Re: [PATCH v3 hmm 03/12] mm/hmm: Hold a mmgrab from hmm to mm

2019-06-16 Thread Christoph Hellwig
Looks good, Reviewed-by: Christoph Hellwig ___ amd-gfx mailing list amd-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/amd-gfx

[PATCH v3 hmm 03/12] mm/hmm: Hold a mmgrab from hmm to mm

2019-06-14 Thread Jason Gunthorpe
From: Jason Gunthorpe So long as a struct hmm pointer exists, so should the struct mm it is linked too. Hold the mmgrab() as soon as a hmm is created, and mmdrop() it once the hmm refcount goes to zero. Since mmdrop() (ie a 0 kref on struct mm) is now impossible with a !NULL mm->hmm delete the h