On Wed, Jun 10, 2015 at 9:11 AM, Christoph Hellwig <hch@xxxxxx> wrote: > On Wed, Jun 10, 2015 at 08:36:48AM -0700, Dan Williams wrote: >> On surprise removal my expectation is that the driver keeps the the >> ioremap mapping alive for at least a synchronize_rcu() period. With >> that in place the rcu_read_lock() in kmap_atomic_pfn_t() should keep >> the mapping alive for the short duration, or otherwise prevent new >> mappings. However, I missed converting the driver to order its >> iounmap() with respect to the pfn range registration via devres, will >> fix. > > Right. I guess the best idea is to replace devm_register_kmap_pfn_range > with an interface that does the ioremap, in which case the cleanup > function can take care of the proper ordering behind the drivers back. Even better than what I was thinking... will do. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
