Virtual display doesn't allocate amdgpu_encoder when initializing,
so will get invaild pointer if try to free amdgpu_encoder when
unloading driver.
Signed-off-by: Xiangliang Yu <Xiangliang.Yu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Return success when the ring is properly initialized, otherwise return
failure.
Tonga SRIOV VF doesn't have UVD and VCE engines, the initialization of
these IPs is bypassed. The system crashes if application submit IB to
their rings which are not ready to use. It could be a common issue if
IP having ring buffer is disabled for some reason on specific ASIC, so
it should check the ring being ready to use.
Bug: amdgpu_test crashes system on Tonga VF.
Signed-off-by: Ding Pixel <Pixel.Ding@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
a single fix for a FE hang after IOVA rollover on GC3000. This isn't
pretty, but is the minimal fix for the issue. A larger rework of the
code, that will also fix this issue properly, is currently in the works,
but that needs to wait for at least the next feature pull.
* 'drm-etnaviv-fixes' of https://git.pengutronix.de/git/lst/linux:
drm/etnaviv: trick drm_mm into giving out a low IOVA
Just regression fixups to resolve page fault issue of DECON device.
* 'exynos-drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/daeinki/drm-exynos:
drm/exynos/decon5433: set STANDALONE_UPDATE_F on output enablement
drm/exynos/decon5433: fix CMU programming
drm/exynos/decon5433: do not disable video after reset
drm/exynos/decon5433: set STANDALONE_UPDATE_F also if planes are disabled
drm/exynos/decon5433: update shadow registers iff there are active windows
A little bigger than usual since it's two weeks worth. Highlights:
- Add support for new smc firmware on some new hainan variants
- add support for SI chips that require special mc firmware
- remove workarounds for issues fixed by new mc firmware
- fix a regression in cursor handling
- various VCE fixes
- fix for UVD clockgating
* 'drm-fixes-4.10' of git://people.freedesktop.org/~agd5f/linux:
drm/amdgpu: add support for new hainan variants
drm/radeon: add support for new hainan variants
drm/amdgpu: change clock gating mode for uvd_v4.
drm/amdgpu: fix program vce instance logic error.
drm/amdgpu: fix bug set incorrect value to vce register
Revert "drm/amdgpu: Only update the CUR_SIZE register when necessary"
drm/amd/powerplay: refine vce dpm update code on Cz.
drm/amdgpu: fix vm_fault_stop on gfx6
drm/amd/powerplay: fix vce cg logic error on CZ/St.
drm/radeon: drop the mclk quirk for hainan
drm/radeon: drop oland quirks
drm/amdgpu: drop the mclk quirk for hainan
drm/amdgpu: drop oland quirks
drm/amdgpu/si: load special ucode for certain MC configs
drm/radeon/si: load special ucode for certain MC configs
* 'msm-fixes-4.10-rc4' of git://people.freedesktop.org/~robclark/linux:
drm/msm: fix potential null ptr issue in non-iommu case
drm/msm/mdp5: rip out plane->pending tracking
A few more core fixes.
* tag 'drm-misc-fixes-2017-01-13' of git://anongit.freedesktop.org/git/drm-misc:
drm/probe-helpers: Drop locking from poll_enable
drm: Fix broken VT switch with video=1366x768 option
drm: Schedule the output_poll_work with 1s delay if we have delayed event
More GVT-g stuff than I'd like at this stage, but then again that's
pretty new and isolated so I'm not too worried.
* tag 'drm-intel-fixes-2017-01-19' of git://anongit.freedesktop.org/git/drm-intel: (26 commits)
drm/i915: Ignore bogus plane coordinates on SKL when the plane is not visible
drm/i915: Remove WaDisableLSQCROPERFforOCL KBL workaround.
drm/i915/gvt: rewrite gt reset handler using new function intel_gvt_reset_vgpu_locked
drm/i915/gvt: fix vGPU instance reuse issues by vGPU reset function
drm/i915/gvt: introduce intel_vgpu_reset_mmio() to reset mmio space
drm/i915/gvt: move mmio init/clean function to mmio.c
drm/i915/gvt: introduce intel_vgpu_reset_cfg_space to reset configuration space
drm/i915/gvt: move cfg space inititation function to cfg_space.c
drm/i915/gvt: introuduce intel_vgpu_reset_gtt() to reset gtt
drm/i915/gvt: introudce intel_vgpu_reset_resource() to reset vgpu resource state
drm/i915: Fix phys pwrite for struct_mutex-less operation
drm/i915: Clear ret before unbinding in i915_gem_evict_something()
drm/i915/gvt: cleanup GFP flags
drm/i915/gvt/kvmgt: return meaningful error for vgpu creating failure
drm/i915/gvt: cleanup opregion memory allocation code
drm/i915/gvt: destroy the allocated idr on vgpu creating failures
drm/i915/gvt: init/destroy vgpu_idr properly
drm/i915/gvt: dec vgpu->running_workload_num after the workload is really done
drm/i915/gvt: fix use after free for workload
drm/i915/gvt: remove duplicated definition
...
DECON_TV requires STANDALONE_UPDATE after output enabling, otherwise it does
not start. This change is neutral for DECON.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
DECON_CMU register has reserved bits which should not be zeroed, otherwise
IP can behave strangely and cause IOMMU faults.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
decon_commit is called just after reset so video is disabled anyway.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
When the plane is invisible we may have all sorts of bogus stuff
in the coordinates, which we must ignore or else we might fail the
plane update. This started to happen on SKL when I moved the plane
offset computation to happen in the check phase. Previously we
happily ignored it all since we never called the update_plane hook
with an invisible plane.
Cc: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com>
Cc: drm-intel-fixes@lists.freedesktop.org
Fixes: b63a16f6cd ("drm/i915: Compute display surface offset in the plane check hook for SKL+")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98258
Testcase: igt/pm_rpm/legacy-planes
Testcase: igt/pm_rpm/universal-planes
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1478550057-24864-3-git-send-email-ville.syrjala@linux.intel.com
(cherry picked from commit a5e4c7d0aa)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
The WaDisableLSQCROPERFforOCL workaround has the side effect of
disabling an L3SQ optimization that has huge performance implications
and is unlikely to be necessary for the correct functioning of usual
graphic workloads. Userspace is free to re-enable the workaround on
demand, and is generally in a better position to determine whether the
workaround is necessary than the DRM is (e.g. only during the
execution of compute kernels that rely on both L3 fences and HDC R/W
requests).
The same workaround seems to apply to BDW (at least to production
stepping G1) and SKL as well (the internal workaround database claims
that it does for all steppings, while the BSpec workaround table only
mentions pre-production steppings), but the DRM doesn't do anything
beyond whitelisting the L3SQCREG4 register so userspace can enable it
when it sees fit. Do the same on KBL platforms.
Improves performance of the GFXBench4 gl_manhattan31 benchmark by 60%,
and gl_4 (AKA car chase) by 14% on a KBL GT2 running Mesa master --
This is followed by a regression of 35% and 10% respectively for the
same benchmarks and platform caused by my recent patch series
switching userspace to use the dataport constant cache instead of the
sampler to implement uniform pull constant loads, which caused us to
hit more heavily the L3 cache (and on platforms other than KBL had the
opposite effect of improving performance of the same two benchmarks).
The overall effect on KBL of this change combined with the recent
userspace change is respectively 4.6% and 2.6%. SynMark2 OglShMapPcf
was affected by the constant cache changes (though it improved as it
did on other platforms rather than regressing), but is not
significantly affected by this patch (with statistical significance of
5% and sample size 20).
v2: Drop some more code to avoid unused variable warning.
Fixes: 738fa1b312 ("drm/i915/kbl: Add WaDisableLSQCROPERFforOCL")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99256
Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Cc: Eero Tamminen <eero.t.tamminen@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: beignet@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v4.7+
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
[Removed double Fixes tag]
Signed-off-by: Mika Kuoppala <mika.kuoppala@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1484217894-20505-1-git-send-email-mika.kuoppala@intel.com
(cherry picked from commit 8726f2faa3)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
need to clear bit31-29 in GRBM_GFX_INDEX,
then the program can be valid.
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Set the proper bits for clockgating setup.
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This reverts commits 7c83d7abc9 and
a1f49cc179.
They caused the HW cursor to disappear under various circumstances in
the wild. I wasn't able to reproduce any of them, and I'm not sure
what's going on. But those changes aren't a big deal anyway, so let's
just revert for now.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=191291
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99143
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Fixes: 9cb07b099fb ("drm/msm: support multiple address spaces")
Reported-by: Riku Voipio <riku.voipio@linaro.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
It would race between userspace thread and commit worker. Ie. vblank
irq would trigger event and userspace could begin the next atomic
update, before the commit worker had a chance to clear the pending
flag.
If we do end up needing something to prevent userspace from trying
another pageflip before getting vblank event, it should probably be
implemented as a pending_planes bitmask, similar to pending_crtcs. See
start_atomic() and end_atomic().
Signed-off-by: Rob Clark <robdclark@gmail.com>
STANDALONE_UPDATE_F should be set if something changed in plane configurations,
including plane disable.
The patch fixes page-faults bugs, caused by decon still using framebuffers
of disabled planes.
v2: fixed clear-bit code (Thx Marek)
v3: use test_and_clear_bit (Thx Joonyoung)
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Tested-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Improper usage of DECON_UPDATE register leads to subtle errors.
If it set in decon_commit when there are no active windows it results
in slow registry updates - all subsequent shadow registry updates takes more
than full vblank. On the other side if it is not set when there are
active windows it results in garbage on the screen after suspend/resume of
FB console.
The patch hopefully fixes it.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
GT reset and FLR share some operations and they are both implemented in
our new function intel_gvt_reset_vgpu_locked(). This patch rewrite the
gt reset handler using this new function.
Besides, this new implementation fixed the old issue in GT reset. The
old implementation reset GGTT entries which is illegal. We only clear
GGTT entries at PCI level reset.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Our function tests found several issues related to reusing vGPU
instance. They are qemu reboot failure, guest tdr after reboot, host
hang when reboot guest. All these issues are caused by dirty status
inherited from last VM.
This patch fix all these issues by resetting a virtual GPU before VM
use it. The reset logical is put into a low level function
_intel_gvt_reset_vgpu(), which supports Device Model Level Reset, Full
GT Reset and Per-Engine Reset.
vGPU Device Model Level Reset (DMLR) simulates the PCI reset to reset
the whole vGPU to default state as when it is created, including GTT,
execlist, scratch pages, cfg space, mmio space, pvinfo page, scheduler
and fence registers. The ultimate goal of vGPU DMLR is that reuse a
vGPU instance by different virtual machines. When we reassign a vGPU
to a virtual machine we must issue such reset first.
Full GT Reset and Per-Engine GT Reset are soft reset flow for GPU engines
(Render, Blitter, Video, Video Enhancement). It is defined by GPU Spec.
Unlike the FLR, GT reset only reset particular resource of a vGPU per
the reset request. Guest driver can issue a GT reset by programming
the virtual GDRST register to reset specific virtual GPU engine or all
engines.
Since vGPU DMLR and GT reset can share some code so we implement both
these two into one single function intel_gvt_reset_vgpu_locked(). The
parameter dmlr is to identify if we will do FLR or GT reset. The
parameter engine_mask is to specific the engines that need to be
resetted. If value ALL_ENGINES is given for engine_mask, it means
the caller requests a full gt reset that we will reset all virtual
GPU engines.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Reviewed-by: Jike Song <jike.song@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces a new function intel_vgpu_reset_mmio() to
reset vGPU MMIO space (virtual registers of the vGPU). The default
values are loaded as firmware during gvt inititiation.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Move the mmio space inititation function setup_vgpu_mmio()
and cleanup function clean_vgpu_mmio() in vgpu.c to dedicated
source file mmio.c, and rename them as intel_vgpu_init_mmio()
and intel_vgpu_clean_mmio() respectively.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces a new function intel_vgpu_reset_cfg_space()
to reset vGPU configuration space. This function will unmap gttmmio
and aperture if they are mapped before. Then entire cfg space will
be restored to default values.
Currently we only do such reset when vGPU is not owned by any VM
so we simply restore entire cfg space to default value, not following
the PCIe FLR spec that some fields should remain unchanged.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Move the configuration space inititation function setup_vgpu_cfg_space()
in vgpu.c to dedicated source file cfg_space.c, and rename the function
as intel_vgpu_init_cfg_space().
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces a new function intel_vgpu_reset_gtt() to reset
the all GTT related status, including GGTT, PPGTT, scratch page. This
function can free all shadowed PPGTT, clear all GGTT entry, and clear
scratch page to all zero. After this, we can ensure no gtt related
information can be leakaged from one VM to anothor one when assign
vgpu instance across different VMs (not simultaneously).
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introudces a new function intel_vgpu_reset_resource() to
reset allocated vgpu resources by intel_vgpu_alloc_resource(). So far
we only need clear the fence registers. The function _clear_vgpu_fence()
will reset both virtual and physical fence registers to 0.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Program HardMin based on the vce_arbiter.ecclk
if ecclk is 0, disable ECLK DPM 0. Otherwise VCE
could hang if switching SCLK from DPM 0 to 6/7
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Flora Cui <Flora.Cui@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
can fix Bug 191281: vce ib test failed.
when vce idle, set vce clock gate, so the clock
in vce domain will be disabled.
when need to encode, disable vce clock gate,
enable the clocks to vce engine.
Signed-off-by: Rex Zhu <Rex.Zhu@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Special MC ucode is required for these memory configurations.
Acked-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Special MC ucode is required for these memory configurations.
Acked-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
It was only needed to protect the connector_list walking, see
commit 8c4ccc4ab6
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Thu Jul 9 23:44:26 2015 +0200
drm/probe-helper: Grab mode_config.mutex in poll_init/enable
Unfortunately the commit message of that patch fails to mention that
the new locking check was for the connector_list.
But that requirement disappeared in
commit c36a3254f7
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Thu Dec 15 16:58:43 2016 +0100
drm: Convert all helpers to drm_connector_list_iter
and so we can drop this again.
This fixes a locking inversion on nouveau, where the rpm code needs to
re-enable. But in other places the rpm_get() calls are nested within
the big modeset locks.
While at it, also improve the kerneldoc for these two functions a
notch.
v2: Update the kerneldoc even more to explain that these functions
can't be called concurrently, or bad things happen (Chris).
Cc: Dave Airlie <airlied@gmail.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Tested-by: Lyude <lyude@redhat.com>
Reviewed-by: Lyude <lyude@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170111090117.5134-1-daniel.vetter@ffwll.ch
Since commit fe115628d5 ("drm/i915: Implement pwrite without
struct-mutex") the lowlevel pwrite calls are now called without the
protection of struct_mutex, but pwrite_phys was still asserting that it
held the struct_mutex and later tried to drop and relock it.
Fixes: fe115628d5 ("drm/i915: Implement pwrite without struct-mutex")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: <drm-intel-fixes@lists.freedesktop.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170106152240.5793-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
(cherry picked from commit 10466d2a59)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Missed when rebasing patches, I failed to set ret to zero before
starting the unbind loop (which depends upon ret being zero).
Reported-by: Matthew Auld <matthew.william.auld@gmail.com>
Fixes: 9332f3b1b9 ("drm/i915: Combine loops within i915_gem_evict_something")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170105155940.10033-1-chris@chris-wilson.co.uk
Reviewed-by: Matthew Auld <matthew.william.auld@gmail.com>
Cc: <stable@vger.kernel.org> # v4.9+
(cherry picked from commit 121dfbb2a2)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
I noticed that the VT switch doesn't work any longer with a Dell
laptop with 1366x768 eDP when the machine is connected with a DP
monitor. It behaves as if VT were switched, but the graphics remain
frozen. Actually the keyboard works, so I could switch back to VT7
again.
I tried to track down the problem, and encountered a long story until
we reach to this error:
- The machine is booted with video=1366x768 option (the distro
installer seems to add it as default).
- Recently, drm_helper_probe_single_connector_modes() deals with
cmdline modes, and it tries to create a new mode when no
matching mode is found.
- The drm_mode_create_from_cmdline_mode() creates a mode based on
either CVT of GFT according to the given cmdline mode; in our case,
it's 1366x768.
- Since both CVT and GFT can't express the width 1366 due to
alignment, the resultant mode becomes 1368x768, slightly larger than
the given size.
- Later on, the atomic commit is performed, and in
drm_atomic_check_only(), the size of each plane is checked.
- The size check of 1366x768 fails due to the above, and eventually
the whole VT switch fails.
Back in the history, we've had a manual fix-up of 1368x768 in various
places via c09dedb7a5 ("drm/edid: Add a workaround for 1366x768 HD
panel"), but they have been all in drm_edid.c at probing the modes
from EDID. For addressing the problem above, we need a similar hack
to the mode newly created from cmdline, manually adjusting the width
when the expected size is 1366 while we get 1368 instead.
Fixes: eaf99c749d ("drm: Perform cmdline mode parsing during...")
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: http://patchwork.freedesktop.org/patch/msgid/20170109145614.29454-1-tiwai@suse.de
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
After rollover of the IOVA space, we want to get a low IOVA address,
otherwise the the games we play by remembering the last IOVA are
pointless. When we search for a free hole with DRM_MM_SEARCH_DEFAULT,
drm_mm will pop the next entry from the free holes stack, which will
likely be a high IOVA. By using DRM_MM_SEARCH_BELOW we can trick
drm_mm into reversing the search and provide us with a low IOVA.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Wladimir van der Laan <laanwj@gmail.com>
Also update Kconfig help text, explaining things:
Cirrus is obsolete, the hardware was designed in the 90ies
and can't keep up with todays needs. More background:
https://www.kraxel.org/blog/2014/10/qemu-using-cirrus-considered-harmful/
Better alternatives are:
- stdvga (DRM_BOCHS, qemu -vga std, default in qemu 2.2+)
- qxl (DRM_QXL, qemu -vga qxl, works best with spice)
- virtio (VIRTIO_GPU), qemu -vga virtio)
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
virtio uses normal ram as backing storage for the framebuffer, so we
should assign the address to new screen_buffer (added by commit
17a7b0b4d9) instead of screen_base.
Reported-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>