When playing audio with the snd-powermac driver on a PowerMac G4 Quicksilver (Tumbler audio) the sound hangs after a few seconds.
- The time before a hang varies from one second to one minute. - Killing the process playing sound and starting again will allow sound to continue (for a few more seconds). - Many different userspace audio systems and different audio sources all encounter this bug--definitely a kernel issue. - Vanilla kernels from 2.6.20 up to git HEAD show this behavior. Others have reported this bug on distro kernels.[1][2] I used git-bisect to find that the regression first occured after git commit 68a64357d15ae4f596e92715719071952006e83c "powerpc: Merge 32 and 64 bits asm-powerpc/io.h" by benh.[3] My kernel debugging skills are admittedly limited, but I scattered printks through some relevant files and found that audio stops just as snd_pmac_pcm_update in sound/ppc/pmac.c encounters a struct dbdma_cmd with xfer_status == 0x8088. Normally it should be 0x84 (ie: ACTIVE | RUN) or 0x0. Hopefully this means something to somebody. I'm willing to do more debugging if more information is necessary, kindly CC me on replies to this message. Thank you for your time, Dave Vasilevsky [1] https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.20/+bug/87652 [2] http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=436723 [3] http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=68a64357d15ae4f596e92715719071952006e83c - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
