| Message ID | 20240131235609.4161407-3-seanjc@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add support for allowing zero SEV ASIDs | expand |
On 1/31/24 17:56, Sean Christopherson wrote: > Convert all local ASID variables and parameters throughout the SEV code > from signed integers to unsigned integers. As ASIDs are fundamentally > unsigned values, and the global min/max variables are appropriately > unsigned integers, too. > > Functionally, this is a glorified nop as KVM guarantees min_sev_asid is > non-zero, and no CPU supports -1u as the _only_ asid, i.e. the signed vs. > unsigned goof won't cause problems in practice. > > Signed-off-by: Sean Christopherson <seanjc@google.com> Just one minor comment below, but either way... Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com> > --- > arch/x86/kvm/svm/sev.c | 18 ++++++++++-------- > arch/x86/kvm/trace.h | 10 +++++----- > 2 files changed, 15 insertions(+), 13 deletions(-) > > diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c > index 7c000088bca6..04c4c14473fd 100644 > --- a/arch/x86/kvm/svm/sev.c > +++ b/arch/x86/kvm/svm/sev.c > @@ -84,9 +84,10 @@ struct enc_region { > }; > > /* Called with the sev_bitmap_lock held, or on shutdown */ > -static int sev_flush_asids(int min_asid, int max_asid) > +static int sev_flush_asids(unsigned int min_asid, unsigned int max_asid) > { > - int ret, asid, error = 0; > + int ret, error = 0; > + unsigned int asid; > > /* Check if there are any ASIDs to reclaim before performing a flush */ > asid = find_next_bit(sev_reclaim_asid_bitmap, nr_asids, min_asid); > @@ -116,7 +117,7 @@ static inline bool is_mirroring_enc_context(struct kvm *kvm) > } > > /* Must be called with the sev_bitmap_lock held */ > -static bool __sev_recycle_asids(int min_asid, int max_asid) > +static bool __sev_recycle_asids(unsigned int min_asid, unsigned int max_asid) > { > if (sev_flush_asids(min_asid, max_asid)) > return false; > @@ -143,8 +144,9 @@ static void sev_misc_cg_uncharge(struct kvm_sev_info *sev) > > static int sev_asid_new(struct kvm_sev_info *sev) > { > - int asid, min_asid, max_asid, ret; > + unsigned int asid, min_asid, max_asid; > bool retry = true; > + int ret; > > WARN_ON(sev->misc_cg); > sev->misc_cg = get_current_misc_cg(); > @@ -188,7 +190,7 @@ static int sev_asid_new(struct kvm_sev_info *sev) > return ret; > } > > -static int sev_get_asid(struct kvm *kvm) > +static unsigned int sev_get_asid(struct kvm *kvm) > { > struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; > > @@ -284,8 +286,8 @@ static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) > > static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error) > { > + unsigned int asid = sev_get_asid(kvm); > struct sev_data_activate activate; > - int asid = sev_get_asid(kvm); > int ret; > > /* activate ASID on the given handle */ > @@ -2312,7 +2314,7 @@ int sev_cpu_init(struct svm_cpu_data *sd) > */ > static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va) > { > - int asid = to_kvm_svm(vcpu->kvm)->sev_info.asid; > + unsigned int asid = to_kvm_svm(vcpu->kvm)->sev_info.asid; Since you're touching this, you could switch this to: unsigned int asid = sev_get_asid(vcpu->kvm); > > /* > * Note! The address must be a kernel address, as regular page walk > @@ -2630,7 +2632,7 @@ void sev_es_unmap_ghcb(struct vcpu_svm *svm) > void pre_sev_run(struct vcpu_svm *svm, int cpu) > { > struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu); > - int asid = sev_get_asid(svm->vcpu.kvm); > + unsigned int asid = sev_get_asid(svm->vcpu.kvm); > > /* Assign the asid allocated with this SEV guest */ > svm->asid = asid; > diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h > index 83843379813e..b82e6ed4f024 100644 > --- a/arch/x86/kvm/trace.h > +++ b/arch/x86/kvm/trace.h > @@ -732,13 +732,13 @@ TRACE_EVENT(kvm_nested_intr_vmexit, > * Tracepoint for nested #vmexit because of interrupt pending > */ > TRACE_EVENT(kvm_invlpga, > - TP_PROTO(__u64 rip, int asid, u64 address), > + TP_PROTO(__u64 rip, unsigned int asid, u64 address), > TP_ARGS(rip, asid, address), > > TP_STRUCT__entry( > - __field( __u64, rip ) > - __field( int, asid ) > - __field( __u64, address ) > + __field( __u64, rip ) > + __field( unsigned int, asid ) > + __field( __u64, address ) > ), > > TP_fast_assign( > @@ -747,7 +747,7 @@ TRACE_EVENT(kvm_invlpga, > __entry->address = address; > ), > > - TP_printk("rip: 0x%016llx asid: %d address: 0x%016llx", > + TP_printk("rip: 0x%016llx asid: %u address: 0x%016llx", > __entry->rip, __entry->asid, __entry->address) > ); >
On Thu, Feb 01, 2024, Tom Lendacky wrote: > On 1/31/24 17:56, Sean Christopherson wrote: > > @@ -2312,7 +2314,7 @@ int sev_cpu_init(struct svm_cpu_data *sd) > > */ > > static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va) > > { > > - int asid = to_kvm_svm(vcpu->kvm)->sev_info.asid; > > + unsigned int asid = to_kvm_svm(vcpu->kvm)->sev_info.asid; > > Since you're touching this, you could switch this to: > > unsigned int asid = sev_get_asid(vcpu->kvm); Ah, good call, will do when applying. Thanks!
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 7c000088bca6..04c4c14473fd 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -84,9 +84,10 @@ struct enc_region { }; /* Called with the sev_bitmap_lock held, or on shutdown */ -static int sev_flush_asids(int min_asid, int max_asid) +static int sev_flush_asids(unsigned int min_asid, unsigned int max_asid) { - int ret, asid, error = 0; + int ret, error = 0; + unsigned int asid; /* Check if there are any ASIDs to reclaim before performing a flush */ asid = find_next_bit(sev_reclaim_asid_bitmap, nr_asids, min_asid); @@ -116,7 +117,7 @@ static inline bool is_mirroring_enc_context(struct kvm *kvm) } /* Must be called with the sev_bitmap_lock held */ -static bool __sev_recycle_asids(int min_asid, int max_asid) +static bool __sev_recycle_asids(unsigned int min_asid, unsigned int max_asid) { if (sev_flush_asids(min_asid, max_asid)) return false; @@ -143,8 +144,9 @@ static void sev_misc_cg_uncharge(struct kvm_sev_info *sev) static int sev_asid_new(struct kvm_sev_info *sev) { - int asid, min_asid, max_asid, ret; + unsigned int asid, min_asid, max_asid; bool retry = true; + int ret; WARN_ON(sev->misc_cg); sev->misc_cg = get_current_misc_cg(); @@ -188,7 +190,7 @@ static int sev_asid_new(struct kvm_sev_info *sev) return ret; } -static int sev_get_asid(struct kvm *kvm) +static unsigned int sev_get_asid(struct kvm *kvm) { struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; @@ -284,8 +286,8 @@ static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error) { + unsigned int asid = sev_get_asid(kvm); struct sev_data_activate activate; - int asid = sev_get_asid(kvm); int ret; /* activate ASID on the given handle */ @@ -2312,7 +2314,7 @@ int sev_cpu_init(struct svm_cpu_data *sd) */ static void sev_flush_encrypted_page(struct kvm_vcpu *vcpu, void *va) { - int asid = to_kvm_svm(vcpu->kvm)->sev_info.asid; + unsigned int asid = to_kvm_svm(vcpu->kvm)->sev_info.asid; /* * Note! The address must be a kernel address, as regular page walk @@ -2630,7 +2632,7 @@ void sev_es_unmap_ghcb(struct vcpu_svm *svm) void pre_sev_run(struct vcpu_svm *svm, int cpu) { struct svm_cpu_data *sd = per_cpu_ptr(&svm_data, cpu); - int asid = sev_get_asid(svm->vcpu.kvm); + unsigned int asid = sev_get_asid(svm->vcpu.kvm); /* Assign the asid allocated with this SEV guest */ svm->asid = asid; diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h index 83843379813e..b82e6ed4f024 100644 --- a/arch/x86/kvm/trace.h +++ b/arch/x86/kvm/trace.h @@ -732,13 +732,13 @@ TRACE_EVENT(kvm_nested_intr_vmexit, * Tracepoint for nested #vmexit because of interrupt pending */ TRACE_EVENT(kvm_invlpga, - TP_PROTO(__u64 rip, int asid, u64 address), + TP_PROTO(__u64 rip, unsigned int asid, u64 address), TP_ARGS(rip, asid, address), TP_STRUCT__entry( - __field( __u64, rip ) - __field( int, asid ) - __field( __u64, address ) + __field( __u64, rip ) + __field( unsigned int, asid ) + __field( __u64, address ) ), TP_fast_assign( @@ -747,7 +747,7 @@ TRACE_EVENT(kvm_invlpga, __entry->address = address; ), - TP_printk("rip: 0x%016llx asid: %d address: 0x%016llx", + TP_printk("rip: 0x%016llx asid: %u address: 0x%016llx", __entry->rip, __entry->asid, __entry->address) );
Convert all local ASID variables and parameters throughout the SEV code from signed integers to unsigned integers. As ASIDs are fundamentally unsigned values, and the global min/max variables are appropriately unsigned integers, too. Functionally, this is a glorified nop as KVM guarantees min_sev_asid is non-zero, and no CPU supports -1u as the _only_ asid, i.e. the signed vs. unsigned goof won't cause problems in practice. Signed-off-by: Sean Christopherson <seanjc@google.com> --- arch/x86/kvm/svm/sev.c | 18 ++++++++++-------- arch/x86/kvm/trace.h | 10 +++++----- 2 files changed, 15 insertions(+), 13 deletions(-)