Re: Question regarding RT patches for ARM
Hi Eric, On 15 May 2017 at 16:12, Eric Nelson <eric@nelint.com> wrote:
Hi Fawad,
发自网易邮箱大师 On 05/15/2017 20:44, Fawad Lateef wrote:
Hi All,
I am working on custom i.MX6 quad hardware and using RT patches for almost latest stable kernel 4.9 and facing some weird system stall OR 'unhandled page fault - exceptions'.
I'm not sure about the unhandled page fault, but the stalls may be because of the SDMA driver.
See this patch in the Freescale/NXP community for kernel 4.1: https://github.com/Freescale/meta-freescale/blob/master/recipes-kernel/linux...
Thanks for the patch link. I will give it a try.
Regards,
Eric
Regards, Fawad Lateef
Hi, On 15 May 2017 at 16:20, Fawad Lateef <fawadlateef@gmail.com> wrote:
Hi Eric,
On 15 May 2017 at 16:12, Eric Nelson <eric@nelint.com> wrote:
Hi Fawad,
发自网易邮箱大师 On 05/15/2017 20:44, Fawad Lateef wrote:
Hi All,
I am working on custom i.MX6 quad hardware and using RT patches for almost latest stable kernel 4.9 and facing some weird system stall OR 'unhandled page fault - exceptions'.
I'm not sure about the unhandled page fault, but the stalls may be because of the SDMA driver.
See this patch in the Freescale/NXP community for kernel 4.1: https://github.com/Freescale/meta-freescale/blob/master/recipes-kernel/linux...
Thanks for the patch link. I will give it a try.
Talked to hardware manufacturer and they applied the patch. Still that SDMA is only used for NOR flash and only u-boot and its environment are stored in nor flash. So not sure if that is going to help in any case. So I would really like few more suggestions OR confirmations about ARM (cortex-A9 based imx6) (preemept)-RT support/patches are stable and can be used for final products. Thanks
Regards,
Eric
Regards,
Fawad Lateef
Hi Fawad, On 05/17/2017 06:40 AM, Fawad Lateef wrote:
On 15 May 2017 at 16:20, Fawad Lateef <fawadlateef@gmail.com> wrote:
Hi Eric, On 15 May 2017 at 16:12, Eric Nelson <eric@nelint.com> wrote:
Hi Fawad,
发自网易邮箱大师 On 05/15/2017 20:44, Fawad Lateef wrote:
Hi All,
I am working on custom i.MX6 quad hardware and using RT patches for almost latest stable kernel 4.9 and facing some weird system stall OR 'unhandled page fault - exceptions'.
I'm not sure about the unhandled page fault, but the stalls may be because of the SDMA driver.
See this patch in the Freescale/NXP community for kernel 4.1: https://github.com/Freescale/meta-freescale/blob/master/recipes-kernel/linux...
Thanks for the patch link. I will give it a try.
Talked to hardware manufacturer and they applied the patch.
Still that SDMA is only used for NOR flash and only u-boot and its environment are stored in nor flash. So not sure if that is going to help in any case.
SDMA is used for much more than NOR flash (SSI, USB, and sometimes UARTs).
So I would really like few more suggestions OR confirmations about ARM (cortex-A9 based imx6) (preemept)-RT support/patches are stable and can be used for final products.
I don't have any experience with the RT patches on 4.9 or later kernels, but do know that they're being used on i.MX6 with the vendor kernels (3.10.x, 4.1.x). I believe Alison Chaiken mentioned using them with 4.9 kernels: http://elinux.org/images/4/42/IRQs-_the_Hard%2C_the_Soft%2C_the_Threaded_and... https://www.youtube.com/watch?v=-pehAzaP1eg&feature=youtu.be&list=PLbzoR-pLr... Regards, Eric
On 2017-05-17 07:45:39 [-0700], Eric Nelson wrote:
Hi Fawad, Hi Fawad,
On 05/17/2017 06:40 AM, Fawad Lateef wrote:
I'm not sure about the unhandled page fault, but the stalls may be because of the SDMA driver.
See this patch in the Freescale/NXP community for kernel 4.1: https://github.com/Freescale/meta-freescale/blob/master/recipes-kernel/linux...
That is something I see for the first time. The description says that it leads to this stall but it fails to explain _how_ it got there.
Thanks for the patch link. I will give it a try.
Talked to hardware manufacturer and they applied the patch.
Still that SDMA is only used for NOR flash and only u-boot and its environment are stored in nor flash. So not sure if that is going to help in any case.
SDMA is used for much more than NOR flash (SSI, USB, and sometimes UARTs).
So I would really like few more suggestions OR confirmations about ARM (cortex-A9 based imx6) (preemept)-RT support/patches are stable and can be used for final products.
I don't have any experience with the RT patches on 4.9 or later kernels, but do know that they're being used on i.MX6 with the vendor kernels (3.10.x, 4.1.x).
I just looked into a few boot logs and it seems the Phyflex board (imx6 quad) bootet v4.9.27-rt18, run cyclictest including some tests and nothing produced this "unhandled page fault" you mention here. This includes the previous RT version in the v4.9 line. Of this "page fault" happens on boot, it has to do something without your .config + hw combination. If it happens at rune-time it is probably triggered by a driver or an application is triggering this.
Regards,
Eric
Sebastian
participants (3)
-
Eric Nelson -
Fawad Lateef -
Sebastian Andrzej Siewior