On 2023/04/16 1:13, Chuck Lever III wrote: >> On Apr 15, 2023, at 7:07 AM, Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> wrote: >> >> Since GFP_KERNEL is GFP_NOFS | __GFP_FS, usage like GFP_KERNEL | GFP_NOFS >> does not make sense. Drop __GFP_FS flag in order to avoid deadlock. > > The server side threads run in process context. GFP_KERNEL > is safe to use here -- as Jeff said, this code is not in > the server's reclaim path. Plenty of other call sites in > the NFS server code use GFP_KERNEL. GFP_KERNEL memory allocation calls filesystem's shrinker functions because of __GFP_FS flag. My understanding is Whether this code is in memory reclaim path or not is irrelevant. Whether memory reclaim path might hold lock or not is relevant. . Therefore, question is, does nfsd hold i_rwsem during memory reclaim path? > > But I agree that the flag combination doesn't make sense. > Maybe drop GFP_NOFS instead and call it only a clean-up?
