qemu-kvm/kvm-target-s390x-kvm-Honor-storage-keys-during-emulation.patch

From 27c1d979a994f5afc59c3520af58d15aa5aae723 Mon Sep 17 00:00:00 2001
From: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Date: Fri, 6 May 2022 17:39:56 +0200
Subject: [PATCH 29/32] target/s390x: kvm: Honor storage keys during emulation

RH-Author: Thomas Huth <thuth@redhat.com>
RH-MergeRequest: 109: Honor storage keys during emulation of I/O instructions
RH-Commit: [2/2] 346dee1e13bfe1c074e4c6a4417091711d852f9c (thuth/qemu-kvm-cs9)
RH-Bugzilla: 2111994
RH-Acked-by: Cornelia Huck <cohuck@redhat.com>
RH-Acked-by: David Hildenbrand <david@redhat.com>
RH-Acked-by: Claudio Imbrenda <None>

Storage key controlled protection is currently not honored when
emulating instructions.
If available, enable key protection for the MEM_OP ioctl, thereby
enabling it for the s390_cpu_virt_mem_* functions, when using kvm.
As a result, the emulation of the following instructions honors storage
keys:

* CLP
  	The Synch I/O CLP command would need special handling in order
  	to support storage keys, but is currently not supported.
* CHSC
	Performing commands asynchronously would require special
	handling, but commands are currently always synchronous.
* STSI
* TSCH
	Must (and does) not change channel if terminated due to
	protection.
* MSCH
	Suppressed on protection, works because fetching instruction.
* SSCH
	Suppressed on protection, works because fetching instruction.
* STSCH
* STCRW
	Suppressed on protection, this works because no partial store is
	possible, because the operand cannot span multiple pages.
* PCISTB
* MPCIFC
* STPCIFC

Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Message-Id: <20220506153956.2217601-3-scgl@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

(cherry picked from commit 54354861d21b69ec0781f43e67b8d4f6edad7e3f)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2111994
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 target/s390x/kvm/kvm.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/target/s390x/kvm/kvm.c b/target/s390x/kvm/kvm.c
index 74f089d87f..1f1d1a33b8 100644
--- a/target/s390x/kvm/kvm.c
+++ b/target/s390x/kvm/kvm.c
@@ -152,12 +152,15 @@ const KVMCapabilityInfo kvm_arch_required_capabilities[] = {
 static int cap_sync_regs;
 static int cap_async_pf;
 static int cap_mem_op;
+static int cap_mem_op_extension;
 static int cap_s390_irq;
 static int cap_ri;
 static int cap_hpage_1m;
 static int cap_vcpu_resets;
 static int cap_protected;
 
+static bool mem_op_storage_key_support;
+
 static int active_cmma;
 
 static int kvm_s390_query_mem_limit(uint64_t *memory_limit)
@@ -355,6 +358,8 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
     cap_sync_regs = kvm_check_extension(s, KVM_CAP_SYNC_REGS);
     cap_async_pf = kvm_check_extension(s, KVM_CAP_ASYNC_PF);
     cap_mem_op = kvm_check_extension(s, KVM_CAP_S390_MEM_OP);
+    cap_mem_op_extension = kvm_check_extension(s, KVM_CAP_S390_MEM_OP_EXTENSION);
+    mem_op_storage_key_support = cap_mem_op_extension > 0;
     cap_s390_irq = kvm_check_extension(s, KVM_CAP_S390_INJECT_IRQ);
     cap_vcpu_resets = kvm_check_extension(s, KVM_CAP_S390_VCPU_RESETS);
     cap_protected = kvm_check_extension(s, KVM_CAP_S390_PROTECTED);
@@ -843,6 +848,7 @@ int kvm_s390_mem_op(S390CPU *cpu, vaddr addr, uint8_t ar, void *hostbuf,
                        : KVM_S390_MEMOP_LOGICAL_READ,
         .buf = (uint64_t)hostbuf,
         .ar = ar,
+        .key = (cpu->env.psw.mask & PSW_MASK_KEY) >> PSW_SHIFT_KEY,
     };
     int ret;
 
@@ -852,6 +858,9 @@ int kvm_s390_mem_op(S390CPU *cpu, vaddr addr, uint8_t ar, void *hostbuf,
     if (!hostbuf) {
         mem_op.flags |= KVM_S390_MEMOP_F_CHECK_ONLY;
     }
+    if (mem_op_storage_key_support) {
+        mem_op.flags |= KVM_S390_MEMOP_F_SKEY_PROTECTION;
+    }
 
     ret = kvm_vcpu_ioctl(CPU(cpu), KVM_S390_MEM_OP, &mem_op);
     if (ret < 0) {
-- 
2.31.1