[PATCH] x86/setup: correct off-by-1 in module mapping

[Jan Beulich]

If a module's length is an exact multiple of PAGE_SIZE, the 2nd argument
passed to set_pdx_range() would be one larger than intended. Use
PFN_{UP,DOWN}() there instead.

Fixes: cd7cc5320bb2 ("x86/boot: add start and size fields to struct 
boot_module")
Signed-off-by: Jan Beulich <jbeul...@suse.com>

--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -1730,7 +1730,7 @@ void asmlinkage __init noreturn __start_
     {
         unsigned long s = bi->mods[i].start, l = bi->mods[i].size;
 
-        set_pdx_range(paddr_to_pfn(s), paddr_to_pfn(s + l) + 1);
+        set_pdx_range(PFN_DOWN(s), PFN_UP(s + l));
         map_pages_to_xen((unsigned long)maddr_to_virt(s), maddr_to_mfn(s),
                          PFN_UP(l), PAGE_HYPERVISOR);
     }