From 969558371bf926258241727ebb994f516f2e6f61 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Mon, 27 Aug 2018 11:12:27 +0200 Subject: [PATCH] perf/hw_breakpoint: Enable breakpoint in modify_user_hw_breakpoint Currently we enable the breakpoint back only if the breakpoint modification was successful. If it fails we can leave the breakpoint in disabled state with attr->disabled == 0. We can safely enable the breakpoint back for both the fail and success paths by checking the bp->attr.disabled, which either holds the new 'requested' disabled state or the original breakpoint state. Suggested-by: Oleg Nesterov Signed-off-by: Jiri Olsa Acked-by: Frederic Weisbecker Acked-by: Oleg Nesterov Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: David Ahern Cc: Milind Chabbi Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20180827091228.2878-5-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- kernel/events/hw_breakpoint.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c index 3e560d7609fd..d6b56180827c 100644 --- a/kernel/events/hw_breakpoint.c +++ b/kernel/events/hw_breakpoint.c @@ -523,13 +523,11 @@ int modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *att perf_event_disable(bp); err = modify_user_hw_breakpoint_check(bp, attr, false); - if (err) - return err; - if (!attr->disabled) + if (!bp->attr.disabled) perf_event_enable(bp); - return 0; + return err; } EXPORT_SYMBOL_GPL(modify_user_hw_breakpoint); -- 2.30.2