Re: nosh version 1.31

From: Guillermo <gdiazhartusch_at_gmail.com>
Date: Fri, 20 Jan 2017 20:37:08 -0300

Hello,

2017-01-14 8:26 GMT-03:00 Jonathan de Boyne Pollard:
>
> The nosh package is now up to version 1.31 .

Some comments:

1) Programs from at least util-linux get confused by the way
system-manager(8) mounts some of the filesystems from
source/api_mounts.cpp. The problem seems to be those whose
corresponding array of iovecs doesn't have a 'from' element, which
IIUC results in a mount(2) call for them with an empty string as the
'source' argument in source/nmount.cpp. And it looks like other
programs don't expect that and behave weirdly:

$ ps -p 1 -o pid,tname,stat,time,args
 PID TTY STAT TIME COMMAND
    1 ? Ss 00:00:00 /sbin/system-manager

$ mount
mount: /proc/self/mountinfo: parse error: ignore entry at line 2.
mount: /proc/self/mountinfo: parse error: ignore entry at line 3.
mount: /proc/self/mountinfo: parse error: ignore entry at line 4.
mount: /proc/self/mountinfo: parse error: ignore entry at line 5.
/dev/sda4 on / type ext4 (rw,relatime,data=ordered)
none on /proc
none on /sys
none on /dev
none on /dev/pts
tmpfs on /run type tmpfs (rw,nosuid,nodev,size=206124k,mode=755)
tmpfs on /run/shm type tmpfs (rw,nosuid,nodev,noexec,size=515312k)
[...]

$ findmnt --list
findmnt: /proc/self/mountinfo: parse error at line 2
findmnt: /proc/self/mountinfo: parse error at line 3
findmnt: /proc/self/mountinfo: parse error at line 4
findmnt: /proc/self/mountinfo: parse error at line 5
TARGET SOURCE FSTYPE OPTIONS
/ /dev/sda4 ext4 rw,relatime,data=ordered
/proc
/sys
/dev
/dev/pts
/run tmpfs tmpfs rw,nosuid,nodev,size=206124k,mode=755
/run/shm tmpfs tmpfs rw,nosuid,nodev,noexec,size=515312k
[...]

$ cat /proc/self/mountinfo
14 0 8:4 / / rw,relatime - ext4 /dev/sda4 rw,data=ordered
15 14 0:4 / /proc rw,nosuid,nodev,relatime - proc rw
16 14 0:14 / /sys rw,nosuid,nodev,noexec,relatime - sysfs rw
17 14 0:6 / /dev rw,nosuid - devtmpfs rw,size=10240k,nr_inodes=128775,mode=755
18 17 0:15 / /dev/pts rw,nosuid,noexec - devpts rw,gid=5,mode=620,ptmxmode=666
19 14 0:16 / /run rw,nosuid,nodev - tmpfs tmpfs rw,size=206124k,mode=755
20 19 0:17 / /run/shm rw,nosuid,nodev,noexec - tmpfs tmpfs rw,size=515312k
[...]

$ mountpoint /sys
 /sys is not a mountpoint

(Uuuh... you're wrong)

2) This didn't work:

2017-01-13 10:01 GMT-03:00 Jonathan de Boyne Pollard:
>
>> Guillermo:
>>
>>> 2017-01-13 6:00 GMT-03:00 Jonathan de Boyne Pollard :
>>>
>>> Does your kernel support version 2 cgroupfs?
>>
>> Nope, it's a 4.4-series kernel.
>
> I've wangled a later kernel out of Debian 8 backports. (-: I'm going to
> have to write v1 detection for you, then.

/sys/fs/cgroup shows up empty even though the kernel has cgroups v1
support compiled in. And the catch-all logger reports this:

$ tai64nlocal /run/system-manager/log/current
2017-01-19 21:36:21.771835085 system-manager: INFO: cg1: Not required
by this kernel.
2017-01-19 21:36:21.771907685 system-manager: INFO: sc1: Not required
by this kernel.
2017-01-19 21:36:21.771914950 system-manager: INFO: cg2: Not required
by this kernel.
2017-01-19 21:36:21.771919422 system-manager: INFO: sc2: Not required
by this kernel.
2017-01-19 21:36:21.771923829 system-manager: ERROR: symlink:
/dev/ptmx: File exists
2017-01-19 21:36:21.771928172 system-manager: INFO: system-control
(pid 61) started (init )
2017-01-19 21:36:21.771932710 system-manager: INFO: cyclog (pid 62) started
2017-01-19 21:36:21.771936745 system-manager: INFO: service-manager
(pid 63) started
2017-01-19 21:36:21.809549752 system-manager: INFO: system-control
(pid 61) ended status 0
2017-01-19 21:36:21.810503507 system-manager: INFO: system-control
(pid 64) started (start sysinit)
[...]

The lines about cg1 and sc1, the arrays of iovecs corresponding to
/sys/fs/cgroup (fstype=tmpfs) and /sys/fs/cgroup/systemd
(fstype=cgroup), shouldn't be there, since there is a 'cgroup' line in
/proc/filesystems that query_control_group_level() in
source/common-manager.cpp should have seen:

$ grep cgroup /proc/filesystems
nodev cgroup

I couldn't figure this one out yet; I'll do more testing during the weekend.

G.
Received on Fri Jan 20 2017 - 23:37:08 UTC