printk: Postpone kthread startup

Description

In the Linux kernel, the following vulnerability has been resolved: printk: Postpone kthread startup There have been various bug reports related to SMP systems hanging on boot. The reports vary but seem to have some overlap with regard to missed IPI's during SMP setup. The reports also show that reverting NBCON console usage allows the bugs to disappear. The NBCON kthreads for console printing are started very early during boot using early_initcall(). Since these kthreads are asynchronously enabling/disabling interrupts during early boot, they may be interfering with early SMP setup on some hardware platforms. Starting the console printing kthreads later has shown to avoid the hanging on systems that could previously reproduce the issue. Postpone kthread starting until after all arch initcalls have completed.

Scores

No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.

EPSS (exploitation in 30 days)

0.16% · top 95% of all CVEs (6 Nov 2026)

The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.

Affected products

• Linux · Linux

  • affected 76f258bf3f2aae570209319944703a92ac64e29e – < a86bcdd84c8fe7a45f73e12d53fe06fea07d1ceb
  • affected 76f258bf3f2aae570209319944703a92ac64e29e – < 7595bacee48bc30b5021eccf199d704d4e5e5374
  • affected 76f258bf3f2aae570209319944703a92ac64e29e – < 792acd173da0884f0172c68cb473f42cf93c647e
  • affected 76f258bf3f2aae570209319944703a92ac64e29e – < 5f339c46f153184570f16c8e789c9709b14cbe8b

• Linux · Linux

  • affected 6.12
  • unaffected < 6.12
  • unaffected 6.12.115 – ≤ 6.12.*
  • unaffected 6.18.59 – ≤ 6.18.*
  • unaffected 7.2.13 – ≤ 7.2.*
  • unaffected 7.3 – ≤ *

References (4)

• https://git.kernel.org/stable/c/a86bcdd84c8fe7a45f73e12d53fe06fea07d1ceb (opens in a new tab)
• https://git.kernel.org/stable/c/7595bacee48bc30b5021eccf199d704d4e5e5374 (opens in a new tab)
• https://git.kernel.org/stable/c/792acd173da0884f0172c68cb473f42cf93c647e (opens in a new tab)
• https://git.kernel.org/stable/c/5f339c46f153184570f16c8e789c9709b14cbe8b (opens in a new tab)

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-99250](https://trackcve.app/badge/CVE-2026-99250.svg)](https://trackcve.app/cve/CVE-2026-99250)

Record last updated 3 Nov 2026, 11:18 UTC.