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Re: NetBSD xen dom0 kernel panic

On Wed, Mar 18, 2009 at 09:24:26PM -0400, peter wrote:
> On Wed, 2009-03-18 at 18:59 -0400, Thor Lancelot Simon wrote:
> > On Wed, Mar 18, 2009 at 03:20:11PM -0400, Peter wrote:
> > > 
> > > In what way is using pool_foo safe in an interrupt context?
> > 
> > In the way the manual page says: if the pool is initialized with the
> > highest IPL in effect in any interrupt context in which it will be accessed,
> > and all accesses to the pool are protected against interrupts at that IPL
> > or lower.
> And the malloc and free calls aren't an issue?

Uh, what malloc and free calls, the ones that pool(9) doesn't make?

There is one call to malloc in subr_pool.c, to allocate a tracing
structure if POOL_DIAGNOSTIC is defined -- and that's in pool_init(),
which only a madman would call from interrupt context.

The manual page says what you have to do to use pool(9) safely
from interrupt context.  Obey it and the code will work fine.


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