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R . A . Prado" , Hans Verkuil , AngeloGioacchino Del Regno , Benjamin Gaignard , Nathan Hebert , Irui Wang Cc: Hsin-Yi Wang , Fritz Koenig , Daniel Vetter , Steve Cho , linux-media@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, Project_Global_Chrome_Upstream_Group@mediatek.com, Steve Cho Date: Mon, 26 Feb 2024 16:32:37 -0500 In-Reply-To: References: <20240222092609.31382-1-yunfei.dong@mediatek.com> <20240222092609.31382-2-yunfei.dong@mediatek.com> Autocrypt: addr=nicolas.dufresne@collabora.com; prefer-encrypt=mutual; keydata=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 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.50.4 (3.50.4-1.fc39) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Hi Yunfei, Le lundi 26 f=C3=A9vrier 2024 =C3=A0 14:39 -0500, Nicolas Dufresne a =C3=A9= crit=C2=A0: > Hi, >=20 > Le jeudi 22 f=C3=A9vrier 2024 =C3=A0 17:26 +0800, Yunfei Dong a =C3=A9cri= t=C2=A0: > > The ctx_list will be deleted when scp getting unexpected behavior, then= the > > ctx_list->next will be NULL, the kernel driver maybe access NULL pointe= r in > > function vpu_dec_ipi_handler when going through each context, then rebo= ot. > >=20 > > Need to add lock to protect the ctx_list to make sure the ctx_list->nex= t isn't > > NULL pointer. >=20 > The cited crash no longer occurs for me, but it still sometimes crashes w= hile > the SCP being rebooted. I think this patch can still go in, as it overall > improves the situation. >=20 > Meanwhile, here's my stress test using GStreamer and stream downloaded by > fluster. I call this script few times this way as it does not always cras= h. The > test just keep starting decode sessions and terminate them after 2 second= s. It > is highly parallel. Using too low number does not reproduce the crash, us= ing too > high number leads to alloc failure, which wasn't the goal of this test. I just sent=C2=A0a fix for that crash, it was limited to HEVC. https://lore.kernel.org/all/20240226211954.400891-1-nicolas.dufresne@collab= ora.com/ With this applied, the kernel no longer crash. But the SCP get reset every-= time I run the script below. Will you be able to provide a firmware (or driver i= f that turns out to the issue) for this ? regards, Nicolas >=20 > ./mtk-vcodec-crash.sh 100 >=20 > Script code: > *** > #!/bin/bash >=20 > test() { > gst-launch-1.0 --no-fault filesrc location=3DTILES_B_Cisco_1.bin ! h265p= arse ! v4l2slh265dec ! fakevideosink & > pid=3D$! >=20 > sleep 2 > kill $pid > } >=20 > for i in $(seq 1 $1) > do > test & > done >=20 > wait > *** >=20 > The kernel Crash: > [ 93.261248] Unable to handle kernel NULL pointer dereference at virtua= l > address 0000000000000008 > [ 93.270056] Mem abort info: > [ 93.272880] ESR =3D 0x0000000096000004 > [ 93.276804] EC =3D 0x25: DABT (current EL), IL =3D 32 bits > [ 93.282233] SET =3D 0, FnV =3D 0 > [ 93.285372] EA =3D 0, S1PTW =3D 0 > [ 93.288561] FSC =3D 0x04: level 0 translation fault > [ 93.293493] Data abort info: > [ 93.296424] ISV =3D 0, ISS =3D 0x00000004, ISS2 =3D 0x00000000 > [ 93.301920] CM =3D 0, WnR =3D 0, TnD =3D 0, TagAccess =3D 0 > [ 93.306977] GCS =3D 0, Overlay =3D 0, DirtyBit =3D 0, Xs =3D 0 > [ 93.312321] user pgtable: 4k pages, 48-bit VAs, pgdp=3D0000000168daf00= 0 > [ 93.318790] [0000000000000008] pgd=3D0000000000000000, p4d=3D000000000= 0000000 > [ 93.325588] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP > [ 93.331842] Modules linked in: mt7921e mt7921_common mt792x_lib > mt76_connac_lib mt76 mac80211 btusb btintel mtk_vcodec_dec_hw btmtk btrtl > mtk_vcodec_dec btbcm cfg80211 bluetooth snd_sof_mt8195 mtk_vcodec_enc > mtk_adsp_common uvcvideo v4l2_vp9 snd_sof_xtensa_dsp v4l2_h264 mtk_vcodec= _dbgfs > snd_sof_of snd_sof ecdh_generic mtk_vcodec_common ecc uvc elan_i2c > videobuf2_vmalloc crct10dif_ce cros_ec_lid_angle cros_ec_sensors snd_sof_= utils > cros_ec_sensors_core cros_usbpd_logger cros_usbpd_charger fuse ip_tables = ipv6 > [ 93.376652] CPU: 5 PID: 3210 Comm: h265parse0:sink Tainted: G W= =20 > 6.8.0-rc4-next-20240212+ #14 > [ 93.386463] Hardware name: Acer Tomato (rev3 - 4) board (DT) > [ 93.392107] pstate: 80400009 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYP= E=3D--) > [ 93.399054] pc : vcodec_vpu_send_msg+0x4c/0x190 [mtk_vcodec_dec] > [ 93.405058] lr : vcodec_send_ap_ipi+0x78/0x170 [mtk_vcodec_dec] > [ 93.410968] sp : ffff80008750bc20 > [ 93.414269] x29: ffff80008750bc20 x28: ffff1299f6d70000 x27: 000000000= 0000000 > [ 93.421391] x26: 0000000000000000 x25: 0000000000000000 x24: 000000000= 0000000 > [ 93.428512] x23: ffff80008750bc98 x22: 000000000000a003 x21: ffffd45c4= cfae000 > [ 93.435632] x20: 0000000000000010 x19: ffff1299fd668310 x18: 000000000= 000001a > [ 93.442753] x17: 000000040044ffff x16: ffffd45cb15dc648 x15: 000000000= 0000000 > [ 93.449874] x14: ffff1299c08da1c0 x13: ffffd45cb1f87a10 x12: ffffd45cb= 2f5fe80 > [ 93.456995] x11: 0000000000000001 x10: 0000000000001b30 x9 : ffffd45c4= d12b488 > [ 93.464116] x8 : 1fffe25339380d81 x7 : 0000000000000001 x6 : ffff1299c= 9c06c00 > [ 93.471236] x5 : 0000000000000132 x4 : 0000000000000000 x3 : 000000000= 0000000 > [ 93.478358] x2 : 0000000000000010 x1 : ffff80008750bc98 x0 : 000000000= 0000000 > [ 93.485479] Call trace: > [ 93.487914] vcodec_vpu_send_msg+0x4c/0x190 [mtk_vcodec_dec] > [ 93.493563] vcodec_send_ap_ipi+0x78/0x170 [mtk_vcodec_dec] > [ 93.499125] vpu_dec_deinit+0x1c/0x30 [mtk_vcodec_dec] > [ 93.504254] vdec_hevc_slice_deinit+0x30/0x98 [mtk_vcodec_dec] > [ 93.510076] vdec_if_deinit+0x38/0x68 [mtk_vcodec_dec] > [ 93.515205] mtk_vcodec_dec_release+0x20/0x40 [mtk_vcodec_dec] > [ 93.521027] fops_vcodec_release+0x64/0x118 [mtk_vcodec_dec] > [ 93.526677] v4l2_release+0x7c/0x100 > [ 93.530245] __fput+0x80/0x2d8 > [ 93.533292] __fput_sync+0x58/0x70 > [ 93.536681] __arm64_sys_close+0x40/0x90 > [ 93.540590] invoke_syscall+0x50/0x128 > [ 93.544329] el0_svc_common.constprop.0+0x48/0xf0 > [ 93.549020] do_el0_svc+0x24/0x38 > [ 93.552323] el0_svc+0x38/0xd8 > [ 93.555367] el0t_64_sync_handler+0xc0/0xc8 > [ 93.559537] el0t_64_sync+0x1a8/0x1b0 > [ 93.563189] Code: d503201f f9401660 b900127f b900227f (f9400400)=20 > [ 93.569268] ---[ end trace 0000000000000000 ]--- >=20