This is a note to let you know that I've just added the patch titled
KVM: SVM: Use unsigned integers when dealing with ASIDs
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
kvm-svm-use-unsigned-integers-when-dealing-with-asid.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e858aad3ddcaa8a3c512c65c11dd9f20117febaa
Author: Sean Christopherson <seanjc@xxxxxxxxxx>
Date: Wed Jan 31 15:56:07 2024 -0800
KVM: SVM: Use unsigned integers when dealing with ASIDs
[ Upstream commit 466eec4a22a76c462781bf6d45cb02cbedf21a61 ]
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.
Opportunistically use sev_get_asid() in sev_flush_encrypted_page() instead
of open coding an equivalent.
Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
Link: https://lore.kernel.org/r/20240131235609.4161407-3-seanjc@xxxxxxxxxx
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Stable-dep-of: 0aa6b90ef9d7 ("KVM: SVM: Add support for allowing zero SEV ASIDs")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index e86231c3b8a54..ea68a08cc89c2 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();
@@ -187,7 +189,7 @@ 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 */
@@ -2314,7 +2316,7 @@ 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 = sev_get_asid(vcpu->kvm);
/*
* Note! The address must be a kernel address, as regular page walk
@@ -2632,7 +2634,7 @@ 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 83843379813ee..b82e6ed4f0241 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)
);
