[PATCH 0/2] [GIT PULL][v2.6.36] tracing: fixes for tracing virt guests

[PATCH 0/2] [GIT PULL][v2.6.36] tracing: fixes for tracing virt guests

[Steven Rostedt]

Ingo,

I actually did these fixes back in July for RHEL, but forgot about
them for mainline :-(

Jeremy hit the same bug and set me a fix. It was only part of what
I did in July, so I pulled in his fix and added the second part.

Please pull the latest tip/perf/urgent tree, which can be found at:

  git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git
tip/perf/urgent


Jeremy Fitzhardinge (1):
      tracing/x86: Don't use mcount in pvclock.c

Steven Rostedt (1):
      tracing/x86: Don't use mcount in kvmclock.c

----
 arch/x86/kernel/Makefile |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

[PATCH 1/2] tracing/x86: Dont use mcount in pvclock.c

[Steven Rostedt]

[-- Attachment #1: 0001-tracing-x86-Don-t-use-mcount-in-pvclock.c.patch --]
[-- Type: text/plain, Size: 944 bytes --]

From: Jeremy Fitzhardinge <jeremy@goop.org>

When using a paravirt clock, pvclock.c can be used by sched_clock(),
which in turn is used by the tracing mechanism for timestamps,
which leads to infinite recursion.

Disable mcount/tracing for pvclock.o.

Cc: stable@kernel.org
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
LKML-Reference: <4C9A9A3F.4040201@goop.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 arch/x86/kernel/Makefile |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 0925676..882bbff 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -11,6 +11,7 @@ ifdef CONFIG_FUNCTION_TRACER
 CFLAGS_REMOVE_tsc.o = -pg
 CFLAGS_REMOVE_rtc.o = -pg
 CFLAGS_REMOVE_paravirt-spinlocks.o = -pg
+CFLAGS_REMOVE_pvclock.o = -pg
 CFLAGS_REMOVE_ftrace.o = -pg
 CFLAGS_REMOVE_early_printk.o = -pg
 endif
-- 
1.7.1

[PATCH 2/2] tracing/x86: Dont use mcount in kvmclock.c

[Steven Rostedt]

[-- Attachment #1: 0002-tracing-x86-Don-t-use-mcount-in-kvmclock.c.patch --]
[-- Type: text/plain, Size: 937 bytes --]

From: Steven Rostedt <srostedt@redhat.com>

The guest can use the paravirt clock in kvmclock.c which is used
by sched_clock(), which in turn is used by the tracing mechanism
for timestamps, which leads to infinite recursion.

Disable mcount/tracing for kvmclock.o.

Cc: stable@kernel.org
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Avi Kivity <avi@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 arch/x86/kernel/Makefile |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 882bbff..fedf32a 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -12,6 +12,7 @@ CFLAGS_REMOVE_tsc.o = -pg
 CFLAGS_REMOVE_rtc.o = -pg
 CFLAGS_REMOVE_paravirt-spinlocks.o = -pg
 CFLAGS_REMOVE_pvclock.o = -pg
+CFLAGS_REMOVE_kvmclock.o = -pg
 CFLAGS_REMOVE_ftrace.o = -pg
 CFLAGS_REMOVE_early_printk.o = -pg
 endif
-- 
1.7.1

Re: [PATCH 0/2] [GIT PULL][v2.6.36] tracing: fixes for tracing virt guests

[Ingo Molnar]

* Steven Rostedt <rostedt@goodmis.org> wrote:

> Ingo,
> 
> I actually did these fixes back in July for RHEL, but forgot about
> them for mainline :-(
> 
> Jeremy hit the same bug and set me a fix. It was only part of what
> I did in July, so I pulled in his fix and added the second part.
> 
> Please pull the latest tip/perf/urgent tree, which can be found at:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git
> tip/perf/urgent
> 
> 
> Jeremy Fitzhardinge (1):
>       tracing/x86: Don't use mcount in pvclock.c
> 
> Steven Rostedt (1):
>       tracing/x86: Don't use mcount in kvmclock.c
> 
> ----
>  arch/x86/kernel/Makefile |    2 ++
>  1 files changed, 2 insertions(+), 0 deletions(-)

Pulled, thanks Steve!

	Ingo