QT WebEngine Render process crashing

[the_Pan]

Hi folks,

I also stumbled across this problem now, and I don't understand, why those 2 files (libicudata.so.67 & libiconv.so.2) get shown as "not found", while they are present in the directory, if I search there directly for them.
I downgraded the mesa driver without success, and didn't update the kernel.

[EbookDwarf]

After encountering this issue myself
and finding the same thing occuring:
calibre, version 5.38.0
ERROR: Render process crashed: The Qt WebEngine Render process has crashed. You should try restarting the viewer.

$ ldd /opt/calibre/lib/libQt5WebEngine.so.5 | grep found
libiconv.so.2 => not found
even though as can be seen, it definitely exists
$ ls /opt/calibre/lib/libiconv.so.2
/opt/calibre/lib/libiconv.so.2*

I did some digging, and found a workaround

QTWEBENGINE_DISABLE_SANDBOX=1 ebook-viewer
Allows the calibre ebook-viewer to launch and work sucessfully

Does this help in pinpointing the actual cause of the error (and an actual solution for it) ?

[the_Pan]

Originally Posted by EbookDwarf

...
I did some digging, and found a workaround

QTWEBENGINE_DISABLE_SANDBOX=1 ebook-viewer
Allows the calibre ebook-viewer to launch and work sucessfully...

Works, thank you for finding out!

if you start calibre with the disable sandbox command, the ebook viewer also works within calibre for me

[kovidgoyal]

If sandboxing is failing then the cause will most likely be a kernel or glibc update that changes some syscall that the Qt sandboxing infrastructure uses.

And libiconv is a red herring. calibre runs with LD_LIBRARY_PATH=/opt/calibre/lib so libiconv will load fine.

Some googling will find you various hits: https://bugs.launchpad.net/ubuntu/+s...c/+bug/1939993
https://forums.ankiweb.net/t/setting...-linux/13765/7

[EbookDwarf]

While yes, that is correct that it is caused by the changes in glibc with regard to secure computing (seccomp)
going forward more and more people will have the updated version of glibc

and so, using the workaround is only a bandaid solution

[kovidgoyal]

The fix for the glibc change is supposedly in Qt 6.2, which the calibre 6 betas use, already. Not to mention that some distros have reverted the glibc change.

[EbookDwarf]

Originally Posted by kovidgoyal

The fix for the glibc change is supposedly in Qt 6.2, which the calibre 6 betas use, already.

How does one get access to said calibre 6 betas?

Originally Posted by kovidgoyal

Not to mention that some distros have reverted the glibc change.

Which again, is only a temporary fix, as at some point, they too will eventually upgrade

[kovidgoyal]

Originally Posted by EbookDwarf

How does one get access to said calibre 6 betas?

There is a link to them in post #8 of this thread.

Which again, is only a temporary fix, as at some point, they too will eventually upgrade

Yes, and if you wish to keep using the calibre ebook-viewer from calibre 5 on these distros, you will need to stop upgrading them.

[EbookDwarf]

Originally Posted by kovidgoyal

which the calibre 6 betas use

Just tested with calibre6 beta (5.99.8) and it works like a charm!

Now to wait for the standard installer to be available for calibre6

[the_Pan]

Originally Posted by EbookDwarf

Now to wait for the standard installer to be available for calibre6

I just found the following command on Kovids calibre website:

sudo mkdir -p /opt/calibre && sudo rm -rf /opt/calibre/* && sudo tar xvf /path/to/downloaded/calibre-tarball.txz -C /opt/calibre && sudo /opt/calibre/calibre_postinstall

This way you can install the calibre beta like a "normal installation".
I'm on calibre-beta to now and can confirm, the viewer is working without disabling the sandbox.

Thank both of you kovidgoyal and EbookDwarf

[henriquemaia]

Originally Posted by EbookDwarf

I did some digging, and found a workaround

QTWEBENGINE_DISABLE_SANDBOX=1 ebook-viewer
Allows the calibre ebook-viewer to launch and work sucessfully.

Thanks! That did it. I like having Calibre's ebook reader ready for when I have to check epubs on my computer. Now the toolset is again complete.