In the Linux kernel, the following vulnerability has been resolved: s390/syscalls: Add spectre boundary for syscall dispatch table The s390 syscall number is directly controlled by userspace, but does not have an array_index_nospec() boundary to prevent access past the syscall function pointer tables.
https://git.kernel.org/stable/c/f8c444b918d639e1f9a621ee20fe481c1d10dfc4
https://git.kernel.org/stable/c/87776f02449e3bded95b2ccbd6b012e9ae64e6f3
https://git.kernel.org/stable/c/7a5260fbc6e79a1595328ec5c6aa3f937504a1f0
https://git.kernel.org/stable/c/4d05dd18d867d58c6952a3bc260d244899da7256
https://git.kernel.org/stable/c/48b8814e25d073dd84daf990a879a820bad2bcbd
https://git.kernel.org/stable/c/3c3b97064764899c39a0abbd35a6caa031e70333
https://git.kernel.org/stable/c/1cb9c7bc9025c637564fabc7fcc3c9343949e310