Messages in this thread | | | Date | Wed, 31 Mar 2010 14:05:00 -0700 | From | "H. Peter Anvin" <> | Subject | Re: start_kernel(): bug: interrupts were enabled early |
| |
On 03/31/2010 02:01 PM, Matthew Wilcox wrote: > On Wed, Mar 31, 2010 at 01:47:23PM -0700, Yinghai Lu wrote: >>>>> This appears to be caused by: >>>>> >>>>> start_kernel -> radix_tree_init -> kmem_cache_create (slub) -> >>>>> down_write -> __down_write (lib/rwsem-spinlock.c) -> spin_unlock_irq >>>>> >>> That's going to be hard to fix. >>> >> spin_unlock_irq from arm is different from other archs? > > Not all arches use lib/rwsem-spinlock.c. In particular, x86 doesn't > when X86_XADD is set. >
What I note is that lib/rwsem-spinlock.c seems to be rather inconsistent in its use of spin_lock_irqsave/spin_lock_irqrestore versus spin_lock_irq/spin_unlock_irq... in fact, __down_read is the *only* place where we use the latter as opposed to the former.
Is that a bug? If so, it would certainly explain this behavior.
-hpa
| |