From: Peter Martuccelli <peterm@redhat.com>
Date: Mon, 10 Dec 2007 16:48:21 -0500
Subject: [ipmi] legacy ioport setup changes
Message-id: 200712102148.lBALmLe6021301@redrum.boston.redhat.com
O-Subject: [RHEL 5.2][Patch 5/7] IPMI: Legacy ioport setup changes
Bugzilla: 279191

The setup code on pseries systems needs to prevent non-whitelist entries from
probing the default IPMI ports.  Upstream has already combined the platform
specific setup code functions into a common setup routine.  While this approach
resolved the problem, it broke kABI.  The following patch is a backport of the
common upstream setup code, (arch/powerpc/kernel/setup-common.c).  This
allows pseries systems without any underlying IPMI hardware support to fail
the loading of the ipmi_si driver in a graceful manner.  Without this patch
pseries systems will panic on the port_inb() call while probing the default
IPMI port addresses.  The remaining PPC platform specific check_legacy_ioport()
functions already return -ENODEV by default, so no additional setup routines
need to be changed.

IBM has verified the fix, (thanks to Scott for testing).

Please review and ACK.

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 9e3f580..0ff332c 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -390,27 +390,27 @@ static void __init pSeries_init_early(void)
 
 static int pSeries_check_legacy_ioport(unsigned int baseport)
 {
-	struct device_node *np;
+	struct device_node *np = NULL;
+	int ret = -ENODEV;
 
 #define I8042_DATA_REG	0x60
 #define FDC_BASE	0x3f0
 
-
 	switch(baseport) {
 	case I8042_DATA_REG:
 		np = of_find_node_by_type(NULL, "8042");
-		if (np == NULL)
-			return -ENODEV;
-		of_node_put(np);
 		break;
 	case FDC_BASE:
 		np = of_find_node_by_type(NULL, "fdc");
-		if (np == NULL)
-			return -ENODEV;
-		of_node_put(np);
+		break;
+	default:
+		/* ipmi is supposed to fail here */
 		break;
 	}
-	return 0;
+	if (!np)
+		return ret;
+	of_node_put(np);
+	return ret;
 }
 
 /*