Description
In the Linux kernel, the following vulnerability has been resolved: iommu/amd: move wait_on_sem() out of spinlock With iommu.strict=1, the existing completion wait path can cause soft lockups under stressed environment, as wait_on_sem() busy-waits under the spinlock with interrupts disabled. Move the completion wait in iommu_completion_wait() out of the spinlock. wait_on_sem() only polls the hardware-updated cmd_sem and does not require iommu->lock, so holding the lock during the busy wait unnecessarily increases contention and extends the time with interrupts disabled.
Affected products
linux: linux kernel
References6
- git.kernel.org/stable/c/496269d12072ecb219826485bdbec70c92a8eef5 Patch
- git.kernel.org/stable/c/715c263119fd1b918a9fcbd8a36ea5b604a46324 Patch
- git.kernel.org/stable/c/d2a0cac10597068567d336e85fa3cbdbe8ca62bf Patch
- git.kernel.org/stable/c/e15768e68820142077bbca402d8e902f64ade1b0 Patch
- git.kernel.org/stable/c/f2f65b28d802a667119147444ec2ae33eebf9a58 Patch
- git.kernel.org/stable/c/69d9339c02eddfc2a345be7220651068a3684383
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 31 · as of 13 November 2026
- CWE
- CWE-667CWE-833
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