On Wed, 2 May 2018 09:16:50 +0200 Christian Borntraeger <borntraeger@xxxxxxxxxx> wrote: > On 05/01/2018 12:01 AM, Marc Orr wrote: > > Actually, I don't follow. Radim said: > > "I'd prefer to have one patch that switches all architectures to vzalloc > > (this patch + hunk for x86)..." > > > > But Christian said vzalloc doesn't work for s390. > > I said > --- > I dont think this is necessarily safe. This contains kvm_arch and you > would need to verify that no architecture has data in struct kvm_arch > that must be allocated with kmalloc. Fo example on s390 kernel virtual > == kernel real for kmalloc so some driver might rely on that. > FWIW, it looks like the s390 struct kvm_arch is fine, but this requires > more review I guess. > --- > > so my statement was more on the "it could break" side. > Right now it looks like that most critical data structure (crypto control > block, stfle and others) are already pointers and being allocated > separately but this needs some review. > > David, Conny, Janosch, can you please also check struct kvm_arch on z for > data structures that are passed directly to the hardware? Those will break > if we switch to vzalloc. >From what I can see, the structures sensitive to kzalloc vs. vzalloc are all in separately allocated blocks.
