On Mon, Apr 22, 2024, Song Liu wrote: > SPECULATION_MITIGATIONS is currently defined only for x86. As a result, > IS_ENABLED(CONFIG_SPECULATION_MITIGATIONS) is always false for other > archs. f337a6a21e2f effectively set "mitigations=off" by default on > non-x86 archs, which is not desired behavior. Jakub observed this > change when running bpf selftests on s390 and arm64. > > Fix this by moving SPECULATION_MITIGATIONS to arch/Kconfig so that it is > available in all archs and thus can be used safely in kernel/cpu.c Yeah, it's a known issue that we've been slow to fix because we've haven't come to an agreement on exactly what the Kconfig should look like[1], though there's general consensus to add CPU_MITIGATIONS in common code[2][3]. I'll poke Josh's thread and make sure a fix gets into rc6. [1] https://lore.kernel.org/all/20240417001507.2264512-2-seanjc@xxxxxxxxxx [2] https://lore.kernel.org/all/20240420000556.2645001-2-seanjc@xxxxxxxxxx [3] https://lore.kernel.org/all/9d3c997264829d0e2b28718222724ae8f9e7d8b4.1713559768.git.jpoimboe@xxxxxxxxxx
