From: Greg Kroah-Hartman gregkh@linuxfoundation.org
From: Holger Hoffstätte holger@applied-asynchrony.com
commit 15e8b95d5f7509e0b09289be8c422c459c9f0412 upstream.
Commit 41401ac67791 added FPU wrappers to dcn21_validate_bandwidth(), which was correct. Unfortunately a nested function alredy contained DC_FP_START()/DC_FP_END() calls, which results in nested FPU context enter/exit and complaints by kernel_fpu_begin_mask(). This can be observed e.g. with 5.10.20, which backported 41401ac67791 and now emits the following warning on boot:
WARNING: CPU: 6 PID: 858 at arch/x86/kernel/fpu/core.c:129 kernel_fpu_begin_mask+0xa5/0xc0 Call Trace: dcn21_calculate_wm+0x47/0xa90 [amdgpu] dcn21_validate_bandwidth_fp+0x15d/0x2b0 [amdgpu] dcn21_validate_bandwidth+0x29/0x40 [amdgpu] dc_validate_global_state+0x3c7/0x4c0 [amdgpu]
The warning is emitted due to the additional DC_FP_START/END calls in patch_bounding_box(), which is inlined into dcn21_calculate_wm(), its only caller. Removing the calls brings the code in line with dcn20 and makes the warning disappear.
Fixes: 41401ac67791 ("drm/amd/display: Add FPU wrappers to dcn21_validate_bandwidth()") Signed-off-by: Holger Hoffstätte holger@applied-asynchrony.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c | 4 ---- 1 file changed, 4 deletions(-)
--- a/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c +++ b/drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c @@ -1058,8 +1058,6 @@ static void patch_bounding_box(struct dc { int i;
- DC_FP_START(); - if (dc->bb_overrides.sr_exit_time_ns) { for (i = 0; i < WM_SET_COUNT; i++) { dc->clk_mgr->bw_params->wm_table.entries[i].sr_exit_time_us = @@ -1084,8 +1082,6 @@ static void patch_bounding_box(struct dc dc->bb_overrides.dram_clock_change_latency_ns / 1000.0; } } - - DC_FP_END(); }
void dcn21_calculate_wm(