From 60916a9382e88fbf5e54fd36a3e658efd7ab7bed Mon Sep 17 00:00:00 2001
From: Will Deacon <will.deacon@arm.com>
Date: Thu, 16 Aug 2012 18:14:14 +0100
Subject: [PATCH 1/3] tracing/syscalls: Fix perf syscall tracing when
 syscall_nr == -1

syscall_get_nr can return -1 in the case that the task is not executing
a system call.

This patch fixes perf_syscall_{enter,exit} to check that the syscall
number is valid before using it as an index into a bitmap.

Link: http://lkml.kernel.org/r/1345137254-7377-1-git-send-email-will.deacon@arm.com

Cc: Jason Baron <jbaron@redhat.com>
Cc: Wade Farnsworth <wade_farnsworth@mentor.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 kernel/trace/trace_syscalls.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 60e4d7875672..6b245f64c8dd 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -506,6 +506,8 @@ static void perf_syscall_enter(void *ignore, struct pt_regs *regs, long id)
 	int size;
 
 	syscall_nr = syscall_get_nr(current, regs);
+	if (syscall_nr < 0)
+		return;
 	if (!test_bit(syscall_nr, enabled_perf_enter_syscalls))
 		return;
 
@@ -580,6 +582,8 @@ static void perf_syscall_exit(void *ignore, struct pt_regs *regs, long ret)
 	int size;
 
 	syscall_nr = syscall_get_nr(current, regs);
+	if (syscall_nr < 0)
+		return;
 	if (!test_bit(syscall_nr, enabled_perf_exit_syscalls))
 		return;
 

From c7a3a88c938fbe3d70c2278e082b80eb830d1c58 Mon Sep 17 00:00:00 2001
From: Oleg Nesterov <oleg@redhat.com>
Date: Sun, 19 Aug 2012 19:10:42 +0200
Subject: [PATCH 2/3] uprobes: Fix mmap_region()'s mm->mm_rb corruption if
 uprobe_mmap() fails

This patch fixes:

  https://bugzilla.redhat.com/show_bug.cgi?id=843640

If mmap_region()->uprobe_mmap() fails, unmap_and_free_vma path
does unmap_region() but does not remove the soon-to-be-freed vma
from rb tree. Actually there are more problems but this is how
William noticed this bug.

Perhaps we could do do_munmap() + return in this case, but in
fact it is simply wrong to abort if uprobe_mmap() fails. Until
at least we move the !UPROBE_COPY_INSN code from
install_breakpoint() to uprobe_register().

For example, uprobe_mmap()->install_breakpoint() can fail if the
probed insn is not supported (remember, uprobe_register()
succeeds if nobody mmaps inode/offset), mmap() should not fail
in this case.

dup_mmap()->uprobe_mmap() is wrong too by the same reason,
fork() can race with uprobe_register() and fail for no reason if
it wins the race and does install_breakpoint() first.

And, if nothing else, both mmap_region() and dup_mmap() return
success if uprobe_mmap() fails. Change them to ignore the error
code from uprobe_mmap().

Reported-and-tested-by: William Cohen <wcohen@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> # v3.5
Cc: Anton Arapov <anton@redhat.com>
Cc: William Cohen <wcohen@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20120819171042.GB26957@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/fork.c | 4 ++--
 mm/mmap.c     | 5 ++---
 2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/kernel/fork.c b/kernel/fork.c
index 3bd2280d79f6..2c8857e12855 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -455,8 +455,8 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
 		if (retval)
 			goto out;
 
-		if (file && uprobe_mmap(tmp))
-			goto out;
+		if (file)
+			uprobe_mmap(tmp);
 	}
 	/* a new mm has just been created */
 	arch_dup_mmap(oldmm, mm);
diff --git a/mm/mmap.c b/mm/mmap.c
index e3e86914f11a..52e08fc9186d 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1356,9 +1356,8 @@ out:
 	} else if ((flags & MAP_POPULATE) && !(flags & MAP_NONBLOCK))
 		make_pages_present(addr, addr + len);
 
-	if (file && uprobe_mmap(vma))
-		/* matching probes but cannot insert */
-		goto unmap_and_free_vma;
+	if (file)
+		uprobe_mmap(vma);
 
 	return addr;
 

From 3ab484b8622b7b890ca8d2ab5ee034c217ee4eeb Mon Sep 17 00:00:00 2001
From: Arnaldo Carvalho de Melo <acme@redhat.com>
Date: Tue, 14 Aug 2012 14:17:30 -0300
Subject: [PATCH 3/3] perf tools: Add missing files to build the python binding
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Changeset 0f6a3015:
"perf tools: Support user regs and stack in sample parsing"

uses hweight_long in evsel.c, so we need to drag util/hweight.c
to the python binding.

Ditto for ee8dd3c:
"perf tools: Change strlist to use the new rblist"

where we need to add util/rblist.c.

Now twatch.py works again:

 # export PYTHONPATH=~acme/git/build/perf/python/
 # ~acme/git/linux/tools/perf/python/twatch.py
 cpu:  4, pid: 23639, tid: 23639 { type: fork, pid: 30659, ppid: 23639, tid: 30659, ptid: 23639, time: 36287872076780}
 cpu:  5, pid: 30659, tid: 30659 { type: comm, pid: 30659, tid: 30659, comm: ls }
 cpu:  5, pid: 30659, tid: 30659 { type: exit, pid: 30659, ppid: 30659, tid: 30659, ptid: 30659, time: 36287873681539}
 cpu:  4, pid: 23639, tid: 23639 { type: fork, pid: 30660, ppid: 23639, tid: 30660, ptid: 23639, time: 36291720420480}
 cpu:  5, pid: 30659, tid: 30659 { type: exit, pid: 30659, ppid: 30659, tid: 30659, ptid: 30659, time: 36287873685714}
 cpu:  5, pid: 30660, tid: 30660 { type: comm, pid: 30660, tid: 30660, comm: git }
 ^C
 KeyboardInterrupt

Reported-by: Jérôme Carretero <cJ-ko@zougloub.eu>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-gmq82zp5blin9aml9g5tzokr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
 tools/perf/util/python-ext-sources | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tools/perf/util/python-ext-sources b/tools/perf/util/python-ext-sources
index 2884e67ee625..213362850abd 100644
--- a/tools/perf/util/python-ext-sources
+++ b/tools/perf/util/python-ext-sources
@@ -10,10 +10,12 @@ util/ctype.c
 util/evlist.c
 util/evsel.c
 util/cpumap.c
+util/hweight.c
 util/thread_map.c
 util/util.c
 util/xyarray.c
 util/cgroup.c
 util/debugfs.c
+util/rblist.c
 util/strlist.c
 ../../lib/rbtree.c