Hello, Anvin
You are right. Thanks!
Hello, All
Please review it again. Thanks!
From bf7506ac7e9ce0df0b915164dbb7a6d858ef2e40 Mon Sep 17 00:00:00 2001
From: jzha144 <jun.zhang@xxxxxxxxx>
Date: Wed, 31 Oct 2012 08:51:18 +0800
Subject: [PATCH] When we are doing a crash dump, we still need non-E820_RAM
memory type address information in order to do I/O. so only
remove all RAM ranges which need to be dumped.
Signed-off-by: jzha144 <jun.zhang@xxxxxxxxx>
---
arch/x86/kernel/e820.c | 9 +++++++++
1 files changed, 9 insertions(+), 0 deletions(-)
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index df06ade..77be839 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -851,6 +851,15 @@ static int __init parse_memmap_opt(char *p)
* reset.
*/
saved_max_pfn = e820_end_of_ram_pfn();
+
+ /*
+ * We are doing a crash dump, so remove all RAM ranges
+ * as they are the ones that need to be dumped.
+ * We still need all non-RAM information in order to do I/O.
+ */
+ e820_remove_range(0, ULLONG_MAX, E820_RAM, 1);
+ userdef = 1;
+ return 0;
#endif
e820.nr_map = 0;
userdef = 1;