swiotlb-xen: ensure to issue well-formed XENMEM_exchange requests

While the hypervisor hasn't been enforcing this, we would still better avoid issuing requests with GFNs not aligned to the requested order. Instead of altering the value also in the call to panic(), drop it there for being static and hence easy to determine without being part of the panic message. Signed-off-by: Jan Beulich <[email protected]> Reviewed-by: Stefano Stabellini <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Juergen Gross <[email protected]>
josf · Sep 20, 2021 · 9074c79 · 9074c79
1 parent f28347c
commit 9074c79
Showing 1 changed file with 4 additions and 3 deletions.
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
@@ -230,10 +230,11 @@ void __init xen_swiotlb_init_early(void)
 	/*
 	 * Get IO TLB memory from any location.
 	 */
-	start = memblock_alloc(PAGE_ALIGN(bytes), PAGE_SIZE);
+	start = memblock_alloc(PAGE_ALIGN(bytes),
+			       IO_TLB_SEGSIZE << IO_TLB_SHIFT);
 	if (!start)
-		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
-		      __func__, PAGE_ALIGN(bytes), PAGE_SIZE);
+		panic("%s: Failed to allocate %lu bytes\n",
+		      __func__, PAGE_ALIGN(bytes));
 
 	/*
 	 * And replace that memory with pages under 4GB.