move kobject warn patch to driver dir

1 files changed, 108 insertions, 0 deletions

diff --git a/driver/warn-when-statically-allocated-kobjects-are-used.patch b/driver/warn-when-statically-allocated-kobjects-are-used.patch
new file mode 100644
index 0000000000000..80424ad46b0a7
--- /dev/null
+++ b/driver/warn-when-statically-allocated-kobjects-are-used.patch
@@ -0,0 +1,108 @@
+From haveblue@us.ibm.com Thu Mar 16 17:30:46 2006
+From: Dave Hansen <haveblue@us.ibm.com>
+Subject: warn when statically-allocated kobjects are used
+Cc: gregkh@suse.de, Dave Hansen <haveblue@us.ibm.com>
+Date: Thu, 16 Mar 2006 17:30:16 -0800
+Message-Id: <20060317013016.5C643E69@localhost.localdomain>
+
+
+One of the top ten sysfs problems is that users use statically
+allocated kobjects.  This patch reminds them that this is a
+naughty thing.
+
+One _really_ nice thing this patch does, is us the kallsyms
+mechanism to print out exactly which symbol is being complained
+about:
+
+The kobject at, or inside devices_subsys+0x14/0x60 is not dynamically allocated.
+
+There are not very many architectures that actually place a
+_sdata or _data symbol in their vmlinux.lds.S.  This patch
+causes link errors in all these cases.  Is there an
+alternative symbol that we can use, or can we use weak
+symbols and detect them, so that they are at least skipped?
+
+Does kernel/kallsyms.c:is_kernel() do the trick, so that we
+don't need to use the asm-generic/sections.h variables at all?
+
+
+Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
+
+
+---
+ arch/i386/kernel/vmlinux.lds.S |    2 ++
+ lib/kobject.c                  |   38 ++++++++++++++++++++++++++++++++++++++
+ 2 files changed, 40 insertions(+)
+
+--- gregkh-2.6.orig/arch/i386/kernel/vmlinux.lds.S
++++ gregkh-2.6/arch/i386/kernel/vmlinux.lds.S
+@@ -35,6 +35,8 @@ SECTIONS
+   __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { *(__ex_table) }
+   __stop___ex_table = .;
+ 
++  _sdata = .;			/* End of text section */
++
+   RODATA
+ 
+   /* writeable */
+--- gregkh-2.6.orig/lib/kobject.c
++++ gregkh-2.6/lib/kobject.c
+@@ -15,6 +15,8 @@
+ #include <linux/module.h>
+ #include <linux/stat.h>
+ #include <linux/slab.h>
++#include <linux/kallsyms.h>
++#include <asm-generic/sections.h>
+ 
+ /**
+  *	populate_dir - populate directory with attributes.
+@@ -120,6 +122,41 @@ char *kobject_get_path(struct kobject *k
+ 	return path;
+ }
+ 
++static int ptr_in_range(void *ptr, void *start, void *end)
++{
++	/*
++	 * This should hopefully get rid of causing warnings
++	 * if the architecture did not set one of the section
++	 * variables up.
++	 */
++	if (start >= end)
++		return 0;
++
++	if ((ptr >= start) && (ptr < end))
++		return 1;
++	return 0;
++}
++
++static void verify_dynamic_kobject_allocation(struct kobject *kobj)
++{
++	if (ptr_in_range(kobj, &_sdata[0], &_edata[0]))
++		goto warn;
++	if (ptr_in_range(kobj, &__bss_start[0], &__bss_stop[0]))
++		goto warn;
++	return;
++warn:
++	pr_debug("---- begin silly warning ----\n");
++	pr_debug("This is a janitorial warning, not a kernel bug.\n");
++#ifdef CONFIG_DEBUG_KOBJECT
++	print_symbol("The kobject at, or inside %s is not dynamically allocated.\n",
++			(unsigned long)kobj);
++#endif
++	pr_debug("kobjects must be dynamically allocated, not static\n");
++	/* dump_stack(); */
++	pr_debug("---- end silly warning ----\n");
++}
++
++
+ /**
+  *	kobject_init - initialize object.
+  *	@kobj:	object in question.
+@@ -127,6 +164,7 @@ char *kobject_get_path(struct kobject *k
+ void kobject_init(struct kobject * kobj)
+ {
+ 	WARN_ON(atomic_read(&kobj->kref.refcount));
++	verify_dynamic_kobject_allocation(kobj);
+ 	kref_init(&kobj->kref);
+ 	INIT_LIST_HEAD(&kobj->entry);
+ 	init_waitqueue_head(&kobj->poll);