From: Tim Huang tim.huang@amd.com

[ Upstream commit 20b5a8f9f4670a8503aa9fa95ca632e77c6bf55d ]

Flexible endpoints use DIGs from available inflexible endpoints, so only the encoders of inflexible links need to be freed. Otherwise, a double free issue may occur when unloading the amdgpu module.

[ 279.190523] RIP: 0010:__slab_free+0x152/0x2f0 [ 279.190577] Call Trace: [ 279.190580] <TASK> [ 279.190582] ? show_regs+0x69/0x80 [ 279.190590] ? die+0x3b/0x90 [ 279.190595] ? do_trap+0xc8/0xe0 [ 279.190601] ? do_error_trap+0x73/0xa0 [ 279.190605] ? __slab_free+0x152/0x2f0 [ 279.190609] ? exc_invalid_op+0x56/0x70 [ 279.190616] ? __slab_free+0x152/0x2f0 [ 279.190642] ? asm_exc_invalid_op+0x1f/0x30 [ 279.190648] ? dcn10_link_encoder_destroy+0x19/0x30 [amdgpu] [ 279.191096] ? __slab_free+0x152/0x2f0 [ 279.191102] ? dcn10_link_encoder_destroy+0x19/0x30 [amdgpu] [ 279.191469] kfree+0x260/0x2b0 [ 279.191474] dcn10_link_encoder_destroy+0x19/0x30 [amdgpu] [ 279.191821] link_destroy+0xd7/0x130 [amdgpu] [ 279.192248] dc_destruct+0x90/0x270 [amdgpu] [ 279.192666] dc_destroy+0x19/0x40 [amdgpu] [ 279.193020] amdgpu_dm_fini+0x16e/0x200 [amdgpu] [ 279.193432] dm_hw_fini+0x26/0x40 [amdgpu] [ 279.193795] amdgpu_device_fini_hw+0x24c/0x400 [amdgpu] [ 279.194108] amdgpu_driver_unload_kms+0x4f/0x70 [amdgpu] [ 279.194436] amdgpu_pci_remove+0x40/0x80 [amdgpu] [ 279.194632] pci_device_remove+0x3a/0xa0 [ 279.194638] device_remove+0x40/0x70 [ 279.194642] device_release_driver_internal+0x1ad/0x210 [ 279.194647] driver_detach+0x4e/0xa0 [ 279.194650] bus_remove_driver+0x6f/0xf0 [ 279.194653] driver_unregister+0x33/0x60 [ 279.194657] pci_unregister_driver+0x44/0x90 [ 279.194662] amdgpu_exit+0x19/0x1f0 [amdgpu] [ 279.194939] __do_sys_delete_module.isra.0+0x198/0x2f0 [ 279.194946] __x64_sys_delete_module+0x16/0x20 [ 279.194950] do_syscall_64+0x58/0x120 [ 279.194954] entry_SYSCALL_64_after_hwframe+0x6e/0x76 [ 279.194980] </TASK>

Reviewed-by: Rodrigo Siqueira rodrigo.siqueira@amd.com Signed-off-by: Tim Huang tim.huang@amd.com Reviewed-by: Roman Li roman.li@amd.com Signed-off-by: Roman Li roman.li@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com [ dc_link_destruct() moved from core/dc_link.c to link/link_factory.c since commit: 54618888d1ea ("drm/amd/display: break down dc_link.c"), so modified the path to apply on 5.15.y ] Signed-off-by: Xiangyu Chen xiangyu.chen@windriver.com Signed-off-by: He Zhe zhe.he@windriver.com --- Verified on the build test --- drivers/gpu/drm/amd/display/dc/core/dc_link.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c index b727bd7e039d..6696372b82f4 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c @@ -79,7 +79,7 @@ static void dc_link_destruct(struct dc_link *link) if (link->panel_cntl) link->panel_cntl->funcs->destroy(&link->panel_cntl);

- if (link->link_enc) { + if (link->link_enc && !link->is_dig_mapping_flexible) { /* Update link encoder resource tracking variables. These are used for * the dynamic assignment of link encoders to streams. Virtual links * are not assigned encoder resources on creation.