SIGBUS crash in RenderHal_Initialize using VA-API with Arc B580 (Battlemage G21)

[butchermustdie]

Describe the bug

Running vainfo on Intel Arc B580 (Battlemage G21) with the iHD driver results in a SIGBUS (Bus error) crash during heap initialization in RenderHal_Initialize.

The issue appears in memset() during state heap interface setup.

---

To Reproduce

Steps to reproduce the behavior:

1. Use Ubuntu 25.04 with latest kernel and Mesa stack.

2. Install intel-media-driver with iHD support.

3. Ensure LIBVA_DRIVER_NAME=iHD and run:

   vainfo

4. Observe a SIGBUS crash.

---

Expected behavior

vainfo should detect and list supported VA-API profiles using the iHD driver.

---

Stack trace (from GDB)

Program received signal SIGBUS, Bus error.
__memset_avx2_unaligned_erms () at ../sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S:210

#0  __memset_avx2_unaligned_erms ()
#1  0x00007ffff5e45973 in XMHW_STATE_HEAP_INTERFACE::InitializeInterface (
    this=0x555555604230, StateHeapSettings=...)
    at /media-driver/media_softlet/agnostic/common/hw/mhw_state_heap.cpp:1083
#2  0x00007ffff5e45d27 in Mhw_StateHeapInterface_Create (
    ppStateHeapInterface=<optimised out>, StateHeapSettings=...)
    at /media-driver/media_softlet/agnostic/common/hw/mhw_state_heap.cpp:680
#3  0x00007ffff5d8676b in mhw::render::Impl<mhw::render::xe2_hpg_next::Cmd>::AllocateHeaps (this=<optimised out>, stateHeapSettings=...)
    at /media-driver/media_softlet/agnostic/common/hw/mhw_render_impl.h:167
#4  0x00007ffff5d39dcf in XRenderHal_Platform_Interface_Next::AllocateHeaps (
    this=<optimised out>, pRenderHal=<optimised out>, MhwStateHeapSettings=...)
    at /media-driver/media_softlet/agnostic/common/renderhal/renderhal_platform_interface_next.cpp:807
#5  0x00007ffff5d36b04 in RenderHal_AllocateStateHeaps (
    pRenderHal=0x5555556017b0, pSettings=0x555555601858)
    at /media-driver/media_softlet/agnostic/common/renderhal/renderhal.cpp:1499
#6  0x00007ffff5d35005 in RenderHal_Initialize (pRenderHal=0x5555556017b0, ...

---

Environment

• GPU: Intel Arc B580 (Battlemage G21)
• Kernel: 6.15.0-rc4+
• OS: Ubuntu 25.04 (plucky)
• Media driver version: latest build from source (May 4, 2025)
• libva version: 2.22.0
• vainfo: crashes with SIGBUS
• Mesa version: 25.0.3

---

Additional context

• The crash happens regardless of Wayland/X11.
• Mesa VA driver (mesa_drv_video.so) does not support this hardware.
• User is in render group, permissions are correct.

---

Suggested label: bug, Battlemage, Arc, SIGBUS, heap allocation, VAAPI

---

[Reabstraction]

reabs@reabs-arch:~ » gdb vainfo
GNU gdb (GDB) 16.3
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Reading symbols from vainfo...

This GDB supports auto-downloading debuginfo from the following URLs:
  <https://debuginfod.archlinux.org>
  <https://debuginfod.alhp.dev>
Enable debuginfod for this session? (y or [n]) y
Debuginfod has been enabled.
To make this setting permanent, add 'set debuginfod enabled on' to .gdbinit.
Downloading separate debug info for /usr/bin/vainfo
Reading symbols from /home/reabs/.cache/debuginfod_client/4e434dd2fc87ae9820435bda445eb471ea136d6f/debuginfo...                                                                                                    
(gdb) run
Starting program: /usr/bin/vainfo 
Downloading 519.44 K separate debug info for /usr/lib/libva.so.2
Downloading 11.17 M separate debug info for /usr/lib/libX11.so.6                                                                                                                                                   
Downloading 159.48 K separate debug info for /usr/lib/libva-x11.so.2                                                                                                                                               
Downloading 45.52 K separate debug info for /usr/lib/libva-drm.so.2                                                                                                                                                
Downloading 263.55 K separate debug info for /usr/lib/libdrm.so.2                                                                                                                                                  
Downloading 166.34 K separate debug info for /usr/lib/libwayland-client.so.0                                                                                                                                       
Downloading 85.94 K separate debug info for /usr/lib/libva-wayland.so.2                                                                                                                                            
[Thread debugging using libthread_db enabled]                                                                                                                                                                      
Using host libthread_db library "/usr/lib/libthread_db.so.1".
Downloading 505.83 K separate debug info for /usr/lib/libxcb.so.1
Downloading 576.46 K separate debug info for /usr/lib/libXext.so.6                                                                                                                                                 
Downloading 187.59 K separate debug info for /usr/lib/libXfixes.so.3                                                                                                                                               
Downloading 34.61 K separate debug info for /usr/lib/libX11-xcb.so.1                                                                                                                                               
Downloading 39.01 K separate debug info for /usr/lib/libxcb-dri3.so.0                                                                                                                                              
Downloading 129.49 K separate debug info for /usr/lib/libffi.so.8                                                                                                                                                  
Downloading 30.96 K separate debug info for /usr/lib/libXau.so.6                                                                                                                                                   
Downloading 55.56 K separate debug info for /usr/lib/libXdmcp.so.6                                                                                                                                                 
Trying display: wayland                                                                                                                                                                                            
Downloading 406.61 M separate debug info for /usr/lib/dri/iHD_drv_video.so
Downloading 2.69 M separate debug info for /usr/lib/libigdgmm.so.12                                                                                                                                                
                                                                                                                                                                                                                   
Program received signal SIGBUS, Bus error.
Downloading 12.39 K source file /usr/src/debug/glibc/glibc/string/../sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S
__memset_avx2_unaligned_erms () at ../sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S:210                                                                                                                     
210             VMOVU   %VMM(0), (%rdi)
(gdb) bt
#0  __memset_avx2_unaligned_erms () at ../sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S:210
#1  0x00007ffff5eba591 in XMHW_STATE_HEAP_INTERFACE::InitializeInterface (this=0x1000a60f0, StateHeapSettings=...)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/hw/mhw_state_heap.cpp:1083
#2  Mhw_StateHeapInterface_Create (ppStateHeapInterface=<optimized out>, StateHeapSettings=...)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/hw/mhw_state_heap.cpp:680
#3  0x00007ffff5e39af6 in mhw::render::Impl<mhw::render::xe2_hpg_next::Cmd>::AllocateHeaps (this=<optimized out>, stateHeapSettings=...)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/hw/mhw_render_impl.h:167
#4  0x00007ffff5dddaa0 in XRenderHal_Platform_Interface_Next::AllocateHeaps (this=<optimized out>, pRenderHal=<optimized out>, MhwStateHeapSettings=...)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/renderhal/renderhal_platform_interface_next.cpp:807
#5  0x00007ffff5dd5b04 in RenderHal_AllocateStateHeaps (pRenderHal=0x1000a3730, pSettings=<optimized out>)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/renderhal/renderhal.cpp:1502
#6  0x00007ffff5dcae73 in RenderHal_Initialize (pRenderHal=0x1000a3730, pSettings=<optimized out>)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/renderhal/renderhal.cpp:5381
#7  0x00007ffff5dcc8d7 in RenderCopyStateNext::Initialize (this=0x1000a31d0)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/shared/mediacopy/media_render_copy_next.cpp:121
#8  0x00007ffff5e7a25b in McpyDeviceNext_T<MhwInterfacesNext, MediaCopyStateXe2_Hpm_Base>::Initialize (this=0x10009c070, osInterface=<optimized out>)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/media_interfaces/media_interfaces_mcpy_next.h:127
#9  0x00007ffff5dfbbbb in McpyDeviceNext::CreateFactory (osDriverContext=<optimized out>)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/linux/common/media_interfaces/media_interfaces_next.cpp:414
#10 0x00007ffff54c71ec in MosMediaCopyBase::MosMediaCopyBase (this=0x10009a470, mosCtx=0x7fffffff65c0)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/linux/common/os/mos_mediacopy_base.cpp:34
#11 MosMediaCopyBase::MosMediaCopyBase (this=0x10009a470, mosCtx=0x7fffffff65c0) at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/linux/common/os/mos_mediacopy_base.cpp:31
#12 MosMediaCopy::MosMediaCopy (this=0x10009a470, mosCtx=0x7fffffff65c0) at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_driver/linux/common/os/mos_mediacopy.cpp:32
#13 MosUtilities::MosNewUtil<MosMediaCopy, _MOS_OS_CONTEXT*&> () at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/os/mos_utilities.h:3008
#14 OsContextSpecificNext::Init (this=0x10005afc0, ddiDriverContext=0x7fffffff65c0)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/linux/common/os/mos_context_specific_next.cpp:329
#15 0x00007ffff566f5cf in MosInterface::CreateOsDeviceContext (ddiDeviceContext=0x7fffffff65c0, deviceContext=0x100050d40)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/linux/common/os/mos_interface.cpp:128
#16 DdiMedia_InitMediaContext(VADriverContext*, int, int*, int*, bool&) [clone .constprop.0] (ctx=<optimized out>, devicefd=<optimized out>, apoDdiEnabled=<optimized out>, minor_version=<optimized out>, 
    major_version=<optimized out>) at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_driver/linux/common/ddi/media_libva.cpp:1786
#17 0x00007ffff567705e in DdiMedia__Initialize (major_version=0x0, minor_version=0x0, ctx=0x10000f8e0)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_driver/linux/common/ddi/media_libva.cpp:1691
#18 __vaDriverInit (ctx=0x10000f8e0) at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_driver/linux/common/ddi/media_libva.cpp:7503
#19 __vaDriverInit_1_22 (ctx=0x10000f8e0) at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_driver/linux/common/ddi/media_libva.cpp:7529
#20 0x00007ffff7f592e7 in va_openDriver (dpy=0x10000f5a0, driver_name=<optimized out>) at ../libva/va/va.c:478
#21 va_new_opendriver (dpy=0x10000f5a0) at ../libva/va/va.c:714
#22 vaInitialize (dpy=0x10000f5a0, major_version=0x7fffffffd954, minor_version=0x7fffffffd950) at ../libva/va/va.c:743
#23 vaInitialize (dpy=dpy@entry=0x10000f5a0, major_version=major_version@entry=0x7fffffffd954, minor_version=minor_version@entry=0x7fffffffd950) at ../libva/va/va.c:727
#24 0x00000001000022b0 in main (argc=<optimized out>, argv=<optimized out>) at ../libva-utils-2.22.0/vainfo/vainfo.c:532
(gdb) info registers
rax            0x7ffff7fb9000      140737353846784
rbx            0x1000a60f0         4295647472
rcx            0x7ffff7b16c8c      140737348988044
rdx            0x40                64
rsi            0x0                 0
rdi            0x7ffff7fb9000      140737353846784
rbp            0x7fffffff50b0      0x7fffffff50b0
rsp            0x7fffffff4fd8      0x7fffffff4fd8
r8             0x4                 4
r9             0x10b512000         4484833280
r10            0x1000b0aa0         4295690912
r11            0x246               582
r12            0x80                128
r13            0x0                 0
r14            0x1b0080            1769600
r15            0xf40               3904
rip            0x7ffff7b6e7a0      0x7ffff7b6e7a0 <__memset_avx2_unaligned_erms+32>
eflags         0x10246             [ PF ZF IF RF ]
cs             0x33                51
ss             0x2b                43
ds             0x0                 0
es             0x0                 0
fs             0x0                 0
gs             0x0                 0
fs_base        0x7ffff7d36740      140737351214912
gs_base        0x0                 0
(gdb) info locals
No locals.
(gdb) up 1
iDownloading 70.87 K source file /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/hw/mhw_state_heap.cpp
#1  0x00007ffff5eba591 in XMHW_STATE_HEAP_INTERFACE::InitializeInterface (this=0x1000a60f0, StateHeapSettings=...)                                                                                                 
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/hw/mhw_state_heap.cpp:1083
1083        MOS_ZeroMemory(m_pdwCmdBufIdGlobal, AllocParams.dwBytes);
(gdb) info locals
AllocParams = {Type = MOS_GFXRES_BUFFER, Flags = {bNotLockable = 0, bOverlay = 0, bFlipChain = 0, bSVM = 0, bCacheable = 0}, {dwWidth = 64, dwBytes = 64}, dwHeight = 0, dwDepth = 0, dwArraySize = 0, 
  TileType = MOS_TILE_LINEAR, m_tileModeByForce = MOS_TILE_LINEAR_GMM, Format = Format_Buffer, pSystemMemory = 0x0, pBufName = 0x7ffff5ec391c "CmdBufIdGlobal", bIsCompressible = 0, 
  CompressionMode = MOS_MMC_DISABLED, bIsPersistent = 0, bBypassMODImpl = 0, dwMemType = 0, ResUsageType = MOS_CODEC_RESOURCE_USAGE_BEGIN_CODEC, hardwareProtected = false}
LockParams = {{{ReadOnly = 0, WriteOnly = 1, TiledAsTiled = 0, NoOverWrite = 0, NoDecompress = 0, Uncached = 0, ForceCached = 0, DumpBeforeSubmit = 0, DumpAfterSubmit = 0, Reserved = 0}, Value = 2}}
eStatus = MOS_STATUS_SUCCESS
(gdb) p AllocParams.dwBytes
$1 = 64
(gdb) p m_pdwCmdBufIdGlobal
$2 = (uint32_t *) 0x7ffff7fb9000
(gdb) p *m_pdwCmdBufIdGlobal
Cannot access memory at address 0x7ffff7fb9000
(gdb) l
1078        m_pdwCmdBufIdGlobal = (uint32_t*)m_pOsInterface->pfnLockResource(
1079            m_pOsInterface,
1080            &m_resCmdBufIdGlobal,
1081            &LockParams);
1082        MHW_CHK_NULL_RETURN(m_pdwCmdBufIdGlobal);
1083        MOS_ZeroMemory(m_pdwCmdBufIdGlobal, AllocParams.dwBytes);
1084        m_dwCurrCmdBufId = 1;
1085
1086        //Extend state heap for ISH
1087        MHW_CHK_STATUS_RETURN(ExtendStateHeap(
(gdb) bt
#0  __memset_avx2_unaligned_erms () at ../sysdeps/x86_64/multiarch/memset-vec-unaligned-erms.S:210
#1  0x00007ffff5eba591 in XMHW_STATE_HEAP_INTERFACE::InitializeInterface (this=0x1000a60f0, StateHeapSettings=...)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/hw/mhw_state_heap.cpp:1083
#2  Mhw_StateHeapInterface_Create (ppStateHeapInterface=<optimized out>, StateHeapSettings=...)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/hw/mhw_state_heap.cpp:680
#3  0x00007ffff5e39af6 in mhw::render::Impl<mhw::render::xe2_hpg_next::Cmd>::AllocateHeaps (this=<optimized out>, stateHeapSettings=...)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/hw/mhw_render_impl.h:167
#4  0x00007ffff5dddaa0 in XRenderHal_Platform_Interface_Next::AllocateHeaps (this=<optimized out>, pRenderHal=<optimized out>, MhwStateHeapSettings=...)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/renderhal/renderhal_platform_interface_next.cpp:807
#5  0x00007ffff5dd5b04 in RenderHal_AllocateStateHeaps (pRenderHal=0x1000a3730, pSettings=<optimized out>)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/renderhal/renderhal.cpp:1502
#6  0x00007ffff5dcae73 in RenderHal_Initialize (pRenderHal=0x1000a3730, pSettings=<optimized out>)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/renderhal/renderhal.cpp:5381
#7  0x00007ffff5dcc8d7 in RenderCopyStateNext::Initialize (this=0x1000a31d0)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/shared/mediacopy/media_render_copy_next.cpp:121
#8  0x00007ffff5e7a25b in McpyDeviceNext_T<MhwInterfacesNext, MediaCopyStateXe2_Hpm_Base>::Initialize (this=0x10009c070, osInterface=<optimized out>)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/media_interfaces/media_interfaces_mcpy_next.h:127
#9  0x00007ffff5dfbbbb in McpyDeviceNext::CreateFactory (osDriverContext=<optimized out>)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/linux/common/media_interfaces/media_interfaces_next.cpp:414
#10 0x00007ffff54c71ec in MosMediaCopyBase::MosMediaCopyBase (this=0x10009a470, mosCtx=0x7fffffff65c0)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/linux/common/os/mos_mediacopy_base.cpp:34
#11 MosMediaCopyBase::MosMediaCopyBase (this=0x10009a470, mosCtx=0x7fffffff65c0) at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/linux/common/os/mos_mediacopy_base.cpp:31
#12 MosMediaCopy::MosMediaCopy (this=0x10009a470, mosCtx=0x7fffffff65c0) at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_driver/linux/common/os/mos_mediacopy.cpp:32
#13 MosUtilities::MosNewUtil<MosMediaCopy, _MOS_OS_CONTEXT*&> () at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/agnostic/common/os/mos_utilities.h:3008
#14 OsContextSpecificNext::Init (this=0x10005afc0, ddiDriverContext=0x7fffffff65c0)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/linux/common/os/mos_context_specific_next.cpp:329
#15 0x00007ffff566f5cf in MosInterface::CreateOsDeviceContext (ddiDeviceContext=0x7fffffff65c0, deviceContext=0x100050d40)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_softlet/linux/common/os/mos_interface.cpp:128
#16 DdiMedia_InitMediaContext(VADriverContext*, int, int*, int*, bool&) [clone .constprop.0] (ctx=<optimized out>, devicefd=<optimized out>, apoDdiEnabled=<optimized out>, minor_version=<optimized out>, 
    major_version=<optimized out>) at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_driver/linux/common/ddi/media_libva.cpp:1786
#17 0x00007ffff567705e in DdiMedia__Initialize (major_version=0x0, minor_version=0x0, ctx=0x10000f8e0)
    at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_driver/linux/common/ddi/media_libva.cpp:1691
#18 __vaDriverInit (ctx=0x10000f8e0) at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_driver/linux/common/ddi/media_libva.cpp:7503
#19 __vaDriverInit_1_22 (ctx=0x10000f8e0) at /usr/src/debug/intel-media-driver/media-driver-intel-media-25.3.4/media_driver/linux/common/ddi/media_libva.cpp:7529
#20 0x00007ffff7f592e7 in va_openDriver (dpy=0x10000f5a0, driver_name=<optimized out>) at ../libva/va/va.c:478
#21 va_new_opendriver (dpy=0x10000f5a0) at ../libva/va/va.c:714
#22 vaInitialize (dpy=0x10000f5a0, major_version=0x7fffffffd954, minor_version=0x7fffffffd950) at ../libva/va/va.c:743
#23 vaInitialize (dpy=dpy@entry=0x10000f5a0, major_version=major_version@entry=0x7fffffffd954, minor_version=minor_version@entry=0x7fffffffd950) at ../libva/va/va.c:727
#24 0x00000001000022b0 in main (argc=<optimized out>, argv=<optimized out>) at ../libva-utils-2.22.0/vainfo/vainfo.c:532
(gdb) 

It appears the value returned by pfnLockResource isn't valid memory?

[Reabstraction]

Enabling ReBAR fixes it

Still; it shouldn't crash under these conditions
But gracefully degrade to "no encoding/decoding available"

[TheDon79]

I’ve encountered the same issue on my system. Since my hardware is older and doesn’t support ReBAR, I’d really appreciate any help or workarounds for this problem.

---

Environment

Mainboard: Asus H170-Pro
CPU: Intel Core i5-6600
GPU: Intel Arc B580 with 12GB
RAM: 32GB DDR4

Running CachyOS with Linux 6.18.5-2.

❯ sudo inxi -Fmxxz
System:
  Kernel: 6.18.5-2-cachyos arch: x86_64 bits: 64 compiler: clang v: 21.1.6
  Desktop: KDE Plasma v: 6.5.4 tk: Qt v: N/A wm: kwin_wayland dm: SDDM
    Distro: CachyOS base: Arch Linux
Machine:
  Type: Desktop Mobo: ASUSTeK model: H170-PRO v: Rev X.0x serial: <filter>
    part-nu: SKU Firmware: UEFI vendor: American Megatrends v: 3805
    date: 05/16/2018
Memory:
  System RAM: total: 32 GiB available: 31.27 GiB used: 3.13 GiB (10.0%)
  Array-1: capacity: 64 GiB slots: 4 modules: 2 EC: None
    max-module-size: 16 GiB note: est.
  Device-1: DIMM_A1 type: DDR4 size: 16 GiB speed: 2133 MT/s volts: 1.2
    manufacturer: Kingston part-no: 9905625-066.A00G
  Device-2: DIMM_A2 type: no module installed
  Device-3: DIMM_B1 type: DDR4 size: 16 GiB speed: 2133 MT/s volts: 1.2
    manufacturer: Kingston part-no: 9905625-066.A00G
  Device-4: DIMM_B2 type: no module installed
CPU:
  Info: quad core model: Intel Core i5-6600 bits: 64 type: MCP arch: Skylake-S
    rev: 3 cache: L1: 256 KiB L2: 1024 KiB L3: 6 MiB
  Speed (MHz): avg: 800 min/max: 800/3900 cores: 1: 800 2: 800 3: 800 4: 800
    bogomips: 26399
  Flags-basic: avx avx2 ht lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3
Graphics:
  Device-1: Intel Battlemage G21 [Arc B580] vendor: ASRock driver: xe
    v: kernel arch: Xe2 pcie: speed: 2.5 GT/s lanes: 1 ports: active: DP-1,DP-4
    empty: DP-2, DP-3, DP-5, HDMI-A-1, HDMI-A-2, HDMI-A-3, HDMI-A-4
    bus-ID: 03:00.0 chip-ID: 8086:e20b
  Device-2: SHENZHEN EMEET HD Webcam C960
    driver: hid-generic,snd-usb-audio,usbhid,uvcvideo type: USB rev: 2.0
    speed: 480 Mb/s lanes: 1 bus-ID: 1-8.3:4 chip-ID: 328f:2013
  Display: unspecified server: X.Org v: 24.1.9 with: Xwayland v: 24.1.9
    compositor: kwin_wayland driver: gpu: xe display-ID: :0 screens: 1
  Screen-1: 0 s-res: 7104x2560 s-dpi: 96
  Monitor-1: DP-1 pos: primary,left model: BenQ RD280U res: 3840x2560 hz: 60
    dpi: 163 diag: 717mm (28.2")
  Monitor-2: DP-4 pos: right model: Dell U2415 res: 3264x2040 hz: 60
    dpi: 160 diag: 611mm (24.1")
  API: EGL v: 1.5 platforms: device: 0 drv: iris device: 1 drv: swrast gbm:
    drv: iris surfaceless: drv: iris x11: drv: iris inactive: wayland
  API: OpenGL v: 4.6 compat-v: 4.5 vendor: intel mesa v: 25.3.3-arch1.5
    glx-v: 1.4 direct-render: yes renderer: Mesa Intel Arc B580 Graphics (BMG
    G21) device-ID: 8086:e20b
  API: Vulkan v: 1.4.335 surfaces: N/A device: 0 type: discrete-gpu
    driver: mesa intel device-ID: 8086:e20b
  Info: Tools: api: clinfo, eglinfo, glxinfo, vulkaninfo
    de: kscreen-console,kscreen-doctor wl: wayland-info
    x11: xdpyinfo, xprop, xrandr

---

Stacktrace with gdb

Here is the output of gdb running vainfo

Program received signal SIGBUS, Bus error.
0x00007ffff7b98ee0 in ?? () from /usr/lib/libc.so.6
(gdb) bt
#0  0x00007ffff7b98ee0 in ?? () from /usr/lib/libc.so.6
#1  0x00007ffff5e85541 in ?? () from /usr/lib/dri/iHD_drv_video.so
#2  0x00007ffff5e078a6 in ?? () from /usr/lib/dri/iHD_drv_video.so
#3  0x00007ffff5dad8b0 in ?? () from /usr/lib/dri/iHD_drv_video.so
#4  0x00007ffff5da5b21 in ?? () from /usr/lib/dri/iHD_drv_video.so
#5  0x00007ffff5d9af73 in ?? () from /usr/lib/dri/iHD_drv_video.so
#6  0x00007ffff5d9c906 in ?? () from /usr/lib/dri/iHD_drv_video.so
#7  0x00007ffff5e46a2a in ?? () from /usr/lib/dri/iHD_drv_video.so
#8  0x00007ffff5dcb09b in ?? () from /usr/lib/dri/iHD_drv_video.so
#9  0x00007ffff54c434a in ?? () from /usr/lib/dri/iHD_drv_video.so
#10 0x00007ffff5662f38 in ?? () from /usr/lib/dri/iHD_drv_video.so
#11 0x00007ffff566a68e in __vaDriverInit_1_22 () from /usr/lib/dri/iHD_drv_video.so
#12 0x00007ffff7f5afdb in va_openDriver () at ../libva/va/va.c:478
#13 va_new_opendriver () at ../libva/va/va.c:714
#14 vaInitialize () at ../libva/va/va.c:743
#15 vaInitialize () at ../libva/va/va.c:727
#16 0x0000555555556288 in main () at ../libva-utils-2.22.0/vainfo/vainfo.c:532

[nyanmisaka]

Hi @XinfengZhang, could you please clarify whether both Battlemage and future dGPUs using Xe KMD will no longer be compatible with motherboards that do not support resizable BAR?

We have encountered many similar cases on Arc B580/B570 and Pro B50, and if this is indeed the case, I would advise them to replace their motherboard or find an alternative. It would be even better if this limitation were mentioned in the README.

[butchermustdie]

Hi!
The issue was resolved only by enabling ReBAR. To do this, I had to reflash the motherboard BIOS.

https://github.com/Koshak1013/HuananzhiX99_BIOS_mods?tab=readme-ov-file#%D0%B4%D0%BE%D0%B1%D0%B0%D0%B2%D0%BB%D0%B5%D0%BD%D0%B8%D0%B5-%D0%BF%D0%BE%D0%B4%D0%B4%D0%B5%D1%80%D0%B6%D0%BA%D0%B8-resizable-bar-%D0%B2-%D0%B1%D0%B8%D0%BE%D1%81
https://forums.overclockers.ru/viewtopic.php?f=1&t=602922&start=42740

[philipborg]

Has anyone tried this as a solution? #1990

[caniko]

Additional data point: I hit the same SIGBUS class on Arc A770 / DG2 (device 0x56a0) with the xe kernel driver and Small BAR / ReBAR unavailable.

This presented as repeated Chromium GPU-process crashes, Floorp vaapitest SIGBUS, and earlier Steam CEF/steamwebhelper SIGBUS. In one case the repeated browser GPU-process crashes were followed by a COSMIC compositor/session crash, but the actionable first failure is in iHD_drv_video.so -> vaInitialize.

System

• Distro: NixOS 26.05.20260422.0726a0e
• Kernel: 7.0.1-cachyos-lto
• GPU: Intel Arc A770 / DG2, PCI 8086:56a0
• Kernel driver: xe
• Kernel cmdline includes: i915.force_probe=!56a0 xe.force_probe=56a0
• media-driver: intel-media-driver-26.1.2
• Mesa: 26.0.5
• libva: reports VA-API version 1.23.0
• VA driver: LIBVA_DRIVER_NAME=iHD
• iHD_drv_video.so: /nix/store/...-intel-media-driver-26.1.2/lib/dri/iHD_drv_video.so

ReBAR / BAR status

Kernel log:

xe 0000:0b:00.0: [drm] Attempting to resize bar from 256MiB -> 16384MiB
xe 0000:0b:00.0: [drm] Can't resize VRAM BAR - platform support is missing. Consider enabling 'Resizable BAR' support in your BIOS
xe 0000:0b:00.0: [drm] VISIBLE VRAM: 0x00000000e0000000, 0x0000000010000000
xe 0000:0b:00.0: [drm] Small BAR device
xe 0000:0b:00.0: [drm] VRAM[0]: Actual physical size 0x0000000400000000, usable size exclude stolen 0x00000003fa000000, CPU accessible size 0x0000000010000000
xe 0000:0b:00.0: [drm] VRAM: 0x0000000400000000 is larger than resource 0x0000000010000000

Coredump timeline

Wed 2026-04-29 14:47:25 CEST 106038 SIGBUS  chromium --type=gpu-process
Wed 2026-04-29 14:47:29 CEST 106365 SIGBUS  chromium --type=gpu-process
Wed 2026-04-29 14:47:33 CEST 106530 SIGBUS  chromium --type=gpu-process
Wed 2026-04-29 14:47:36 CEST 106684 SIGBUS  chromium --type=gpu-process
Wed 2026-04-29 14:47:40 CEST 106953 SIGBUS  chromium --type=gpu-process
Wed 2026-04-29 14:47:43 CEST 106978 SIGBUS  chromium --type=gpu-process
Wed 2026-04-29 14:48:00 CEST 107133 SIGBUS  floorp-bin .../vaapitest
Wed 2026-04-29 14:48:11 CEST 105986 SIGTRAP chromium

The crashing Chromium GPU process was launched with VA-API enabled:

chromium --type=gpu-process --ozone-platform=wayland --render-node-override=/dev/dri/renderD128 --use-gl=angle --enable-features=AcceleratedVideoDecodeLinuxZeroCopyGL,AcceleratedVideoEncoder,VaapiIgnoreDriverChecks,VaapiVideoDecodeLinuxGL,VaapiVideoDecoder,VaapiVideoEncoder

Representative backtrace

#0  __memset_avx2_unaligned_erms (libc.so.6 + 0x180fe0)
#1  XMHW_STATE_HEAP_INTERFACE::InitializeInterface(MHW_STATE_HEAP_SETTINGS) (iHD_drv_video.so + 0xdb7d56)
#2  Mhw_StateHeapInterface_Create(_MHW_STATE_HEAP_INTERFACE**, MHW_STATE_HEAP_SETTINGS) (iHD_drv_video.so + 0xdb81a2)
#3  MhwRenderInterface::AllocateHeaps(MHW_STATE_HEAP_SETTINGS) (iHD_drv_video.so + 0x2d577d)
#4  XRenderHal_Platform_Interface_Legacy::AllocateHeaps(RENDERHAL_INTERFACE*, MHW_STATE_HEAP_SETTINGS) (iHD_drv_video.so + 0x2db6de)
#5  RenderHal_AllocateStateHeaps(RENDERHAL_INTERFACE*, RENDERHAL_STATE_HEAP_SETTINGS*) (iHD_drv_video.so + 0xc508be)
#6  RenderHal_Initialize(RENDERHAL_INTERFACE*, RENDERHAL_SETTINGS*) (iHD_drv_video.so + 0xc4eedb)
#7  RenderCopyState::Initialize() (iHD_drv_video.so + 0x2dd15d)
#8  McpyDeviceXe_Hpm::Initialize(MOS_INTERFACE*) (iHD_drv_video.so + 0x41640d)
#9  McpyDevice::CreateFactory(MOS_OS_CONTEXT*) (iHD_drv_video.so + 0x4abdab)
#10 MosMediaCopy::MosMediaCopy(MOS_OS_CONTEXT*) (iHD_drv_video.so + 0x226d20)
#11 OsContextSpecificNext::Init(void*) (iHD_drv_video.so + 0x2609ce)
#12 DdiMedia_InitMediaContext(VADriverContext*, int, int*, int*, bool) (iHD_drv_video.so + 0x455e2c)
#13 __vaDriverInit_1_23 (iHD_drv_video.so + 0x456c3d)
#14 vaInitialize (libva.so.2 + 0x4443)
#15 media::VADisplayStateSingleton::GetHandle() (chromium + 0x6ed859b)
#16 media::VaapiWrapper::PreSandboxInitialization(bool) (chromium + 0x6ee2035)
#17 content::ContentSandboxHelper::PreSandboxStartup(gpu::GpuPreferences const&) (chromium + 0xd2cf775)
#18 gpu::GpuInit::InitializeAndStartSandbox(base::CommandLine*, gpu::GpuPreferences const&) (chromium + 0xca3e59a)
#19 content::GpuMain(content::MainFunctionParams) (chromium + 0xd2cef36)

Workaround is the same as discussed above: prevent clients from using iHD VA-API on this host, e.g. LIBVA_DRIVER_NAME=dummy for Steam CEF, and disabling VA-API browser acceleration. That avoids the SIGBUS path, but it would be better if media-driver failed gracefully when the required BAR mapping is unavailable instead of crashing clients.