Vulnerabilities

Vulnerability · CVE-2026-98473

In the Linux kernel, the following vulnerability has been resolved: s390/vfio-ap: fix KVM GISC and page leak when queue removed from host config Three related problems…

Published Oct 18, 2026 · catalog updated Oct 18, 2026 · the affected product

Open the advisory

Exploitation likelihood is not on this record for CVE-2026-98473. A missing EPSS score is not a low risk. Compare the affected product with the linked advisory before you change production.

Severity

Unknown—

Known exploitation

Not in CISA/VulnCheck KEV

EPSS

Awaiting synchronization with FIRST

Remediation

Not established

Affected products

See sources for product scope

In the Linux kernel, the following vulnerability has been resolved: s390/vfio-ap: fix KVM GISC and page leak when queue removed from host config Three related problems exist in the handling of KVM interrupt and page resources when a queue is removed from the host's AP configuration while assigned to a mediated device (mdev). Problem 1: ~~~~~~~~~ AP_RESPONSE_Q_NOT_AVAIL not handled in vfio_ap_mdev_reset_queue() When the AP bus removes a queue device whose adapter or domain has been removed from the host's AP configuration, vfio_ap_mdev_remove_queue() is called. If the queue is still in the host's AP configuration at that point, it calls vfio_ap_mdev_reset_queue(), which issues a PQAP(ZAPQ). Since the adapter is already gone from the host configuration, ap_zapq() returns AP_RESPONSE_Q_NOT_AVAIL (0x01). This response code is not handled in vfio_ap_mdev_reset_queue()'s switch statement and falls through to the default case, which issues a WARN but does not call vfio_ap_free_aqic_resources(). As a result, if IRQ handling was enabled for the queue by the guest, the KVM GISC registration and the pinned guest page holding the notification indicator byte (NIB) are both leaked. This is fixed by adding AP_RESPONSE_Q_NOT_AVAIL to the same case as AP_RESPONSE_DECONFIGURED and AP_RESPONSE_CHECKSTOPPED in vfio_ap_mdev_reset_queue(). Like those response codes, Q_NOT_AVAIL indicates the queue is not operational and no further reset attempts are possible; the correct action is to free the IRQ resources immediately. Problem 2: ~~~~~~~~~ AP_RESPONSE_Q_NOT_AVAIL not handled in apq_status_check() In vfio_ap_mdev_reset_queue(), there are four cases that indicate a queue reset has not yet completed, in which case apq_reset_check() is queued to a work queue to verify completion of the reset operation. This function uses the PQAP(TAPQ) function to get the queue's status and calls apq_status_check() to verify whether the reset has completed, failed or needs to be executed again. As described

No affected version ranges are stored yet. Use the vendor advisory before you decide this record does not apply.