Re: [PATCH v5 0/3] arm64: dts: qcom: add dts for sa8540p-ride board

[Brian Masney <bmasney@redhat.com>]

On Tue, Oct 04, 2022 at 09:28:16AM -0400, Eric Chanudet wrote:
> I followed the instructions above and linux-next-20220930 booted on the
> QDrive3 to a prompt. It then hanged after a couple minutes and rebooted
> in Sahara mode:
>     B -   1662280 - Sahara Init
>     B -   1665422 - Sahara Open
> 
> There seems to be no trace from the kernel, this happened consistently
> over 3 boots.
> 
> I asked Brian, he mentioned he only booted to prompt so that may have
> happened unbeknownst to him as well.

Good catch, Eric!

Parikshit: I found a way to reproduce the crash and isolated the issue
to the qcom_q6v5_pas driver. Here's how you can reproduce the crash
that we're seeing:

1) Use my instructions at [1] to build an upstream kernel with the arm64
   defconfg. Today I used linux-next-20221017.

2) Copy the modules to the root filesystem. Before you reboot, mv
   /lib/modules/6.0.0-next-20221017-xxx to
   /lib/modules/6.0.0-next-20221017-xxx-old so that the modules are not
   automatically loaded on startup.

3) Reboot, and run lsmod and verify that no modules are loaded.

4) cd /lib/modules/6.0.0-next-20221017-xxx-old

5) Now load the modules that work as expected that are loaded with the
   upstream arm64 defconfig:

        insmod ./kernel/net/rfkill/rfkill.ko
        insmod ./kernel/arch/arm64/crypto/crct10dif-ce.ko
        insmod ./kernel/net/qrtr/qrtr.ko
        insmod ./kernel/drivers/phy/qualcomm/phy-qcom-snps-femto-v2.ko
        insmod ./kernel/drivers/soc/qcom/llcc-qcom.ko
        insmod ./kernel/drivers/soc/qcom/qmi_helpers.ko
        insmod ./kernel/drivers/remoteproc/qcom_sysmon.ko
        insmod ./kernel/drivers/remoteproc/qcom_q6v5.ko
        insmod ./kernel/drivers/rpmsg/qcom_glink_smem.ko
        insmod ./kernel/drivers/soc/qcom/socinfo.ko
        insmod ./kernel/drivers/remoteproc/qcom_pil_info.ko
        insmod ./kernel/drivers/remoteproc/qcom_common.ko
        insmod ./kernel/drivers/watchdog/qcom-wdt.ko
        insmod ./kernel/fs/fuse/fuse.ko
        insmod ./kernel/drivers/soc/qcom/mdt_loader.ko

6) Wait a few minutes to be sure that everything is working as expected
   on the board.

7) Make the board go BOOM:

        insmod ./kernel/drivers/remoteproc/qcom_q6v5_pas.ko

We don't know how or have the tools to analyze the ramdumps from the
Qualcomm firmware at Red Hat, so we're flying blind right now.

[1] https://lore.kernel.org/lkml/YzsciFeYpvv%2F92CG@x1/

Brian