{"cve":"CVE-2026-93254","nvd":{"published":"2026-09-24T16:17:21.807","modified":"2026-10-19T10:17:16.687","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\narm64: entry: Avoid unnecessary local_irq_disable() on kernel exit\n\nCurrently, when exiting to kernel mode, we attempt involuntary\npreemption. The preemption logic expects IRQs to be disabled, which is\nwhy we call local_irq_disable() before attempting preemption.\n\nHowever, depending on the context, local_irq_disable() may be\nunnecessary:\n\n- __el1_irq(), the non-NMI EL1 IRQ path, already has IRQs disabled, so\n  local_irq_disable() is redundant.\n\n- irqentry_exit_to_kernel_mode_preempt() immediately returns when\n  exiting from an NMI-like context, so calling local_irq_disable()\n  beforehand is unnecessary work.\n\nFurthermore, it confuses the pNMI state tracking when we are in a\ncontext with interrupts disabled and the GIC_PRIO_PSR_I_SET bit is set\nin the PMR, leading to a warning when\nCONFIG_ARM64_DEBUG_PRIORITY_MASKING=y:\n\n     WARNING: ./arch/arm64/include/asm/irqflags.h:63 at arm64_exit_to_kernel_mode+0xb8/0xc0, CPU#40: retsnoop/31805\n     CPU: 40 UID: 0 PID: 31805 Comm: retsnoop Not tainted 7.2.0-rc6-next-20260805 #7 PREEMPTLAZY\n     pstate: 234013c9 (nzCv DAIF +PAN -UAO +TCO +DIT +SSBS BTYPE=--)\n     pc : arm64_exit_to_kernel_mode (arch/arm64/kernel/entry-common.c:63)\n     lr : el1_abort (arch/arm64/kernel/entry-common.c:323)\n     pmr: 000000f0\n     Call trace:\n      arm64_exit_to_kernel_mode (arch/arm64/kernel/entry-common.c:63) (P)\n      el1_abort (arch/arm64/kernel/entry-common.c:323)\n      el1h_64_sync_handler (arch/arm64/kernel/entry-common.c:449)\n      el1h_64_sync (arch/arm64/kernel/entry.S:589)\n      [...]\n\nSplit arm64_exit_to_kernel_mode() into preempt, non-preempt, and\ndispatch parts so that we can avoid this extra work where it is not\nneeded and avoid breaking the pNMI tracking logic.","cvss_v4":null,"cvss_v3":null,"cwes":[],"references":["https://git.kernel.org/stable/c/39aebe0e89469c2904e60b1e977e0d4dbf33326b","https://git.kernel.org/stable/c/49a61174186bed25d439ff37400c7ce5e3603e73"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:56:02.509636177+00:00"},"epss":{"cve":"CVE-2026-93254","score":0.0021,"percentile":0.11156,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}