Bug 1382335

This heppens to me too:

.........
 2662 ?        Ss     0:00 gpg-agent --homedir /var/cache/PackageKit/25/metadata/updates.tmp/gpgdir --use-standard-socket --daemon
 2843 ?        Ss     0:00 gpg-agent --homedir /var/cache/PackageKit/25/metadata/zyga-snapcore.tmp/gpgdir --use-standard-socket --da
[eRadical@me ~]$ sudo strace -p 2843
strace: Process 2843 attached
pselect6(4, [3], NULL, NULL, {tv_sec=1, tv_nsec=606607385}, {[], 8}) = 0 (Timeout)
pselect6(4, [3], NULL, NULL, {tv_sec=2, tv_nsec=1014}, {[], 8}) = 0 (Timeout)
clone(child_stack=0x7ff5470bcff0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, parent_tidptr=0x7ff5470bd9d0, tls=0x7ff5470bd700, child_tidptr=0x7ff5470bd9d0) = 3916
futex(0x7ff547ab8060, FUTEX_WAKE_PRIVATE, 1) = 1
pselect6(4, [3], NULL, NULL, {tv_sec=2, tv_nsec=91591}, {[], 8}) = 1 (in [3], left {tv_sec=2, tv_nsec=89314})
accept(3, {sa_family=AF_UNIX}, [110->2]) = 5
clone(child_stack=0x7ff5468bbff0, flags=CLONE_VM|CLONE_FS|CLONE_FILES|CLONE_SIGHAND|CLONE_THREAD|CLONE_SYSVSEM|CLONE_SETTLS|CLONE_PARENT_SETTID|CLONE_CHILD_CLEARTID, parent_tidptr=0x7ff5468bc9d0, tls=0x7ff5468bc700, child_tidptr=0x7ff5468bc9d0) = 3917
futex(0x7ff547ab8060, FUTEX_WAKE_PRIVATE, 1) = 1
pselect6(4, [3], NULL, NULL, {tv_sec=1, tv_nsec=999802436}, {[], 8}) = 0 (Timeout)
pselect6(4, [3], NULL, NULL, {tv_sec=2, tv_nsec=926}, {[], 8}) = 0 (Timeout)
pselect6(4, [3], NULL, NULL, {tv_sec=2, tv_nsec=747}, {[], 8}) = 0 (Timeout)
pselect6(4, [3], NULL, NULL, {tv_sec=2, tv_nsec=570}, {[], 8}) = 0 (Timeout)
pselect6(4, [3], NULL, NULL, {tv_sec=2, tv_nsec=673}, {[], 8}^Cstrace: Process 2843 detached
 <detached ...>

PackageKit.x86_64 1.1.4-2.fc25

We hit this composing branched Fedora https://pagure.io/fedora-kickstarts/c/1c70356e936a8535ebd94d02a5cf3370b410f5df?branch=f26 is the workaround we had to do to get livecds working again PackageKit has to ensure it cleans up gpg-agent after itself

On Fedora 26, this issue also affects dnf, which shares just a few libraries (librepo, libsolv) with PackageKit. As strace reveals, the `gpg-agent` processes are started from gpg2, running with this command line:
> execve("/usr/bin/gpg2", ["gpg2", "--enable-special-filenames", "--batch", "--no-sk-comments", "--status-fd", "38", "--no-tty", "--charset", "utf8", "--enable-progress-filter", "--exit-on-status-write-error", "--import", "--", "-&39"], [/* 25 vars */] <unfinished ...>

which, in turn, starts gpg-agent:

> execve("/usr/bin/gpg-agent", ["gpg-agent", "--homedir", "/tmp/tmpc5mct44v", "--use-standard-socket", "--daemon"], [/* 25 vars */]) = 0

So it looks like the issue is actually in gpg2, not PackageKit. Reassinging then.

Steps to reproduce for dnf:
1. run `dnf upgrade`
2. after dnf finished, have a look at the list of running processes.

Steps to reproduce for gnome-software (using PackageKit):
1. open gnome-software
2. on "Updates" page, press the refresh button
3. exit gnome-software
4. have a look at the list of running processes.

Steps to reproduce for pkcon (the PackageKit command line utility):
1. run $ pkcon --cache-age=10 get-updates
2. after pkcon finished, have a look at the list of running processes.

What happens:
A list of gpg-agent processes is still running and gets more and more on every of the "Steps to reproduce" options above. Those processes are never terminated, even though they finished their work.

I do not see any ways around it than killing the gpg-agent from the process that runs the gpg with the different homedir. The gpg-agent is kept running by gpg because it would be used for subsequent gpg runs with the same homedir. If the homedir is just temporary and there won't be any subsequent gpg runs the gpg-agent must be explicitly killed.

The agent can be killed with:

gpgconf --kill gpg-agent

This message is a reminder that Fedora 26 is nearing its end of life.
Approximately 4 (four) weeks from now Fedora will stop maintaining
and issuing updates for Fedora 26. It is Fedora's policy to close all
bug reports from releases that are no longer maintained. At that time
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able to fix it before Fedora 26 is end of life. If you would still like
to see this bug fixed and are able to reproduce it against a later version
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version prior this bug is closed as described in the policy above.

Although we aim to fix as many bugs as possible during every release's
lifetime, sometimes those efforts are overtaken by events. Often a
more recent Fedora release includes newer upstream software that fixes
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This issue is not present any more on Fedora 28.