Re: [PATCH v6 12/14] KVM: selftests: Add dirty ring buffer test

[Peter Xu <peterx@redhat.com>]

On Tue, Mar 10, 2020 at 09:18:47AM +0100, Andrew Jones wrote:
> On Mon, Mar 09, 2020 at 06:25:29PM -0400, Peter Xu wrote:
> > +void *vcpu_map_dirty_ring(struct kvm_vm *vm, uint32_t vcpuid)
> > +{
> > +	struct vcpu *vcpu;
> > +	uint32_t size = vm->dirty_ring_size;
> > +
> > +	TEST_ASSERT(size > 0, "Should enable dirty ring first");
> > +
> > +	vcpu = vcpu_find(vm, vcpuid);
> > +
> > +	TEST_ASSERT(vcpu, "Cannot find vcpu %u", vcpuid);
> > +
> > +	if (!vcpu->dirty_gfns) {
> > +		void *addr;
> > +
> > +		addr = mmap(NULL, size, PROT_READ,
> > +			    MAP_PRIVATE, vcpu->fd,
> > +			    vm->page_size * KVM_DIRTY_LOG_PAGE_OFFSET);
> > +		TEST_ASSERT(addr == MAP_FAILED, "Dirty ring mapped private");
> > +
> > +		addr = mmap(NULL, size, PROT_READ | PROT_EXEC,
> > +			    MAP_PRIVATE, vcpu->fd,
> > +			    vm->page_size * KVM_DIRTY_LOG_PAGE_OFFSET);
> > +		TEST_ASSERT(addr == MAP_FAILED, "Dirty ring mapped exec");
> > +
> > +		addr = mmap(NULL, size, PROT_READ | PROT_WRITE,
> > +			    MAP_SHARED, vcpu->fd,
> > +			    vm->page_size * KVM_DIRTY_LOG_PAGE_OFFSET);
> 
> No TEST_ASSERT for this mmap?

It'll be used (verified) later. :) Though never harm to add one!

Thanks,
> 
> > +
> > +		vcpu->dirty_gfns = addr;
> > +		vcpu->dirty_gfns_count = size / sizeof(struct kvm_dirty_gfn);
> > +	}
> > +
> > +	return vcpu->dirty_gfns;
> > +}
> 

-- 
Peter Xu