[PATCH] drm/amdgpu: set the right sg limitation

[Prike Liang]

The driver needs to set the correct max_segment_size;
otherwise debug_dma_map_sg() will complain about the
over-mapping of the AMDGPU sg segment as following:

WARNING: CPU: 6 PID: 1964 at kernel/dma/debug.c:1178 debug_dma_map_sg+0x2dc/0x370
[  364.049444] Modules linked in: veth amdgpu(OE) amdxcp drm_exec gpu_sched drm_buddy drm_ttm_helper ttm(OE) drm_suballoc_helper drm_display_helper drm_kms_helper i2c_algo_bit rpcsec_gss_krb5 auth_rpcgss nfsv4 nfs lockd grace netfs xt_conntrack xt_MASQUERADE nf_conntrack_netlink xfrm_user xfrm_algo iptable_nat xt_addrtype iptable_filter br_netfilter nvme_fabrics overlay nfnetlink_cttimeout nfnetlink openvswitch nsh nf_conncount nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c bridge stp llc amd_atl intel_rapl_msr intel_rapl_common sunrpc sch_fq_codel snd_hda_codec_realtek snd_hda_codec_generic snd_hda_scodec_component snd_hda_codec_hdmi snd_hda_intel snd_intel_dspcfg edac_mce_amd binfmt_misc snd_hda_codec snd_pci_acp6x snd_hda_core snd_acp_config snd_hwdep snd_soc_acpi kvm_amd snd_pcm kvm snd_seq_midi snd_seq_midi_event crct10dif_pclmul ghash_clmulni_intel sha512_ssse3 snd_rawmidi sha256_ssse3 sha1_ssse3 aesni_intel snd_seq nls_iso8859_1 crypto_simd snd_seq_device cryptd snd_timer rapl input_leds snd
[  364.049532]  ipmi_devintf wmi_bmof ccp serio_raw k10temp sp5100_tco soundcore ipmi_msghandler cm32181 industrialio mac_hid msr parport_pc ppdev lp parport drm efi_pstore ip_tables x_tables pci_stub crc32_pclmul nvme ahci libahci i2c_piix4 r8169 nvme_core i2c_designware_pci realtek i2c_ccgx_ucsi video wmi hid_generic cdc_ether usbnet usbhid hid r8152 mii
[  364.049576] CPU: 6 PID: 1964 Comm: rocminfo Tainted: G           OE      6.10.0-custom #492
[  364.049579] Hardware name: AMD Majolica-RN/Majolica-RN, BIOS RMJ1009A 06/13/2021
[  364.049582] RIP: 0010:debug_dma_map_sg+0x2dc/0x370
[  364.049585] Code: 89 4d b8 e8 36 b1 86 00 8b 4d b8 48 8b 55 b0 44 8b 45 a8 4c 8b 4d a0 48 89 c6 48 c7 c7 00 4b 74 bc 4c 89 4d b8 e8 b4 73 f3 ff <0f> 0b 4c 8b 4d b8 8b 15 c8 2c b8 01 85 d2 0f 85 ee fd ff ff 8b 05
[  364.049588] RSP: 0018:ffff9ca600b57ac0 EFLAGS: 00010286
[  364.049590] RAX: 0000000000000000 RBX: ffff88b7c132b0c8 RCX: 0000000000000027
[  364.049592] RDX: ffff88bb0f521688 RSI: 0000000000000001 RDI: ffff88bb0f521680
[  364.049594] RBP: ffff9ca600b57b20 R08: 000000000000006f R09: ffff9ca600b57930
[  364.049596] R10: ffff9ca600b57928 R11: ffffffffbcb46328 R12: 0000000000000000
[  364.049597] R13: 0000000000000001 R14: ffff88b7c19c0700 R15: ffff88b7c9059800
[  364.049599] FS:  00007fb2d3516e80(0000) GS:ffff88bb0f500000(0000) knlGS:0000000000000000
[  364.049601] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  364.049603] CR2: 000055610bd03598 CR3: 00000001049f6000 CR4: 0000000000350ef0
[  364.049605] Call Trace:
[  364.049607]  <TASK>
[  364.049609]  ? show_regs+0x6d/0x80
[  364.049614]  ? __warn+0x8c/0x140
[  364.049618]  ? debug_dma_map_sg+0x2dc/0x370
[  364.049621]  ? report_bug+0x193/0x1a0
[  364.049627]  ? handle_bug+0x46/0x80
[  364.049631]  ? exc_invalid_op+0x1d/0x80
[  364.049635]  ? asm_exc_invalid_op+0x1f/0x30
[  364.049642]  ? debug_dma_map_sg+0x2dc/0x370
[  364.049647]  __dma_map_sg_attrs+0x90/0xe0
[  364.049651]  dma_map_sgtable+0x25/0x40
[  364.049654]  amdgpu_bo_move+0x59a/0x850 [amdgpu]
[  364.049935]  ? srso_return_thunk+0x5/0x5f
[  364.049939]  ? amdgpu_ttm_tt_populate+0x5d/0xc0 [amdgpu]
[  364.050095]  ttm_bo_handle_move_mem+0xc3/0x180 [ttm]
[  364.050103]  ttm_bo_validate+0xc1/0x160 [ttm]
[  364.050108]  ? amdgpu_ttm_tt_get_user_pages+0xe5/0x1b0 [amdgpu]
[  364.050263]  amdgpu_amdkfd_gpuvm_alloc_memory_of_gpu+0xa12/0xc90 [amdgpu]
[  364.050473]  kfd_ioctl_alloc_memory_of_gpu+0x16b/0x3b0 [amdgpu]
[  364.050680]  kfd_ioctl+0x3c2/0x530 [amdgpu]
[  364.050866]  ? __pfx_kfd_ioctl_alloc_memory_of_gpu+0x10/0x10 [amdgpu]
[  364.051054]  ? srso_return_thunk+0x5/0x5f
[  364.051057]  ? tomoyo_file_ioctl+0x20/0x30
[  364.051063]  __x64_sys_ioctl+0x9c/0xd0
[  364.051068]  x64_sys_call+0x1219/0x20d0
[  364.051073]  do_syscall_64+0x51/0x120
[  364.051077]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  364.051081] RIP: 0033:0x7fb2d2f1a94f

Signed-off-by: Prike Liang <Prike.Liang at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index 0637414fc70e..78e6e72143e3 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -1851,6 +1851,7 @@ int amdgpu_ttm_init(struct amdgpu_device *adev)
 
 	mutex_init(&adev->mman.gtt_window_lock);
 
+	dma_set_max_seg_size(adev->dev, dma_max_mapping_size(adev->dev) ?: UINT_MAX);
 	/* No others user of address space so set it to 0 */
 	r = ttm_device_init(&adev->mman.bdev, &amdgpu_bo_driver, adev->dev,
 			       adev_to_drm(adev)->anon_inode->i_mapping,
-- 
2.34.1