At Wed, 19 Mar 2008 21:12:51 +0100, Prakash Punnoor wrote:
Hi,
I didn't test an earlier 2.6.25-rc kernel, as I had no working nvidia driver... But the problem I am reporting happens before nvidia gets loaded.
With 2.6.24.3 the ALSA driver didn't made any troubles for me. Stock kernel and enable_msi=1 made the driver to get a timeout and go back to legacy IRQ.
With patches from http://kerneltrap.org/mailarchive/linux-kernel/2007/11/25/443612 2.6.24.x even works with MSI.
Now with above 2.6.25-rc kernel regardless of using above patch, the kernel _hangs_ now when trying to initialize ALSA. It is even so bad, that doing a hw reset and trying to load patched 2.6.24 kernel causes ALSA to hang when trying to enable MSI. I need to turn power off and then patched 2.6.24 with MSI works again.
2.6.25-rc with ALSA Intel HDA _not_ forcing enable_msi causes it to boot.
to summarize:
2.6.24 + patch + enable_msi=1: OK (and HDA MSI) 2.6.24 + enable_msi=1: OK (and HDA legacy IRQ) 2.6.24 + patch: OK (and HDA legacy IRQ) 2.6.24: OK (and HDA legacy IRQ)
2.6.25-rc + patch + enable_msi=1: hang 2.6.25-rc + enable_msi=1: hang 2.6.25-rc + patch: OK (and HDA legacy IRQ) 2.6.25-rc: OK (and HDA legacy IRQ)
I don't know whether something in Linux MSI support was changed having effect on ALSA or whether the HDA driver has a regression.
At least there is no big change regarding the IRQ handling in ALSA HD-audio driver since 2.6.24...
Takashi