{"id":2231348,"url":"http://patchwork.ozlabs.org/api/patches/2231348/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260430160307.634093-2-cohuck@redhat.com/","project":{"id":14,"url":"http://patchwork.ozlabs.org/api/projects/14/?format=json","name":"QEMU Development","link_name":"qemu-devel","list_id":"qemu-devel.nongnu.org","list_email":"qemu-devel@nongnu.org","web_url":"","scm_url":"","webscm_url":"","list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<20260430160307.634093-2-cohuck@redhat.com>","list_archive_url":null,"date":"2026-04-30T16:02:57","name":"[PULL,v2,01/11] target/s390x/kvm: Simplify the async pfault handling code","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"631e1d4cf187ebeb0aabe110257776ddcb44a996","submitter":{"id":71914,"url":"http://patchwork.ozlabs.org/api/people/71914/?format=json","name":"Cornelia Huck","email":"cohuck@redhat.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/qemu-devel/patch/20260430160307.634093-2-cohuck@redhat.com/mbox/","series":[{"id":502335,"url":"http://patchwork.ozlabs.org/api/series/502335/?format=json","web_url":"http://patchwork.ozlabs.org/project/qemu-devel/list/?series=502335","date":"2026-04-30T16:02:58","name":"[PULL,v2,01/11] target/s390x/kvm: Simplify the async pfault handling code","version":2,"mbox":"http://patchwork.ozlabs.org/series/502335/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/2231348/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/2231348/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@legolas.ozlabs.org","Authentication-Results":["legolas.ozlabs.org;\n\tdkim=pass (1024-bit key;\n unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256\n header.s=mimecast20190719 header.b=At23GtMH;\n\tdkim-atps=neutral","legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org\n (client-ip=209.51.188.17; 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a=rsa-sha256; c=relaxed/relaxed; d=redhat.com;\n s=mimecast20190719; t=1777565001;\n h=from:from:reply-to:subject:subject:date:date:message-id:message-id:\n to:to:cc:cc:mime-version:mime-version:content-type:content-type:\n content-transfer-encoding:content-transfer-encoding:\n in-reply-to:in-reply-to:references:references;\n bh=xRYLKOrmE7/oEuDtADR2OmYYnbN1a9jH/1mSe5dCafw=;\n b=At23GtMHrDQZeVwzahr8GA9GCqJQUEhEiuUI82v3kBMfnD1owbMWJHrqONK5A9u/m5TRQw\n 6qyocV+YnXryaciYQrDDbImM5EfTaoWQH6BOG6b9DtacGN1KNhze1JghRMcriYL8ofOSYA\n s0Iyzu1OJSEV5h8CM31k5x0AYIqPPM4=","X-MC-Unique":"ysVl5qMaMWKfXlaZvHY3Jg-1","X-Mimecast-MFC-AGG-ID":"ysVl5qMaMWKfXlaZvHY3Jg_1777564995","From":"Cornelia Huck ","To":"qemu-devel@nongnu.org","Cc":"qemu-s390x@nongnu.org, Thomas Huth ,\n Eric Farman ,\n Matthew Rosato ,\n Christian Borntraeger ,\n Cornelia Huck ","Subject":"[PULL v2 01/11] target/s390x/kvm: Simplify the async pfault handling\n code","Date":"Thu, 30 Apr 2026 18:02:57 +0200","Message-ID":"<20260430160307.634093-2-cohuck@redhat.com>","In-Reply-To":"<20260430160307.634093-1-cohuck@redhat.com>","References":"<20260430160307.634093-1-cohuck@redhat.com>","MIME-Version":"1.0","Content-type":"text/plain","Content-Transfer-Encoding":"8bit","X-Scanned-By":"MIMEDefang 3.4.1 on 10.30.177.111","Received-SPF":"pass client-ip=170.10.133.124; envelope-from=cohuck@redhat.com;\n helo=us-smtp-delivery-124.mimecast.com","X-Spam_score_int":"-20","X-Spam_score":"-2.1","X-Spam_bar":"--","X-Spam_report":"(-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001,\n DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1,\n RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001,\n SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no","X-Spam_action":"no action","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"qemu development ","List-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org"},"content":"From: Thomas Huth \n\nSince commit 126e7f78036 (\"kvm: require KVM_CAP_IOEVENTFD and\nKVM_CAP_IOEVENTFD_ANY_LENGTH\") we require at least kernel v4.4 to\nbe able to use KVM. KVM_CAP_ASYNC_PF is available in the kernel\nsince v3.15 and KVM_SYNC_PFAULT is available since kernel v3.18,\nso we can assume now that they are available in all supported\nkernels. Thus simplify the code a little bit by removing the\nchecks for these features.\n\nSigned-off-by: Thomas Huth \nReviewed-by: Eric Farman \nReviewed-by: Matthew Rosato \nAcked-by: Christian Borntraeger \nMessage-ID: <20260317134531.460141-1-thuth@redhat.com>\nSigned-off-by: Cornelia Huck \n---\n target/s390x/kvm/kvm.c | 52 +++++++++---------------------------------\n 1 file changed, 11 insertions(+), 41 deletions(-)","diff":"diff --git a/target/s390x/kvm/kvm.c b/target/s390x/kvm/kvm.c\nindex 54d28e37d4dd..133e8c12fd4d 100644\n--- a/target/s390x/kvm/kvm.c\n+++ b/target/s390x/kvm/kvm.c\n@@ -140,7 +140,6 @@ const KVMCapabilityInfo kvm_arch_required_capabilities[] = {\n KVM_CAP_LAST_INFO\n };\n \n-static int cap_async_pf;\n static int cap_mem_op;\n static int cap_mem_op_extension;\n static int cap_s390_irq;\n@@ -333,6 +332,7 @@ int kvm_arch_get_default_type(MachineState *ms)\n int kvm_arch_init(MachineState *ms, KVMState *s)\n {\n int required_caps[] = {\n+ KVM_CAP_ASYNC_PF,\n KVM_CAP_DEVICE_CTRL,\n KVM_CAP_SYNC_REGS,\n };\n@@ -340,7 +340,7 @@ int kvm_arch_init(MachineState *ms, KVMState *s)\n for (int i = 0; i < ARRAY_SIZE(required_caps); i++) {\n if (!kvm_check_extension(s, required_caps[i])) {\n error_report(\"KVM is missing capability #%d - \"\n- \"please use kernel 3.15 or newer\", required_caps[i]);\n+ \"please use kernel 4.4 or newer\", required_caps[i]);\n return -1;\n }\n }\n@@ -354,7 +354,6 @@ int kvm_arch_init(MachineState *ms, KVMState *s)\n return -1;\n }\n \n- cap_async_pf = kvm_check_extension(s, KVM_CAP_ASYNC_PF);\n cap_mem_op = kvm_check_extension(s, KVM_CAP_S390_MEM_OP);\n cap_mem_op_extension = kvm_check_extension(s, KVM_CAP_S390_MEM_OP_EXTENSION);\n mem_op_storage_key_support = cap_mem_op_extension > 0;\n@@ -466,7 +465,8 @@ static int can_sync_regs(CPUState *cs, int regs)\n }\n \n #define KVM_SYNC_REQUIRED_REGS (KVM_SYNC_GPRS | KVM_SYNC_ACRS | \\\n- KVM_SYNC_CRS | KVM_SYNC_PREFIX)\n+ KVM_SYNC_CRS | KVM_SYNC_PREFIX | \\\n+ KVM_SYNC_PFAULT)\n \n int kvm_arch_put_registers(CPUState *cs, KvmPutState level, Error **errp)\n {\n@@ -550,25 +550,10 @@ int kvm_arch_put_registers(CPUState *cs, KvmPutState level, Error **errp)\n }\n \n /* pfault parameters */\n- if (can_sync_regs(cs, KVM_SYNC_PFAULT)) {\n- cs->kvm_run->s.regs.pft = env->pfault_token;\n- cs->kvm_run->s.regs.pfs = env->pfault_select;\n- cs->kvm_run->s.regs.pfc = env->pfault_compare;\n- cs->kvm_run->kvm_dirty_regs |= KVM_SYNC_PFAULT;\n- } else if (cap_async_pf) {\n- r = kvm_set_one_reg(cs, KVM_REG_S390_PFTOKEN, &env->pfault_token);\n- if (r < 0) {\n- return r;\n- }\n- r = kvm_set_one_reg(cs, KVM_REG_S390_PFCOMPARE, &env->pfault_compare);\n- if (r < 0) {\n- return r;\n- }\n- r = kvm_set_one_reg(cs, KVM_REG_S390_PFSELECT, &env->pfault_select);\n- if (r < 0) {\n- return r;\n- }\n- }\n+ cs->kvm_run->s.regs.pft = env->pfault_token;\n+ cs->kvm_run->s.regs.pfs = env->pfault_select;\n+ cs->kvm_run->s.regs.pfc = env->pfault_compare;\n+ cs->kvm_run->kvm_dirty_regs |= KVM_SYNC_PFAULT;\n \n if (can_sync_regs(cs, KVM_SYNC_GSCB)) {\n memcpy(cs->kvm_run->s.regs.gscb, env->gscb, 32);\n@@ -673,24 +658,9 @@ int kvm_arch_get_registers(CPUState *cs, Error **errp)\n }\n \n /* pfault parameters */\n- if (can_sync_regs(cs, KVM_SYNC_PFAULT)) {\n- env->pfault_token = cs->kvm_run->s.regs.pft;\n- env->pfault_select = cs->kvm_run->s.regs.pfs;\n- env->pfault_compare = cs->kvm_run->s.regs.pfc;\n- } else if (cap_async_pf) {\n- r = kvm_get_one_reg(cs, KVM_REG_S390_PFTOKEN, &env->pfault_token);\n- if (r < 0) {\n- return r;\n- }\n- r = kvm_get_one_reg(cs, KVM_REG_S390_PFCOMPARE, &env->pfault_compare);\n- if (r < 0) {\n- return r;\n- }\n- r = kvm_get_one_reg(cs, KVM_REG_S390_PFSELECT, &env->pfault_select);\n- if (r < 0) {\n- return r;\n- }\n- }\n+ env->pfault_token = cs->kvm_run->s.regs.pft;\n+ env->pfault_select = cs->kvm_run->s.regs.pfs;\n+ env->pfault_compare = cs->kvm_run->s.regs.pfc;\n \n if (can_sync_regs(cs, KVM_SYNC_DIAG318)) {\n env->diag318_info = cs->kvm_run->s.regs.diag318;\n","prefixes":["PULL","v2","01/11"]}