Hello folks, I am currently developing a V4L2 driver with support on GStreamer, for that purpose I am mounting the GStreamer repository via NFS from my development machine to the target ARM64 hardware. I just switched to the latest kernel and got a sudden hang up of my system. What I did was a rebase of the GStreamer repository and then I wanted to build it with ninja on the target, this failed with a segmentation fault: ``` gstreamer| Configuring libgstreamer-1.0.so.0.2100.0-gdb.py using configurat= ion Segmentation fault FAILED: build.ninja=20 /usr/local/bin/meson --internal regenerate /home/user/gstreamer_crossbuild = /home/user/gstreamer_crossbuild/build --backend ninja ninja: error: rebuilding 'build.ninja': subcommand FAILED ``` And on the kernel side I got a OOPS: ``` [ 4595.193433] Unable to handle kernel NULL pointer dereference at virtual = address 0000000000000008 [ 4595.194259] Mem abort info: [ 4595.194518] ESR =3D 0x96000006 [ 4595.194857] EC =3D 0x25: DABT (current EL), IL =3D 32 bits [ 4595.195343] SET =3D 0, FnV =3D 0 [ 4595.195622] EA =3D 0, S1PTW =3D 0 [ 4595.195908] FSC =3D 0x06: level 2 translation fault [ 4595.196348] Data abort info: [ 4595.196610] ISV =3D 0, ISS =3D 0x00000006 [ 4595.196958] CM =3D 0, WnR =3D 0 [ 4595.197229] user pgtable: 4k pages, 48-bit VAs, pgdp=3D000000000450a000 [ 4595.197807] [0000000000000008] pgd=3D08000000f1812003, p4d=3D08000000f18= 12003, pud=3D08000000390bf003, pmd=3D0000000000000000 [ 4595.198793] Internal error: Oops: 96000006 [#1] PREEMPT SMP [ 4595.199300] Modules linked in: rpcsec_gss_krb5 auth_rpcgss nfsv4 nfs loc= kd grace fscache netfs iptable_nat nf_nat iptable_mangle bpfilter iptable_f= ilter btsdio ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_tcpudp= xt_state xt_conntrack nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nft_compa= t nf_tables nfnetlink hantro_vpu(C) rockchip_vdec(C) hci_uart v4l2_vp9 rock= chip_rga v4l2_h264 btqca videobuf2_dma_contig brcmfmac videobuf2_dma_sg v4l= 2_mem2mem btrtl snd_soc_es8316 snd_soc_audio_graph_card videobuf2_memops bt= bcm snd_soc_hdmi_codec snd_soc_simple_card snd_soc_rockchip_i2s snd_soc_spd= if_tx brcmutil videobuf2_v4l2 snd_soc_simple_card_utils btintel videobuf2_c= ommon snd_soc_core bluetooth cfg80211 snd_pcm_dmaengine videodev snd_pcm sn= d_timer dw_hdmi_i2s_audio mc dw_hdmi_cec snd rfkill soundcore cpufreq_dt su= nrpc ip_tables x_tables autofs4 cls_cgroup panfrost drm_shmem_helper gpu_sc= hed rockchipdrm drm_cma_helper dw_hdmi dw_mipi_dsi analogix_dp drm_dp_helpe= r drm_kms_helper cec rc_core [ 4595.199702] drm drm_panel_orientation_quirks realtek(E) [ 4595.207759] CPU: 4 PID: 3716 Comm: meson Tainted: G C E 5.1= 8.0-rc1-rockpidebug2 #94 [ 4595.208532] Hardware name: Radxa ROCK Pi 4B (DT) [ 4595.208938] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE= =3D--) [ 4595.209552] pc : list_lru_add+0xd4/0x180 [ 4595.209907] lr : list_lru_add+0x15c/0x180 [ 4595.210263] sp : ffff80000b75bbf0 [ 4595.210556] x29: ffff80000b75bbf0 x28: ffff000005cd9d80 x27: ffff0000056= 92a10 [ 4595.211188] x26: 00000000000000f0 x25: ffff000001962000 x24: ffff8000018= d7a80 [ 4595.211819] x23: 0000000000000000 x22: 0000000000000000 x21: 00000000000= 00000 [ 4595.212449] x20: ffff0000078fdc80 x19: ffff000013be8808 x18: 00000000000= 000c0 [ 4595.213080] x17: 0000000000000020 x16: fffffc0001028608 x15: fffffc00010= 28600 [ 4595.213710] x14: 1600000000000000 x13: 0000000000000008 x12: ffff0000f77= df278 [ 4595.214339] x11: 0000000000000000 x10: ffff0000f77df258 x9 : ffff8000088= 1f12c [ 4595.214970] x8 : ffff000001bbd300 x7 : 00000000ecc07b31 x6 : 00000000000= 00001 [ 4595.215600] x5 : ffff000001f04100 x4 : ffff80000b75bbb0 x3 : 00000000000= 00000 [ 4595.216229] x2 : 0000000000000001 x1 : 0000000000000000 x0 : 00000000000= 00000 [ 4595.216858] Call trace: [ 4595.217077] list_lru_add+0xd4/0x180 [ 4595.217396] nfs4_xattr_get_cache+0x254/0x368 [nfsv4] [ 4595.217910] nfs4_xattr_cache_set_list+0x2c/0x138 [nfsv4] [ 4595.218440] nfs4_listxattr+0x208/0x228 [nfsv4] [ 4595.218895] vfs_listxattr+0x60/0xb0 [ 4595.219215] listxattr+0x64/0x170 [ 4595.219510] path_listxattr+0x70/0xc8 [ 4595.219835] __arm64_sys_listxattr+0x28/0x38 [ 4595.220212] invoke_syscall+0x4c/0x110 [ 4595.220547] el0_svc_common.constprop.0+0x4c/0xf8 [ 4595.220963] do_el0_svc+0x2c/0x90 [ 4595.221257] el0_svc+0x2c/0x88 [ 4595.221532] el0t_64_sync_handler+0xb0/0xb8 [ 4595.221900] el0t_64_sync+0x18c/0x190 [ 4595.222227] Code: f9400317 8b1602f6 910022d7 aa1703e1 (f94006e0)=20 [ 4595.222763] ---[ end trace 0000000000000000 ]--- [ 4595.223179] note: meson[3716] exited with preempt_count 2 ``` I tried to get more information from the address information of the dump but sadly without success: ``` $ ./scripts/faddr2line fs/nfs/nfsv4.ko nfs4_xattr_get_cache+0x254/0x368=20 nfs4_xattr_get_cache+0x254/0x368: addr2line: DWARF error: info pointer extends beyond end of attributes addr2line: DWARF error: info pointer extends beyond end of attributes addr2line: DWARF error: info pointer extends beyond end of attributes addr2line: DWARF error: info pointer extends beyond end of attributes addr2line: DWARF error: info pointer extends beyond end of attributes addr2line: DWARF error: offset (2704378094) greater than or equal to .debug= _str size (1786) addr2line: DWARF error: info pointer extends beyond end of attributes addr2line: DWARF error: info pointer extends beyond end of attributes addr2line: DWARF error: info pointer extends beyond end of attributes addr2line: DWARF error: info pointer extends beyond end of attributes addr2line: DWARF error: offset (1670626809) greater than or equal to .debug= _line size (450319) nfs4_xattr_get_cache at nfs42xattr.c:? ``` (I probably did something wrong here :/) I was still able to attempt a reboot, but the system hanged itself then in an endless loop of interrupting self detected stalls and trying to unmount the NFS directory: https://paste.debian.net/1236971/ Thanks in advance :) Greetings, Sebastian
