Re: __iounmap: bad address c00f0000 (Re: 2.6.10-bk5)

[Al Viro <viro@parcelfarce.linux.theplanet.co.uk>]

On Mon, Jan 03, 2005 at 12:24:36PM -0500, Len Brown wrote:
> On Sun, 2005-01-02 at 19:14, Michael Geithe wrote:
> 
> > DMI 2.3 present.
> > __iounmap: bad address c00f0000
> > ACPI: RSDP (v000 AMI                                   ) @ 0x000fa380
> 
> Not and ACPI issue:-)
> 
> Looks like the warning is provoked by Al Viro's update to dmi_iterate().
> Perhaps there is a conflict between dmi_table()'s bt_iounmap(),
> and dmi_iterate()'s new iounmap() on the same address?

No.

diff -urN RC10-base/arch/i386/kernel/dmi_scan.c RC10-current/arch/i386/kernel/dmi_scan.c
--- RC10-base/arch/i386/kernel/dmi_scan.c	2004-12-27 06:06:58.000000000 -0500
+++ RC10-current/arch/i386/kernel/dmi_scan.c	2005-01-03 12:46:48.211661680 -0500
@@ -104,6 +104,11 @@
 	u8 buf[15];
 	char __iomem *p, *q;
 
+	/*
+	 * no iounmap() for that ioremap(); it would be a no-op, but it's
+	 * so early in setup that sucker gets confused into doing what
+	 * it shouldn't if we actually call it.
+	 */
 	for (p = q = ioremap(0xF0000, 0x10000); q < p + 0x10000; q += 16) {
 		memcpy_fromio(buf, q, 15);
 		if(memcmp(buf, "_DMI_", 5)==0 && dmi_checksum(buf))
@@ -125,13 +130,10 @@
 				num, len));
 			dmi_printk((KERN_INFO "DMI table at 0x%08X.\n",
 				base));
-			if(dmi_table(base,len, num, decode)==0) {
-				iounmap(p);
+			if(dmi_table(base,len, num, decode)==0)
 				return 0;
-			}
 		}
 	}
-	iounmap(p);
 	return -1;
 }