Hi Andy, On 6/27/2018 2:47 AM, Andy Strohman wrote: > On Sun, Jun 17, 2018 at 11:31 PM, <sricharan@xxxxxxxxxxxxxx> wrote: >> Hi Andy, >> >> On 2018-06-16 06:37, Andy Strohman wrote: >>> >>> Hi, >>> >>> I'm trying to get kexec to work consistently for ipq4019. I load >>> the crash kernel like this: >>> >>> kexec --type zImage -p zImage-initramfs >>> --dtb=image-qcom-ipq4019-eap1300.dtb --append="maxcpus=1 >>> reset_devices" --image-size=34419456 >>> >>> I have reserved 64MB of memory for the crash kernel with parameter: >>> crashkernel=64M >>> >>> This seems to work ~70% of the time. When it doesn't work, I see the >>> "bye!" message followed by a 5-10 second hang without output. Then >>> the machine resets. >>> >>> I've been testing with: >>> echo c > /proc/sysrq-trigger >>> >>> Does anyone have an idea of what may be causing the failures or how >>> to troubleshoot this? >>> >> >> I will try to reproduce this and get back to you shortly. >> >> Regards, >> Sricharan >> >> >>> I'm using OpenWRT with kernel 4.14.37. I added the following patch >>> in order to load the crash kernel: >>> >>> --- a/arch/arm/mach-qcom/platsmp.c >>> +++ b/arch/arm/mach-qcom/platsmp.c >>> @@ -332,6 +332,12 @@ static void __init qcom_smp_prepare_cpus >>> } >>> } >>> >>> +/* Needed by kexec and platform_can_cpu_hotplug() */ >>> +int qcom_cpu_kill(unsigned int cpu) >>> +{ >>> + return 1; >>> +} >>> + >>> static const struct smp_operations smp_msm8660_ops __initconst = { >>> .smp_prepare_cpus = qcom_smp_prepare_cpus, >>> .smp_secondary_init = qcom_secondary_init, >>> @@ -358,6 +364,7 @@ static const struct smp_operations qcom_ >>> .smp_boot_secondary = kpssv2_boot_secondary, >>> #ifdef CONFIG_HOTPLUG_CPU >>> .cpu_die = qcom_cpu_die, >>> + .cpu_kill = qcom_cpu_kill, >>> #endif >>> }; >>> CPU_METHOD_OF_DECLARE(qcom_smp_kpssv2, "qcom,kpss-acc-v2", >>> &qcom_smp_kpssv2_ops); >>> >>> >>> Thanks, >>> >>> Andy > > Hi Sricharan, > > Thanks for your response. Did you get a chance to try this out? If > so, were you able to reproduce? > I have been trying to kexec while chroot'ing for a different reason. I did not observe a issue so far. But that is with a 4.4.60 openwrt kernel. Can you point me a link to the kernel that you are trying with ? Regards, Sricharan -- "QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html