snap htop doesnt show processes

[Oliver Leitner]

the snap package of "htop" shows no procresslist after installing it.

does it only work for other snap "apps" or does it work for the whole system?

[Jamie Strandboge (jdstrand)]

Thank you for reporting a bug.

Did you connect the 'system-observe' interface? Eg:

sudo snap connect htop:system-observe ubuntu-core:system-observe

If after doing this it still does not work, can you attach the output of 'grep audit /var/log/syslog' and indicate the architecture of the system that has the problem?

[Oliver Leitner (shadow333)]

hi jamie,

running your command outputs the following:

error: cannot perform the following tasks:
- Connect htop:system-observe to ubuntu-core:system-observe (cannot connect plug "system-observe" from snap "htop", no such plug)

output from syslog shows multiple collitions with apparmor:

[177602.095032] audit: type=1400 audit(1463692021.910:28304): apparmor="STATUS" operation="profile_load" name="snap.tmux.tmux" pid=8814 comm="apparmor_parser"
[177614.634377] audit: type=1400 audit(1463692034.450:28305): apparmor="DENIED" operation="open" profile="snap.tmux.tmux" name="/home/myuser/" pid=8847 comm="tmux" requested_mask="r" denied_mask="r" fsuid=1000 ouid=1000
[177614.634486] audit: type=1400 audit(1463692034.450:28306): apparmor="DENIED" operation="open" profile="snap.tmux.tmux" name="/" pid=8847 comm="tmux" requested_mask="r" denied_mask="r" fsuid=1000 ouid=0

cpu: Intel(R) Core(TM)2 Duo CPU T5870 @ 2.00GHz
uname: Linux lappy 4.6.0-999-lowlatency #201605152200 SMP PREEMPT Mon May 16 02:06:03 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
snapd version: 2.0.3

[Jamie Strandboge (jdstrand)]

I forgot to mention that your snap needs to specify 'plugs: [ system-observe ]'. Eg:

...
apps:
  htop:
    ...
    plugs: [ system-observe ]

Once you do that, the snap connect command should work.

As for the apparmor logs, the first is not a denial, it is indicating that the tmux profile was loaded. The next two indicate a denial with tmux which IIRC you filed elsewhere. Log entries you would be interested in would be for 'snap.htop....'.

[Oliver Leitner (shadow333)]

hi jamie, thanks for the answer,

ahhh, ok, i thouhgt snaps where ment to replace apt, and as such worked out of the box without me needing to edit any config.

i guess ill stay with the apt htop then for now.

[Jamie Strandboge (jdstrand)]

I'm slightly confused-- if you are just a user of the htop snap, then it sounds like there is a bug in the snap packaging for htop since it isn't requesting the system-observe plug. If you are the developer of the htop snap, simply adjust your packaging as mentioned then the snap connect command will work.

[Oliver Leitner (shadow333)]

im just a user, indeed.

[Oliver Leitner (shadow333)]

uhhhmz, thats also the reason i file a bug report rather than fixing it;-)

[Jamie Strandboge (jdstrand)]

Ok, thanks for the info. Since this bug is in the packaging of an individual snap, I'm going to close this bug. The snap has a 'mailto' support url and through that I see who the person is and will point him to this bug.

[Jamie Strandboge (jdstrand)]

Reopening after talking to maxiberta. As it happens, htop doesn't work with system-observe and system-observe needs a few additional accesses.

[Jamie Strandboge (jdstrand)]

This are the missing accesses:
@{PROC}/*/task/ r,
@{PROC}/*/task/*/stat r,
@{PROC}/*/task/*/statm r,
@{PROC}/*/task/*/cmdline r,

I'll get this fixed in snapd.

[Jamie Strandboge (jdstrand)]

This will be fixed in 2.0.6.

[Brian Murray (brian-murray)]

Hello Oliver, or anyone else affected,

Accepted snapd into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/snapd/2.0.6 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Maximiliano Bertacchini (maxiberta)]

htop is now working as expected with snapd 2.0.6.

[Brian Murray (brian-murray)]

Hello Oliver, or anyone else affected,

Accepted snapd into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/snapd/2.0.7 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Jamie Strandboge (jdstrand)]

The htop package in the store does not specify "plugs: [ system-observe ]" in its yaml so I had to fetch it, unsquash it, adjust meta/snap.yaml to have plugs, snapcraft snap ./squashfs-root, then install to test. After doing that I can do 'sudo snap connect htop:system-observe ubuntu-core:system-observe' and verify this bug: htop now shows the process list.

[Maximiliano Bertacchini (maxiberta)]

It actually works without "system-observe", but only shows processes owned by the current user. Just realized "system-observe" enables htop to show all other processes. I'm fixing that asap. Thanks!

[Mark Shuttleworth (sabdfl)]

I just learned from this bugreport about the htop snap. Thanks!

Mark

[Oliver Leitner (shadow333)]

well, except for the little glitch that Maximiliano mentoined, it seems to work now... looking forward for your fix, Maxiberta. thanks for the support guys.

[Federico Gimenez (fgimenez)]

Verified with latest proposed:

fgimenez@fgimenez-Standard-PC-i440FX-PIIX-1996:~$ apt-cache policy snapd
snapd:
  Installed: 2.0.8
  Candidate: 2.0.8
  Version table:
 *** 2.0.8 500
        500 http://archive.ubuntu.com/ubuntu xenial-proposed/main amd64 Packages
        100 /var/lib/dpkg/status
     2.0.5 500
        500 http://es.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages
     2.0.2 500
        500 http://es.archive.ubuntu.com/ubuntu xenial/main amd64 Packages
fgimenez@fgimenez-Standard-PC-i440FX-PIIX-1996:~$ sudo snap install htop
228.00 KB / 228.00 KB [===========================================================================================================================] 100.00 % 431.02 KB/s

Name Version Rev Developer Notes
htop 2.0.1 16 maxiberta -

fgimenez@fgimenez-Standard-PC-i440FX-PIIX-1996:~$ htop

[... shows processes ...]

[Launchpad Janitor (janitor)]

This bug was fixed in the package snapd - 2.0.8

---------------
snapd (2.0.8) xenial; urgency=medium

  * New upstream release: LP: #1589534
    - debian: make `snap refresh` times more random (LP: #1537793)
    - cmd: ExecInCoreSnap looks in "core" snap first, and only in
      "ubuntu-core" snap if rev>125.
    - cmd/snap: have 'snap list' display helper message on stderr
      (LP: #1587445)
    - snap: make app names more restrictive.

 -- Michael Vogt <email address hidden> Wed, 08 Jun 2016 07:56:58 +0200

[Launchpad Janitor (janitor)]

This bug was fixed in the package snapd - 2.11+16.10

---------------
snapd (2.11+16.10) yakkety; urgency=medium

  * New upstream release: LP: #1605303
    - increase version number to reflect the nature of the update
      better
    - store, daemon, client, cmd/snap, docs/rest.md: adieu search
      grammar
    - debian: move snapd.refresh.timer into timers.target
    - snapstate: add daemon-reload to fix autopkgtest on yakkety
    - Interfaces: hardware-observe
    - snap: rework the output after a snap operation
    - daemon, cmd/snap: refresh --devmode
    - store, daemon, client, cmd/snap: implement `snap find --private`
    - tests: add network-observe interface spread test
    - interfaces/builtin: allow getsockopt for connected x11 plugs
    - osutil: check for nogrup instead of adm
    - store: small cleanups (more needed)
    - snap/squashfs: fix test not to hardcode snap size
    - client,cmd/snap: cleanup cmd/snap test suite, add extra args
      testThis cleans up the cmd/snap test suite:
    - wrappers: map "never" restart condition to "no."
    - wrappers: run update-desktop-database after add/remove of desktop
      files
    - release: work around elementary mistake
    - many: remove all traces of channel from the buying codepath
    - store: kill setUbuntuStoreHeaders
    - docs: add payment methods documentation
    - many: present user with a choice of payment backends
    - asserts: add cross checks for snap asserts
    - cmd/snap,cmd/snap-exec: support running hooks via snap-exec.
    - tests: improve snap run symlink tests
    - tests: add content sharing interface spread test
    - store & many: a mechanical branch shortening store names
    - snappy: remove old snappy pkg
    - overlord/snapstate: kill flagscompat
    - overlord/snapstate, daemon, client, cmd/snap: devmode override
      (aka confined)
    - tests: extend refresh test to talk to the staging and production
      stores
    - asserts,daemon: cross checks for account and account-key
      assertions
    - client: existing JSON fixtures uses tabs for indentation
    - snap-exec: add proper integration test for snap-exec
    - spread.yaml, tests: replace hello-world with test-snapd-tools
    - tests: add locale-control interface spread test
    - tests: add mount-observe interface spread test
    - tests: add system-observe interface spread test
    - many: add AuthContext to mediate user updates to the state
    - store/auth: add helper for the macaroon refresh endpoint
    - cmd: add buy command
    - overlord: switch snapstate.Update to use ListRefresh (aka
      /snaps/metadata)
    - snap-exec: fix silly off-by-one error
    - tests: stop using hello-world.echo in the tests
    - tests: add env command to test-snapd-tools
    - classic: remove (most of) "classic" mode, this is implemented as a
      snap now
    - many: remove snapstate.Candidate and other cleanups
    - many: removed authenticator, store gets a user instead
    - asserts: fix minor doc comment typo
    - snap: ensure unknown arguments to `snap run` are ignored
    - overlord/auth: add Device/SetDevice to persist device identity in
      state
    - overlord: make SyncBoot work aga...