diff options
Diffstat (limited to 'services/input/EventHub.cpp')
| -rw-r--r-- | services/input/EventHub.cpp | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/services/input/EventHub.cpp b/services/input/EventHub.cpp index f80ac18..1c9520d 100644 --- a/services/input/EventHub.cpp +++ b/services/input/EventHub.cpp @@ -787,6 +787,40 @@ size_t EventHub::getEvents(int timeoutMillis, RawEvent* buffer, size_t bufferSiz event->when = nsecs_t(iev.time.tv_sec) * 1000000000LL + nsecs_t(iev.time.tv_usec) * 1000LL; ALOGV("event time %lld, now %lld", event->when, now); + + // Bug 7291243: Add a guard in case the kernel generates timestamps + // that appear to be far into the future because they were generated + // using the wrong clock source. + // + // This can happen because when the input device is initially opened + // it has a default clock source of CLOCK_REALTIME. Any input events + // enqueued right after the device is opened will have timestamps + // generated using CLOCK_REALTIME. We later set the clock source + // to CLOCK_MONOTONIC but it is already too late. + // + // Invalid input event timestamps can result in ANRs, crashes and + // and other issues that are hard to track down. We must not let them + // propagate through the system. + // + // Log a warning so that we notice the problem and recover gracefully. + if (event->when >= now + 10 * 1000000000LL) { + // Double-check. Time may have moved on. + nsecs_t time = systemTime(SYSTEM_TIME_MONOTONIC); + if (event->when > time) { + ALOGW("An input event from %s has a timestamp that appears to " + "have been generated using the wrong clock source " + "(expected CLOCK_MONOTONIC): " + "event time %lld, current time %lld, call time %lld. " + "Using current time instead.", + device->path.string(), event->when, time, now); + event->when = time; + } else { + ALOGV("Event time is ok but failed the fast path and required " + "an extra call to systemTime: " + "event time %lld, current time %lld, call time %lld.", + event->when, time, now); + } + } #else event->when = now; #endif |