Bug 406460

Summary:	Dolphin freezes or crashes when opening a mounted cifs share over slow VPN
Product:	[Applications] dolphin	Reporter:	Christian Schütze <schuetze.christian24>
Component:	general	Assignee:	Dolphin Bug Assignee <dolphin-bugs-null>
Status:	RESOLVED WORKSFORME
Severity:	crash	CC:	elvis.angelaccio, kde, nate
Priority:	NOR
Version First Reported In:	18.12.3
Target Milestone:	---
Platform:	openSUSE
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Christian Schütze 2019-04-12 09:02:33 UTC

I'm using a mounted cifs share of my NAS and sometimes if I'm working remotely (via VPN) using the share will freeze or crash dolphin. Using LAN is totally fine and everything works as expected. Also if working remotely a standard smb:// access is also working fine (if the connection is slow, it might show an empty folder for some time before showing the contents, but it stays responsive). However using the same share via mounted cifs share dolphin starts freezing and suddenly also crashes as the connection is slow.

STEPS TO REPRODUCE
1. Mount a network cifs share (in my case freenas)
2. Connect to external network (in the best case for this to happen - a slow one)
3. Connect to VPN
4. Access share (Open folders, quickly going up and down in the folder structure)

OBSERVED RESULT
Dolphin is fetching the folders contents (while it fetches these the folder is empty) and then starts freezing if I'm switching folders (most probably because it fetches the subdirectory sizes) and might also crash after a short time of unresponsiveness.

EXPECTED RESULT
Dolphin should never freeze or crash while accessing a mounted cifs share remotely via VPN. Longer loading times should be indicated not by an empty folder but a loading bar somewhere (maybe reuse of free space bar in the bottom right like then access is done via smb://)

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: openSUSE Tumbleweed 20190408
KDE Plasma Version: 5.15.4
KDE Frameworks Version: 5.56.0
Qt Version: 5.12.2

ADDITIONAL INFORMATION
This might not happen if the folders are small and contain only a few items or the connection is good.

Comment 1 Elvis Angelaccio 2019-04-13 09:12:29 UTC

Can you provide a stacktrace of the crash?

Comment 2 Kai Uwe Broulik 2019-04-15 07:10:21 UTC

Freezing is to be expected since this is CIFS and mount APIs are all synchronous, that's why you should be using the smb:// URLs. However, it should never crash, please provide a backtrace.

Comment 3 Christian Schütze 2019-04-15 07:31:38 UTC

Unfortunately I cannot get it to crash again.
It only freezes for a more or less unlimited time until I have to terminate the process.

Comment 4 Kai Uwe Broulik 2019-04-15 08:40:02 UTC

Can you gdb and see where it freezes? Also, can you observe in system mointor (ctrl+Esc) if it is stuck in "Disk sleep", then it's uninterruptible and we cannot really do anything about it.

Comment 5 Christian Schütze 2019-04-26 08:37:34 UTC

I can confirm it is in the state "disk sleep". Is there a way to get around this? Because most of the time even terminating the windows does not work (I can click Terminate but the window wont terminate and stay frozen). It even more gets a problem as I use the start menu tabs computer/history which will also freeze in this scenario which can go further, affect more applications and then only can be "resolved" by rebooting.

Comment 6 Kai Uwe Broulik 2019-04-26 09:16:26 UTC

> Is there a way around this?

Using smb:// instead of cifs.

Comment 7 Bug Janitor Service 2019-05-11 04:33:09 UTC

Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

If you have already provided the requested information, please
mark the bug as REPORTED so that the KDE team knows that the bug is
ready to be confirmed.

Thank you for helping us make KDE software even better for everyone!

Comment 8 Bug Janitor Service 2019-05-26 04:33:09 UTC

This bug has been in NEEDSINFO status with no change for at least
30 days. The bug is now closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

Thank you for helping us make KDE software even better for everyone!