-10  9:52 blinkin
2022-06-10 13:17 ` Rafael J. Wysocki

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