xen/setup: Don't relocate p2m over existing one

When relocating the p2m, take special care not to relocate it so that is overlaps with the current location of the p2m/initrd. This is needed since the full extent of the current location is not marked as a reserved region in the e820. This was seen to happen to a dom0 with a large initial p2m and a small reserved region in the middle of the initial p2m. Signed-off-by: Ross Lagerwall <[email protected]> Reviewed-by: Juergen Gross <[email protected]> Signed-off-by: Juergen Gross <[email protected]>
boxfire · Dec 22, 2016 · 7ecec85 · 7ecec85
1 parent 709613a
commit 7ecec85
Showing 1 changed file with 3 additions and 3 deletions.
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
@@ -713,10 +713,9 @@ static void __init xen_reserve_xen_mfnlist(void)
 		size = PFN_PHYS(xen_start_info->nr_p2m_frames);
 	}
 
-	if (!xen_is_e820_reserved(start, size)) {
-		memblock_reserve(start, size);
+	memblock_reserve(start, size);
+	if (!xen_is_e820_reserved(start, size))
 		return;
-	}
 
 #ifdef CONFIG_X86_32
 	/*
@@ -727,6 +726,7 @@ static void __init xen_reserve_xen_mfnlist(void)
 	BUG();
 #else
 	xen_relocate_p2m();
+	memblock_free(start, size);
 #endif
 }