| |
| If the box freezes hard with bttv ... |
| ===================================== |
| |
| It might be a bttv driver bug. It also might be bad hardware. It also |
| might be something else ... |
| |
| Just mailing me "bttv freezes" isn't going to help much. This README |
| has a few hints how you can help to pin down the problem. |
| |
| |
| bttv bugs |
| --------- |
| |
| If some version works and another doesn't it is likely to be a driver |
| bug. It is very helpful if you can tell where exactly it broke |
| (i.e. the last working and the first broken version). |
| |
| With a hard freeze you probably doesn't find anything in the logfiles. |
| The only way to capture any kernel messages is to hook up a serial |
| console and let some terminal application log the messages. /me uses |
| screen. See Documentation/serial-console.txt for details on setting |
| up a serial console. |
| |
| Read Documentation/oops-tracing.txt to learn how to get any useful |
| information out of a register+stack dump printed by the kernel on |
| protection faults (so-called "kernel oops"). |
| |
| If you run into some kind of deadlock, you can try to dump a call trace |
| for each process using sysrq-t (see Documentation/sysrq.txt). |
| This way it is possible to figure where *exactly* some process in "D" |
| state is stuck. |
| |
| I've seen reports that bttv 0.7.x crashes whereas 0.8.x works rock solid |
| for some people. Thus probably a small buglet left somewhere in bttv |
| 0.7.x. I have no idea where exactly, it works stable for me and a lot of |
| other people. But in case you have problems with the 0.7.x versions you |
| can give 0.8.x a try ... |
| |
| |
| hardware bugs |
| ------------- |
| |
| Some hardware can't deal with PCI-PCI transfers (i.e. grabber => vga). |
| Sometimes problems show up with bttv just because of the high load on |
| the PCI bus. The bt848/878 chips have a few workarounds for known |
| incompatibilities, see README.quirks. |
| |
| Some folks report that increasing the pci latency helps too, |
| althrought I'm not sure whenever this really fixes the problems or |
| only makes it less likely to happen. Both bttv and btaudio have a |
| insmod option to set the PCI latency of the device. |
| |
| Some mainboard have problems to deal correctly with multiple devices |
| doing DMA at the same time. bttv + ide seems to cause this sometimes, |
| if this is the case you likely see freezes only with video and hard disk |
| access at the same time. Updating the IDE driver to get the latest and |
| greatest workarounds for hardware bugs might fix these problems. |
| |
| |
| other |
| ----- |
| |
| If you use some binary-only yunk (like nvidia module) try to reproduce |
| the problem without. |
| |
| IRQ sharing is known to cause problems in some cases. It works just |
| fine in theory and many configurations. Neverless it might be worth a |
| try to shuffle around the PCI cards to give bttv another IRQ or make |
| it share the IRQ with some other piece of hardware. IRQ sharing with |
| VGA cards seems to cause trouble sometimes. I've also seen funny |
| effects with bttv sharing the IRQ with the ACPI bridge (and |
| apci-enabled kernel). |
| |
