On 11/9/25 04:29, Yiwei Zhang wrote: > On Sat, Nov 8, 2025 at 4:06 AM Yiwei Zhang <[email protected]> wrote: >> >> On Tue, Nov 4, 2025 at 2:02 AM Pelloux-Prayer, Pierre-Eric >> <[email protected]> wrote: >>> >>> [Public] >>> >>> Hi, >>> >>> The whole series is Acked-by: Pierre-Eric Pelloux-Prayer >>> <[email protected]> >>> >>> Thanks a lot Dmitry! >>> >>> Pierre-Eric >>> >>> ________________________________ >>> From: Dmitry Osipenko <[email protected]> >>> Sent: Tuesday, October 21, 2025 1:39 AM >>> To: Akihiko Odaki <[email protected]>; Huang, Ray >>> <[email protected]>; Marc-André Lureau <[email protected]>; >>> Philippe Mathieu-Daudé <[email protected]>; Gerd Hoffmann >>> <[email protected]>; Alex Bennée <[email protected]>; Pelloux-Prayer, >>> Pierre-Eric <[email protected]>; Michael S . Tsirkin >>> <[email protected]>; Paolo Bonzini <[email protected]> >>> Cc: Gert Wollny <[email protected]>; [email protected] >>> <[email protected]>; Gurchetan Singh <[email protected]>; >>> Alyssa Ross <[email protected]>; Roger Pau Monné <[email protected]>; >>> Deucher, Alexander <[email protected]>; Stabellini, Stefano >>> <[email protected]>; Koenig, Christian <[email protected]>; >>> Ragiadakou, Xenia <[email protected]>; Huang, Honglei1 >>> <[email protected]>; Zhang, Julia <[email protected]>; Chen, Jiqian >>> <[email protected]>; Rob Clark <[email protected]>; Yiwei Zhang >>> <[email protected]>; Sergio Lopez Pascual <[email protected]> >>> Subject: [PATCH v14 00/10] Support virtio-gpu DRM native context >>> >>> This patchset adds DRM native context support to VirtIO-GPU on QEMU. >>> >>> Contarary to Virgl and Venus contexts that mediates high level GFX APIs, >>> DRM native context [1] mediates lower level kernel driver UAPI, which >>> reflects in a less CPU overhead and less/simpler code needed to support it. >>> DRM context consists of a host and guest parts that have to be implemented >>> for each GPU driver. On a guest side, DRM context presents a virtual GPU as >>> a real/native host GPU device for GL/VK applications. >>> >>> [1] https://www.youtube.com/watch?v=9sFP_yddLLQ >>> >>> Today there are four DRM native context drivers existing in a wild: >>> >>> - Freedreno (Qualcomm SoC GPUs), completely upstreamed >>> - AMDGPU, completely upstreamed >>> - Intel (i915), merge requests are opened >>> - Asahi (Apple SoC GPUs), partially merged upstream >>> >>> # How to try out DRM context: >>> >>> 1. DRM context uses host blobs and on host requires v6.13 or newer version >>> of Linux kernel that contains necessary KVM fixes. >>> >>> 2. Use latest available Mesa (both guest and host) and libvirglrenderer >>> versions. On guest, build Mesa with enabled virtio native context support. >>> >>> 3. On guest, use latest Linux kernel v6.14 or newer. >>> >>> Example QEMU cmdline that enables DRM context: >>> >>> qemu-system-x86_64 -device >>> virtio-vga-gl,hostmem=4G,blob=on,drm_native_context=on \ >>> -machine q35,accel=kvm -m 8G >>> >>> # Notes about known problems: >>> >>> 1. DRM contexts are mapping host blobs extensively and these mapping >>> operations work slowly in QEMU. We will need to optimize hostmem >>> unmapping that currently happens in a deffered RCU work, blocking >>> GPU for a substantial time. WIP fixes available at [2][3]. >>> >>> [2] >>> https://lore.kernel.org/qemu-devel/[email protected]/ >>> [3] >>> https://lore.kernel.org/qemu-devel/[email protected]/ >>> >>> 2. Linux kernel virtio-gpu driver doesn't limit display refresh rate, >>> causing poor performance. Fix availalble in drm-misc-next tree [4] >>> and should land upstream with v6.19+ kernel. >>> >>> [4] >>> https://gitlab.freedesktop.org/drm/misc/kernel/-/commit/a036f5fceedb9fbd715565fef7b824a121503de7 >>> >>> 3. Xorg on guest creates initial dumb buffer that is a vrend buffer, which >>> can't be re-used by native contexts. This may cause drawing artifacts. >>> Boot kernel with disabled fbdev using drm_client_lib.active="" kernel >>> cmdline parameter to work around the issue. >>> >>> Wayland on guest isn't affected by this issue. >>> >>> Changelog: >>> >>> v14:- Rebased on top of recent QEMU staging tree. >>> >>> - DRM native context in QEMU now requires virglrenderer v1.2.0+ >>> containing fix for async-fencing not working after guest reboot. >>> >>> - Updated doc patch with new Asahi nctx rquirements info. Asahi >>> support landed to virglrenderer v1.2.0. >>> >>> v13:- Updated Asahi nctx MR link in the doc patch. Old MR was closed >>> and new opened. >>> >>> - Fixed compiler warning about unused variable when using older >>> virglrenderer version. >>> >>> v12:- Rebased on top of recent QEMU/staging and a fix from Yiwei Zhang: >>> >>> >>> https://lore.kernel.org/qemu-devel/[email protected]/ >>> >>> - Async-fence and native context features now require virglrenderer > >>> 1.1.1 >>> that contains fix needed for resetting virtio-gpu-gl properly on QEMU >>> reboot: >>> >>> >>> https://gitlab.freedesktop.org/virgl/virglrenderer/-/commit/6f4681ff09cb17aa2d6715dbc6034eb3abe5711d >>> >>> - Added r-b from Akihiko Odaki to the doc patch. >>> >>> - Corrected resetting of async fences list that was done on scanout >>> reset in v11 instead of virtio-gpu reset. >>> >>> v11:- Added column for libvirglrenderer host requrements versions and >>> corrected Asahi kernel link. Suggested by Akihiko Odaki. >>> >>> v10:- Added links to Asahi and i915 virglrenderer MRs, link to Asahi host >>> kernel. Suggested by Akihiko Odaki. >>> >>> - Renamed gfxstream guest requrements table's colum to match the host >>> requirements table. Suggested by Akihiko Odaki. >>> >>> v9: - Updated doc patch by addresing review comments from Akihiko Odaki. >>> Made kernel requirements section specific to guest kernel and >>> removed reference to host requirements. Removed examples of >>> external projects' build flags. >>> >>> - Added guest kernel minimum versions to the guest requirements table. >>> >>> v8: - Addressed review comments from Akihiko Odaki on the doc patch. >>> >>> - Added r-bs from Akihiko Odaki on the doc patches. >>> >>> - Extended vrend doc with info about hostmem requirement for GL 4.6 >>> >>> v7: - Added r-b from Alex Bennée to the async fencing patch. >>> >>> - Updated virtio-gpu doc patch with addressed review comments >>> from Akihiko Odaki. >>> >>> v6: - Fixed compilation warning using older version of virglrenderer, >>> which wasn't fixed properly in v5. >>> >>> - Added t-bs from Alex Bennée. >>> >>> - Added patches to improve virgl/venus doc by adding links >>> to the Mesa doc as was suggested by Akihiko Odaki. >>> >>> - Updated patch that documents guest/host requirements. Added >>> links to Asahi nctx and reworked the doc structure by adding >>> requirements to each context-type section instead of having >>> one big blob or requirements, which was objected by Akihiko Odaki. >>> >>> v5: - Added r-bs from Akihiko Odaki. >>> >>> - Added acks from Michael Tsirkin. >>> >>> - Fixed compilation warning using older version of virglrenderer that >>> was reported by Alex Bennée. Noticed that I need to keep old >>> virgl_write_fence() code around for the older virglrenderer in >>> "Support asynchronous fencing" patch, so added it back and verified >>> that old virglrenderer works properly. >>> >>> - Added new patch from Alex Bennée that adds more virtio-gpu >>> documentation with a couple corrections and additions to it from me. >>> >>> - Rebased patches on top of latest staging tree. >>> >>> v4: - Improved SDL2/dmabuf patch by reusing existing Meson X11 config >>> option, better handling EGL error and extending comment telling >>> that it's safe to enable SDL2 EGL preference hint. As was suggested >>> by Akihiko Odaki. >>> >>> - Replaced another QSLIST_FOREACH_SAFE with QSLIST_EMPTY+FIRST in >>> the async-fencing patch for more consistency of the code. As was >>> suggested by Akihiko Odaki. >>> >>> - Added missing braces around if-statement that was spotted by >>> Alex Bennée. >>> >>> - Renamed 'drm=on' option of virtio-gpu-gl device to >>> 'drm_native_context=on' for more clarity as was suggested by >>> Alex Bennée. Haven't added added new context-type option that >>> was also proposed by Alex, might do it with a separate patch. >>> This context-type option will duplicate and depecate existing >>> options, but in a longer run likely will be worthwhile adding >>> it. >>> >>> - Dropped Linux headers-update patch as headers has been updated >>> in the staging tree. >>> >>> v3: - Improved EGL presence-check code on X11 systems for the SDL2 >>> hint that prefers EGL over GLX by using better ifdefs and checking >>> Xlib presence at a build time to avoid build failure if lib SDL2 >>> and system are configured with a disabled X11 support. Also added >>> clarifying comment telling that X11 hint doesn't affect Wayland >>> systems. Suggested by Akihiko Odaki. >>> >>> - Corrected strerror(err) that used negative error where it should >>> be positive and vice versa that was caught by Akihiko Odaki. Added >>> clarifying comment for the case where we get positive error code >>> from virglrenderer that differs from other virglrenderer API >>> functions. >>> >>> - Improved QSLIST usage by dropping mutex protecting the async fence >>> list and using atomic variant of QSLIST helpers instead. Switched away >>> from using FOREACH helper to improve readability of the code, showing >>> that we don't precess list in unoptimal way. Like was suggested by >>> Akihiko Odaki. >>> >>> - Updated patchset base to Venus v18. >>> >>> v2: - Updated SDL2-dmabuf patch by making use of error_report() and >>> checking presense of X11+EGL in the system before making SDL2 >>> to prefer EGL backend over GLX, suggested by Akihiko Odaki. >>> >>> - Improved SDL2's dmabuf-presence check that wasn't done properly >>> in v1, where EGL was set up only after first console was fully >>> inited, and thus, SDL's display .has_dmabuf callback didn't work >>> for the first console. Now dmabuf support status is pre-checked >>> before console is registered. >>> >>> - Updated commit description of the patch that fixes SDL2's context >>> switching logic with a more detailed explanation of the problem. >>> Suggested by Akihiko Odaki. >>> >>> - Corrected rebase typo in the async-fencing patch and switched >>> async-fencing to use a sigle-linked list instead of the double, >>> as was suggested by Akihiko Odaki. >>> >>> - Replaced "=true" with "=on" in the DRM native context documentation >>> example and made virtio_gpu_virgl_init() to fail with a error message >>> if DRM context can't be initialized instead of giving a warning >>> message, as was suggested by Akihiko Odaki. >>> >>> - Added patchew's dependecy tag to the cover letter as was suggested by >>> Akihiko Odaki. >>> >>> Alex Bennée (1): >>> docs/system: virtio-gpu: Document host/guest requirements >>> >>> Dmitry Osipenko (8): >>> ui/sdl2: Restore original context after new context creation >>> virtio-gpu: Handle virgl fence creation errors >>> virtio-gpu: Support asynchronous fencing >>> virtio-gpu: Support DRM native context >>> ui/sdl2: Don't disable scanout when display is refreshed >>> ui/gtk: Don't disable scanout when display is refreshed >>> docs/system: virtio-gpu: Add link to Mesa VirGL doc >>> docs/system: virtio-gpu: Update Venus link >>> >>> Pierre-Eric Pelloux-Prayer (1): >>> ui/sdl2: Implement dpy dmabuf functions >>> >>> docs/system/devices/virtio-gpu.rst | 116 +++++++++++++++++- >>> hw/display/virtio-gpu-gl.c | 7 ++ >>> hw/display/virtio-gpu-virgl.c | 185 ++++++++++++++++++++++++++++- >>> hw/display/virtio-gpu.c | 15 +++ >>> include/hw/virtio/virtio-gpu.h | 14 +++ >>> include/ui/sdl2.h | 7 ++ >>> meson.build | 8 +- >>> ui/gtk-egl.c | 1 - >>> ui/gtk-gl-area.c | 1 - >>> ui/sdl2-gl.c | 70 ++++++++++- >>> ui/sdl2.c | 42 +++++++ >>> 11 files changed, 449 insertions(+), 17 deletions(-) >>> >>> -- >>> 2.51.0 >>> >> >> The whole series looks good to me, and Tested-by: Yiwei Zhang >> <[email protected]> > > Just to clarify. My testing is done with venus + virgl to verify async > fence cb in QEMU is working as intended.
Thanks for the review and testing! -- Best regards, Dmitry
