Re: port-evbarm/60269: System hangs NetBSD/evbarm(aarch64) 11.0_RC4

[Nick Hudson <nick.hudson%gmx.co.uk@localhost>]

On 16/05/2026 05:25, oshima-ya%yagoto-urayama.jp@localhost via gnats wrote:
>> Number:         60269
>> Category:       port-evbarm
>> Synopsis:       System hangs NetBSD/evbarm(aarch64) 11.0_RC4
>> Confidential:   no
>> Severity:       serious
>> Priority:       high
>> Responsible:    port-evbarm-maintainer
>> State:          open
>> Class:          sw-bug
>> Submitter-Id:   net
>> Arrival-Date:   Sat May 16 04:25:00 +0000 2026
>> Originator:     Yasushi Oshima
>> Release:        11.0_RC4
>> Organization:
>> Environment:
> NetBSD nable 11.0_RC4 NetBSD 11.0_RC4 (GENERIC64) #0: Thu May 14 09:46:21 JST 2026  oshima@sudachi:/export/netbsd-11/20260514/obj/evbarm64/sys/arch/evbarm/compile/GENERIC64 evbarm
>> Description:
> After upgrading NetBSD/evbarm (aarch64)to 11.0_RC4 on my RasPi4, the system frequently hangs. This often occurs while building several applications from pkgsrc. As a result, a response of shell or any commands suddenly stops, and SSH sessions from the network are disconnected.
> When the system hangs, it is possible to start ddb from the console using Ctrl-Alt-ESC. I found the process states by ps revealed several processes stuck on rwlock.
>  (see https://x.com/oshimyja/status/2054966172375032207/photo/1)
> For example, this frequently happens when building www/firefox. It can also occur during daily cron jobs.
> No such issues were observed in 11.0_RC2.
> I don't know whether other architectures are affected.
> At least, it doesn't happen on my amd64 11.0_RC4 environment.
> This system is booted from a USB stick, and no crash dumps have been obtained.
>> How-To-Repeat:
> On NetBSD/evbarm(GENERIC64) 11.0_RC4,
> Build some pkgsrcs
>> Fix:
> None, but I check the source change history and found the following changes, then backout these and rebuild libc and related components, no further hangs have occurred so far:
> https://mail-index.netbsd.org/source-changes/2026/05/07/msg161941.html
> I think some of these changes is causing the issue.

Sorry to hear you're having issues with 11.0_RC4.

I'm not sure this commit is the cause however as the files touch by that commit aren't used on aarch64

nick@zoom:~/netbsd/netbsd-11/src$ find ../obj.evbarm64-el/ -name "atomic_cas*cas*o"
nick@zoom:~/netbsd/netbsd-11/src$

and libc.so doesn't change

Maybe I'm missing something?