[alsa-devel] Bad page state in process 'rmmod' cs4281

["Timo T.Hyrsylä"]

Trying to make Alsa work on our embedded arm system with ixdp425 and CS4281.

kernel is 2.6.20.3 and the Alsas (driver+lib+utils) latest 1.0.19

Other than the two below errors, the system seems to work ok.

When removing the snd_cs4281 module, dmesg reports multiple errors about 
bad page

<0>Bad page state in process 'rmmod'
<0>page:c4007300 flags:0x00004000 mapping:00000000 mapcount:0 count:0
<0>Trying to fix it up, but a reboot is needed
<0>Backtrace:
<0>Bad page state in process 'rmmod'
<0>page:c4007320 flags:0x00004000 mapping:00000000 mapcount:0 count:0
<0>Trying to fix it up, but a reboot is needed
<0>Backtrace:

I've managed to track down the error upto dma_free_coherent.

snd_pcm_free > snd_pcm_lib_preallocate_free_for_all > 
snd_pcm_lib_preallocate_free > snd_pcm_lib_preallocate_dma_free > 
snd_dma_free_pages > snd_free_dev_pages > dma_free_coherent


Another issue, possibly related, is that when running aplay with --mmap 
it will crash with:

Internal error: Oops: f3 [#1]
PC is at snd_pcm_mmap_data_nopage+0x10c/0x148 [snd_pcm]
LR is at __handle_mm_fault+0x16c/0x8ac



any helping ideas?



-- 
Timo TH.