4.9-stable review patch. If anyone has any objections, please let me know.
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From: Janosch Frank frankja@linux.vnet.ibm.com
commit ca76ec9ca871e67d8cd0b6caba24aca3d3ac4546 upstream.
All skey functions call skey_check_enable at their start, which checks if we are in the PSTATE and injects a privileged operation exception if we are.
Unfortunately they continue processing afterwards and perform the operation anyhow as skey_check_enable does not deliver an error if the exception injection was successful.
Let's move the PSTATE check into the skey functions and exit them on such an occasion, also we now do not enable skey handling anymore in such a case.
Signed-off-by: Janosch Frank frankja@linux.vnet.ibm.com Reviewed-by: Christian Borntraeger borntraeger@de.ibm.com Fixes: a7e19ab ("KVM: s390: handle missing storage-key facility") Reviewed-by: Cornelia Huck cohuck@redhat.com Reviewed-by: Thomas Huth thuth@redhat.com Signed-off-by: Christian Borntraeger borntraeger@de.ibm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/s390/kvm/priv.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
--- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -197,8 +197,6 @@ static int try_handle_skey(struct kvm_vc VCPU_EVENT(vcpu, 4, "%s", "retrying storage key operation"); return -EAGAIN; } - if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE) - return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP); return 0; }
@@ -209,6 +207,9 @@ static int handle_iske(struct kvm_vcpu * int reg1, reg2; int rc;
+ if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE) + return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP); + rc = try_handle_skey(vcpu); if (rc) return rc != -EAGAIN ? rc : 0; @@ -238,6 +239,9 @@ static int handle_rrbe(struct kvm_vcpu * int reg1, reg2; int rc;
+ if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE) + return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP); + rc = try_handle_skey(vcpu); if (rc) return rc != -EAGAIN ? rc : 0; @@ -273,6 +277,9 @@ static int handle_sske(struct kvm_vcpu * int reg1, reg2; int rc;
+ if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE) + return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP); + rc = try_handle_skey(vcpu); if (rc) return rc != -EAGAIN ? rc : 0;