#2004·moonlight-qt

Linux: SIGSEGV with fatal X11 error during VA-API initialization on Intel/AMD under Hyprland

Author: putueddyCreated Sep 8, 2026Updated Sep 10, 2026

Repeated SIGSEGV on Intel/AMD hardware under Hyprland/Xwayland while a worker thread handles a fatal X11 error during VA-API initialization.

Moonlight 6.1.0-7 (Arch package, /usr/bin/moonlight) crashed twice on 2026-09-08, at 09:07:17 and 11:29:44 UTC+7. Both systemd-coredump records show a worker thread entering the fatal X11 I/O error handler during VA-API initialization and calling exit(), while the main Qt GUI thread continues processing events. The final SIGSEGV occurs in different libraries in the two dumps.

In the later crash, the worker stack is:

vaInitialize
  -> libva-x11 initialization / va_isDRI2Connected
  -> VA_DRI2QueryExtension
  -> XextAddDisplay / XInitExtension / XQueryExtension
  -> _XGetRequest / _XFlush / _XIOError
  -> _XDefaultIOError
  -> exit
  -> Qt Quick cleanup / QImage::~QImage / QImageData::~QImageData
  -> munmap

At the same time the main thread is in QSGPlainTexture::commitTextureOperations, reached through Qt Quick scene-graph rendering, with the actual fault in libgallium-26.2.1-arch1.1.so + 0x5cc059 (invalid read at address 0x4).

The earlier crash also has vaInitialize -> VA_DRI2QueryExtension -> XQueryExtension -> _XIOError -> _XDefaultIOError -> exit on a worker thread, including a nested fatal X11 error during SDL cursor cleanup. Its main-thread SIGSEGV is in libQt6Gui.so.6 + 0xe7970, called by QPointingDevice::primaryPointingDevice and QQuickWindow::mouseGrabberItem during Qt Quick event processing.

This suggests cleanup overlapping ongoing GUI work after an X11 I/O failure. It does not establish why the X11 connection failed or which component originally caused it. Possibly related: #1680, closed with commits 54283ce0a15b6ec50945b7625f4c601bd50e2796 and 4d6196c3d376171c2111a2eb64ba1ef54d3135cd. The hardware and packaging differ; equivalence has not been confirmed. This is not a claim of a regression after the linked fixes: their presence in the installed distro build has not been established and a build containing them has not been tested.

Client PC details

Arch Linux / Omarchy, Hyprland; Qt XCB platform present in the core
moonlight-qt 6.1.0-7
mesa 1:26.2.1-1
qt6-base 6.11.2-2; qt6-declarative 6.11.2-1
libva 2.24.1-1
sdl2-compat 2.32.70-1; sdl3 3.4.14-1
xorg-xwayland 24.1.13-1
linux-t2 7.1.8.arch1-3
Intel UHD Graphics 630 (i915) and AMD Radeon Pro 555X (amdgpu); the GPU actually used by the crashing code has not been established

No OOM kill or GPU reset was logged around the crash. Exact user interaction, server details, and a reliable reproduction sequence are not available from the core. The stacks establish that VA-API initialization was in flight. Software decoding has been suggested as a diagnostic test but has not been tested for these crashes. Debug-symbol retrieval failed during diagnosis, so unresolved frames below are retained as recorded.

Reproduction and missing context

The application was launched as moonlight. Two crashes were recorded during ordinary use; exact interaction immediately before the crash was not captured. No controlled reproduction has been performed. Expected behavior is successful initialization or a handled error, without SIGSEGV.

Affected game, server OS/GPU/Sunshine version, and behavior on other clients: not established during diagnosis. Settings have not been reset and default-settings behavior is untested. No application log from these exact runs was located; available older logs were excluded to avoid conflating sessions.

Crash diagnostics

Selected original systemd-coredump stacks follow (metadata identifying the local account/host is omitted; no raw process-memory dump is attached).

PID 275905, thread 275905

#0  0x00007ff0ccbcc059 n/a (libgallium-26.2.1-arch1.1.so + 0x5cc059)
#1  0x00007ff0cc6fb559 n/a (libgallium-26.2.1-arch1.1.so + 0xfb559)
#2  0x00007ff0cc75dde8 n/a (libgallium-26.2.1-arch1.1.so + 0x15dde8)
#3  0x00007ff0cc75de32 n/a (libgallium-26.2.1-arch1.1.so + 0x15de32)
#4  0x00007ff0cc75dfba n/a (libgallium-26.2.1-arch1.1.so + 0x15dfba)
#5  0x00007ff0cc75e28b n/a (libgallium-26.2.1-arch1.1.so + 0x15e28b)
#6  0x00007ff0cc75e458 n/a (libgallium-26.2.1-arch1.1.so + 0x15e458)
#7  0x00007ff0cc71fa20 n/a (libgallium-26.2.1-arch1.1.so + 0x11fa20)
#8  0x00007ff0cc722281 n/a (libgallium-26.2.1-arch1.1.so + 0x122281)
#9  0x00007ff10aff0aea n/a (libQt6Gui.so.6 + 0x5f0aea)
#10 0x00007ff0fbb5c0b0 _ZN15QSGPlainTexture23commitTextureOperationsEP4QRhiP23QRhiResourceUpdateBatch (libQt6Quick.so.6 + 0x35c0b0)
#11 0x00007ff0fbb673db _ZN33QSGOpaqueTextureMaterialRhiShader18updateSampledImageERN17QSGMaterialShader11RenderStateEiPP10QSGTextureP11QSGMaterialS7_ (libQt6Quick.so.6 + 0x3673db)
#12 0x00007ff0fbab119e _ZN16QSGBatchRenderer8Renderer25updateMaterialDynamicDataEPNS_19ShaderManagerShaderERN17QSGMaterialShader11RenderStateEP11QSGMaterialPKNS_5BatchEPNS_7ElementEiiPc (libQt6Quick.so.6 + 0x2b119e)
#13 0x00007ff0fbac67a5 n/a (libQt6Quick.so.6 + 0x2c67a5)
#14 0x00007ff0fbabc3d7 _ZN16QSGBatchRenderer8Renderer17prepareRenderPassEPNS0_17RenderPassContextE (libQt6Quick.so.6 + 0x2bc3d7)
#15 0x00007ff0fbabdd5d _ZN16QSGBatchRenderer8Renderer6renderEv (libQt6Quick.so.6 + 0x2bdd5d)
#16 0x00007ff0fbad97a1 n/a (libQt6Quick.so.6 + 0x2d97a1)
#17 0x00007ff0fba653d5 _ZN19QQuickWindowPrivate16renderSceneGraphEv (libQt6Quick.so.6 + 0x2653d5)
#18 0x00007ff0fbb2903e n/a (libQt6Quick.so.6 + 0x32903e)
#19 0x00007ff0fba67584 _ZN12QQuickWindow5eventEP6QEvent (libQt6Quick.so.6 + 0x267584)
#20 0x00007ff109b822b8 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x1822b8)
#21 0x00007ff10ac01876 _ZN15QPlatformWindow20deliverUpdateRequestEv (libQt6Gui.so.6 + 0x201876)
#22 0x00007ff10abfef65 _ZN15QPlatformWindow11windowEventEP6QEvent (libQt6Gui.so.6 + 0x1fef65)
#23 0x00007ff10aba995c _ZN15QGuiApplication6notifyEP7QObjectP6QEvent (libQt6Gui.so.6 + 0x1a995c)
#24 0x00007ff109b822b8 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x1822b8)
#25 0x00007ff109d648f5 _ZN14QTimerInfoList14activateTimersEv (libQt6Core.so.6 + 0x3648f5)
#26 0x00007ff109e9a439 n/a (libQt6Core.so.6 + 0x49a439)
#27 0x00007ff1084fec76 n/a (libglib-2.0.so.0 + 0x61c76)
#28 0x00007ff108500ed7 n/a (libglib-2.0.so.0 + 0x63ed7)
#29 0x00007ff108501055 g_main_context_iteration (libglib-2.0.so.0 + 0x64055)
#30 0x00007ff109e96f32 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt6Core.so.6 + 0x496f32)
#31 0x0000560271717b40 n/a (moonlight + 0xb5b40)
#32 0x0000560271719fa2 n/a (moonlight + 0xb7fa2)
#33 0x00007ff10a766663 n/a (libQt6Qml.so.6 + 0x366663)
#34 0x00007ff10a6016bb n/a (libQt6Qml.so.6 + 0x2016bb)

PID 275905, thread 317391

#0  0x00007ff10931cdeb __munmap (libc.so.6 + 0x11cdeb)
#1  0x00007ff1092a6397 n/a (libc.so.6 + 0xa6397)
#2  0x00007ff10ab369ea _ZN10QImageDataD1Ev (libQt6Gui.so.6 + 0x1369ea)
#3  0x00007ff10ab36d76 _ZN6QImageD2Ev (libQt6Gui.so.6 + 0x136d76)
#4  0x00007ff0fbbc53f5 n/a (libQt6Quick.so.6 + 0x3c53f5)
#5  0x00007ff0fbbc855b n/a (libQt6Quick.so.6 + 0x3c855b)
#6  0x00007ff0fbbcc9cd n/a (libQt6Quick.so.6 + 0x3cc9cd)
#7  0x00007ff109240fbf n/a (libc.so.6 + 0x40fbf)
#8  0x00007ff10924109e exit (libc.so.6 + 0x4109e)
#9  0x00007ff10d6fa8e6 _XDefaultIOError (libX11.so.6 + 0x3c8e6)
#10 0x00007ff10d6fda4c _XIOError (libX11.so.6 + 0x3fa4c)
#11 0x00007ff10d7030c9 _XFlush (libX11.so.6 + 0x450c9)
#12 0x00007ff10d70339d _XGetRequest (libX11.so.6 + 0x4539d)
#13 0x00007ff10d6f5a48 XQueryExtension (libX11.so.6 + 0x37a48)
#14 0x00007ff10d6e8acd XInitExtension (libX11.so.6 + 0x2aacd)
#15 0x00007ff10942c485 XextAddDisplay (libXext.so.6 + 0x6485)
#16 0x00007ff10e3c0706 VA_DRI2QueryExtension (libva-x11.so.2 + 0x2706)
#17 0x00007ff10e3c0bf9 va_isDRI2Connected (libva-x11.so.2 + 0x2bf9)
#18 0x00007ff10e3c0e03 n/a (libva-x11.so.2 + 0x2e03)
#19 0x00007ff10dc3e92a vaInitialize (libva.so.2 + 0xa92a)
#20 0x00005602717027dd n/a (moonlight + 0xa07dd)
#21 0x00005602716f5fa7 n/a (moonlight + 0x93fa7)
#22 0x00005602716f7670 n/a (moonlight + 0x95670)
#23 0x00005602716f81b9 n/a (moonlight + 0x961b9)
#24 0x00005602716dedc0 n/a (moonlight + 0x7cdc0)
#25 0x00005602716e400a n/a (moonlight + 0x8200a)
#26 0x00007ff109d721eb n/a (libQt6Core.so.6 + 0x3721eb)
#27 0x00007ff1092980a2 n/a (libc.so.6 + 0x980a2)
#28 0x00007ff10932080c n/a (libc.so.6 + 0x12080c)

PID 22997, thread 22997

#0  0x00007f1c158e7970 n/a (libQt6Gui.so.6 + 0xe7970)
#1  0x00007f1c15a0b96e _ZN15QPointingDevice21primaryPointingDeviceERK7QString (libQt6Gui.so.6 + 0x20b96e)
#2  0x00007f1c0686596f _ZNK12QQuickWindow16mouseGrabberItemEv (libQt6Quick.so.6 + 0x26596f)
#3  0x00007f1c069b0939 _ZN26QQuickDeliveryAgentPrivate27flushFrameSynchronousEventsEP12QQuickWindow (libQt6Quick.so.6 + 0x3b0939)
#4  0x00007f1c06928d3c n/a (libQt6Quick.so.6 + 0x328d3c)
#5  0x00007f1c06867584 _ZN12QQuickWindow5eventEP6QEvent (libQt6Quick.so.6 + 0x267584)
#6  0x00007f1c149822b8 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x1822b8)
#7  0x00007f1c15a01876 _ZN15QPlatformWindow20deliverUpdateRequestEv (libQt6Gui.so.6 + 0x201876)
#8  0x00007f1c159fef65 _ZN15QPlatformWindow11windowEventEP6QEvent (libQt6Gui.so.6 + 0x1fef65)
#9  0x00007f1c159a995c _ZN15QGuiApplication6notifyEP7QObjectP6QEvent (libQt6Gui.so.6 + 0x1a995c)
#10 0x00007f1c149822b8 _ZN16QCoreApplication15notifyInternal2EP7QObjectP6QEvent (libQt6Core.so.6 + 0x1822b8)
#11 0x00007f1c14b648f5 _ZN14QTimerInfoList14activateTimersEv (libQt6Core.so.6 + 0x3648f5)
#12 0x00007f1c14c9a439 n/a (libQt6Core.so.6 + 0x49a439)
#13 0x00007f1c1371dc76 n/a (libglib-2.0.so.0 + 0x61c76)
#14 0x00007f1c1371fed7 n/a (libglib-2.0.so.0 + 0x63ed7)
#15 0x00007f1c13720055 g_main_context_iteration (libglib-2.0.so.0 + 0x64055)
#16 0x00007f1c14c96f32 _ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE (libQt6Core.so.6 + 0x496f32)
#17 0x0000556814045b40 n/a (moonlight + 0xb5b40)
#18 0x0000556814047fa2 n/a (moonlight + 0xb7fa2)
#19 0x00007f1c15566663 n/a (libQt6Qml.so.6 + 0x366663)
#20 0x00007f1c154016bb n/a (libQt6Qml.so.6 + 0x2016bb)
#21 0x00007f1c15403508 _ZN3QV413QObjectMethod11callPreciseERK18QQmlObjectOrGadgetRK16QQmlPropertyDataPNS_15ExecutionEngineEPNS_8CallDataEN11QMetaObject4CallE (libQt6Qml.so.6 + 0x203508)
#22 0x00007f1c15405855 _ZNK3QV413QObjectMethod12callInternalEPKNS_5ValueES3_i (libQt6Qml.so.6 + 0x205855)
#23 0x00007f1c154642c8 n/a (libQt6Qml.so.6 + 0x2642c8)
#24 0x00007f1c15470fd2 n/a (libQt6Qml.so.6 + 0x270fd2)
#25 0x00007f1c153a8874 n/a (libQt6Qml.so.6 + 0x1a8874)
#26 0x00007f1c153aee55 _ZN3QV48Function4callEP7QObjectPPvPK9QMetaTypeiPNS_16ExecutionContextE (libQt6Qml.so.6 + 0x1aee55)
#27 0x00007f1c1551f908 _ZN24QQmlJavaScriptExpression8evaluateEPPvPK9QMetaTypei (libQt6Qml.so.6 + 0x31f908)
#28 0x00007f1c154ade0b _ZN25QQmlBoundSignalExpression8evaluateEPPv (libQt6Qml.so.6 + 0x2ade0b)
#29 0x00007f1c154b3939 n/a (libQt6Qml.so.6 + 0x2b3939)
#30 0x00007f1c1554cc20 _ZN12QQmlNotifier10emitNotifyEP20QQmlNotifierEndpointPPv (libQt6Qml.so.6 + 0x34cc20)
#31 0x00007f1c149eef5f n/a (libQt6Core.so.6 + 0x1eef5f)
#32 0x00007f1c15514f53 _ZN20QQmlIncubatorPrivate8incubateER26QQmlInstantiationInterrupt (libQt6Qml.so.6 + 0x314f53)
#33 0x00007f1c15515ce1 _ZN24QQmlIncubationController11incubateForEi (libQt6Qml.so.6 + 0x315ce1)
#34 0x00007f1c06858490 n/a (libQt6Quick.so.6 + 0x258490)

PID 22997, thread 29587

#0  0x00007f1c074dc670 n/a (libglslang.so.16 + 0x2dc670)
#1  0x00007f1c14040a21 __cxa_finalize (libc.so.6 + 0x40a21)
#2  0x00007f1c07215d08 n/a (libglslang.so.16 + 0x15d08)
#3  0x00007f1c191d2012 n/a (ld-linux-x86-64.so.2 + 0x2012)
#4  0x00007f1c191d60ae n/a (ld-linux-x86-64.so.2 + 0x60ae)
#5  0x00007f1c14040fbf n/a (libc.so.6 + 0x40fbf)
#6  0x00007f1c1404109e exit (libc.so.6 + 0x4109e)
#7  0x00007f1c168fa8e6 _XDefaultIOError (libX11.so.6 + 0x3c8e6)
#8  0x00007f1c168fda4c _XIOError (libX11.so.6 + 0x3fa4c)
#9  0x00007f1c169030c9 _XFlush (libX11.so.6 + 0x450c9)
#10 0x00007f1c1690339d _XGetRequest (libX11.so.6 + 0x4539d)
#11 0x00007f1c168d8f92 XFreeCursor (libX11.so.6 + 0x1af92)
#12 0x00007f1c0239eace n/a (libSDL3.so.0 + 0x19eace)
#13 0x00007f1c0225b656 n/a (libSDL3.so.0 + 0x5b656)
#14 0x00007f1c022608c0 n/a (libSDL3.so.0 + 0x608c0)
#15 0x00007f1c0221db0e n/a (libSDL3.so.0 + 0x1db0e)
#16 0x00007f1c0221e101 n/a (libSDL3.so.0 + 0x1e101)
#17 0x00007f1c19055f96 n/a (libSDL2-2.0.so.0 + 0x2af96)
#18 0x00007f1c14040fbf n/a (libc.so.6 + 0x40fbf)
#19 0x00007f1c1404109e exit (libc.so.6 + 0x4109e)
#20 0x00007f1c168fa8e6 _XDefaultIOError (libX11.so.6 + 0x3c8e6)
#21 0x00007f1c168fda4c _XIOError (libX11.so.6 + 0x3fa4c)
#22 0x00007f1c169030c9 _XFlush (libX11.so.6 + 0x450c9)
#23 0x00007f1c1690339d _XGetRequest (libX11.so.6 + 0x4539d)
#24 0x00007f1c168f5a48 XQueryExtension (libX11.so.6 + 0x37a48)
#25 0x00007f1c168e8acd XInitExtension (libX11.so.6 + 0x2aacd)
#26 0x00007f1c1218e485 XextAddDisplay (libXext.so.6 + 0x6485)
#27 0x00007f1c1900c706 VA_DRI2QueryExtension (libva-x11.so.2 + 0x2706)
#28 0x00007f1c1900cbf9 va_isDRI2Connected (libva-x11.so.2 + 0x2bf9)
#29 0x00007f1c1900ce03 n/a (libva-x11.so.2 + 0x2e03)
#30 0x00007f1c18fbc92a vaInitialize (libva.so.2 + 0xa92a)
#31 0x00005568140307dd n/a (moonlight + 0xa07dd)
#32 0x0000556814023fa7 n/a (moonlight + 0x93fa7)
#33 0x0000556814025670 n/a (moonlight + 0x95670)
#34 0x00005568140261b9 n/a (moonlight + 0x961b9)
#35 0x000055681400cdc0 n/a (moonlight + 0x7cdc0)
#36 0x000055681401200a n/a (moonlight + 0x8200a)
#37 0x00007f1c14b721eb n/a (libQt6Core.so.6 + 0x3721eb)
#38 0x00007f1c140980a2 n/a (libc.so.6 + 0x980a2)
#39 0x00007f1c1412080c n/a (libc.so.6 + 0x12080c)

Source: moonlight-stream/moonlight-qt

View original on GitHub View discussion on GitHub