On Thu, Feb 04, 2016 at 11:00:37AM +0000, Marc Zyngier wrote: > Having u64 as the kvm_call_hyp return type is problematic, as > it forces all kind of tricks for the return values from HYP > to be promoted to 64bit (LE has the LSB in r0, and BE has them > in r1). > > Since the only user of the return value is perfectly happy with > a 32bit value, let's make kvm_call_hyp return an unsigned long, > which is 32bit on ARM. I wonder why I ever did this as a u64... should the arm64 counterpart be modified to an unsigned long as well? > > This solves yet another headache. > > Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> > --- > arch/arm/include/asm/kvm_host.h | 2 +- > arch/arm/kvm/interrupts.S | 10 ++-------- > 2 files changed, 3 insertions(+), 9 deletions(-) > > diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h > index 02932ba..c62d717 100644 > --- a/arch/arm/include/asm/kvm_host.h > +++ b/arch/arm/include/asm/kvm_host.h > @@ -165,7 +165,7 @@ unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu); > int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices); > int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg); > int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg); > -u64 kvm_call_hyp(void *hypfn, ...); > +unsigned long kvm_call_hyp(void *hypfn, ...); > void force_vm_exit(const cpumask_t *mask); > > #define KVM_ARCH_WANT_MMU_NOTIFIER > diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S > index 7bfb289..01eb169 100644 > --- a/arch/arm/kvm/interrupts.S > +++ b/arch/arm/kvm/interrupts.S > @@ -207,20 +207,14 @@ after_vfp_restore: > > restore_host_regs > clrex @ Clear exclusive monitor > -#ifndef CONFIG_CPU_ENDIAN_BE8 > mov r0, r1 @ Return the return code > - mov r1, #0 @ Clear upper bits in return value > -#else > - @ r1 already has return code > - mov r0, #0 @ Clear upper bits in return value > -#endif /* CONFIG_CPU_ENDIAN_BE8 */ > bx lr @ return to IOCTL > > /******************************************************************** > * Call function in Hyp mode > * > * > - * u64 kvm_call_hyp(void *hypfn, ...); > + * unsigned long kvm_call_hyp(void *hypfn, ...); > * > * This is not really a variadic function in the classic C-way and care must > * be taken when calling this to ensure parameters are passed in registers > @@ -231,7 +225,7 @@ after_vfp_restore: > * passed as r0, r1, and r2 (a maximum of 3 arguments in addition to the > * function pointer can be passed). The function being called must be mapped > * in Hyp mode (see init_hyp_mode in arch/arm/kvm/arm.c). Return values are > - * passed in r0 and r1. > + * passed in r0 (strictly 32bit). > * > * A function pointer with a value of 0xffffffff has a special meaning, > * and is used to implement __hyp_get_vectors in the same way as in > -- > 2.1.4 > Reviewed-by: Christoffer Dall <christoffer.dall@xxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
