From: Sam Bobroff <sbobroff@xxxxxxxxxxxxx> [ Upstream commit 3d0e3ce52ce3eb4b9de3caf9c38dbb5a4d3e13c3 ] The INTERRUPT_CNTL2 register expects a valid DMA address, but is currently set with a GPU MC address. This can cause problems on systems that detect the resulting DMA read from an invalid address (found on a Power8 guest). Instead, use the DMA address of the dummy page because it will always be safe. Fixes: 27ae10641e9c ("drm/amdgpu: add interupt handler implementation for si v3") Signed-off-by: Sam Bobroff <sbobroff@xxxxxxxxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/amd/amdgpu/si_ih.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/si_ih.c b/drivers/gpu/drm/amd/amdgpu/si_ih.c index 60dad63098a2a..e40a3fbc3e760 100644 --- a/drivers/gpu/drm/amd/amdgpu/si_ih.c +++ b/drivers/gpu/drm/amd/amdgpu/si_ih.c @@ -62,7 +62,8 @@ static int si_ih_irq_init(struct amdgpu_device *adev) u64 wptr_off; si_ih_disable_interrupts(adev); - WREG32(INTERRUPT_CNTL2, adev->irq.ih.gpu_addr >> 8); + /* set dummy read address to dummy page address */ + WREG32(INTERRUPT_CNTL2, adev->dummy_page_addr >> 8); interrupt_cntl = RREG32(INTERRUPT_CNTL); interrupt_cntl &= ~IH_DUMMY_RD_OVERRIDE; interrupt_cntl &= ~IH_REQ_NONSNOOP_EN; -- 2.20.1