From: Ian Campbell <ijc@hellion.org.uk>
Date: Thu, 28 Feb 2008 23:16:49 +0000 (+0000)
Subject: x86/xen: fix DomU boot problem
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=87d034f3139b5f0d93df2ba58f37d6f2c2c7eeb6;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

x86/xen: fix DomU boot problem

Construct Xen guest e820 map with a hole between 640K-1M.

It's pure luck that Xen kernels have gotten away with it in the past.

The patch below seems like the right thing to do. It certainly boots in
a domU without the DMI problem (without any of the other related patches
such as Alexander's).

Signed-off-by: Ian Campbell <ijc@hellion.org.uk>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Tested-by: Mark McLoughlin <markmc@redhat.com>
Acked-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
---

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 3bad4773a2f3..2341492bf7a0 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -38,7 +38,8 @@ char * __init xen_memory_setup(void)
 	unsigned long max_pfn = xen_start_info->nr_pages;
 
 	e820.nr_map = 0;
-	add_memory_region(0, PFN_PHYS(max_pfn), E820_RAM);
+	add_memory_region(0, LOWMEMSIZE(), E820_RAM);
+	add_memory_region(HIGH_MEMORY, PFN_PHYS(max_pfn)-HIGH_MEMORY, E820_RAM);
 
 	return "Xen";
 }