Ticket #9261 (closed Bug Report - Hang/Deadlock: Need more Info)
Opened 3 years ago
Last modified 9 months ago
[HANG] Mythbackend hangs after upgrade to 0.24-fixes when try to start recording
| Reported by: | ernst.reiter@… | Owned by: | stuartm |
|---|---|---|---|
| Priority: | critical | Milestone: | 0.26 |
| Component: | MythTV - EIT | Version: | 0.24-fixes |
| Severity: | low | Keywords: | |
| Cc: | Ticket locked: | no |
Description
After the upgrade to 0.24 when tring to start a recording, mythbackend stops responding. Backtrace and log is attached.
Attachments
Change History
comment:2 Changed 2 years ago by danielk
- Owner danielk deleted
- Priority changed from major to minor
- Status changed from assigned to new
- Component changed from MythTV - Recording to MythTV - EIT
- Severity changed from medium to low
This appears to be caused by a dead lock in the EIT shutdown code.
comment:3 Changed 2 years ago by kenni
- Owner set to stuarta
- Status changed from new to assigned
- Milestone set to unknown
comment:4 Changed 2 years ago by jrauti@…
I have same problem with my system and I can see same deadlock with EITScanner::lock on my gdb backtrace. Is it possible that EITScanner::RunEventLoop?() manages to monopolise lock so that EITScanner::StopPassiveScan? can't get lock? This link http://stackoverflow.com/questions/2121200/qmutex-stuck-in-locked-state suggests that it is possible scenario. Most of the RunEventLoop?() runs with lock activated most it's time especially when activeScan==false. One fact that speaks also for this is that I can do controlled shutdown for backend in couple seconds so it's deadlock that can be resolved. Could solution be that RunEventLoop?() is chanced so that it does sched_yield (or sleeps) when activeScan==false?
comment:5 Changed 2 years ago by beirdo
- Summary changed from Mythbackend hangs after upgrade to 0.24-fixes when try to start recording to [HANG] Mythbackend hangs after upgrade to 0.24-fixes when try to start recording
comment:7 Changed 15 months ago by stuartm
- Owner changed from stuarta to stuartm
- Priority changed from minor to critical
- Type changed from Bug Report to Bug Report - Hang/Deadlock
- Status changed from assigned to accepted
- Milestone changed from unknown to 0.25
I'll take this, although I might be asking for input from Stuart A or Daniel
comment:8 Changed 14 months ago by beirdo
- Status changed from accepted to infoneeded
Is this repeatable with 0.25-rc? If not, let's close this as it is a report against a fairly old version of 0.24, and we have made a year's worth of changes since.
comment:11 Changed 9 months ago by stuartm
- Status changed from infoneeded to closed
- Resolution set to Need more Info
