CVE-2026-90094

In the Linux kernel, the following vulnerability has been resolved:

arm64: process: Fix context switching MTE store-only tag check

SCTLR_EL1.TCSO0 is set when user opt-in for MTE store-only tag check mode. However, it is not part of SCTLR_USER_MASK which imply that on context switch we never clear SCTLR_EL1.TCSO0, so we are leaking that setting into another task.

Fix that by including SCTLR_EL1_TCSO0_MASK into SCTLR_USER_MASK