rpms/kernel/F-11 ftrace-check-for-failure-for-all-conversions.patch, NONE, 1.1 ftrace-use-module-notifier-for-function-tracer.patch, NONE, 1.1 tracing-correct-module-boundaries-for-ftrace_release.patch, NONE, 1.1 kernel.spec, 1.1759, 1.1760

[Chuck Ebbert]

Author: cebbert

Update of /cvs/pkgs/rpms/kernel/F-11
In directory cvs1.fedora.phx.redhat.com:/tmp/cvs-serv22922

Modified Files:
	kernel.spec 
Added Files:
	ftrace-check-for-failure-for-all-conversions.patch 
	ftrace-use-module-notifier-for-function-tracer.patch 
	tracing-correct-module-boundaries-for-ftrace_release.patch 
Log Message:
Critical ftrace fixes:
  ftrace-use-module-notifier-for-function-tracer.patch
  ftrace-check-for-failure-for-all-conversions.patch
  tracing-correct-module-boundaries-for-ftrace_release.patch

ftrace-check-for-failure-for-all-conversions.patch:
 ftrace.c |   11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

--- NEW FILE ftrace-check-for-failure-for-all-conversions.patch ---
>From 3279ba37db5d65c4ab0dcdee3b211ccb85bb563f Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt at redhat.com>
Date: Wed, 7 Oct 2009 16:57:56 -0400
Subject: ftrace: check for failure for all conversions

From: Steven Rostedt <srostedt at redhat.com>

commit 3279ba37db5d65c4ab0dcdee3b211ccb85bb563f upstream.

Due to legacy code from back when the dynamic tracer used a daemon,
only core kernel code was checking for failures. This is no longer
the case. We must check for failures any time we perform text modifications.

Signed-off-by: Steven Rostedt <rostedt at goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh at suse.de>

---
 kernel/trace/ftrace.c |   11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1110,14 +1110,9 @@ static void ftrace_replace_code(int enab
 		failed = __ftrace_replace_code(rec, enable);
 		if (failed) {
 			rec->flags |= FTRACE_FL_FAILED;
-			if ((system_state == SYSTEM_BOOTING) ||
-			    !core_kernel_text(rec->ip)) {
-				ftrace_free_rec(rec);
-				} else {
-				ftrace_bug(failed, rec->ip);
-					/* Stop processing */
-					return;
-				}
+			ftrace_bug(failed, rec->ip);
+			/* Stop processing */
+			return;
 		}
 	} while_for_each_ftrace_rec();
 }

ftrace-use-module-notifier-for-function-tracer.patch:
 include/linux/ftrace.h |    7 ---
 include/linux/module.h |    4 ++
 kernel/module.c        |   19 +++-------
 kernel/trace/ftrace.c  |   90 ++++++++++++++++++++++++++++++++++---------------
 4 files changed, 75 insertions(+), 45 deletions(-)

--- NEW FILE ftrace-use-module-notifier-for-function-tracer.patch ---
From: Steven Rostedt <srostedt at redhat.com>
Date: Wed, 15 Apr 2009 17:24:06 +0000 (-0400)
Subject: ftrace: use module notifier for function tracer
X-Git-Tag: v2.6.31-rc1~401^2~151
X-Git-Url: http://git.kernel.org/?p=linux%2Fkernel%2Fgit%2Ftorvalds%2Flinux-2.6.git;a=commitdiff_plain;h=93eb677d74a4f7d3edfb678c94f6c0544d9fbad2

ftrace: use module notifier for function tracer

[ backported to 2.6.30 ]

The hooks in the module code for the function tracer must be called
before any of that module code runs. The function tracer hooks
modify the module (replacing calls to mcount to nops). If the code
is executed while the change occurs, then the CPU can take a GPF.

To handle the above with a bit of paranoia, I originally implemented
the hooks as calls directly from the module code.

After examining the notifier calls, it looks as though the start up
notify is called before any of the module's code is executed. This makes
the use of the notify safe with ftrace.

Only the startup notify is required to be "safe". The shutdown simply
removes the entries from the ftrace function list, and does not modify
any code.

This change has another benefit. It removes a issue with a reverse dependency
in the mutexes of ftrace_lock and module_mutex.

[ Impact: fix lock dependency bug, cleanup ]

Cc: Rusty Russell <rusty at rustcorp.com.au>
Signed-off-by: Steven Rostedt <rostedt at goodmis.org>
---

diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 53869be..97c83e1 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -233,8 +233,6 @@ extern int ftrace_arch_read_dyn_info(char *buf, int size);
 
 extern int skip_trace(unsigned long ip);
 
-extern void ftrace_release(void *start, unsigned long size);
-
 extern void ftrace_disable_daemon(void);
 extern void ftrace_enable_daemon(void);
 #else
@@ -325,13 +323,8 @@ static inline void __ftrace_enabled_restore(int enabled)
 
 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
 extern void ftrace_init(void);
-extern void ftrace_init_module(struct module *mod,
-			       unsigned long *start, unsigned long *end);
 #else
 static inline void ftrace_init(void) { }
-static inline void
-ftrace_init_module(struct module *mod,
-		   unsigned long *start, unsigned long *end) { }
 #endif
 
 /*
diff --git a/include/linux/module.h b/include/linux/module.h
index 6155fa4..a8f2c0a 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -341,6 +341,10 @@ struct module
 	const char **trace_bprintk_fmt_start;
 	unsigned int num_trace_bprintk_fmt;
 #endif
+#ifdef CONFIG_FTRACE_MCOUNT_RECORD
+	unsigned long *ftrace_callsites;
+	unsigned int num_ftrace_callsites;
+#endif

 #ifdef CONFIG_MODULE_UNLOAD
 	/* What modules depend on me? */
diff --git a/kernel/module.c b/kernel/module.c
index a039470..2383e60 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -1490,9 +1490,6 @@ static void free_module(struct module *mod)
 	/* Free any allocated parameters. */
 	destroy_params(mod->kp, mod->num_kp);
 
-	/* release any pointers to mcount in this module */
-	ftrace_release(mod->module_core, mod->core_size);
-
 	/* This may be NULL, but that's OK */
 	module_free(mod, mod->module_init);
 	kfree(mod->args);
@@ -1893,11 +1890,9 @@ static noinline struct module *load_module(void __user *umod,
 	unsigned int symindex = 0;
 	unsigned int strindex = 0;
 	unsigned int modindex, versindex, infoindex, pcpuindex;
-	unsigned int num_mcount;
 	struct module *mod;
 	long err = 0;
 	void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
-	unsigned long *mseg;
 	mm_segment_t old_fs;
 
 	DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
@@ -2179,7 +2174,13 @@ static noinline struct module *load_module(void __user *umod,
 					sizeof(*mod->tracepoints),
 					&mod->num_tracepoints);
 #endif
-
+#ifdef CONFIG_FTRACE_MCOUNT_RECORD
+	/* sechdrs[0].sh_size is always zero */
+	mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
+					     "__mcount_loc",
+					     sizeof(*mod->ftrace_callsites),
+					     &mod->num_ftrace_callsites);
+#endif
 #ifdef CONFIG_MODVERSIONS
 	if ((mod->num_syms && !mod->crcs)
 	    || (mod->num_gpl_syms && !mod->gpl_crcs)
@@ -2244,11 +2245,6 @@ static noinline struct module *load_module(void __user *umod,
 			dynamic_debug_setup(debug, num_debug);
 	}
 
-	/* sechdrs[0].sh_size is always zero */
-	mseg = section_objs(hdr, sechdrs, secstrings, "__mcount_loc",
-			    sizeof(*mseg), &num_mcount);
-	ftrace_init_module(mod, mseg, mseg + num_mcount);
-
 	err = module_finalize(hdr, sechdrs, mod);
 	if (err < 0)
 		goto cleanup;
@@ -2309,7 +2305,6 @@ static noinline struct module *load_module(void __user *umod,
  cleanup:
 	kobject_del(&mod->mkobj.kobj);
 	kobject_put(&mod->mkobj.kobj);
-	ftrace_release(mod->module_core, mod->core_size);
  free_unload:
 	module_unload_free(mod);
 #if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index a234889..5b606f4 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -916,30 +916,6 @@ static void ftrace_free_rec(struct dyn_ftrace *rec)
 	rec->flags |= FTRACE_FL_FREE;
 }
 
-void ftrace_release(void *start, unsigned long size)
-{
-	struct dyn_ftrace *rec;
-	struct ftrace_page *pg;
-	unsigned long s = (unsigned long)start;
-	unsigned long e = s + size;
-
-	if (ftrace_disabled || !start)
-		return;
-
-	mutex_lock(&ftrace_lock);
-	do_for_each_ftrace_rec(pg, rec) {
-		if ((rec->ip >= s) && (rec->ip < e)) {
-			/*
-			 * rec->ip is changed in ftrace_free_rec()
-			 * It should not between s and e if record was freed.
-			 */
-			FTRACE_WARN_ON(rec->flags & FTRACE_FL_FREE);
-			ftrace_free_rec(rec);
-		}
-	} while_for_each_ftrace_rec();
-	mutex_unlock(&ftrace_lock);
-}
-
 static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip)
 {
 	struct dyn_ftrace *rec;
@@ -2752,14 +2728,72 @@ static int ftrace_convert_nops(struct module *mod,
 	return 0;
 }
 
-void ftrace_init_module(struct module *mod,
-			unsigned long *start, unsigned long *end)
+#ifdef CONFIG_MODULES
+void ftrace_release(void *start, void *end)
+{
+	struct dyn_ftrace *rec;
+	struct ftrace_page *pg;
+	unsigned long s = (unsigned long)start;
+	unsigned long e = (unsigned long)end;
+
+	if (ftrace_disabled || !start || start == end)
+		return;
+
+	mutex_lock(&ftrace_lock);
+	do_for_each_ftrace_rec(pg, rec) {
+		if ((rec->ip >= s) && (rec->ip < e)) {
+			/*
+			 * rec->ip is changed in ftrace_free_rec()
+			 * It should not between s and e if record was freed.
+			 */
+			FTRACE_WARN_ON(rec->flags & FTRACE_FL_FREE);
+			ftrace_free_rec(rec);
+		}
+	} while_for_each_ftrace_rec();
+	mutex_unlock(&ftrace_lock);
+}
+
+static void ftrace_init_module(struct module *mod,
+			       unsigned long *start, unsigned long *end)
 {
 	if (ftrace_disabled || start == end)
 		return;
 	ftrace_convert_nops(mod, start, end);
 }
 
+static int ftrace_module_notify(struct notifier_block *self,
+				unsigned long val, void *data)
+{
+	struct module *mod = data;
+
+	switch (val) {
+	case MODULE_STATE_COMING:
+		ftrace_init_module(mod, mod->ftrace_callsites,
+				   mod->ftrace_callsites +
+				   mod->num_ftrace_callsites);
+		break;
+	case MODULE_STATE_GOING:
+		ftrace_release(mod->ftrace_callsites,
+			       mod->ftrace_callsites +
+			       mod->num_ftrace_callsites);
+		break;
+	}
+
+	return 0;
+}
+#else
+static int ftrace_module_notify(struct notifier_block *self,
+				unsigned long val, void *data)
+{
+	return 0;
+}
+#endif /* CONFIG_MODULES */
+
+struct notifier_block ftrace_module_nb = {
+	.notifier_call = ftrace_module_notify,
+	.priority = 0,
+};
+
 extern unsigned long __start_mcount_loc[];
 extern unsigned long __stop_mcount_loc[];
 
@@ -2791,6 +2825,10 @@ void __init ftrace_init(void)
 				  __start_mcount_loc,
 				  __stop_mcount_loc);
 
+	ret = register_module_notifier(&ftrace_module_nb);
+	if (!ret)
+		pr_warning("Failed to register trace ftrace module notifier\n");
+
 	return;
  failed:
 	ftrace_disabled = 1;

tracing-correct-module-boundaries-for-ftrace_release.patch:
 include/linux/ftrace.h |    2 +-
 kernel/trace/ftrace.c  |   12 ++++--------
 2 files changed, 5 insertions(+), 9 deletions(-)

--- NEW FILE tracing-correct-module-boundaries-for-ftrace_release.patch ---
>From e7247a15ff3bbdab0a8b402dffa1171e5c05a8e0 Mon Sep 17 00:00:00 2001
From: jolsa at redhat.com <jolsa at redhat.com>
Date: Wed, 7 Oct 2009 19:00:35 +0200
Subject: tracing: correct module boundaries for ftrace_release

From: jolsa at redhat.com <jolsa at redhat.com>

commit e7247a15ff3bbdab0a8b402dffa1171e5c05a8e0 upstream.

When the module is about the unload we release its call records.
The ftrace_release function was given wrong values representing
the module core boundaries, thus not releasing its call records.

Plus making ftrace_release function module specific.

Signed-off-by: Jiri Olsa <jolsa at redhat.com>
LKML-Reference: <1254934835-363-3-git-send-email-jolsa at redhat.com>
Signed-off-by: Steven Rostedt <rostedt at goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh at suse.de>

---
 include/linux/ftrace.h |    2 +-
 kernel/trace/ftrace.c  |   12 ++++--------
 2 files changed, 5 insertions(+), 9 deletions(-)

--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -241,7 +241,7 @@ extern void ftrace_enable_daemon(void);
 # define ftrace_set_filter(buf, len, reset)	do { } while (0)
 # define ftrace_disable_daemon()		do { } while (0)
 # define ftrace_enable_daemon()			do { } while (0)
-static inline void ftrace_release(void *start, unsigned long size) { }
+static inline void ftrace_release_mod(struct module *mod) {}
 static inline int register_ftrace_command(struct ftrace_func_command *cmd)
 {
 	return -EINVAL;
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2801,19 +2801,17 @@ static int ftrace_convert_nops(struct mo
 }
 
 #ifdef CONFIG_MODULES
-void ftrace_release(void *start, void *end)
+void ftrace_release_mod(struct module *mod)
 {
 	struct dyn_ftrace *rec;
 	struct ftrace_page *pg;
-	unsigned long s = (unsigned long)start;
-	unsigned long e = (unsigned long)end;
 
-	if (ftrace_disabled || !start || start == end)
+	if (ftrace_disabled)
 		return;
 
 	mutex_lock(&ftrace_lock);
 	do_for_each_ftrace_rec(pg, rec) {
-		if ((rec->ip >= s) && (rec->ip < e)) {
+		if (within_module_core(rec->ip, mod)) {
 			/*
 			 * rec->ip is changed in ftrace_free_rec()
 			 * It should not between s and e if record was freed.
@@ -2845,9 +2843,7 @@ static int ftrace_module_notify(struct n
 				   mod->num_ftrace_callsites);
 		break;
 	case MODULE_STATE_GOING:
-		ftrace_release(mod->ftrace_callsites,
-			       mod->ftrace_callsites +
-			       mod->num_ftrace_callsites);
+		ftrace_release_mod(mod);
 		break;
 	}
 


Index: kernel.spec
===================================================================
RCS file: /cvs/pkgs/rpms/kernel/F-11/kernel.spec,v
retrieving revision 1.1759
retrieving revision 1.1760
diff -u -p -r1.1759 -r1.1760
--- kernel.spec	8 Oct 2009 06:01:21 -0000	1.1759
+++ kernel.spec	12 Oct 2009 14:07:05 -0000	1.1760
@@ -780,6 +780,10 @@ Patch15300: x86-increase-min_gap-to-incl
 # x86: Don't leak 64-bit reg contents to 32-bit tasks.
 Patch15400: x86-dont-leak-64-bit-kernel-register-values.patch
 
+# critical ftrace fixes
+Patch15500: ftrace-use-module-notifier-for-function-tracer.patch
+Patch15510: ftrace-check-for-failure-for-all-conversions.patch
+Patch15520: tracing-correct-module-boundaries-for-ftrace_release.patch
 
 %endif
 
@@ -1458,6 +1462,11 @@ ApplyPatch x86-increase-min_gap-to-inclu
 
 ApplyPatch x86-dont-leak-64-bit-kernel-register-values.patch
 
+# critical ftrace fixes
+ApplyPatch ftrace-use-module-notifier-for-function-tracer.patch
+ApplyPatch ftrace-check-for-failure-for-all-conversions.patch
+ApplyPatch tracing-correct-module-boundaries-for-ftrace_release.patch
+
 # END OF PATCH APPLICATIONS
 
 %endif
@@ -2046,7 +2055,13 @@ fi
 # and build.
 
 %changelog
-* Thu Oct 08 2009 Ben Skeggs <bskeggs at redhat.com>     2.6.30.9-79
+* Mon Oct 12 2009  Chuck Ebbert <cebbert at redhat.com>  2.6.30.9-81
+- Critical ftrace fixes:
+  ftrace-use-module-notifier-for-function-tracer.patch
+  ftrace-check-for-failure-for-all-conversions.patch
+  tracing-correct-module-boundaries-for-ftrace_release.patch
+
+* Thu Oct 08 2009 Ben Skeggs <bskeggs at redhat.com>     2.6.30.9-80
 - ppc: compile nvidiafb as a module only, nvidiafb+nouveau = bang! (rh#491308)
 
 * Wed Oct 07 2009 Dave Jones <davej at redhat.com>       2.6.30.9-78