{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "0e2a9a03106cd5fa0dbc9047675e7645c55e2669"
            },
            {
              "fixed": "aa482273f32117c3adeba9b1cc945e0b5d33722d"
            },
            {
              "fixed": "8b8de6400c86937ed57d680d06d716e167b381de"
            },
            {
              "fixed": "e40b3edeaf25cd09e9c88edb1ef99373ca37593b"
            },
            {
              "fixed": "3690aaa6d18f6775c3e7932fb8af8c5bf6a6b69c"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.11.0"
            },
            {
              "fixed": "6.12.110"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.52"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90193.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nmailbox: qcom-cpucp: fix PREEMPT_RT self-deadlock in IRQ handler\n\nqcom_cpucp_mbox_irq_fn() calls mbox_chan_received_data() while holding\nchan-\u003elock. Under PREEMPT_RT, spin_lock_irqsave() is converted to an\nrt_spinlock (rtmutex-based), which tracks ownership and can sleep.\n\nThe callback chain triggered by mbox_chan_received_data() eventually\nreaches mailbox_clear_channel() -\u003e mbox_send_message() -\u003e add_to_rbuf(),\nwhich attempts to re-acquire the same chan-\u003elock. Since rtmutex detects\nthe re-entrant lock attempt by the same owner, the thread blocks waiting\nfor a lock it already holds, causing a permanent deadlock.\n\nThis deadlock manifests as 'irq/N-apss_cpucp_mbox' stuck in D state\nwith the following call trace:\n  rt_spin_lock -\u003e mbox_send_message -\u003e mailbox_clear_channel -\u003e\n  scmi_rx_callback -\u003e mbox_chan_received_data [\u003c- held chan-\u003elock here]\n\nFix by saving chan-\u003ecl locally and clearing the HW interrupt register\ninside the lock, then invoking mbox_chan_received_data() after releasing\nthe lock. This preserves the mutual exclusion for chan-\u003ecl access while\navoiding the lock re-entrancy that causes the PREEMPT_RT deadlock.",
  "id": "CVE-2026-90193",
  "modified": "2026-09-18T03:30:37.962837487Z",
  "published": "2026-09-17T16:07:13.672Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3690aaa6d18f6775c3e7932fb8af8c5bf6a6b69c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/8b8de6400c86937ed57d680d06d716e167b381de"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/aa482273f32117c3adeba9b1cc945e0b5d33722d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e40b3edeaf25cd09e9c88edb1ef99373ca37593b"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90193.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-90193"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "mailbox: qcom-cpucp: fix PREEMPT_RT self-deadlock in IRQ handler"
}