From: Andrew Morton <akpm@osdl.org>
Date: Fri, 8 Jul 2005 00:56:02 +0000 (-0700)
Subject: [PATCH] iounmap debugging
X-Git-Tag: v2.6.13-rc3~308
X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=c23a4e9649f80a9379d7df4a33bc63b365d5e7fc;p=~emulex%2Finfiniband.git

[PATCH] iounmap debugging

We get sporadic reports of `__iounmap: bad address' coming out.  Add a
dump_stack() to find the culprit.

Try to identify which subsystem is having iounmap() problems.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/arch/i386/mm/ioremap.c b/arch/i386/mm/ioremap.c
index 6b25afc933b..f379b8d6755 100644
--- a/arch/i386/mm/ioremap.c
+++ b/arch/i386/mm/ioremap.c
@@ -228,7 +228,8 @@ EXPORT_SYMBOL(ioremap_nocache);
 void iounmap(volatile void __iomem *addr)
 {
 	struct vm_struct *p;
-	if ((void __force *) addr <= high_memory) 
+
+	if ((void __force *)addr <= high_memory)
 		return;
 
 	/*
@@ -241,9 +242,10 @@ void iounmap(volatile void __iomem *addr)
 		return;
 
 	write_lock(&vmlist_lock);
-	p = __remove_vm_area((void *) (PAGE_MASK & (unsigned long __force) addr));
+	p = __remove_vm_area((void *)(PAGE_MASK & (unsigned long __force)addr));
 	if (!p) { 
 		printk(KERN_WARNING "iounmap: bad address %p\n", addr);
+		dump_stack();
 		goto out_unlock;
 	}