IRQ storm on 570x (Joule)

[jlaako]

On a RefKit image, at least when display is connected during boot time, there's an interrupt storm on IRQ 40. This causes the kernel thread handling the bxt interrupt consume quite a bit of CPU time. This doesn't happen exactly always, but depending on image more or less frequently. There are also other strange symptoms:

1. on boot hex address for ACPI DSDT tables tend to vary
2. depending on image (common, gateway, computervision), systemd startup procedure goes differently, although kernel (including command line), initramfs, firmwares and systemd configuration are the same
3. other misbehavior such as failing shutdown process

This is most likely happen on computervision image, although the boot process should be the same.

Switching meta-intel to use linux-yocto-4.10 seems to make the problem go away, so this seems to be related to linux-intel-4.9.

[rweight]

I would like to try to reproduce these issues on my Joule device. Can I get log information and copies of your RefKit image files for both the linux-intel-4.9 and linux-yocto-4.10 kernels?

[jlaako]

Download link sent over email. You may need to reboot couple of times, indication of problem is high number of interrupts for IRQ 40 in /proc/interrupts and kernel thread [irq/41-bxtwc_ir] taking ~3-5% CPU time in "top".

[rweight]

On 04/04/2017 07:06 AM, Jussi Laako wrote: Download link sent over email. You may need to reboot couple of times, indication of problem is high number of interrupts for IRQ 40 in /proc/interrupts and kernel thread [irq/41-bxtwc_ir] taking ~3-5% CPU time in "top".

Thank you - I will take a look at it today.

[knsathya]

I have been able to reproduce the issue in the build image you sent us. But when I repeat the same experiment with sato or minimal yocto image, it does not happen. May I know what extra changes you have in your image ? If possible can you give me more info on your build ?

[mythi]

@knsathya We don't use poky's config but have our own distro setup with additional features/content. If you need a customized image for debugging purposes, you can take what's in https://github.com/intel/intel-iot-refkit and build that instead.

[knsathya]

@mythi Thanks for the info. I followed your instructions and built refkit-image-common image. But after booting this image I noticed that it uses tty0 as console. I would like to use serial port as my console. Do you know where in conf files I can set the console parameters ?

[knsathya]

@mythi I got around the serial console issue by editing the params in EFI console. But it would be good to know how to do in build conf.

[clsulliv]

I believe the combo app respects the APPEND variable. In which case you would do something like the following: APPEND += "console=ttyS0,115200"

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--- Cal

On 04/12/2017 04:04 PM, Sathyanarayanan Kuppuswamy Natarajan wrote: @mythi <https://github.com/mythi> I got around the serial console issue by editing the params in EFI console. But it would be good to know how to do in build conf. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#3 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AH7c5ErlbkyeUlkZSuoJ4-IaXfdtp6S7ks5rvViEgaJpZM4Mvi6R>.

[mythi]

Correct, APPEND works.

However, we do have the right console set for 570x through RMC. For RMC to detect the board correctly, you'll need BIOS v161. That's a limitation we're working on addressing.

[knsathya]

Following patches fix the issue. Its sent to upstream for review.

https://patchwork.kernel.org/patch/9681511/
https://patchwork.kernel.org/patch/9681513/