Public bug reported: Issue description kcryptd freeze waiting for io for a dm-crypt (luks2) partition formatted with btrfs on top. The system has 4 cores.
Steps for reproducing the issue For me it happens randomly for 1 kernel thread, then after a while 3 others also freeze and the system is then dead. eg first after a few minutes with heavy io ps aux ... root 265 0.5 0.0 0 0 ? D 21:16 0:02 [kworker/u8:3+kcryptd/253:2] ... then a bit later root 265 0.1 0.0 0 0 ? D 21:16 0:02 [kworker/u8:3+kcryptd/253:2] root 310 0.1 0.0 0 0 ? D 21:16 0:02 [kworker/u8:8+kcryptd/253:2] root 312 0.2 0.0 0 0 ? D 21:16 0:03 [kworker/u8:10+btrfs-endio-write] root 313 0.1 0.0 0 0 ? D 21:16 0:02 [kworker/u8:11+btrfs-endio-write] root 314 0.1 0.0 0 0 ? D 21:16 0:01 [kworker/u8:12+flush-btrfs-2] root 315 0.1 0.0 0 0 ? D 21:16 0:02 [kworker/u8:13+kcryptd/253:2] root 1612 0.0 0.0 0 0 ? D 21:16 0:00 [btrfs-transacti] root 4133 0.0 0.0 0 0 ? D 21:22 0:00 [kworker/u8:0+kcryptd/253:2] root 4135 0.0 0.0 0 0 ? D 21:22 0:00 [kworker/u8:4+btrfs-endio-write] root 4137 0.0 0.0 0 0 ? D 21:22 0:00 [kworker/u8:14+btrfs-endio-write] root 4977 0.0 0.0 0 0 ? D 21:30 0:00 [kworker/u8:1+btrfs-endio-write] root 4978 0.0 0.0 0 0 ? D 21:30 0:00 [kworker/u8:2+btrfs-endio-write] Additional info Ubuntu focal install with btrfs on luks partitions. Kernel info Linux 5.4.0-31-generic #35-Ubuntu SMP x86_64 x86_64 x86_64 GNU/Linux lscpu Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian Address sizes: 39 bits physical, 48 bits virtual CPU(s): 4 On-line CPU(s) list: 0-3 Thread(s) per core: 1 Core(s) per socket: 4 Socket(s): 1 NUMA node(s): 1 Vendor ID: GenuineIntel CPU family: 6 Model: 95 Model name: Intel(R) Atom(TM) CPU C3558 @ 2.20GHz Stepping: 1 CPU MHz: 2200.413 CPU max MHz: 2200,0000 CPU min MHz: 800,0000 BogoMIPS: 4400.00 Virtualization: VT-x L1d cache: 96 KiB L1i cache: 128 KiB L2 cache: 8 MiB NUMA node0 CPU(s): 0-3 Vulnerability Itlb multihit: Not affected Vulnerability L1tf: Not affected Vulnerability Mds: Not affected Vulnerability Meltdown: Not affected Vulnerability Spec store bypass: Mitigation; Speculative Store Bypass disabled via prctl and seccomp Vulnerability Spectre v1: Mitigation; usercopy/swapgs barriers and __user pointer sanitization Vulnerability Spectre v2: Mitigation; Full generic retpoline, IBPB conditional, IBRS_FW, STIBP disabled, RSB filling Vulnerability Tsx async abort: Not affected Flags: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 sdbg cx16 xtpr pdcm sse4_1 sse4_2 x2apic movbe popcnt tsc_deadline_timer aes xsave rdrand lahf_lm 3dnowprefetch cpuid_fault epb cat_l2 ssbd ibrs ibpb stibp tpr_shadow vnmi flex priority ept vpid ept_ad fsgsbase tsc_adjust smep erms mpx rdt_a rdseed smap clflushopt intel_pt sha_ni xsaveopt xsavec xgetbv1 xsaves dtherm arat pln pts md_clea r arch_capabilities kernel crypto flags cat /boot/config-5.4.0-31-generic | grep AES CONFIG_CRYPTO_AEGIS128_AESNI_SSE2=m CONFIG_CRYPTO_LIB_AES=y CONFIG_CRYPTO_AES=y CONFIG_CRYPTO_AES_TI=m CONFIG_CRYPTO_AES_NI_INTEL=m CONFIG_CRYPTO_CAMELLIA_AESNI_AVX_X86_64=m CONFIG_CRYPTO_CAMELLIA_AESNI_AVX2_X86_64=m CONFIG_CRYPTO_DEV_PADLOCK_AES=m /etc/crypttab LUKS_DATA_6T_1 UUID=the_uuid /etc/....keyfile luks Related bug reports: https://gitlab.com/cryptsetup/cryptsetup/-/issues/568 -> rejected, referred to ubuntu kernel team. ** Affects: linux (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1922022 Title: Btrfs blocked io when running on top of luks encrypted partition To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1922022/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
