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AJvYcCVHy+rGHoUULTltXlirc5j+v0TMN/rQG9KGDafdYoRh1kDQhglBNfCARORpwwFVzztCt6OsLREDT8vd@vger.kernel.org X-Gm-Message-State: AOJu0YyTMf5s8uqbJwy6PSVE2XIJryu7xCwK3yH8WzhPZnzFZ+DCjE/h 7RUiY3+Cq6cFtUZAl8jqnx5Vn9MXMYzUPWYbnveVkJn+cWhNp7UrbWxDKDjnI1VJjM+uYo3DGHw lmA== X-Google-Smtp-Source: AGHT+IHU1NaHt28BJAfE9+Eihx21gIRaHWD3wJUzNDiwOfeaS4l1n7K6hdxyKTp49hAFCJqVbhS/fDDFwRQ= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:9d:3983:ac13:c240]) (user=seanjc job=sendgmr) by 2002:a63:2545:0:b0:7e6:b4dd:fc0d with SMTP id 41be03b00d2f7-7ea535b0baemr20a12.7.1728584846518; Thu, 10 Oct 2024 11:27:26 -0700 (PDT) Reply-To: Sean Christopherson Date: Thu, 10 Oct 2024 11:24:15 -0700 In-Reply-To: <20241010182427.1434605-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-mips@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20241010182427.1434605-1-seanjc@google.com> X-Mailer: git-send-email 2.47.0.rc1.288.g06298d1525-goog Message-ID: <20241010182427.1434605-74-seanjc@google.com> Subject: [PATCH v13 73/85] KVM: PPC: Remove extra get_page() to fix page refcount leak From: Sean Christopherson To: Paolo Bonzini , Marc Zyngier , Oliver Upton , Tianrui Zhao , Bibo Mao , Huacai Chen , Michael Ellerman , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Sean Christopherson Cc: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, " =?utf-8?q?Alex_Benn=C3=A9e?= " , Yan Zhao , David Matlack , David Stevens , Andrew Jones Don't manually do get_page() when patching dcbz, as gfn_to_page() gifts the caller a reference. I.e. doing get_page() will leak the page due to not putting all references. Signed-off-by: Sean Christopherson --- arch/powerpc/kvm/book3s_pr.c | 1 - 1 file changed, 1 deletion(-) diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c index d7721297b9b6..cd7ab6d85090 100644 --- a/arch/powerpc/kvm/book3s_pr.c +++ b/arch/powerpc/kvm/book3s_pr.c @@ -652,7 +652,6 @@ static void kvmppc_patch_dcbz(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte) hpage_offset &= ~0xFFFULL; hpage_offset /= 4; - get_page(hpage); page = kmap_atomic(hpage); /* patch dcbz into reserved instruction, so we trap */