I am using Dovecot 2.2.36 and I am trying to use doveadm backup to migrate email from Gmail to Dovecot. When I run doveadm backup, it goes for a while and then eventually hits an assertion error (I've tried this a few times now and it happens reliably). The assertion failure looks like this: dsync(evan at eklitzke.org): Panic: file imapc-client.c: line 179 (imapc_client_run_pre): assertion failed: (client->ioloop == NULL) The last few lines of log output before the crash look like this: https://gist.github.com/eklitzke/9a0dd77c44a6ee33e812f85d5773c24c The GDB backtrace when the program panics looks like this: https://gist.github.com/eklitzke/6b311474b08b546c462e0444c5cf479b The output of "dovecot --version" prints "2.2.36 (1f10bfa63)" and I'm using the version provided by Fedora's dovecot-2.2.36-1.fc28.src.rpm package. Is there any other information I can provide to assist in debugging? I could provide a core dump provided there was a way to scrub my IMAP credentials. -- Evan Klitzke pgp: 0x157EFCACBC648422 e: evan at eklitzke.org w: https://eklitzke.org
"Reliably" means what exactly? - At progress of 66%? - after e.g. 9611 Mails? - whenever a specific Mail is touched? Von unterwegs gesendet> Am 27.09.2018 um 20:52 schrieb Evan Klitzke <evan at eklitzke.org>: > > I am using Dovecot 2.2.36 and I am trying to use doveadm backup to migrate email from Gmail to Dovecot. When I run doveadm backup, it goes for a while and then eventually hits an assertion error (I've tried this a few times now and it happens reliably). > > The assertion failure looks like this: > > dsync(evan at eklitzke.org): Panic: file imapc-client.c: line 179 (imapc_client_run_pre): assertion failed: (client->ioloop == NULL) > > The last few lines of log output before the crash look like this: https://gist.github.com/eklitzke/9a0dd77c44a6ee33e812f85d5773c24c > > The GDB backtrace when the program panics looks like this: https://gist.github.com/eklitzke/6b311474b08b546c462e0444c5cf479b > > The output of "dovecot --version" prints "2.2.36 (1f10bfa63)" and I'm using the version provided by Fedora's dovecot-2.2.36-1.fc28.src.rpm package. > > Is there any other information I can provide to assist in debugging? I could provide a core dump provided there was a way to scrub my IMAP credentials. > > -- > Evan Klitzke pgp: 0x157EFCACBC648422 > e: evan at eklitzke.org w: https://eklitzke.org
Admin <admin at awib.it> writes:> "Reliably" means what exactly? > - At progress of 66%? > - after e.g. 9611 Mails? > - whenever a specific Mail is touched?Reliably means "before the sync finishes", but not at a specific point. I have about 2GB of mail I'm trying to sync, and the furthest the sync has gotten is about 1GB of the way in. I looked at the core dump some more and I sort of get what's going on, although I don't understand the code well enough to fix the issue. The imapc_client is being called in a re-entrant way, in the sense that imapc_client_run() is called, and then while that imapc_client_run() function is being invoked and is on the call stack, the event loop gets triggered again and calls imapc_connection_input(). That causes imapc_client_run() to be called with the same imapc_client object, and this is what causes the assertion to fail. You can see this in the stack trace I posted, and I was able to confirm in GDB that the two invocations of imapc_client_run_pre() on the call stack both refer to the same imapc_client struct. -- Evan Klitzke pgp: 0x157EFCACBC648422 e: evan at eklitzke.org w: https://eklitzke.org
> On 27 Sep 2018, at 21.52, Evan Klitzke <evan at eklitzke.org> wrote: > > I am using Dovecot 2.2.36 and I am trying to use doveadm backup to migrate email from Gmail to Dovecot. When I run doveadm backup, it goes for a while and then eventually hits an assertion error (I've tried this a few times now and it happens reliably). > > The assertion failure looks like this: > > dsync(evan at eklitzke.org): Panic: file imapc-client.c: line 179 (imapc_client_run_pre): assertion failed: (client->ioloop == NULL) > > The last few lines of log output before the crash look like this: https://gist.github.com/eklitzke/9a0dd77c44a6ee33e812f85d5773c24c > > The GDB backtrace when the program panics looks like this: https://gist.github.com/eklitzke/6b311474b08b546c462e0444c5cf479bLooks like it crashes when: - you have multiple folders - dsync takes over 1 second between folders - a new mail arrives during dsync - you have imapc_features=gmail-migration A simple workaround should be to comment out "list->refreshed_mailboxes_recently = FALSE" in imapc-sync.c. A better fix would probably be to remember an opened folder's mailbox_info_flags so it doesn't try to re-get them.