# --- T2-COPYRIGHT-BEGIN ---
# t2/package/*/grub2/hotfix-badram-infloop.patch
# Copyright (C) 2024 - 2026 The T2 SDE Project
# SPDX-License-Identifier: GPL-2.0 or patched project license
# --- T2-COPYRIGHT-END ---

Fix badram masks with all bits set as generated by memtest86+:

badram 0x2dbf7f590,0xffffffffffffff80

inf. looping in low / high fill_mask iteration.

--- grub-2.12/grub-core/mmap/mmap.c.vanilla	2024-03-05 22:25:47.314964030 +0100
+++ grub-2.12/grub-core/mmap/mmap.c	2024-03-06 00:42:04.675176109 +0100
@@ -452,6 +462,10 @@
 	  return GRUB_ERR_NONE;
 	}
 
+      /* There are currently few arch with full physical 64-bit address space.
+	 Clear top bit as out mask loops will infinite loop with all bits set. */
+      entry.mask &= (~(0ULL)) >> 1;
+
       /* When part of a page is tainted, we discard the whole of it.  There's
 	 no point in providing sub-page chunks.  */
       entry.mask &= ~(CHUNK_SIZE - 1);