diff options
| -rw-r--r-- | arch/s390/kvm/pv.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/arch/s390/kvm/pv.c b/arch/s390/kvm/pv.c index c2dafd812a3b..4b865e75351c 100644 --- a/arch/s390/kvm/pv.c +++ b/arch/s390/kvm/pv.c @@ -17,6 +17,7 @@ #include <linux/pagewalk.h> #include <linux/sched/mm.h> #include <linux/mmu_notifier.h> +#include <asm/gmap_helpers.h> #include "kvm-s390.h" #include "dat.h" #include "gaccess.h" @@ -73,6 +74,7 @@ static bool should_export_before_import(struct uv_cb_header *uvcb, struct mm_str struct pv_make_secure { void *uvcb; struct folio *folio; + struct kvm *kvm; int rc; bool needs_export; }; @@ -103,9 +105,21 @@ static void _kvm_s390_pv_make_secure(struct guest_fault *f) { struct pv_make_secure *priv = f->priv; struct folio *folio; + spinlock_t *ptl; /* pte lock from try_get_locked_pte() */ + pte_t *ptep; folio = pfn_folio(f->pfn); priv->rc = -EAGAIN; + + if (!mmap_read_trylock(priv->kvm->mm)) + return; + + ptep = try_get_locked_pte(priv->kvm->mm, gfn_to_hva(priv->kvm, f->gfn), &ptl); + if (IS_ERR_VALUE(ptep)) { + priv->rc = PTR_ERR(ptep); + goto out; + } + if (folio_trylock(folio)) { priv->rc = __kvm_s390_pv_make_secure(f, folio); if (priv->rc == -E2BIG || priv->rc == -EBUSY) { @@ -114,6 +128,11 @@ static void _kvm_s390_pv_make_secure(struct guest_fault *f) } folio_unlock(folio); } + + if (ptep) + pte_unmap_unlock(ptep, ptl); +out: + mmap_read_unlock(priv->kvm->mm); } /** @@ -127,7 +146,7 @@ static void _kvm_s390_pv_make_secure(struct guest_fault *f) */ int kvm_s390_pv_make_secure(struct kvm *kvm, unsigned long gaddr, void *uvcb) { - struct pv_make_secure priv = { .uvcb = uvcb }; + struct pv_make_secure priv = { .uvcb = uvcb, .kvm = kvm, }; struct guest_fault f = { .write_attempt = true, .gfn = gpa_to_gfn(gaddr), |