From c43e0ae1db16a6d9878dd6e9007129f517191fa7 Mon Sep 17 00:00:00 2001
From: Andrew Morton <akpm@osdl.org>
Date: Wed, 30 Jan 2008 13:30:47 +0100
Subject: [PATCH] --- yaml --- r: 79863 b: refs/heads/master c:
 022eb43419f896a3647f769cdc3b5e13a8fb8ee7 h: refs/heads/master i:   79861:
 4e0c7a253c7ffd4be171a14d40b9aa4279054a65   79859:
 2e4ca2745aa57bb8a2dfc40603c63bd2548898a1   79855:
 87320faa56d82cac731e3f9c1e850f5a05c01a42 v: v3

---
 [refs]                         |  2 +-
 trunk/arch/x86/mm/highmem_32.c | 47 +++++++++++++++++++++++++++++++++-
 2 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index 27b8ad307ef2..d18e97a2f0cf 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 2c0b8a7578f7653e1e5312a5232e8ead563cf477
+refs/heads/master: 022eb43419f896a3647f769cdc3b5e13a8fb8ee7
diff --git a/trunk/arch/x86/mm/highmem_32.c b/trunk/arch/x86/mm/highmem_32.c
index 1c3bf95f7356..3d936f232704 100644
--- a/trunk/arch/x86/mm/highmem_32.c
+++ b/trunk/arch/x86/mm/highmem_32.c
@@ -18,6 +18,49 @@ void kunmap(struct page *page)
 	kunmap_high(page);
 }
 
+static void debug_kmap_atomic_prot(enum km_type type)
+{
+#ifdef CONFIG_DEBUG_HIGHMEM
+	static unsigned warn_count = 10;
+
+	if (unlikely(warn_count == 0))
+		return;
+
+	if (unlikely(in_interrupt())) {
+		if (in_irq()) {
+			if (type != KM_IRQ0 && type != KM_IRQ1 &&
+			    type != KM_BIO_SRC_IRQ && type != KM_BIO_DST_IRQ &&
+			    type != KM_BOUNCE_READ) {
+				WARN_ON(1);
+				warn_count--;
+			}
+		} else if (!irqs_disabled()) {	/* softirq */
+			if (type != KM_IRQ0 && type != KM_IRQ1 &&
+			    type != KM_SOFTIRQ0 && type != KM_SOFTIRQ1 &&
+			    type != KM_SKB_SUNRPC_DATA &&
+			    type != KM_SKB_DATA_SOFTIRQ &&
+			    type != KM_BOUNCE_READ) {
+				WARN_ON(1);
+				warn_count--;
+			}
+		}
+	}
+
+	if (type == KM_IRQ0 || type == KM_IRQ1 || type == KM_BOUNCE_READ ||
+			type == KM_BIO_SRC_IRQ || type == KM_BIO_DST_IRQ) {
+		if (!irqs_disabled()) {
+			WARN_ON(1);
+			warn_count--;
+		}
+	} else if (type == KM_SOFTIRQ0 || type == KM_SOFTIRQ1) {
+		if (irq_count() == 0 && !irqs_disabled()) {
+			WARN_ON(1);
+			warn_count--;
+		}
+	}
+#endif
+}
+
 /*
  * kmap_atomic/kunmap_atomic is significantly faster than kmap/kunmap because
  * no global lock is needed and because the kmap code must perform a global TLB
@@ -30,8 +73,10 @@ void *kmap_atomic_prot(struct page *page, enum km_type type, pgprot_t prot)
 {
 	enum fixed_addresses idx;
 	unsigned long vaddr;
-
 	/* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
+
+	debug_kmap_atomic_prot(type);
+
 	pagefault_disable();
 
 	if (!PageHighMem(page))