From patchwork Mon Feb 27 03:33:42 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Mackerras X-Patchwork-Id: 9592667 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id A93F960471 for ; Mon, 27 Feb 2017 04:00:00 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 65ADF28346 for ; Mon, 27 Feb 2017 04:00:00 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 582FE2836D; Mon, 27 Feb 2017 04:00:00 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9C1B228346 for ; Mon, 27 Feb 2017 03:59:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751447AbdB0D74 (ORCPT ); Sun, 26 Feb 2017 22:59:56 -0500 Received: from ozlabs.org ([103.22.144.67]:55875 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751306AbdB0D74 (ORCPT ); Sun, 26 Feb 2017 22:59:56 -0500 Received: by ozlabs.org (Postfix, from userid 1003) id 3vWnP84VlBz9s9r; Mon, 27 Feb 2017 14:33:48 +1100 (AEDT) Date: Mon, 27 Feb 2017 14:33:42 +1100 From: Paul Mackerras To: linuxppc-dev@ozlabs.org, kvm@vger.kernel.org Cc: kvm-ppc@vger.kernel.org Subject: [PATCH] KVM: PPC: Book3S HV: Fix software walk of guest process page tables Message-ID: <20170227033342.GB3591@fergus.ozlabs.ibm.com> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.24 (2015-08-30) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This fixes some bugs in the code that walks the guest's page tables. These bugs cause MMIO emulation to fail whenever the guest is in virtial mode (MMU on), leading to the guest hanging if it tried to access a virtio device. The first bug was that when reading the guest's process table, we were using the whole of arch->process_table, not just the field that contains the process table base address. The second bug was that the mask used when reading the process table entry to get the radix tree base address, RPDB_MASK, had the wrong value. Fixes: 9e04ba69beec ("KVM: PPC: Book3S HV: Add basic infrastructure for radix guests") Fixes: e99833448c5f ("powerpc/mm/radix: Add partition table format & callback") Signed-off-by: Paul Mackerras --- arch/powerpc/include/asm/book3s/64/mmu.h | 3 ++- arch/powerpc/kvm/book3s_64_mmu_radix.c | 5 +++-- 2 files changed, 5 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/include/asm/book3s/64/mmu.h b/arch/powerpc/include/asm/book3s/64/mmu.h index d73e9df..440f342 100644 --- a/arch/powerpc/include/asm/book3s/64/mmu.h +++ b/arch/powerpc/include/asm/book3s/64/mmu.h @@ -46,7 +46,7 @@ extern struct patb_entry *partition_tb; /* Bits in patb0 field */ #define PATB_HR (1UL << 63) -#define RPDB_MASK 0x0ffffffffffff00fUL +#define RPDB_MASK 0x0fffffffffffff00UL #define RPDB_SHIFT (1UL << 8) #define RTS1_SHIFT 61 /* top 2 bits of radix tree size */ #define RTS1_MASK (3UL << RTS1_SHIFT) @@ -57,6 +57,7 @@ extern struct patb_entry *partition_tb; /* Bits in patb1 field */ #define PATB_GR (1UL << 63) /* guest uses radix; must match HR */ #define PRTS_MASK 0x1f /* process table size field */ +#define PRTB_MASK 0x0ffffffffffff000UL /* * Limit process table to PAGE_SIZE table. This diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c index 4344651..f6b3e67 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_radix.c +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c @@ -32,6 +32,7 @@ int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, u32 pid; int ret, level, ps; __be64 prte, rpte; + unsigned long ptbl; unsigned long root, pte, index; unsigned long rts, bits, offset; unsigned long gpa; @@ -53,8 +54,8 @@ int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, return -EINVAL; /* Read partition table to find root of tree for effective PID */ - ret = kvm_read_guest(kvm, kvm->arch.process_table + pid * 16, - &prte, sizeof(prte)); + ptbl = (kvm->arch.process_table & PRTB_MASK) + (pid * 16); + ret = kvm_read_guest(kvm, ptbl, &prte, sizeof(prte)); if (ret) return ret;