From 174dd4f88875f6ebad7ad1dff3c3e9530a1e3506 Mon Sep 17 00:00:00 2001 From: Michael Mueller Date: Thu, 31 Jan 2019 09:52:43 +0100 Subject: KVM: s390: kvm_s390_gisa_clear() now clears the IPM only Function kvm_s390_gisa_clear() now clears the Interruption Pending Mask of the GISA asap. If the GISA is in the alert list at this time it stays in the list but is removed by process_gib_alert_list(). Signed-off-by: Michael Mueller Acked-by: Halil Pasic Reviewed-by: Pierre Morel Message-Id: <20190131085247.13826-13-mimu@linux.ibm.com> Signed-off-by: Christian Borntraeger --- arch/s390/kvm/interrupt.c | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) (limited to 'arch/s390') diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index 040745b232249..9faaa8f96fc34 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -249,6 +249,25 @@ static inline int gisa_set_iam(struct kvm_s390_gisa *gisa, u8 iam) return 0; } +/** + * gisa_clear_ipm - clear the GISA interruption pending mask + * + * @gisa: gisa to operate on + * + * Clear the IPM atomically with the next alert address and the IAM + * of the GISA unconditionally. All three fields are located in the + * first long word of the GISA. + */ +static inline void gisa_clear_ipm(struct kvm_s390_gisa *gisa) +{ + u64 word, _word; + + do { + word = READ_ONCE(gisa->u64.word[0]); + _word = word & ~(0xffUL << 24); + } while (cmpxchg(&gisa->u64.word[0], word, _word) != word); +} + static inline void gisa_set_ipm_gisc(struct kvm_s390_gisa *gisa, u32 gisc) { set_bit_inv(IPM_BIT_OFFSET + gisc, (unsigned long *) gisa); @@ -2926,8 +2945,7 @@ void kvm_s390_gisa_clear(struct kvm *kvm) if (!gi->origin) return; - memset(gi->origin, 0, sizeof(struct kvm_s390_gisa)); - gi->origin->next_alert = (u32)(u64)gi->origin; + gisa_clear_ipm(gi->origin); VM_EVENT(kvm, 3, "gisa 0x%pK cleared", gi->origin); } @@ -2940,7 +2958,8 @@ void kvm_s390_gisa_init(struct kvm *kvm) gi->origin = &kvm->arch.sie_page2->gisa; gi->alert.mask = 0; spin_lock_init(&gi->alert.ref_lock); - kvm_s390_gisa_clear(kvm); + memset(gi->origin, 0, sizeof(struct kvm_s390_gisa)); + gi->origin->next_alert = (u32)(u64)gi->origin; VM_EVENT(kvm, 3, "gisa 0x%pK initialized", gi->origin); } -- cgit v1.2.3