On Thu, 11 Mar 2021 at 10:35, Quentin Perret <qperret@xxxxxxxxxx> wrote: > > On Thursday 04 Mar 2021 at 11:54:47 (+0000), 'Andrew Scull' via kernel-team wrote: > > smp_procesor_id() works off of the cpu_number per-cpu variable. Create > > an nVHE hyp version of cpu_number and initialize it to the same value as > > the host when creating the hyp per-cpu regions. > > > > Signed-off-by: Andrew Scull <ascull@xxxxxxxxxx> > > --- > > arch/arm64/kvm/arm.c | 2 ++ > > arch/arm64/kvm/hyp/nvhe/hyp-smp.c | 2 ++ > > 2 files changed, 4 insertions(+) > > > > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > > index 26ccc369cf11..e3edea8379f3 100644 > > --- a/arch/arm64/kvm/arm.c > > +++ b/arch/arm64/kvm/arm.c > > @@ -54,6 +54,7 @@ DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector); > > static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page); > > unsigned long kvm_arm_hyp_percpu_base[NR_CPUS]; > > DECLARE_KVM_NVHE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params); > > +DECLARE_KVM_NVHE_PER_CPU(int, cpu_number); > > > > /* The VMID used in the VTTBR */ > > static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1); > > @@ -1740,6 +1741,7 @@ static int init_hyp_mode(void) > > page_addr = page_address(page); > > memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size()); > > kvm_arm_hyp_percpu_base[cpu] = (unsigned long)page_addr; > > + *per_cpu_ptr_nvhe_sym(cpu_number, cpu) = cpu; > > } > > > > /* > > diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-smp.c b/arch/arm64/kvm/hyp/nvhe/hyp-smp.c > > index 879559057dee..86f952b1de18 100644 > > --- a/arch/arm64/kvm/hyp/nvhe/hyp-smp.c > > +++ b/arch/arm64/kvm/hyp/nvhe/hyp-smp.c > > @@ -8,6 +8,8 @@ > > #include <asm/kvm_hyp.h> > > #include <asm/kvm_mmu.h> > > > > +DEFINE_PER_CPU_READ_MOSTLY(int, cpu_number); > > Is smp_processor_id() going to work at EL2 with CONFIG_DEBUG_PREEMPT=y ? > If not, then maybe we should have out own hyp_smp_processor_id() macro? It's not, preempt_count() won't work,= at a minimum. I got far too drawn into the other branch of that #ifdef. We only use __smp_processor_id() in hyp, but that might not play too nicely with VHE and forgetting the leading underscores will just lead to nVHE issues that might not be caught in the build. So you might be right that this is a case where we need to break from standard APIs. And we can define `raw_smp_processor_id()` to something that will give a compile time error when used in hyp to try and prevent accidental misuse. _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
