drm/amdgpu: no need to clean debugfs at amdgpu
drm_minor_unregister will invoke drm_debugfs_cleanup
to clean all the child node under primary minor node.
We don't need to invoke amdgpu_debugfs_fini and
amdgpu_debugfs_regs_cleanup to clean agian.
Otherwise, it will raise the NULL pointer like below.
[ 45.046029] BUG: unable to handle kernel NULL pointer dereference at
00000000000000a8
[ 45.047256] PGD 0 P4D 0
[ 45.047713] Oops: 0002 [#1] SMP PTI
[ 45.048198] CPU: 0 PID: 2796 Comm: modprobe Tainted: G W OE 4.18.0-15-generic #16~18.04.1-Ubuntu
[ 45.049538] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
[ 45.050651] RIP: 0010:down_write+0x1f/0x40
[ 45.051194] Code: 90 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb e8 ce d9 ff ff 48 ba 01 00 00 00 ff ff ff ff 48 89 d8 <f0> 48 0f c1 10 85 d2 74 05 e8 53 1c ff ff 65 48 8b 04 25 00 5c 01
[ 45.053702] RSP: 0018:
ffffad8f4133fd40 EFLAGS:
00010246
[ 45.054384] RAX:
00000000000000a8 RBX:
00000000000000a8 RCX:
ffffa011327dd814
[ 45.055349] RDX:
ffffffff00000001 RSI:
0000000000000001 RDI:
00000000000000a8
[ 45.056346] RBP:
ffffad8f4133fd48 R08:
0000000000000000 R09:
ffffffffc0690a00
[ 45.057326] R10:
ffffad8f4133fd58 R11:
0000000000000001 R12:
ffffa0113cff0300
[ 45.058266] R13:
ffffa0113c0a0000 R14:
ffffffffc0c02a10 R15:
ffffa0113e5c7860
[ 45.059221] FS:
00007f60d46f9540(0000) GS:
ffffa0113fc00000(0000) knlGS:
0000000000000000
[ 45.060809] CS: 0010 DS: 0000 ES: 0000 CR0:
0000000080050033
[ 45.061826] CR2:
00000000000000a8 CR3:
0000000136250004 CR4:
00000000003606f0
[ 45.062913] DR0:
0000000000000000 DR1:
0000000000000000 DR2:
0000000000000000
[ 45.064404] DR3:
0000000000000000 DR6:
00000000fffe0ff0 DR7:
0000000000000400
[ 45.065897] Call Trace:
[ 45.066426] debugfs_remove+0x36/0xa0
[ 45.067131] amdgpu_debugfs_ring_fini+0x15/0x20 [amdgpu]
[ 45.068019] amdgpu_debugfs_fini+0x2c/0x50 [amdgpu]
[ 45.068756] amdgpu_pci_remove+0x49/0x70 [amdgpu]
[ 45.069439] pci_device_remove+0x3e/0xc0
[ 45.070037] device_release_driver_internal+0x18a/0x260
[ 45.070842] driver_detach+0x3f/0x80
[ 45.071325] bus_remove_driver+0x59/0xd0
[ 45.071850] driver_unregister+0x2c/0x40
[ 45.072377] pci_unregister_driver+0x22/0xa0
[ 45.073043] amdgpu_exit+0x15/0x57c [amdgpu]
[ 45.073683] __x64_sys_delete_module+0x146/0x280
[ 45.074369] do_syscall_64+0x5a/0x120
[ 45.074916] entry_SYSCALL_64_after_hwframe+0x44/0xa9
v2: remove all debugfs cleanup/fini code at amdgpu
v3: squash in unused variable removal
Signed-off-by: Yintian Tao <yttao@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>