AMD General Reviewed-by: Kent Russell <[email protected]> ________________________________ From: Kasiviswanathan, Harish <[email protected]> Sent: Friday, 26 June 2026 12:42:11 To: [email protected] <[email protected]>; Russell, Kent <[email protected]> Cc: Kasiviswanathan, Harish <[email protected]> Subject: [PATCH] drm/amdgpu: Fix kernel panic during driver load failure
Avoid kernel panic if MES init fails during driver load. The KIQ ring is falsely marked as ready as ASICs that use MES, KIQ is owned by MES. BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:gfx_v12_1_wait_reg_mem+0x5a/0x1f0 [amdgpu] Call Trace: gfx_v12_1_ring_emit_reg_write_reg_wait+0x1f/0x30 [amdgpu] amdgpu_gmc_fw_reg_write_reg_wait+0xb2/0x190 [amdgpu] amdgpu_gmc_flush_gpu_tlb+0x1cc/0x230 [amdgpu] amdgpu_gart_invalidate_tlb+0x81/0xa0 [amdgpu] amdgpu_gart_unbind+0x72/0x90 [amdgpu] amdgpu_ttm_backend_unbind+0xa4/0xb0 [amdgpu] amdgpu_ttm_tt_unpopulate+0x13/0xd0 [amdgpu] amdttm_tt_unpopulate+0x29/0x70 [amdttm] ttm_bo_put+0x1eb/0x360 [amdttm] amdgpu_bo_free_kernel+0xf9/0x1f0 [amdgpu] amdgpu_ih_ring_fini+0x5a/0x90 [amdgpu] amdgpu_irq_fini_hw+0x58/0x80 [amdgpu] amdgpu_device_fini_hw+0x4e0/0x5b0 [amdgpu] amdgpu_driver_load_kms+0x60/0xa0 [amdgpu] amdgpu_pci_probe+0x28e/0x6d0 [amdgpu] pci_device_probe+0x19f/0x220 really_probe+0x1ed/0x340 driver_probe_device+0x1e/0x80 __driver_attach+0xd3/0x1a0 bus_for_each_dev+0x68/0xa0 bus_add_driver+0x19f/0x270 driver_register+0x5d/0xf0 do_one_initcall+0xac/0x200 do_init_module+0x1ec/0x280 __se_sys_finit_module+0x2de/0x310 do_syscall_64+0x6a/0x250 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Signed-off-by: Harish Kasiviswanathan <[email protected]> --- drivers/gpu/drm/amd/amdgpu/gfx_v12_0.c | 13 +++++++++++-- drivers/gpu/drm/amd/amdgpu/gfx_v12_1.c | 13 +++++++++++-- 2 files changed, 22 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v12_0.c b/drivers/gpu/drm/amd/amdgpu/gfx_v12_0.c index cd6c1b6f8894..c765af54669c 100644 --- a/drivers/gpu/drm/amd/amdgpu/gfx_v12_0.c +++ b/drivers/gpu/drm/amd/amdgpu/gfx_v12_0.c @@ -3524,10 +3524,19 @@ static int gfx_v12_0_cp_resume(struct amdgpu_device *adev) gfx_v12_0_cp_gfx_enable(adev, true); } - if (adev->enable_mes_kiq && adev->mes.kiq_hw_init) + if (adev->enable_mes_kiq && adev->mes.kiq_hw_init) { r = amdgpu_mes_kiq_hw_init(adev, 0); - else + /* + * With MES, GFX KIQ ring is owned by the MES and is never + * initialized/used directly by the driver, so it must + * not be left flagged as ready. mes_v12_0_hw_init() clears + * but clear here if MES init fails + */ + if (r) + adev->gfx.kiq[0].ring.sched.ready = false; + } else { r = gfx_v12_0_kiq_resume(adev); + } if (r) return r; diff --git a/drivers/gpu/drm/amd/amdgpu/gfx_v12_1.c b/drivers/gpu/drm/amd/amdgpu/gfx_v12_1.c index aaa8f4212a15..e87f1baf5cb6 100644 --- a/drivers/gpu/drm/amd/amdgpu/gfx_v12_1.c +++ b/drivers/gpu/drm/amd/amdgpu/gfx_v12_1.c @@ -2549,10 +2549,19 @@ static int gfx_v12_1_xcc_cp_resume(struct amdgpu_device *adev, uint16_t xcc_mask gfx_v12_1_xcc_cp_compute_enable(adev, true, xcc_id); - if (adev->enable_mes_kiq && adev->mes.kiq_hw_init) + if (adev->enable_mes_kiq && adev->mes.kiq_hw_init) { r = amdgpu_mes_kiq_hw_init(adev, xcc_id); - else + /* + * With MES, GFX KIQ ring is owned by the MES and is never + * initialized/used directly by the driver, so it must + * not be left flagged as ready. mes_v12_0_hw_init() clears + * but clear here if MES init fails + */ + if (r) + adev->gfx.kiq[xcc_id].ring.sched.ready = false; + } else { r = gfx_v12_1_xcc_kiq_resume(adev, xcc_id); + } if (r) return r; -- 2.43.0
