Commit ce6b8ccd authored by Juergen Gross's avatar Juergen Gross
Browse files

xen/xenbus: fix xenbus_setup_ring() 



Commit 4573240f ("xen/xenbus: eliminate xenbus_grant_ring()")
introduced an error for initialization of multi-page rings.

Cc: stable@vger.kernel.org
Fixes: 4573240f ("xen/xenbus: eliminate xenbus_grant_ring()")
Reported-by: default avatarSander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
Reviewed-by: default avatarJan Beulich <jbeulich@suse.com>
Reviewed-by: default avatarOleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
parent e9ea0b30

drivers/xen/xenbus/xenbus_client.c

+6 −3
Original line number Diff line number Diff line
@@ -382,9 +382,10 @@ int xenbus_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr, 
	unsigned long ring_size = nr_pages * XEN_PAGE_SIZE;

	grant_ref_t gref_head;

	unsigned int i;

	void *addr;

	int ret;



	*vaddr = alloc_pages_exact(ring_size, gfp | __GFP_ZERO);

	addr = *vaddr = alloc_pages_exact(ring_size, gfp | __GFP_ZERO);

	if (!*vaddr) {

		ret = -ENOMEM;

		goto err;
@@ -401,13 +402,15 @@ int xenbus_setup_ring(struct xenbus_device *dev, gfp_t gfp, void **vaddr, 
		unsigned long gfn;



		if (is_vmalloc_addr(*vaddr))

			gfn = pfn_to_gfn(vmalloc_to_pfn(vaddr[i]));

			gfn = pfn_to_gfn(vmalloc_to_pfn(addr));

		else

			gfn = virt_to_gfn(vaddr[i]);

			gfn = virt_to_gfn(addr);



		grefs[i] = gnttab_claim_grant_reference(&gref_head);

		gnttab_grant_foreign_access_ref(grefs[i], dev->otherend_id,

						gfn, 0);



		addr += XEN_PAGE_SIZE;

	}



	return 0;