On Wed, Aug 30, 2023 at 11:53:29AM -0700, Chia-I Wu wrote: > On Sun, Jul 23, 2023 at 6:24 PM Sasha Levin <sashal@xxxxxxxxxx> wrote: > > > > From: Lang Yu <Lang.Yu@xxxxxxx> > > > > [ Upstream commit 187916e6ed9d0c3b3abc27429f7a5f8c936bd1f0 ] > > > > When using cpu to update page tables, vm update fences are unused. > > Install stub fence into these fence pointers instead of NULL > > to avoid NULL dereference when calling dma_fence_wait() on them. > > > > Suggested-by: Christian König <christian.koenig@xxxxxxx> > > Signed-off-by: Lang Yu <Lang.Yu@xxxxxxx> > > Reviewed-by: Christian König <christian.koenig@xxxxxxx> > > Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> > > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> > > --- > > drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 6 ++++-- > > 1 file changed, 4 insertions(+), 2 deletions(-) > > We start getting this warning spew on chromeos, likely from > dma_fence_is_later because the stub fence is on a different timeline: > > [ 273.334767] WARNING: CPU: 1 PID: 13383 at > include/linux/dma-fence.h:478 amdgpu_sync_keep_later+0x95/0xbd > [ 273.334769] Modules linked in: snd_seq_dummy snd_seq snd_seq_device > bridge stp llc tun vhost_vsock vhost vhost_iotlb > vmw_vsock_virtio_transport_common vsock 8021q veth lzo_rle > lzo_compress zram uinput snd_acp_sof_mach snd_acp_mach snd_soc_dmic > xt_cgroup rfcomm xt_MASQUERADE cmac algif_hash algif_skcipher af_alg > btusb btrtl btintel btbcm rtw89_8852ae rtw89_pci rtw89_8852a > rtw89_core snd_sof_amd_renoir snd_sof_xtensa_dsp snd_sof_amd_acp > snd_acp_pci snd_acp_config snd_soc_acpi snd_pci_acp3x snd_sof_pci > snd_sof snd_hda_codec_hdmi snd_sof_utils snd_hda_intel mac80211 > snd_intel_dspcfg snd_hda_codec cros_ec_typec snd_hwdep roles > snd_hda_core typec snd_soc_rt5682s snd_soc_rt1019 snd_soc_rl6231 > ip6table_nat i2c_piix4 fuse bluetooth ecdh_generic ecc cfg80211 > iio_trig_sysfs cros_ec_lid_angle cros_ec_sensors cros_ec_sensors_core > industrialio_triggered_buffer kfifo_buf industrialio cros_ec_sensorhub > r8153_ecm cdc_ether usbnet r8152 mii uvcvideo videobuf2_vmalloc > videobuf2_memops videobuf2_v4l2 > [ 273.334795] videobuf2_common joydev > [ 273.334799] CPU: 1 PID: 13383 Comm: chrome:cs0 Tainted: G W > 5.10.192-23384-g3d3f0f0c5e4f #1 > fe1e7e3b7510aa7b8e01701478119255f825a36f > [ 273.334800] Hardware name: Google Dewatt/Dewatt, BIOS > Google_Dewatt.14500.347.0 03/30/2023 > [ 273.334802] RIP: 0010:amdgpu_sync_keep_later+0x95/0xbd > [ 273.334804] Code: 00 00 b8 01 00 00 00 f0 0f c1 43 38 85 c0 74 26 > 8d 48 01 09 c1 78 24 49 89 1e 5b 41 5e 5d c3 cc cc cc cc e8 4a 94 ac > ff eb ce <0f> 0b 49 8b 06 48 85 c0 75 af eb c2 be 02 00 00 00 48 8d 7b > 38 e8 > [ 273.334805] RSP: 0018:ffffb222c1817b50 EFLAGS: 00010293 > [ 273.334807] RAX: ffffffff89bfc838 RBX: ffff8aa425e9ed00 RCX: 0000000000000000 > [ 273.334808] RDX: ffff8aa426156a98 RSI: ffff8aa425e9ed00 RDI: ffff8aa432518918 > [ 273.334810] RBP: ffffb222c1817b60 R08: ffff8aa43ca6c0a0 R09: ffff8aa33af3c9a0 > [ 273.334811] R10: fffffcf8c5986600 R11: ffffffff87a00fce R12: 0000000000000098 > [ 273.334812] R13: 00000000005e2a00 R14: ffff8aa432518918 R15: 0000000000000000 > [ 273.334814] FS: 00007e70f8694640(0000) GS:ffff8aa4e6080000(0000) > knlGS:0000000000000000 > [ 273.334816] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 273.334817] CR2: 00007e70ea049020 CR3: 0000000178e6e000 CR4: 0000000000750ee0 > [ 273.334818] PKRU: 55555554 > [ 273.334819] Call Trace: > [ 273.334822] ? __warn+0xa3/0x131 > [ 273.334824] ? amdgpu_sync_keep_later+0x95/0xbd > [ 273.334826] ? report_bug+0x97/0xfa > [ 273.334829] ? handle_bug+0x41/0x66 > [ 273.334832] ? exc_invalid_op+0x1b/0x72 > [ 273.334835] ? asm_exc_invalid_op+0x12/0x20 > [ 273.334837] ? native_sched_clock+0x9a/0x9a > [ 273.334840] ? amdgpu_sync_keep_later+0x95/0xbd > [ 273.334843] amdgpu_sync_vm_fence+0x23/0x39 > [ 273.334846] amdgpu_cs_ioctl+0x1782/0x1e56 > [ 273.334851] ? amdgpu_cs_report_moved_bytes+0x5f/0x5f > [ 273.334854] drm_ioctl_kernel+0xdf/0x150 > [ 273.334858] drm_ioctl+0x1f5/0x3d2 > [ 273.334928] ? amdgpu_cs_report_moved_bytes+0x5f/0x5f > [ 273.334932] amdgpu_drm_ioctl+0x49/0x81 > [ 273.334935] __x64_sys_ioctl+0x7d/0xc8 > [ 273.334937] do_syscall_64+0x42/0x54 > [ 273.334939] entry_SYSCALL_64_after_hwframe+0x4a/0xaf > [ 273.334941] RIP: 0033:0x7e70ff797649 > [ 273.334943] Code: 04 25 28 00 00 00 48 89 45 c8 31 c0 48 8d 45 10 > c7 45 b0 10 00 00 00 48 89 45 b8 48 8d 45 d0 48 89 45 c0 b8 10 00 00 > 00 0f 05 <41> 89 c0 3d 00 f0 ff ff 77 1d 48 8b 45 c8 64 48 2b 04 25 28 > 00 00 > [ 273.334945] RSP: 002b:00007e70f8693170 EFLAGS: 00000246 ORIG_RAX: > 0000000000000010 > [ 273.334947] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007e70ff797649 > [ 273.334948] RDX: 00007e70f8693248 RSI: 00000000c0186444 RDI: 0000000000000013 > [ 273.334950] RBP: 00007e70f86931c0 R08: 00007e70f8693350 R09: 00007e70f8693340 > [ 273.334951] R10: 000000000000000a R11: 0000000000000246 R12: 00000000c0186444 > [ 273.334952] R13: 00007e70f8693380 R14: 00007e70f8693248 R15: 0000000000000013 > [ 273.334954] ---[ end trace fc066a0fcea39e8c ]--- Thanks, I'll go revert this now. greg k-h