From 80675b3ad45f79d97ce47a0faac3a6d22ab7e876 Mon Sep 17 00:00:00 2001 From: Tom Lendacky Date: Thu, 10 Dec 2020 11:10:05 -0600 Subject: [PATCH] KVM: SVM: Update ASID allocation to support SEV-ES guests SEV and SEV-ES guests each have dedicated ASID ranges. Update the ASID allocation routine to return an ASID in the respective range. Signed-off-by: Tom Lendacky Message-Id: Signed-off-by: Paolo Bonzini --- arch/x86/kvm/svm/sev.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 0e92274..b81d12f 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -61,19 +61,19 @@ static int sev_flush_asids(void) } /* Must be called with the sev_bitmap_lock held */ -static bool __sev_recycle_asids(void) +static bool __sev_recycle_asids(int min_asid, int max_asid) { int pos; /* Check if there are any ASIDs to reclaim before performing a flush */ - pos = find_next_bit(sev_reclaim_asid_bitmap, - max_sev_asid, min_sev_asid - 1); - if (pos >= max_sev_asid) + pos = find_next_bit(sev_reclaim_asid_bitmap, max_sev_asid, min_asid); + if (pos >= max_asid) return false; if (sev_flush_asids()) return false; + /* The flush process will flush all reclaimable SEV and SEV-ES ASIDs */ bitmap_xor(sev_asid_bitmap, sev_asid_bitmap, sev_reclaim_asid_bitmap, max_sev_asid); bitmap_zero(sev_reclaim_asid_bitmap, max_sev_asid); @@ -81,20 +81,23 @@ static bool __sev_recycle_asids(void) return true; } -static int sev_asid_new(void) +static int sev_asid_new(struct kvm_sev_info *sev) { + int pos, min_asid, max_asid; bool retry = true; - int pos; mutex_lock(&sev_bitmap_lock); /* - * SEV-enabled guest must use asid from min_sev_asid to max_sev_asid. + * SEV-enabled guests must use asid from min_sev_asid to max_sev_asid. + * SEV-ES-enabled guest can use from 1 to min_sev_asid - 1. */ + min_asid = sev->es_active ? 0 : min_sev_asid - 1; + max_asid = sev->es_active ? min_sev_asid - 1 : max_sev_asid; again: - pos = find_next_zero_bit(sev_asid_bitmap, max_sev_asid, min_sev_asid - 1); - if (pos >= max_sev_asid) { - if (retry && __sev_recycle_asids()) { + pos = find_next_zero_bit(sev_asid_bitmap, max_sev_asid, min_asid); + if (pos >= max_asid) { + if (retry && __sev_recycle_asids(min_asid, max_asid)) { retry = false; goto again; } @@ -176,7 +179,7 @@ static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) if (unlikely(sev->active)) return ret; - asid = sev_asid_new(); + asid = sev_asid_new(sev); if (asid < 0) return ret; -- 2.7.4