On Tue, Feb 19, 2019 at 02:54:30PM +0530, Amit Daniel Kachhap wrote: > According to userspace settings, ptrauth key registers are conditionally > present in guest system register list based on user specified flag > KVM_ARM_VCPU_PTRAUTH. > > Reset routines still sets these registers to default values but they are > left like that as they are conditionally accessible (set/get). > > Signed-off-by: Amit Daniel Kachhap <amit.kachhap at arm.com> > Cc: Mark Rutland <mark.rutland at arm.com> > Cc: Marc Zyngier <marc.zyngier at arm.com> > Cc: Christoffer Dall <christoffer.dall at arm.com> > Cc: kvmarm at lists.cs.columbia.edu > --- > This patch needs patch [1] by Dave Martin and adds feature to manage accessibility in a scalable way. > > [1]: https://lore.kernel.org/linux-arm-kernel/1547757219-19439-13-git-send-email-Dave.Martin at arm.com/ FYI, check_present() has changed a bit in the SVE v5 series [2]. The precise interface is still under discussion, so please take a look and feel free to comment. You'll probably need to tweak some things so that the KVM_GET_REG_LIST output is consistent with the set of regs that do/don't yield -ENOENT in KVM_GET_ONE_REG/KVM_SET_ONE_REG. See other patches in the series for examples of how I use the modified interface. [...] > diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c > index f7bcc60..c2f4974 100644 > --- a/arch/arm64/kvm/sys_regs.c > +++ b/arch/arm64/kvm/sys_regs.c > @@ -1005,8 +1005,13 @@ static bool trap_ptrauth(struct kvm_vcpu *vcpu, > return false; > } > > +static bool check_ptrauth(const struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd) > +{ > + return kvm_arm_vcpu_ptrauth_allowed(vcpu); > +} > + > #define __PTRAUTH_KEY(k) \ > - { SYS_DESC(SYS_## k), trap_ptrauth, reset_unknown, k } > + { SYS_DESC(SYS_## k), trap_ptrauth, reset_unknown, k , .check_present = check_ptrauth} Cheers ---Dave [2] [PATCH v5 12/26] KVM: arm64: Support runtime sysreg visibility filtering https://lists.cs.columbia.edu/pipermail/kvmarm/2019-February/034671.html
