Re: panic: supervisor write data, protection violation (vn_read/copyout_smap_erms?)

From: Ian FREISLICH <ianfreislich_at_gmail.com>
Date: Sat, 14 Mar 2026 17:35:54 UTC
On 3/14/26 11:54, Michael Butler wrote:
> On 3/14/26 10:23, David Wolfskill wrote:
>> On Sat, Mar 14, 2026 at 09:28:53AM -0400, Michael Butler wrote:
>>> To narrow this .. I can reliably start a kernel built at or before 
>>> commit
>>> 277830b4d3ae.
>>>
>>> On 3/14/26 09:06, Subbsd wrote:
>>>> ...
>>>> uname -a:
>>>>
>>>> FreeBSD host1.my.domain 16.0-CURRENT FreeBSD 16.0-CURRENT #0
>>>> main-f91464171d61: Sat Mar 14 12:35:27 UTC 2026
>>>> root@host1.my.domain:/usr/obj/usr/jails/src/src_16/src/amd64.amd64/ 
>>>> sys/GENERIC
>>>> amd64
>>> ....
>>
>> I updated my headless build machine from main-n284480-9a9f93bcf1aa to
>> main-n284504-f91464171d61 this morning, but it panicked prior to
>> completing the transition to multi-user mode.
>>
>> Checking
>> https://lists.freebsd.org/archives/dev-commits-src-main/2026- 
>> March/040570.html,
>> blame is cast on 914a53570750; further in that thread, kib@ provides a
>> tentative patch (but I have not tested it).
> 
> The patch at the end of this thread appears to solve the problem. Thanks!
I can also confirm that it fixes the same panic for me.

Ian