Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fixes from Ingo Molnar:
 "Mostly tooling fixes, but also breakpoint and x86 PMU driver fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  perf tools: Fix maps__find_symbol_by_name()
  tools headers uapi: Update tools's copy of linux/if_link.h
  tools headers uapi: Update tools's copy of linux/vhost.h
  tools headers uapi: Update tools's copies of kvm headers
  tools headers uapi: Update tools's copy of drm/drm.h
  tools headers uapi: Update tools's copy of asm-generic/unistd.h
  tools headers uapi: Update tools's copy of linux/perf_event.h
  perf/core: Force USER_DS when recording user stack data
  perf/UAPI: Clearly mark __PERF_SAMPLE_CALLCHAIN_EARLY as internal use
  perf/x86/intel: Add support/quirk for the MISPREDICT bit on Knights Landing CPUs
  perf annotate: Fix parsing aarch64 branch instructions after objdump update
  perf probe powerpc: Ignore SyS symbols irrespective of endianness
  perf event-parse: Use fixed size string for comms
  perf util: Fix bad memory access in trace info.
  perf tools: Streamline bpf examples and headers installation
  perf evsel: Fix potential null pointer dereference in perf_evsel__new_idx()
  perf arm64: Fix include path for asm-generic/unistd.h
  perf/hw_breakpoint: Simplify breakpoint enable in perf_event_modify_breakpoint
  perf/hw_breakpoint: Enable breakpoint in modify_user_hw_breakpoint
  perf/hw_breakpoint: Remove superfluous bp->attr.disabled = 0
  ...

2 files changed, 13 insertions, 15 deletions

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 2a62b96600ad..c80549bf82c6 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -2867,16 +2867,11 @@ static int perf_event_modify_breakpoint(struct perf_event *bp,
         _perf_event_disable(bp);
 
         err = modify_user_hw_breakpoint_check(bp, attr, true);
-        if (err) {
-                if (!bp->attr.disabled)
-                        _perf_event_enable(bp);
 
-                return err;
-        }
-
-        if (!attr->disabled)
+        if (!bp->attr.disabled)
                 _perf_event_enable(bp);
-        return 0;
+
+        return err;
 }
 
 static int perf_event_modify_attr(struct perf_event *event,
@@ -5948,6 +5943,7 @@ perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size,
                 unsigned long sp;
                 unsigned int rem;
                 u64 dyn_size;
+                mm_segment_t fs;
 
                 /*
                  * We dump:
@@ -5965,7 +5961,10 @@ perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size,
 
                 /* Data. */
                 sp = perf_user_stack_pointer(regs);
+                fs = get_fs();
+                set_fs(USER_DS);
                 rem = __output_copy_user(handle, (void *) sp, dump_size);
+                set_fs(fs);
                 dyn_size = dump_size - rem;
 
                 perf_output_skip(handle, rem);
diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c
index b3814fce5ecb..d6b56180827c 100644
--- a/kernel/events/hw_breakpoint.c
+++ b/kernel/events/hw_breakpoint.c
@@ -509,6 +509,8 @@ modify_user_hw_breakpoint_check(struct perf_event *bp, struct perf_event_attr *a
  */
 int modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *attr)
 {
+        int err;
+
         /*
          * modify_user_hw_breakpoint can be invoked with IRQs disabled and hence it
          * will not be possible to raise IPIs that invoke __perf_event_disable.
@@ -520,15 +522,12 @@ int modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *att
         else
                 perf_event_disable(bp);
 
-        if (!attr->disabled) {
-                int err = modify_user_hw_breakpoint_check(bp, attr, false);
+        err = modify_user_hw_breakpoint_check(bp, attr, false);
 
-                if (err)
-                        return err;
+        if (!bp->attr.disabled)
                 perf_event_enable(bp);
-                bp->attr.disabled = 0;
-        }
-        return 0;
+
+        return err;
 }
 EXPORT_SYMBOL_GPL(modify_user_hw_breakpoint);