Segfault with backup command

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Daren
Posts: 4
Joined: Thu Nov 12, 2020 9:39 am

Segfault with backup command

Post by Daren » Thu Nov 12, 2020 9:57 am

Trying to get a backup of my Fight Club Blu-Ray.
As far as I understood the backup functionality is supposed to work like the dvdbackup tool for DVDs, presreving directory structure with decrypted files.

Anyway, this segfaults for me on Linux:

Code: Select all

$ makemkvcon backup disc:/dev/sr0 FIGHT_CLUB
MakeMKV v1.15.3 linux(x64-release) started
Backing up disc into folder "file://FIGHT_CLUB"
[1]    12855 segmentation fault (core dumped)  makemkvcon backup disc:/dev/sr0 FIGHT_CLUB
Running this with gdb:

Code: Select all

$ gdb makemkvcon
(gdb) run backup disc:/dev/sr0 FIGHT_CLUB
Starting program: /usr/bin/makemkvcon backup disc:/dev/sr0 FIGHT_CLUB
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
[New Thread 0x7ffff3487640 (LWP 14903)]
[New Thread 0x7fffdeb3b640 (LWP 14904)]
MakeMKV v1.15.3 linux(x64-release) started
[New Thread 0x7fffdddc3640 (LWP 14905)]
Backing up disc into folder "file://FIGHT_CLUB"

Thread 2 "makemkvcon" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7ffff3487640 (LWP 14903)]
0x00000000007e7500 in ?? ()
(gdb) bt
#0  0x00000000007e7500 in ?? ()
#1  0x00000000007e0942 in ?? ()
#2  0x00000000006550c1 in ?? ()
#3  0x00000000006560a6 in ?? ()
#4  0x00007ffff7ea93e9 in start_thread () from /usr/lib/libpthread.so.0
#5  0x00007ffff7dd7293 in clone () from /usr/lib/libc.so.6
Remuxing to MKV with the CLI and GUI works though.

It would be nice to have a 1:1 decrypted copy of a Blu-Ray, hope this can be fixed.

If you need a core dump I can provide that as well.

Daren
Posts: 4
Joined: Thu Nov 12, 2020 9:39 am

Re: Segfault with backup command

Post by Daren » Thu Nov 12, 2020 11:51 am

I think I found the culprit.

First, I used the 'disc:' source wrong and 2nd, the backup command needs a '--decrypt' flag which I found in http://www.makemkv.com/developers/usage.txt

Code: Select all

$ makemkvcon --decrypt backup disc:0 FIGHT_CLUB
This segfaulted once too after it downloaded some "latest HK".
Ran it again and it's backing up now.

Guess it would be good if the previous command errors out with some helpful message.

Woodstock
Posts: 10311
Joined: Sun Jul 24, 2011 11:21 pm

Re: Segfault with backup command

Post by Woodstock » Thu Nov 12, 2020 2:14 pm

"Latest HK" is the latest HashKey list of decryption keys. It's important for UHD disks, less so for others.

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