On Fri, Jan 5, 2024 at 8:13 PM Sean Christopherson <seanjc@xxxxxxxxxx> wrote: > > Start by introducing such a new Kconfig symbol, CONFIG_KVM_COMMON. > > Unlike CONFIG_HAVE_KVM, it is selected by CONFIG_KVM, not by > > architecture code. > > Why? I don't get it, just have code that cares do IS_ENABLED(CONFIG_KVM). Except > for the MIPS usage of HAVE_KVM that you solved by adding CPU_SUPPORTS_VZ, I got > all the way there using just CONFIG_KVM[*]. > > Ah, and so does this series for the most part, the only usage of CONFIG_KVM_COMMON > is in scripts/gdb/linux/constants.py.in. Honestly, adding a Kconfig just so that > VMX's posted interrupts that arrive in the host can be printed when KVM is built > as a module is a waste of a Kconfig. There is one extra thing that CONFIG_KVM_COMMON does, which is to avoid having to select common requirements in all architectures. I jotted this to solve the reported randconfig failure, which is why CONFIG_KVM_COMMON only requires "select EVENTFD", but looking more closely it should also select PREEMPT_NOTIFIERS and INTERVAL_TREE. Both are used by virt/kvm/kvm_main.c, and loongarch + riscv both lack INTERVAL_TREE so I do think it's a good idea to introduce this symbol (though it requires a v2). > [*] https://lore.kernel.org/all/20230916003118.2540661-12-seanjc@xxxxxxxxxx I guess you mean https://lore.kernel.org/all/20230916003118.2540661-8-seanjc@xxxxxxxxxx/. Paolo
