On 7/8/22 12:54, Dusty Mabe wrote:
>
>
> On 6/30/22 00:04, Pingfan Liu wrote:
>> Currently, kdump may experience failure on some aws aarch64 platform.
>> The final scenario is:
>>
>> [ 79.145089] printk: console [ttyS0] disabled
>> Then the system has no response any more. And after reboot, there is no
>> vmcore generated under /var/crash/. More detail [1].
>>
>> In a short word, it is caused by the irqpoll policy and some unknown
>> acpi issue. The serial device is hot-removed as a pci device.
>>
>> More detailed, the irqpoll policy demands to iterate over all interrupt
>> handler, if the interrupt line is shared, then the handler is
>> dispatched. And acpi handler acpi_irq() is on a shared interrupt line,
>> so it is called. But for some unknown reason, the acpi hardware regs
>> hold wrong state, and the acpi driver decides that a hot-removed event
>> happens on a pci slot, which finally removes the pci serial device.
>>
>> To tackle this issue by removing the irqpoll parameter on aws aarch64
>> platform, until the real root cause in acpi is found and resolved.
>>
>> [1]:
https://bugzilla.redhat.com/show_bug.cgi?id=2080468#c0
>>
>> Signed-off-by: Pingfan Liu <piliu(a)redhat.com>
>> ---
>> kdumpctl | 15 +++++++++++++++
>> 1 file changed, 15 insertions(+)
>>
>> diff --git a/kdumpctl b/kdumpctl
>> index 6188d47..3eb57e3 100755
>> --- a/kdumpctl
>> +++ b/kdumpctl
>> @@ -641,6 +641,18 @@ function remove_kdump_kernel_key()
>> keyctl unlink "$KDUMP_KEY_ID" %:.ima
>> }
>>
>> +function is_aws_aarch64()
>> +{
>> + local _bios_model;
>> +
>> + _bios_model=$(lscpu | grep "BIOS Model name")
>
>
> I'm not sure lscpu is reliable here. I just checked two instance
> types (two I had running were a1.metal and c6g.xlarge) and this didn't work.
>
Actually, it was because I was running `lscpu` as non-root. As root it shows up: