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RE: [Xen-devel] how to read value from xenstore inside kernel



> When I am using
>   char * test;
>   const char *nodename = "vif/2/0";
>   test = xenbus_read(XBT_NIL, nodename, "mac", NULL);
> 
> in netback .c ,I am getting this error when the kernel is rebooted.
> 
> guest1 BUG: scheduling while atomic: xenwatch/0x00000100/13
> 

That will be because the xenbus_read involves a wait of some sort, and
you can't do that in that sort of function.

Basically the rx and tx and other hardware event handlers need to
execute as fast as possible, which precludes any waiting for xenbus
responses to arrive.

Read your value at startup, or put a watch in at startup and read it
when it changes.

James

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