On Mon, Jul 12, 2021 at 6:53 PM Thomas Zimmermann <tzimmermann@xxxxxxx> wrote: > > Hi > > Am 12.07.21 um 13:56 schrieb Sumera Priyadarsini: > > On Mon, Jul 5, 2021 at 1:16 PM Thomas Zimmermann <tzimmermann@xxxxxxx> wrote: > >> > >> Vkms copies each plane's framebuffer into the output buffer; essentially > >> using a shadow buffer. DRM provides struct drm_shadow_plane_state, which > >> handles the details of mapping/unmapping shadow buffers into memory for > >> active planes. > >> > >> Convert vkms to the helpers. Makes vkms use shared code and gives more > >> test exposure to shadow-plane helpers. > >> > >> Thomas Zimmermann (4): > >> drm/gem: Export implementation of shadow-plane helpers > >> drm/vkms: Inherit plane state from struct drm_shadow_plane_state > >> drm/vkms: Let shadow-plane helpers prepare the plane's FB > >> drm/vkms: Use dma-buf mapping from shadow-plane state for composing > >> > >> drivers/gpu/drm/drm_gem_atomic_helper.c | 55 ++++++++++++++++++++++-- > >> drivers/gpu/drm/vkms/vkms_composer.c | 26 ++++++----- > >> drivers/gpu/drm/vkms/vkms_drv.h | 6 ++- > >> drivers/gpu/drm/vkms/vkms_plane.c | 57 ++++++------------------- > >> include/drm/drm_gem_atomic_helper.h | 6 +++ > >> 5 files changed, 86 insertions(+), 64 deletions(-) > >> > >> > >> base-commit: 3d3b5479895dd6dd133571ded4318adf595708ba > >> -- > >> 2.32.0 > >> > > Hi, > > > > Thanks for the patches. The switch to shadow-plane helpers also solved > > a bug that was causing a kernel > > panic during some IGT kms_flip subtests on the vkms virtual hw patch. > > Melissa mention something like that as well and I don't really > understand. Patch 3 removes an error message from the code, but is the > actual bug also gone? Yes, I think so. Earlier, while testing the vkms virtual hw patch, the tests were not just failing, but the vmap fail also preceeded a page fault which required a whole restart. Check these logs around line 303: https://pastebin.pl/view/03b750be. I could be wrong but I think if the same bug was still present, then the kernel panic would also happen even if the error message was not being returned. Cheers, Sumera > > There's little difference between vkms' original code and the shared > helper; except for the order of operations in prepare_fb. The shared > helper synchronizes fences before mapping; vkms mapped first. > > (Maybe the shared helper should warn about failed vmaps as well. But > that's for another patch.) > > Best regards > Thomas > > > > > Tested-by: Sumera Priyadarsini <sylphrenadin@xxxxxxxxx> > > > > Cheers, > > Sumera > > > > -- > Thomas Zimmermann > Graphics Driver Developer > SUSE Software Solutions Germany GmbH > Maxfeldstr. 5, 90409 Nürnberg, Germany > (HRB 36809, AG Nürnberg) > Geschäftsführer: Felix Imendörffer >
