# kexec and sound

## JoHo42

Hi people 

i have test kexec, with the kernerl version 2.6.31-gentoo-r6 and kexec version 2.0.0-r1.

If i reboot the computer with kexec everything works fine, but my soundcard is lost.

If i start some soundcard tools (alsamixer) the tools says soundcard is in use by an

other application.

mfg Joerg

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## aCOSwt

If I correctly recall, kexec is confusing some IRQs. (especially shared ones)

As this confusion sounds to me fairly theoritically "normal", I would tend to say that I do not see much solutions for this apart trying software interrupts, this, providing your device is msi capable.Last edited by aCOSwt on Thu Feb 11, 2010 8:02 am; edited 1 time in total

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## JoHo42

Hi aCOSwt,

cool name.

What is the meaning of msi?

What is msi?

So i can forgot the kexec system?

mfg joerg

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## aCOSwt

Well, MSI stands for Message Signalled Interrupts

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=blob;f=Documentation/PCI/MSI-HOWTO.txt;hb=HEAD

I was suggesting this, not in replacement of kexec but as some theoritical mean to overcome kexec's messing on shared IRQ's.

Theoritical because I never tried.

Here is some interesting thread about IRQ troubles with kexec :

http://lkml.indiana.edu/hypermail/linux/kernel/0503.0/2457.html

Another possible way to investigate would be to make so you do not get any shared IRQ on your system.

Good luck !

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## JoHo42

Hi aCOSwt,

i have test it with msi options, but the problem is the same.

Now i wait for the next kernel and test it again.

mfg Joerg

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## aCOSwt

Can you make so your sound card does not share its IRQ with something else.

If you cannot, can you make so it does not share its IRQ with another device potentially particularily busy.

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