Nexus 4: Resuming with multiple system compositors running leads one of them to crash ("error during hwc prepare()")

[Daniel van Vugt]

Nexus 4: Mir server crashes on resume ("error during hwc prepare()")

Test case:
   1. mir_demo_server_shell
   2. mir_demo_client_egltriangle
   3. Press the power button to sleep
   4. Press the power button again to wake up

Expected: Rendering continues on screen after wakeup
Observed:
ERROR: /home/dan/bzr/mir/dev/src/platform/graphics/android/real_hwc_wrapper.cpp(60): Throw in function virtual void mir::graphics::android::RealHwcWrapper::set(hwc_display_contents_1_t&) const
Dynamic exception type: N5boost16exception_detail10clone_implINS0_19error_info_injectorISt13runtime_errorEEEE
std::exception::what: error during hwc prepare(). rc = ffffffff

Update: I just found this is happening because unity-system-compositor is still running. If I freeze USC (kill -STOP) then the problem goes away.

[Daniel van Vugt (vanvugt)]

Hmm, was this fixed with bug 1474891?

[Michał Sawicz (saviq)]

Syncing task from Mir.