Index: linux-2.4.21-rhel/kernel/sysctl.c
===================================================================
--- linux-2.4.21-rhel.orig/kernel/sysctl.c	2005-01-20 18:52:39.000000000 -0700
+++ linux-2.4.21-rhel/kernel/sysctl.c	2005-05-31 18:47:22.000000000 -0600
@@ -355,6 +355,8 @@
 extern int skip_mapped_pages;
 
 static ctl_table vm_table[] = {
+	{VM_GFP_DEBUG, "vm_gfp_debug",
+	 &vm_gfp_debug, sizeof(int), 0644, NULL, &proc_dointvec},
 	{VM_BDFLUSH, "bdflush", &bdf_prm, 9*sizeof(int), 0644, NULL,
 	 &proc_dointvec_minmax, &sysctl_intvec, NULL,
 	 &bdflush_min, &bdflush_max},
Index: linux-2.4.21-rhel/mm/page_alloc.c
===================================================================
--- linux-2.4.21-rhel.orig/mm/page_alloc.c	2005-05-31 18:29:37.000000000 -0600
+++ linux-2.4.21-rhel/mm/page_alloc.c	2005-05-31 18:49:27.000000000 -0600
@@ -58,6 +58,8 @@
 static int zone_extrafree_max[MAX_NR_ZONES] __initdata = { 1024 , 1024, 0, };
 #endif
 
+int vm_gfp_debug = 0;
+
 /*
  * Temporary debugging check.
  */
@@ -773,8 +775,12 @@
 	}
 
 out_failed:
-	/* No luck.. */
-//	printk(KERN_ERR "__alloc_pages: %lu-order allocation failed.\n", order);
+	if (!(gfp_mask & __GFP_NOWARN)) {
+		printk(KERN_ERR "__alloc_pages: %lu-order allocation failed (gfp=%#x/%i).\n",
+		       order, gfp_mask, !!(current->flags & PF_MEMALLOC));
+		if (unlikely(vm_gfp_debug))
+			dump_stack();
+	}
 	return NULL;
 }
 
Index: linux-2.4.21-rhel/include/linux/sysctl.h
===================================================================
--- linux-2.4.21-rhel.orig/include/linux/sysctl.h	2005-03-18 18:25:26.000000000 -0700
+++ linux-2.4.21-rhel/include/linux/sysctl.h	2005-05-31 18:48:17.000000000 -0600
@@ -153,6 +153,7 @@
 	VM_MIN_READAHEAD=12,    /* Min file readahead */
 	VM_MAX_READAHEAD=13,    /* Max file readahead */
 	VM_OVERCOMMIT_RATIO=16,	/* percent of RAM to allow overcommit in */
+	VM_GFP_DEBUG=18,	/* debug GFP failures */
 	VM_PAGEBUF=22,		/* struct: Control pagebuf parameters */
 	VM_HUGETLB_POOL=23,	/* int: size of the hugetlb pool, in MB */
 	VM_DCACHE_PRIORITY=24,	/* int: priority of the dcache pool */
Index: linux-2.4.21-rhel/include/linux/mm.h
===================================================================
--- linux-2.4.21-rhel.orig/include/linux/mm.h	2005-05-31 18:50:32.000000000 -0600
+++ linux-2.4.21-rhel/include/linux/mm.h	2005-05-31 18:50:45.000000000 -0600
@@ -846,6 +846,7 @@
 #define __GFP_HIGHIO	0x80	/* Can start high mem physical IO? */
 #define __GFP_FS	0x100	/* Can call down to low-level FS? */
 #define __GFP_WIRED	0x200   /* Highmem bias and wired */
+#define __GFP_NOWARN	0x400	/* Don't report error on allocation failure */
 
 #define GFP_NOHIGHIO	(__GFP_HIGH | __GFP_WAIT | __GFP_IO)
 #define GFP_NOIO	(__GFP_HIGH | __GFP_WAIT)
Index: linux-2.4.21-rhel/include/linux/swap.h
===================================================================
--- linux-2.4.21-rhel.orig/include/linux/swap.h	2005-03-18 18:25:26.000000000 -0700
+++ linux-2.4.21-rhel/include/linux/swap.h	2005-05-31 18:52:44.000000000 -0600
@@ -178,6 +178,7 @@
 extern int rebalance_inactive(int);
 extern void wakeup_kswapd(unsigned int);
 extern void rss_free_pages(unsigned int);
+extern int vm_gfp_debug;
 
 /*
  * Limits, in percent, on how large the cache can be and how to do