Public issue detail

Runaway CPU investigation for sshd-auth: timer churn at __schedule

sshd-auth is stuck in a likely timer churn loop: 36.29% of sampled CPU passed through __schedule, with repeated thread backtraces show 1 thread(s) around 0x00007fac7249a7d2 in ?? () from target:<path>.

highpackage: openssh-serversource: opensshscore: 106reports: 1

Last seen: 2026-06-08 23:10 UTC. Public JSON: /v1/issues/019ea8c5-24b9-7863-b730-83081994767c

Technical snapshot

This is the clearest retained userspace thread cluster Fixer captured while the process was spinning.

Representative thread backtrace

  • Command: sshd-auth: root [net]
  • Why Fixer classified it this way: Timer-related syscalls or symbols dominate the sample, which suggests a wakeup timer is firing too aggressively.
  • Thread summary: thread backtraces show 1 thread(s) around 0x00007fac7249a7d2 in ?? () from target:<path>
  • Contention signals: gdb-stderr: gdb: warning: Couldn't determine a path for the index cache directory.
  • Repeated loop: clock_nanosleep -> write -> write
  • Top syscalls: read x3, write x3, clock_nanosleep x1
  • Package: openssh-server 1:10.3p1-1
  • Kernel: 6.17.10+deb14-amd64
  • Distribution: debian
0x00007fac7249a7d2 in ?? () from target:<path>
0x00007fac7249a7ed in ?? () from target:<path>
0x00007fac725102d6 in read () from target:<path>
0x0000555ac9094eb3 in ?? ()
0x0000555ac905145f in ?? ()
0x0000555ac90516a3 in ?? ()
0x0000555ac90533a1 in ?? ()
0x0000555ac9048fe1 in ?? ()

Possible duplicates

These are suggestions based on sanitized trigram similarity plus structured fields like package, subsystem, classification, and wait site. They are not auto-merged.

Runaway CPU investigation for sshd-auth: timer churn at apparmor_socket_recvmsg

possible duplicate

sshd-auth is stuck in a likely timer churn loop: 100.00% of sampled CPU passed through apparmor_socket_recvmsg, with repeated thread backtraces show 1 thread(s) around 0x00007fa460a9a7d2 in ?? () from target:<path>.

highpackage: openssh-serversource: opensshscore: 106reports: 2patch attempt readysimilarity: 99%

Why this looks related: same classification, same package, same source package, same subsystem, same target, same wait site

Last seen: 2026-06-10 03:32 UTC. Public page: /issues/019dfcf9-7385-7c01-ba59-9fce98cd0a8f. Public JSON: /v1/issues/019dfcf9-7385-7c01-ba59-9fce98cd0a8f

Runaway CPU investigation for sshd-auth: timer churn at vfs_write

possible duplicate

sshd-auth is stuck in a likely timer churn loop: 100.00% of sampled CPU passed through vfs_write, with repeated thread backtraces show 1 thread(s) around 0x00007f76d5c9a7d2 in ?? () from target:<path>.

highpackage: openssh-serversource: opensshscore: 106reports: 2patch attempt readysimilarity: 99%

Why this looks related: same classification, same package, same source package, same subsystem, same target, same wait site, very similar public summary

Last seen: 2026-06-10 03:32 UTC. Public page: /issues/019e2c59-6707-7471-b7b2-5329d3cdd34e. Public JSON: /v1/issues/019e2c59-6707-7471-b7b2-5329d3cdd34e

Runaway CPU investigation for sshd-auth: timer churn at tcp_push

possible duplicate

sshd-auth is stuck in a likely timer churn loop: 100.00% of sampled CPU passed through tcp_push, with repeated thread backtraces show 1 thread(s) around 0x00007f51dfe9a7d2 in ?? () from target:<path>.

highpackage: openssh-serversource: opensshscore: 106reports: 1similarity: 99%

Why this looks related: same classification, same package, same source package, same subsystem, same target, same wait site, very similar public summary

Last seen: 2026-06-08 19:13 UTC. Public page: /issues/019ea31a-f962-7293-a0ce-bff12d2d13fa. Public JSON: /v1/issues/019ea31a-f962-7293-a0ce-bff12d2d13fa

Runaway CPU investigation for sshd-auth: busy poll at syscall_return_via_sysret

possible duplicate

sshd-auth is stuck in a likely busy poll loop: 50.00% of sampled CPU passed through syscall_return_via_sysret, with repeated read x3, write x2, clock_nanosleep x1.

highpackage: openssh-serversource: opensshscore: 106reports: 2similarity: 80%

Why this looks related: same package, same source package, same subsystem, same target, same wait site

Last seen: 2026-06-05 16:57 UTC. Public page: /issues/019e3ec4-e457-7410-8e2a-b04690dc6937. Public JSON: /v1/issues/019e3ec4-e457-7410-8e2a-b04690dc6937

Runaway CPU investigation for sshd-auth: busy poll at unresolved offset in sshd-auth

possible duplicate

sshd-auth is stuck in a likely busy poll loop: 100.00% of sampled CPU passed through unresolved offset, with repeated read x3, write x2, clock_nanosleep x1.

highpackage: openssh-serversource: opensshscore: 106reports: 2patch attempt readysimilarity: 78%

Why this looks related: same package, same source package, same subsystem, same target, same wait site

Last seen: 2026-06-10 03:32 UTC. Public page: /issues/019e1519-78c6-7813-bebb-aeb6177e1897. Public JSON: /v1/issues/019e1519-78c6-7813-bebb-aeb6177e1897

Runaway CPU investigation for sshd-auth: busy poll at default_wake_function

possible duplicate

sshd-auth is stuck in a likely busy poll loop: 50.00% of sampled CPU passed through default_wake_function, with repeated read x3, write x2, clock_nanosleep x1.

highpackage: openssh-serversource: opensshscore: 106reports: 1similarity: 77%

Why this looks related: same package, same source package, same subsystem, same target, same wait site

Last seen: 2026-06-10 01:46 UTC. Public page: /issues/019eacc4-cbcf-7c52-be3d-4fd249ca28e9. Public JSON: /v1/issues/019eacc4-cbcf-7c52-be3d-4fd249ca28e9

Published attempts

No public attempts have been published for this issue yet.

Quarantine stays on by default so the public queue is harder to spam.