From: Jan Beulich <jbeulich@novell.com>
Date: Wed, 6 May 2009 12:02:19 +0000 (+0100)
Subject: x86: fix boot hang in early_reserve_e820()
X-Git-Tag: firefly_0821_release~14210^2~4
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=61438766514a2d7f191ce1b3cf6812eabbef4ef7;p=firefly-linux-kernel-4.4.55.git

x86: fix boot hang in early_reserve_e820()

If the first non-reserved (sub-)range doesn't fit the size requested,
an endless loop will be entered. If a range returned from
find_e820_area_size() turns out insufficient in size, the range must
be skipped before calling the function again.

[ Impact: fixes boot hang on some platforms ]

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
---

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index ef2c3563357d..006281302925 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -1074,12 +1074,13 @@ u64 __init early_reserve_e820(u64 startt, u64 sizet, u64 align)
 	u64 addr;
 	u64 start;
 
-	start = startt;
-	while (size < sizet && (start + 1))
+	for (start = startt; ; start += size) {
 		start = find_e820_area_size(start, &size, align);
-
-	if (size < sizet)
-		return 0;
+		if (!(start + 1))
+			return 0;
+		if (size >= sizet)
+			break;
+	}
 
 #ifdef CONFIG_X86_32
 	if (start >= MAXMEM)