Re: [gentoo-user] udev-191 bit me. Insufficient ptys

[Michael Mol]

On Thu, Jan 31, 2013 at 9:05 AM, Michael Mol <mikemol@×××××.com> wrote:
> On Thu, Jan 31, 2013 at 8:47 AM, Michael Mol <mikemol@×××××.com> wrote:
>> On Thu, Jan 31, 2013 at 8:26 AM, Michael Mol <mikemol@×××××.com> wrote:
>>> On Wed, Jan 30, 2013 at 11:48 PM, Canek Peláez Valdés <caneko@×××××.com> wrote:
>>>> On Wed, Jan 30, 2013 at 10:45 PM, Canek Peláez Valdés <caneko@×××××.com> wrote:
>>>>> On Wed, Jan 30, 2013 at 9:35 PM, Michael Mol <mikemol@×××××.com> wrote:
>>>>>> So, I botched the upgrade to udev-191. I thought I'd followed the
>>>>>> steps, but I apparently only covered them for one machine, not both.
>>>>>>
>>>>>> The news item instructions specified that I had to remove
>>>>>> udev-postmount from my runlevels. I didn't have udev-postmount in my
>>>>>> runlevels, so I didn't remove it. Turns out, that dictum also applies
>>>>>> to udev-mount. So after removing that[1], I was able to at least boot
>>>>>> again.
>>>>>>
>>>>>> Udev also complained about DEVTMPFS not being enabled in the
>>>>>> kernel.[2]  I couldn't get into X, but I could log in via getty and a
>>>>>> plain old vt, so I enabled it, rebuilt the kernel, installed it and
>>>>>> rebooted...and now that's presumably covered.
>>>>>>
>>>>>> I'm now able to get into X, but when I try to run an xterm, it fails.
>>>>>> Checking ~/.xsession_errors, I find:
>>>>>>
>>>>>> xterm: Error 32, error 2: No such file or directory
>>>>>> Reason: get_pty: not enough ptys
>>>>>
>>>>> Do you have CONFIG_LEGACY_PTYS=y?  If so, do you really need it? A
>>>>> little over a year ago[1] I had an annoying issue for having that
>>>>> option enabled in my kernel, with a lot of virtual ttys reported in
>>>>> systemctl. This is a shot in the dark (I really don't know if it's
>>>>> related to your problem), but perhaps having the LEGACY_PTYS option
>>>>> enabled somehow depleted your available pseudo terminals (which any X
>>>>> terminal needs to run)? I suppose screen is also out of the question
>>>>> for the same reason.
>>>
>>> No, I don't have CONFIG_LEGACY_PTYs. I do have UNIX98 PTYs, and I
>>> tried enabling alternate namespaces, but that didn't help either.
>>>
>>>>
>>>> Also related, if you have LEGACY_PTYS:
>>>>
>>>> "LEGACY_PTY_COUNT:
>>>>
>>>> The maximum number of legacy PTYs that can be used at any one time.
>>>> The default is 256, and should be more than enough.  Embedded
>>>> systems may want to reduce this to save memory.
>>>>
>>>> When not in use, each legacy PTY occupies 12 bytes on 32-bit
>>>> architectures and 24 bytes on 64-bit architectures."
>>>
>>> Yeah, I'm not using CONFIG_LEGACY_PTY, so LEGACY_PTY_COUNT doesn't
>>> even make itself available in menuconfig.
>>
>> Hm. Some googling suggests this might be a permissions issue.
>>
>> I do have consolekit enabled, but I'm using gdm, so I'd expect that to
>> take care of itself. (Although screen fails to launch from vt1, so
>> it's not a consolekit problem.)
>
> OK, it looks like /dev/pts is not mounted. But darned if I know
> why...Isn't udev supposed to handle that?

SOLVED.

Two pieces missing.

One, I didn't notice the "unable to create /dev/pts" and "unable to
create /dev/shm" messages in the boot sequence...and they didn't
appear in /var/log/messages for whatever reason.

Two, I'm not using an initramfs on this machine, so in *addition* to
needing to have CONFIG_DEVTMPFS enabled, I also needed to have
CONFIG_DEVTMPFS_MOUNT enabled.

Rebuilding the kernel with that, and rebooting, seems to have fixed things.

--
:wq