Apologies for the delayed response. I wasn’t able to test the patch immediately because I had surgery, so it took me a little longer than expected to get back to this. Thank you for your patience.
I tested the generic patch on the affected MacBookPro11,5 with a Radeon R9 M370X (VERDE). The test was performed with the hardware cursor enabled and without the Mutter software-cursor workaround. Before and after repeated cursor movement, the kernel log remained at zero occurrences of: DC: Cursor address is 0! DC failed to set cursor attributes I also did not observe any cursor disappearance, flickering, or instability during testing. The generic patch appears to fix the issue on this hardware. Tested-by: Ayhan Çiçek [email protected] Thanks, Ayhan 26 Eyl 2026 Cmt 01:24 tarihinde Ayhan Çicek <[email protected]> şunu yazdı: > Thanks, that approach makes sense and looks cleaner than handling > individual ASICs. > I'll test the attached generic patch on the affected MacBookPro11,5 with > the Radeon R9 M370X (VERDE), with the hardware cursor enabled. > I'll verify that the original symptoms do not return and that the kernel > no longer reports: > DC: Cursor address is 0! > DC failed to set cursor attributes > I'll report back with the test results and add my Tested-by if everything > works as expected. > Thanks, > Ayhan > > > Alex Deucher <[email protected]>, 25 Eyl 2026 Cum, 16:19 tarihinde > şunu yazdı: > >> On Fri, Sep 25, 2026 at 3:46 AM Ayhan Çiçek <[email protected]> wrote: >> > >> > The existing MacBook workaround reserves VRAM at address 0 for >> > Polaris ASICs when the iGPU is enabled. This prevents cursor >> > allocations from landing at address 0. >> > >> > A MacBookPro11,5 with Radeon R9 M370X (VERDE) hits the same >> > failure mode. Hardware cursor updates repeatedly log >> > "DC: Cursor address is 0!" followed by >> > "DC failed to set cursor attributes". >> > >> > Extend the existing workaround to CHIP_VERDE. With this change, >> > hardware cursor operation is stable, the cursor errors remain at >> > zero during repeated cursor movement, and cursor disappearance >> > and flicker are no longer observed. >> >> Sounds like this may be consistent for most or all Macs. How about >> something like the attached patch? >> >> Alex >> >> > >> > Signed-off-by: Ayhan Çiçek <[email protected]> >> > --- >> > drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c | 1 + >> > 1 file changed, 1 insertion(+) >> > >> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c >> b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c >> > index 1bf2a42fa..9e7f9cc2b 100644 >> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c >> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.c >> > @@ -1086,6 +1086,7 @@ void amdgpu_gmc_init_vga_resv_regions(struct >> amdgpu_device *adev) >> > case CHIP_RENOIR: >> > adev->mman.keep_stolen_vga_memory = true; >> > break; >> > + case CHIP_VERDE: >> > case CHIP_POLARIS10: >> > case CHIP_POLARIS11: >> > case CHIP_POLARIS12: >> > -- >> > 2.55.0 >> > >> > > > -- > > > Ayhan ÇİÇEK > Software Architect > > +90 532 291 21 62 > http://www.ayhancicek.com > > >
