From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C036FCAC582 for ; Fri, 12 Sep 2025 13:43:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:Cc :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=S8NHCao++QUY42UcyMOaIABTHbYxHI+9sxpUl3oiMgs=; b=eTBWoM3AdO6hvU P/WDxK1V1l9ITsF792n3yWoEg+kdNrEO5oNnRrYJVoTh4PF5arHxKIiQE34LtYLHngHgfWCau1VJC 2kY32N9CQBR6QThWc8dlVvyCzxiUbvew+ATqgilpzcQ8V65vMXsDWSvlQ4Xqd2eWC40IYM2Whv2Az iP1BSkgM6GeXK2wf+yguD2l5biQhpF6QkYrtIcG3Dy5qX7VQq3g2YgVq2QSsTVrJcoMiJctnLEKZA u8X4px13OZPopkMIrZHrhAFvKsqzixk0A5hbjDTcPtXmhAquFkK9yNKz/2DSbwVb+olOJm3NsKx8v jAhwI9lqV1k7NFB5uV4g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1ux448-00000009dBN-0JKv; Fri, 12 Sep 2025 13:43:52 +0000 Received: from out30-119.freemail.mail.aliyun.com ([115.124.30.119]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1ux444-00000009d8U-0b48; Fri, 12 Sep 2025 13:43:50 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1757684621; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=JEFJ+1KMaBT9yMuJVI/v+rlWqZb3XjQ/Sg99JRs7BGc=; b=GcXc1aU/XuTEVnXNEAFFI6pcvOwhCKB1TJU06nOFlJ6FaXks3n6tQ3y3psG7sLsD0CsVmx85MQj7amOE9kt4G5bLj4Hc+Bc/RDq7z3cIncSAT4G7R/drMTrAZV/QUs1OaDicQnyuZ+0gdgoobmPRtDT5cA58bXQ4EcZ3HVbS9pE= Received: from localhost.localdomain(mailfrom:fangyu.yu@linux.alibaba.com fp:SMTPD_---0WnrFL5n_1757684616 cluster:ay36) by smtp.aliyun-inc.com; Fri, 12 Sep 2025 21:43:38 +0800 From: fangyu.yu@linux.alibaba.com To: anup@brainfault.org, atish.patra@linux.dev, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, alex@ghiti.fr, pbonzini@redhat.com, graf@amazon.com, jiangyifei@huawei.com Cc: guoren@kernel.org, kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Fangyu Yu Subject: [PATCH] RISC-V: KVM: Fix guest page fault within HLV* instructions Date: Fri, 12 Sep 2025 21:43:32 +0800 Message-Id: <20250912134332.22053-1-fangyu.yu@linux.alibaba.com> X-Mailer: git-send-email 2.39.3 (Apple Git-146) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250912_064348_918484_2FAD1A6B X-CRM114-Status: UNSURE ( 6.85 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org From: Fangyu Yu When executing HLV* instructions at the HS mode, a guest page fault may occur when a g-stage page table migration between triggering the virtual instruction exception and executing the HLV* instruction. This may be a corner case, and one simpler way to handle this is to re-execute the instruction where the virtual instruction exception occurred, and the guest page fault will be automatically handled. Fixes: 9f7013265112 ("RISC-V: KVM: Handle MMIO exits for VCPU") Signed-off-by: Fangyu Yu --- arch/riscv/kvm/vcpu_insn.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/arch/riscv/kvm/vcpu_insn.c b/arch/riscv/kvm/vcpu_insn.c index 97dec18e6989..a8b93aa4d8ec 100644 --- a/arch/riscv/kvm/vcpu_insn.c +++ b/arch/riscv/kvm/vcpu_insn.c @@ -448,7 +448,12 @@ int kvm_riscv_vcpu_virtual_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, insn = kvm_riscv_vcpu_unpriv_read(vcpu, true, ct->sepc, &utrap); - if (utrap.scause) { + switch (utrap.scause) { + case 0: + break; + case EXC_LOAD_GUEST_PAGE_FAULT: + return KVM_INSN_CONTINUE_SAME_SEPC; + default: utrap.sepc = ct->sepc; kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); return 1; @@ -503,7 +508,12 @@ int kvm_riscv_vcpu_mmio_load(struct kvm_vcpu *vcpu, struct kvm_run *run, */ insn = kvm_riscv_vcpu_unpriv_read(vcpu, true, ct->sepc, &utrap); - if (utrap.scause) { + switch (utrap.scause) { + case 0: + break; + case EXC_LOAD_GUEST_PAGE_FAULT: + return KVM_INSN_CONTINUE_SAME_SEPC; + default: /* Redirect trap if we failed to read instruction */ utrap.sepc = ct->sepc; kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); @@ -629,7 +639,12 @@ int kvm_riscv_vcpu_mmio_store(struct kvm_vcpu *vcpu, struct kvm_run *run, */ insn = kvm_riscv_vcpu_unpriv_read(vcpu, true, ct->sepc, &utrap); - if (utrap.scause) { + switch (utrap.scause) { + case 0: + break; + case EXC_LOAD_GUEST_PAGE_FAULT: + return KVM_INSN_CONTINUE_SAME_SEPC; + default: /* Redirect trap if we failed to read instruction */ utrap.sepc = ct->sepc; kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); -- 2.49.0 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv