On 1/18/25 03:37, Rob Herring wrote: > On Thu, Jan 16, 2025 at 9:32 AM Catalin Marinas <catalin.marinas@xxxxxxx> wrote: >> >> On Wed, Jan 08, 2025 at 07:47:16AM -0600, Rob Herring wrote: >>> On Wed, Jan 8, 2025 at 5:15 AM Marc Zyngier <maz@xxxxxxxxxx> wrote: >>>> On Tue, 07 Jan 2025 22:13:47 +0000, >>>> Rob Herring <robh@xxxxxxxxxx> wrote: >>>>> On Tue, Jan 7, 2025 at 6:13 AM Catalin Marinas <catalin.marinas@xxxxxxx> wrote: >>>>>> But does KVM actually expose the feature to EL1 in ID_AA64DFR1_EL1 and >>>>>> than traps it at EL2? >>>>> >>>>> As Marc pointed out KVM only advertises PMUv3.8. Regardless, guest >>>>> accesses to these registers are trapped with or without this series. >>>> >>>> And most probably generates a nice splat in the kernel log, as nobody >>>> updated KVM to handle *correctly* PMICNTR_EL0 traps, let alone deal >>>> with the FGT2 registers. >>> >>> Isn't that this series[1]? Should that have come first, I guess I know >>> that *now*. >> [...] >>> [1] https://lore.kernel.org/all/20241210055311.780688-1-anshuman.khandual@xxxxxxx/ >> >> It's not any clearer to me. Does this series depend on the 46-patch one? >> Or, if we had the other, is this no longer needed? Or none of these, >> they are independent. > > They are independent. I think ideally we'd want everything landing at > the same time, but we're past ideal at this point. Without this > series, if someone uses PMU on v8.9 and firmware enabled FGT2, then > the kernel will crash. Without the above series, KVM will have > warnings in the kernel log, but otherwise function. Right, they are independent. Just that Rob had observed this PMU v3.8 boot requirement while reviewing the HW breakpoint series earlier. I should just respin this series after the upcoming v6.14-rc1 release is out ?
