On Fri, Mar 12, 2021 at 01:58:44PM -0700, Alex Williamson wrote: > Yeah, we can indeed use memalloc_nofs_save/restore(). It seems we're > trying to allocate something for pfnmap tracking and that enables lots > of lockdep specific tests. Is it valid to wrap io_remap_pfn_range() > around clearing this flag or am I just masking a bug? Thanks, Yes, I think it is fine. Those functions are ment to be used in a no-fs kind of region exactly like this. no-fs is telling the allocator not to do reclaim which is forbidden under the locks here (as reclaim will also attempt to get these locks) I would defer to Michal Hocko though, maybe cc him on the final patch series version. Jason
