Hi, all There is bug with v5.4 aufs when doing following operations:
$mkdir a b c d $echo aaaaaa >a/a.txt $echo bbbbbb >b/b.txt $echo cccccc >c/c.txt $mount -v -t aufs -o br=/root/a:/root/b:/root/c none /root/d $cat /root/d/* Resulting in: [ 56.023644] kernel BUG at fs/aufs/finfo.c:114! [ 56.028761] Internal error: Oops - BUG: 0 [#1] SMP [ 56.033538] Modules linked in: xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xfrm_user xfrm_algo xt_addrtype iptable_filter ipt able_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 bpfilter br_netfilter bridge stp llc virt_wifi cfg80211 rfkill ip6table_filter ip6_ tables overlay nls_iso8859_1 vfat crct10dif_ce sbsa_gwdt arm_spe_pmu cppc_cpufreq sch_fq_codel ip_tables x_tables usbhid radeon i2c_algo_bit t tm hns3 drm_kms_helper hclge hisi_sas_v3_hw hnae3 drm hisi_sas_main libsas spi_dw_mmio spi_dw [ 56.078780] CPU: 9 PID: 1362 Comm: gvfs-udisks2-vo Not tainted 5.4.0+ #2 [ 56.085465] Hardware name: XXXX XXXX/Kunpeng Desktop Board D920L11K, BIOS 0.23 07/22/2020 [ 56.093627] pstate: 00000005 (nzcv daif -PAN -UAO) [ 56.098406] pc : au_finfo_fin+0x68/0x70 [ 56.102227] lr : au_finfo_fin+0x30/0x70 [ 56.106048] sp : ffffffa1e908bd00 [ 56.109348] x29: ffffffa1e908bd00 x28: ffffffa1e9080000 [ 56.114645] x27: 0000000000000000 x26: 0000000000000000 [ 56.119942] x25: ffffffa1ef738058 x24: ffffffa1f24c5480 [ 56.125239] x23: ffffffa1e91f4c00 x22: ffffffa1f01e3b80 [ 56.130536] x21: ffffffa1f2ea1000 x20: 0000000040000010 [ 56.135832] x19: ffffffa1e91f4c00 x18: 0000000000000000 [ 56.141129] x17: 0000000000000000 x16: 0000000000000000 [ 56.146426] x15: 0000000000000000 x14: 0000000000000000 [ 56.151723] x13: 0000000000000000 x12: 0000000000000000 [ 56.157019] x11: 0000000000000000 x10: 0000000000000000 [ 56.162316] x9 : 0000000000000000 x8 : 0000000000000000 [ 56.167613] x7 : ffffffa1e9080760 x6 : 0000000000000000 [ 56.172909] x5 : ffffffc0114370d8 x4 : 0000000000000000 [ 56.178205] x3 : 0000000000000000 x2 : ffffffe1eec90000 [ 56.183502] x1 : 0000000000000001 x0 : ffffffa1f2ea1000 [ 56.188798] Call trace: [ 56.191231] au_finfo_fin+0x68/0x70 [ 56.194706] aufs_release_dir+0x108/0x130 [ 56.198702] __fput+0xa4/0x230 [ 56.201742] ____fput+0xc/0x18 [ 56.204783] task_work_run+0xc8/0xf8 [ 56.208345] do_notify_resume+0x32c/0x380 [ 56.212340] work_pending+0x8/0x10 [ 56.215728] Code: f9400bf3 a8c27bfd d65f03c0 d4210000 (d4210000) Environment: Kernel: v5.4 Aufs: aufs5-standalone(5.4.3 20210104) Requirement: CONFIG_AUFS_DEBUG enabled BTW, this bug can reproduced with Ubuntu Focal if enable CONFIG_AUFS_DEBUG
