On Tue, Jul 23, 2019 at 01:07:00PM -0400, Jeff Layton wrote: > Note that those places are already broken. AIUI, the basic issue is that > vmalloc/vfree have to fix up page tables and that requires being able to > sleep. This patch just makes this situation more evident. If that patch > gets merged, I imagine we'll have a lot of places to clean up (not just > in xfs). > > Anyway, in the case of being in an interrupt, we currently queue the > freeing to a workqueue. Al mentioned that we could create a new > kvfree_atomic that we could use from atomic contexts like this. That may > be another option (though Carlos' patch looked reasonable to me and > would probably be more efficient). The point is for XFS we generally only use kmem_free for pure kmalloc allocations under spinlocks. But yes, the interfac is a little suboptimal and a kmem_free_large would be nicer and then warnings like this that might be pretty useful could be added.
