Re: v6.1-rc1: Regression in notification of sethostname changes #forregzbot

[Thorsten Leemhuis <regressions@leemhuis.info>]

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#regzbot fixed-by: 54de93cd8740d5

On 20.10.22 14:43, Thorsten Leemhuis wrote:
> On 19.10.22 10:29, Torsten Hilbrich wrote:
>> Hello Petr,
>>
>> your commit
>>
>> commit bfca3dd3d0680fc2fc7f659a152234afbac26e4d
>> Author: Petr Vorel <pvorel@suse.cz>
>> Date:   Thu Sep 1 21:44:03 2022 +0200
>>
>>     kernel/utsname_sysctl.c: print kernel arch
>>     
>>     Print the machine hardware name (UTS_MACHINE) in /proc/sys/kernel/arch.
>>     
>>     This helps people who debug kernel with initramfs with minimal environment
>>     (i.e.  without coreutils or even busybox) or allow to open sysfs file
>>     instead of run 'uname -m' in high level languages.
>>
>> broke the notification mechanism between the sethostname syscall and the pollers of /proc/sys/kernel/hostname.
>>
>> The table uts_kern_table is addressed within uts_proc_notify by the enum value, however no new enum value was added in "enum uts_proc".
>>
>> I noticed the problem when journald-systemd failed to detect hostname changes made with the sethostname syscall (as used by the hostname tool).
>> When setting the hostname through /proc/sys/kernel/hostname the poll notification was working.
> 
> Thanks for the report. To be sure below issue doesn't fall through the
> cracks unnoticed, I'm adding it to regzbot, my Linux kernel regression
> tracking bot:
> 
> #regzbot ^introduced bfca3dd3d0
> #regzbot ignore-activity
> 
> This isn't a regression? This issue or a fix for it are already
> discussed somewhere else? It was fixed already? You want to clarify when
> the regression started to happen? Or point out I got the title or
> something else totally wrong? Then just reply -- ideally with also
> telling regzbot about it, as explained here:
> https://linux-regtracking.leemhuis.info/tracked-regression/
> 
> Reminder for developers: When fixing the issue, add 'Link:' tags
> pointing to the report (the mail this one replies to), as explained for
> in the Linux kernel's documentation; above webpage explains why this is
> important for tracked regressions.
> 
> Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
> 
> P.S.: As the Linux kernel's regression tracker I deal with a lot of
> reports and sometimes miss something important when writing mails like
> this. If that's the case here, don't hesitate to tell me in a public
> reply, it's in everyone's interest to set the public record straight.