Re: FreeBSD arm64 Azure panic during reboot in add_route

On 9/4/23 05:13, Souradeep Chakrabarti wrote:
> Hi
> I am working on bringing FreeBSD on Azure ARM64. When I am rebooting the FreeBSD arm64 in Azure public preview,
> we are hitting following panic sometime for page fault:
> db_trace_self_wrapper() at db_trace_self_wrapper+0x30
> vpanic() at vpanic+0x13c
> panic() at panic+0x44
> data_abort() at data_abort+0x30c
> handle_el1h_sync() at handle_el1h_sync+0x14
> --- exception, esr 0x8600000e
> (null)() at 0xffffa0000c93bb00
> add_route() at add_route+0xc4
> add_route_flags() at add_route_flags+0x1b0
> rib_add_route() at rib_add_route+0x324
> ifa_maintain_loopback_route() at ifa_maintain_loopback_route+0xf4
> in6_update_ifa() at in6_update_ifa+0x994
> in6_ifattach() at in6_ifattach+0x1bc
> in6_if_up() at in6_if_up+0x90
> if_up() at if_up+0xd8
> ifhwioctl() at ifhwioctl+0xb7c
> ifioctl() at ifioctl+0x860
> kern_ioctl() at kern_ioctl+0x2dc
> sys_ioctl() at sys_ioctl+0x118
> do_el0_sync() at do_el0_sync+0x520
> handle_el0_sync() at handle_el0_sync+0x44
> 
> The panic is coming when add_route is called for loopback interface ipv6 attachment.
> Upon more investigating it looks like the panic happens in rib_notify() .
> 
> Please let me know how to debug it further to find the RC.
> I have already opened a bug to track it : https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=272666
> 

Hi,

I note that Andy has an unanswered question in that PR (comment #9) from 
2023/08/14.  Do you have a coredump from this that you can poke around 
in easily with kgdb?

Thanks,

Kyle Evans