From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8FC9D445ADD; Fri, 28 Aug 2026 11:54:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.158.5 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787918106; cv=none; b=VOiKBKfYYl7YfFoGEzF9qJW9ELVOVgUd7qGJWGc7XFLzfB3mjAIjlo/6vHRzAHb+N7D8TJ55WFlsmxx5wxF+VotgkeKu6EcL9dCDqeOE9A/gmTXBm40joXMxiNKcOBzkLlXzlSBjKFCGARDRuAKReazCE98KHh/lh9c9Lkc8OUg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787918106; c=relaxed/simple; bh=EzLjQ3QYSPWodEBYgfMxFm7MZ+LhS3n4I0WeCxb34YE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SaU4xDC+mGNmL2DK3mIRLNCUQ22kZxX9SWqjWuLEd9STslowzh4jCLISTq1lUx+/pNC0cWOwhXAd3OTyNOAARWKxQ6HPQ1A5dDmkq9OYMiI1CY1Eln/j2yWenx2wXnwL/5MUVEzAQpuriWTcgsBt7a4wGY0GRFGzQuhZLJgFP5M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com; spf=pass smtp.mailfrom=linux.ibm.com; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b=liw2NxWq; arc=none smtp.client-ip=148.163.158.5 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="liw2NxWq" Received: from pps.filterd (m0353725.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 67SAWYBJ604147; Fri, 28 Aug 2026 11:54:47 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:date:from:in-reply-to:message-id :mime-version:references:subject:to; s=pp1; bh=MSGaBAdIZ/lnnJ342 a9nyiDB5OQtvOqXd+WYx37VX88=; b=liw2NxWq0eKK9YWAb2XDSzwYbFxS5iWWy 8F4zQKohQp5ddCadpmq1EzlPZZnRSEMe3c3vI7q6eQDp8ZZhsX+oDx83AzkGa0Mm DgpgUA0WMlPySg5MDhzv/YdOQjfKeKNlAbM6wNrgdW/40sN9A9FFaH6Lt16glJ/W ckxzOdm7mDaNSNMZsbvsWMkx4VJD+pWcYWAXoS5H3pWzSxMuilOuv4X7mCjRbk12 KuKhsAXmod/u2whc8ZJEWU18MYylud4h7Wy+w8MEDWBSqCB363qmcX79iVNyymrw 2O7JerO11F1ZUqPuiMVCIqNq9WPUOOaM25c8uy8Ao0FQ2zT9znNRw== Received: from ppma13.dal12v.mail.ibm.com (dd.9e.1632.ip4.static.sl-reverse.com [50.22.158.221]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4g726f3rjf-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 28 Aug 2026 11:54:47 +0000 (GMT) Received: from pps.filterd (ppma13.dal12v.mail.ibm.com [127.0.0.1]) by ppma13.dal12v.mail.ibm.com (8.18.1.7/8.18.1.7) with ESMTP id 67SBfGHR031558; Fri, 28 Aug 2026 11:54:46 GMT Received: from smtprelay04.fra02v.mail.ibm.com ([9.218.2.228]) by ppma13.dal12v.mail.ibm.com (PPS) with ESMTPS id 4g7ragwsuq-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 28 Aug 2026 11:54:46 +0000 (GMT) Received: from smtpav07.fra02v.mail.ibm.com (smtpav07.fra02v.mail.ibm.com [10.20.54.106]) by smtprelay04.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 67SBseld7799070 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 28 Aug 2026 11:54:40 GMT Received: from smtpav07.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7CB572004B; Fri, 28 Aug 2026 11:54:40 +0000 (GMT) Received: from smtpav07.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5996620040; Fri, 28 Aug 2026 11:54:40 +0000 (GMT) Received: from p-imbrenda.ehn-de.ibm.com (unknown [9.224.75.30]) by smtpav07.fra02v.mail.ibm.com (Postfix) with ESMTP; Fri, 28 Aug 2026 11:54:40 +0000 (GMT) From: Claudio Imbrenda To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, linux-s390@vger.kernel.org, borntraeger@de.ibm.com, frankja@linux.ibm.com, david@kernel.org, seiden@linux.ibm.com, nrb@linux.ibm.com, schlameuss@linux.ibm.com, gra@linux.ibm.com Subject: [PATCH v3 5/8] KVM: s390: Move all code into s390_kvm_mmu_prepare_memory_region() Date: Fri, 28 Aug 2026 13:54:36 +0200 Message-ID: <20260828115439.145885-6-imbrenda@linux.ibm.com> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260828115439.145885-1-imbrenda@linux.ibm.com> References: <20260828115439.145885-1-imbrenda@linux.ibm.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Authority-Analysis: v=2.4 cv=TfimcxQh c=1 sm=1 tr=0 ts=6a917707 cx=c_pps a=AfN7/Ok6k8XGzOShvHwTGQ==:117 a=AfN7/Ok6k8XGzOShvHwTGQ==:17 a=Sv0fKeRqtYgA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=V8glGbnc2Ofi9Qvn3v5h:22 a=VnNF1IyMAAAA:8 a=XQGuvBUbV6v71_fLNr4A:9 X-Proofpoint-Spam-Info: AW1haW4tMjYwODI4MDA5OSBTYWx0ZWRfX05wObuSFoToM S0wBXZutBZrTzCMqTBpIycEyt04QGdppnT1pK4sKcjq9rCbCDhRYz7QLirhTXkq9S+/icE7V2e7 6J2KYwvmUEYzTvlmilDHXOEjMxTokGY= X-Proofpoint-GUID: f91U8Li3JdN0YHzWtKX5wfF1Gexa2gFz X-Proofpoint-ORIG-GUID: f91U8Li3JdN0YHzWtKX5wfF1Gexa2gFz X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwODI4MDA5OSBTYWx0ZWRfX2czpOgQKckBg NoMso2/EAhcTXaBe6MIcB9uYPwnttKbAk3//nMh+lzNs51ZQ1yf6XvQVSqNLdhlaXJIMaJxg4rK Whw2BFdwe5LPKsssIUH13B2C2gVPeap6eoz2jATgO/NrwiSPBxXrSaiVQ4rfs71xz10mkDo0WaS wKW5Cn/dtWD2JstxgICiSU3sVtooA0956GG61A61HGMdXgcSkQTrJiH5y4r3BOL9vY9XRvH1xbp 8RmrwCfMVUWxpI6RQSz9Mq3mLFTkcmInBTkx53I07ZwryrSCC14vnWay0SFpoe2YwHdv42YZtYJ VRow2SmgembeWa6PPM27njmI9wcCZq28Rzw0IpWfIXJ8chUosFqc79jatI2c6uTVH1x3ZJbKm+o +BzpNq3QTcr09ZDFAEGGLEBARaGR/wprz4SLn83mMJTIEN+qVuLHsfy1GB6WQZCwm1mmGywXhOg 4eG9iUyHYojc0CKU02A== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-08-28_03,2026-08-27_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 spamscore=0 bulkscore=0 malwarescore=0 priorityscore=1501 lowpriorityscore=0 clxscore=1015 phishscore=0 impostorscore=0 adultscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2608280099 Move all code from s390_kvm_mmu_commit_memory_region() into s390_kvm_mmu_prepare_memory_region(). This allows the function to fail gracefully if needed. The previous behaviour was to print a warning and continue execution with page tables inconsistent with the memslots. Fixes: e38c884df921 ("KVM: s390: Switch to new gmap") Signed-off-by: Claudio Imbrenda --- arch/s390/kvm/gmap/kvm_mmu.c | 89 +++++++++++++++--------------------- arch/s390/kvm/gmap/kvm_mmu.h | 4 -- arch/s390/kvm/s390/s390.c | 1 - 3 files changed, 36 insertions(+), 58 deletions(-) diff --git a/arch/s390/kvm/gmap/kvm_mmu.c b/arch/s390/kvm/gmap/kvm_mmu.c index 4c8054e18490..c2ffb5e59ec6 100644 --- a/arch/s390/kvm/gmap/kvm_mmu.c +++ b/arch/s390/kvm/gmap/kvm_mmu.c @@ -47,6 +47,9 @@ int s390_kvm_mmu_prepare_memory_region(struct kvm *kvm, struct kvm_memory_slot *new, enum kvm_mr_change change) { + struct kvm_s390_mmu_cache *mc __free(kvm_s390_mmu_cache) = NULL; + int rc = 0; + if (kvm_is_ucontrol(kvm) && new && new->id < KVM_USER_MEM_SLOTS) return -EINVAL; @@ -61,6 +64,10 @@ int s390_kvm_mmu_prepare_memory_region(struct kvm *kvm, * and munmap() stuff in this slot after doing this call at any * time. */ + if (change != KVM_MR_MOVE && change != KVM_MR_CREATE) { + WARN(1, "Unknown KVM MR CHANGE: %d\n", change); + return -EINVAL; + } if (new->userspace_addr & ~PAGE_MASK) return -EINVAL; if ((new->base_gfn + new->npages) * PAGE_SIZE > kvm->arch.mem_limit) @@ -69,65 +76,41 @@ int s390_kvm_mmu_prepare_memory_region(struct kvm *kvm, return -EINVAL; } - if (!kvm_s390_is_migration_mode(kvm)) - return 0; - - /* - * Turn off migration mode when: - * - userspace creates a new memslot with dirty logging off, - * - userspace modifies an existing memslot (MOVE or FLAGS_ONLY) and - * dirty logging is turned off. - * Migration mode expects dirty page logging being enabled to store - * its dirty bitmap. - */ - if (change != KVM_MR_DELETE && - !(new->flags & KVM_MEM_LOG_DIRTY_PAGES)) - WARN(kvm_s390_vm_stop_migration(kvm), - "Failed to stop migration mode"); - - return 0; -} - -void s390_kvm_mmu_commit_memory_region(struct kvm *kvm, - struct kvm_memory_slot *old, - const struct kvm_memory_slot *new, - enum kvm_mr_change change) -{ - struct kvm_s390_mmu_cache *mc __free(kvm_s390_mmu_cache) = NULL; - int rc = 0; - - guard(mutex)(&kvm->slots_arch_lock); + if (kvm->arch.migration_mode) { + /* + * Turn off migration mode when: + * - userspace creates a new memslot with dirty logging off, + * - userspace modifies an existing memslot (MOVE or FLAGS_ONLY) + * and dirty logging is turned off. + * Migration mode expects dirty page logging being enabled to + * store its dirty bitmap. + */ + if (change != KVM_MR_DELETE && + !(new->flags & KVM_MEM_LOG_DIRTY_PAGES)) + WARN(kvm_s390_vm_stop_migration(kvm), + "Failed to stop migration mode"); + } if (change == KVM_MR_FLAGS_ONLY) - return; - - mc = kvm_s390_new_mmu_cache(); - if (!mc) { - rc = -ENOMEM; - goto out; + return 0; + if (change != KVM_MR_DELETE) { + /* Enough capacity to add a new memslot */ + mc = kvm_s390_new_mmu_cache(); + if (!mc) + return -ENOMEM; } - scoped_guard(write_lock, &kvm->mmu_lock) { kvm_s390_update_cmma_dirty(kvm, old); - switch (change) { - case KVM_MR_DELETE: - rc = dat_delete_slot(kvm->arch.gmap->asce, old->base_gfn, old->npages); - break; - case KVM_MR_MOVE: + if (change == KVM_MR_DELETE || change == KVM_MR_MOVE) rc = dat_delete_slot(kvm->arch.gmap->asce, old->base_gfn, old->npages); - if (rc) - break; - fallthrough; - case KVM_MR_CREATE: + if (!rc && (change == KVM_MR_MOVE || change == KVM_MR_CREATE)) rc = dat_create_slot(mc, kvm->arch.gmap->asce, new->base_gfn, new->npages); - break; - case KVM_MR_FLAGS_ONLY: - break; - default: - WARN(1, "Unknown KVM MR CHANGE: %d\n", change); - } } -out: - if (rc) - pr_warn("failed to commit memory region\n"); + /* + * Can only be triggered if dat_{create,delete}_slot() found an + * internal inconsistency or if the mmu cache ran out of memory; + * both should be impossible. + */ + KVM_BUG_ON(rc, kvm); + return rc; } diff --git a/arch/s390/kvm/gmap/kvm_mmu.h b/arch/s390/kvm/gmap/kvm_mmu.h index cdbd390bd33c..43cde61bae03 100644 --- a/arch/s390/kvm/gmap/kvm_mmu.h +++ b/arch/s390/kvm/gmap/kvm_mmu.h @@ -10,9 +10,5 @@ int s390_kvm_mmu_prepare_memory_region(struct kvm *kvm, const struct kvm_memory_slot *old, struct kvm_memory_slot *new, enum kvm_mr_change change); -void s390_kvm_mmu_commit_memory_region(struct kvm *kvm, - struct kvm_memory_slot *old, - const struct kvm_memory_slot *new, - enum kvm_mr_change change); #endif /* ARCH_KVM_GMAP_KVM_MMU_H */ diff --git a/arch/s390/kvm/s390/s390.c b/arch/s390/kvm/s390/s390.c index 8f7e09d7d049..eca4a4359ab2 100644 --- a/arch/s390/kvm/s390/s390.c +++ b/arch/s390/kvm/s390/s390.c @@ -5781,7 +5781,6 @@ void kvm_arch_commit_memory_region(struct kvm *kvm, struct kvm_memory_slot *old, const struct kvm_memory_slot *new, enum kvm_mr_change change) { - s390_kvm_mmu_commit_memory_region(kvm, old, new, change); } /** -- 2.55.0