On 13.11.2017 16:19, Janosch Frank wrote: > This is KVM, not qemu, subject s/x// > > > On 10.11.2017 16:18, David Hildenbrand wrote: >> gmap_mprotect_notify() refuses shadow gmaps. Turns out that >> a) gmap_protect_range() >> b) gmap_read_table() >> c) gmap_pte_op_walk() >> >> Are never called for gmap shadows. And never should be. This dates back >> to gmap shadow prototypes where we allowed to call mprotect_notify() on >> the gmap shadow (to get notified about the prefix pages getting removed). >> This is avoided by always getting notified about any change on the gmap >> shadow. >> >> The only real function for walking page tables on shadow gmaps is >> gmap_table_walk(). >> >> So, essentially, these functions should never get called and >> gmap_pte_op_walk() can be cleaned up. Add some checks to callers of >> gmap_pte_op_walk(). > > This already made sense when discussing, but I traced the callers anyhow > to make sure we didn't accidentally forget one. > > Reviewed-by: Janosch Frank <frankja@xxxxxxxxxxxxxxxxxx> with one nit below > Thanks! >> @@ -889,7 +879,6 @@ static void gmap_pte_op_end(spinlock_t *ptl) >> * >> * Called with sg->mm->mmap_sem in read. >> * >> - * Note: Can also be called for shadow gmaps. > > How about also getting rid of the line above this one? > Sure, can the person picking this up fix that one up? -- Thanks, David / dhildenb
