Re: USB Attached SCSI breakage due no udev involvement

[Greg KH]

On Sun, May 10, 2020 at 03:35:34PM +0700, Dio Putra wrote:
> On 5/10/20 2:32 PM, Greg KH wrote:
> > On Sun, May 10, 2020 at 02:10:04PM +0700, Dio Putra wrote:
> >> On 5/10/20 1:54 PM, Greg KH wrote:
> >>> On Sun, May 10, 2020 at 01:48:24PM +0700, Dio Putra wrote:
> >>>> On 5/10/20 12:47 PM, Greg KH wrote:
> >>>>> On Sun, May 10, 2020 at 09:55:57AM +0700, Dio Putra wrote:
> >>>>>> Hi, it's first time for me to report user-space breakage in here, so
> >>>>>> i'm begging your pardon.
> >>>>>>
> >>>>>> I want to report that Linux 5.4 breaking my USB mount workflow due
> >>>>>> udevadm monitor report here (I'm using vanilla kernel 5.4.39 on
> >>>>>> Slackware64 Current and vanilla kernel 4.4.221 on Slackware64 14.2):
> >>>>>
> >>>>> <snip>
> >>>>>
> >>>>> Sorry, but what actually changed that you can see in the logs?
> >>>> Sorry, what do you mean? The dmesg log or the kernel changelogs?
> >>>
> >>> Either, your message made them pretty impossible to compare with all of
> >>> the line-wrapping :(
> >>>
> >> I'm so sorry for first message mess, because that message has been sent by
> >> Gmail Website. Can I send my logs as attachment? I try to convenient everyone
> >> here. ( FYI, I just switched to Thunderbird with these settings:
> >> https://www.kernel.org/doc/html/v4.12/process/email-clients.html#thunderbird-gui ) 
> > 
> > Sure, attachments work, but better yet, if you can show the difference
> > in a few lines that is much nicer than having to dig through large
> > numbers of log files.
> > 
> Okay, I'll attach long messages and trim it as far as I can.

Again, I really do not understand what exactly is "not working".

Please explain that when you send the new log messages.

> >>>>> What functionality broke?  What used to work that no longer does work?
> >>>>>
> >>>> Yes, it supposed that just work and kernel could talk with udev, not just handled by the kernel.
> >>>
> >>> I don't understand, what functionality changed?  What exactly used to
> >>> work that no longer does?
> >> linux-5.4 has been never called the udev dependencies whereas
> >> linux-4.4 will call any udev dependencies if necessary, that's the problem.
> > 
> > I do not understand what exactly you mean by "call udev dependencies".
> > 
> > udev is used to create symlinks and set user/group permissions on device
> > nodes in /dev/ which is created by devtmpfs.  What exactly is not
> > happening in your /dev/ with the move to a newer kernel?
> > 
> Would I send my dmesg log with "udev.log-priority=debug" as attachment then?
> 
> >>> Did you change anything else other than the kernel on your system?  Did
> >>> you change to a newer version of udev/systemd or anything else?
> >>>
> >> I'm using eudev-master from their official mirror github:
> >> https://github.com/gentoo/eudev
> > 
> > Have you contacted the eudev developers to see if something different
> > needs to be set in your kernel when moving 4 years in kernel development
> > forward?  Are you sure you have all the correct config options enabled?
> > 
> It's my bad not to contact the eudev developers first. However I'm not quite
> sure to contact the eudev developers would solve the problem, but CMIIW.
> 
> > Why such a huge leap forward all at once, how about going from 4.4.y to
> > 4.9.y and then 4.14.y and then 5.4.y?  That might help narrow things
> > down a bit easier.
> > 
> Unfortunately I need to think twice due almost ran out of electricity
> here every time I power on my laptop for long time. So maybe I can't.
> 
> But if these steps are necessary, I'll think solution later.

Why would it take a long time to do this type of change?

thanks,

greg k-h