Re: [PATCH v1] KVM: s390: GISA: sort out physical vs virtual pointers usage

[Michael Mueller <mimu@linux.ibm.com>]

Am 07.11.22 um 09:57 schrieb Nico Boehr:
> Fix virtual vs physical address confusion (which currently are the same).
> 
> In chsc_sgib(), do the virtual-physical conversion in the caller since
> the caller needs to make sure it is a 31-bit address and zero has a
> special meaning (disassociating the GIB).
> 
> Signed-off-by: Nico Boehr <nrb@linux.ibm.com>


Looks good to me!

Reviewed-by: Michael Mueller <mimu@linux.ibm.com>

> ---
>   arch/s390/kvm/interrupt.c | 11 +++++++----
>   1 file changed, 7 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
> index ab569faf0df2..ae018217eac8 100644
> --- a/arch/s390/kvm/interrupt.c
> +++ b/arch/s390/kvm/interrupt.c
> @@ -3104,9 +3104,9 @@ static enum hrtimer_restart gisa_vcpu_kicker(struct hrtimer *timer)
>   static void process_gib_alert_list(void)
>   {
>   	struct kvm_s390_gisa_interrupt *gi;
> +	u32 final, gisa_phys, origin = 0UL;
>   	struct kvm_s390_gisa *gisa;
>   	struct kvm *kvm;
> -	u32 final, origin = 0UL;
>   
>   	do {
>   		/*
> @@ -3132,9 +3132,10 @@ static void process_gib_alert_list(void)
>   		 * interruptions asap.
>   		 */
>   		while (origin & GISA_ADDR_MASK) {
> -			gisa = (struct kvm_s390_gisa *)(u64)origin;
> +			gisa_phys = origin;
> +			gisa = phys_to_virt(gisa_phys);
>   			origin = gisa->next_alert;
> -			gisa->next_alert = (u32)(u64)gisa;
> +			gisa->next_alert = gisa_phys;
>   			kvm = container_of(gisa, struct sie_page2, gisa)->kvm;
>   			gi = &kvm->arch.gisa_int;
>   			if (hrtimer_active(&gi->timer))
> @@ -3418,6 +3419,7 @@ void kvm_s390_gib_destroy(void)
>   
>   int kvm_s390_gib_init(u8 nisc)
>   {
> +	u32 gib_origin;
>   	int rc = 0;
>   
>   	if (!css_general_characteristics.aiv) {
> @@ -3439,7 +3441,8 @@ int kvm_s390_gib_init(u8 nisc)
>   	}
>   
>   	gib->nisc = nisc;
> -	if (chsc_sgib((u32)(u64)gib)) {
> +	gib_origin = virt_to_phys(gib);
> +	if (chsc_sgib(gib_origin)) {
>   		pr_err("Associating the GIB with the AIV facility failed\n");
>   		free_page((unsigned long)gib);
>   		gib = NULL;