rpms/kernel/devel linux-2.6-x86-setup-handle-improperly-terminated-E820.patch, NONE, 1.1 kernel.spec, 1.190, 1.191

[Chuck Ebbert (cebbert)]

Author: cebbert

Update of /cvs/pkgs/rpms/kernel/devel
In directory cvs-int.fedora.redhat.com:/tmp/cvs-serv24168

Modified Files:
	kernel.spec 
Added Files:
	linux-2.6-x86-setup-handle-improperly-terminated-E820.patch 
Log Message:
* Wed Sep 26 2007 Chuck Ebbert <cebbert at redhat.com>
- x86 e820 bugfix


linux-2.6-x86-setup-handle-improperly-terminated-E820.patch:

--- NEW FILE linux-2.6-x86-setup-handle-improperly-terminated-E820.patch ---
commit 2efa33f81ef56e7700c09a3d8a881c96692149e5
Author: H. Peter Anvin <hpa at zytor.com>
Date:   Wed Sep 26 14:11:43 2007 -0700

    [x86 setup] Handle case of improperly terminated E820 chain
    
    At least one system (a Geode system with a Digital Logic BIOS) has
    been found which suddenly stops reporting the SMAP signature when
    reading the E820 memory chain.  We can't know what, exactly, broke in
    the BIOS, so if we detect this situation, declare the E820 data
    unusable and fall back to E801.
    
    Also, revert to original behavior of always probing all memory
    methods; that way all the memory information is available to the
    kernel.
    
    Signed-off-by: H. Peter Anvin <hpa at zytor.com>
    Cc: Jordan Crouse <jordan.crouse at amd.com>
    Cc: Joerg Pommnitz <pommnitz at yahoo.com>

diff --git a/arch/i386/boot/memory.c b/arch/i386/boot/memory.c
index 1a2e62d..bccaa1c 100644
--- a/arch/i386/boot/memory.c
+++ b/arch/i386/boot/memory.c
@@ -20,6 +20,7 @@
 
 static int detect_memory_e820(void)
 {
+	int count = 0;
 	u32 next = 0;
 	u32 size, id;
 	u8 err;
@@ -33,14 +34,24 @@ static int detect_memory_e820(void)
 		      "=m" (*desc)
 		    : "D" (desc), "a" (0xe820));
 
-		if (err || id != SMAP)
+		/* Some BIOSes stop returning SMAP in the middle of
+		   the search loop.  We don't know exactly how the BIOS
+		   screwed up the map at that point, we might have a
+		   partial map, the full map, or complete garbage, so
+		   just return failure. */
+		if (id != SMAP) {
+			count = 0;
 			break;
+		}
 
-		boot_params.e820_entries++;
+		if (err)
+			break;
+
+		count++;
 		desc++;
-	} while (next && boot_params.e820_entries < E820MAX);
+	} while (next && count < E820MAX);
 
-	return boot_params.e820_entries;
+	return boot_params.e820_entries = count;
 }
 
 static int detect_memory_e801(void)
@@ -89,11 +100,16 @@ static int detect_memory_88(void)
 
 int detect_memory(void)
 {
+	int err = -1;
+
 	if (detect_memory_e820() > 0)
-		return 0;
+		err = 0;
 
 	if (!detect_memory_e801())
-		return 0;
+		err = 0;
+
+	if (!detect_memory_88())
+		err = 0;
 
-	return detect_memory_88();
+	return err;
 }


Index: kernel.spec
===================================================================
RCS file: /cvs/pkgs/rpms/kernel/devel/kernel.spec,v
retrieving revision 1.190
retrieving revision 1.191
diff -u -r1.190 -r1.191
--- kernel.spec	26 Sep 2007 21:03:40 -0000	1.190
+++ kernel.spec	26 Sep 2007 22:38:30 -0000	1.191
@@ -672,6 +672,7 @@
 Patch1515: linux-2.6-lirc.patch
 
 Patch1600: linux-2.6-x86-edd-maxdrive.patch
+Patch1610: linux-2.6-x86-setup-handle-improperly-terminated-E820.patch
 
 #nouveau
 Patch1800: drm-mm-git.patch
@@ -1214,6 +1215,9 @@
 # EDD fix
 ApplyPatch linux-2.6-x86-edd-maxdrive.patch
 
+# e820 bugfix
+ApplyPatch linux-2.6-x86-setup-handle-improperly-terminated-E820.patch
+
 # END OF PATCH APPLICATIONS
 
 %endif
@@ -1806,6 +1810,9 @@
 
 %changelog
 * Wed Sep 26 2007 Chuck Ebbert <cebbert at redhat.com>
+- x86 e820 bugfix
+
+* Wed Sep 26 2007 Chuck Ebbert <cebbert at redhat.com>
 - Linux 2.6.23-rc8-git1
 
 * Wed Sep 26 2007 Dave Jones <davej at redhat.com>