From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Tue, 14 May 2013 11:27:20 +0200 (CEST) Received: from mx1.redhat.com ([209.132.183.28]:32654 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S6818014Ab3ENJ1QYrRej (ORCPT ); Tue, 14 May 2013 11:27:16 +0200 Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r4E9R8lb008351 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Tue, 14 May 2013 05:27:08 -0400 Received: from dhcp-1-237.tlv.redhat.com (dhcp-4-26.tlv.redhat.com [10.35.4.26]) by int-mx02.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id r4E9R690011488; Tue, 14 May 2013 05:27:07 -0400 Received: by dhcp-1-237.tlv.redhat.com (Postfix, from userid 13519) id 620BA18D3DE; Tue, 14 May 2013 12:27:05 +0300 (IDT) Date: Tue, 14 May 2013 12:27:05 +0300 From: Gleb Natapov To: Sanjay Lal Cc: kvm@vger.kernel.org, linux-mips@linux-mips.org, mtosatti@redhat.com, ralf@linux-mips.org Subject: Re: [PATCH 2/2] KVM/MIPS32: Wrap calls to gfn_to_pfn() with srcu_read_lock/unlock() Message-ID: <20130514092705.GD20995@redhat.com> References: <1368476500-20031-1-git-send-email-sanjayl@kymasys.com> <1368476500-20031-3-git-send-email-sanjayl@kymasys.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1368476500-20031-3-git-send-email-sanjayl@kymasys.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.12 Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 36401 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: gleb@redhat.com Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips On Mon, May 13, 2013 at 01:21:40PM -0700, Sanjay Lal wrote: > Explain kvm_mips_map_page() changes here please. The text from the cover letter does not go into git history. > Signed-off-by: Sanjay Lal > --- > arch/mips/kvm/kvm_tlb.c | 38 +++++++++++++++++++++++++++++--------- > 1 file changed, 29 insertions(+), 9 deletions(-) > > diff --git a/arch/mips/kvm/kvm_tlb.c b/arch/mips/kvm/kvm_tlb.c > index 89511a9..218075f 100644 > --- a/arch/mips/kvm/kvm_tlb.c > +++ b/arch/mips/kvm/kvm_tlb.c > @@ -16,7 +16,10 @@ > #include > #include > #include > +#include > #include > +#include > + > > #include > #include > @@ -36,6 +39,8 @@ > /* Use VZ EntryHi.EHINV to invalidate TLB entries */ > #define UNIQUE_ENTRYHI(idx) (CKSEG0 + ((idx) << (PAGE_SHIFT + 1))) > > +EXPORT_SYMBOL(min_low_pfn); /* defined by bootmem.c, but not exported by generic code */ > + What you need this for? It is not used anywhere in this patch and by mips/kvm code in general. > atomic_t kvm_mips_instance; > EXPORT_SYMBOL(kvm_mips_instance); > > @@ -169,21 +174,27 @@ void kvm_mips_dump_shadow_tlbs(struct kvm_vcpu *vcpu) > } > } > > -static void kvm_mips_map_page(struct kvm *kvm, gfn_t gfn) > +static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn) > { > + int srcu_idx, err = 0; > pfn_t pfn; > > if (kvm->arch.guest_pmap[gfn] != KVM_INVALID_PAGE) > - return; > + return 0; > > + srcu_idx = srcu_read_lock(&kvm->srcu); Use tabs to indent. > pfn = kvm_mips_gfn_to_pfn(kvm, gfn); > > if (kvm_mips_is_error_pfn(pfn)) { > - panic("Couldn't get pfn for gfn %#" PRIx64 "!\n", gfn); > + kvm_err("Couldn't get pfn for gfn %#" PRIx64 "!\n", gfn); > + err = -EFAULT; > + goto out; > } > > kvm->arch.guest_pmap[gfn] = pfn; > - return; > +out: > + srcu_read_unlock(&kvm->srcu, srcu_idx); > + return err; > } > > /* Translate guest KSEG0 addresses to Host PA */ > @@ -207,7 +218,10 @@ unsigned long kvm_mips_translate_guest_kseg0_to_hpa(struct kvm_vcpu *vcpu, > gva); > return KVM_INVALID_PAGE; > } > - kvm_mips_map_page(vcpu->kvm, gfn); > + > + if (kvm_mips_map_page(vcpu->kvm, gfn) < 0) > + return KVM_INVALID_ADDR; > + > return (kvm->arch.guest_pmap[gfn] << PAGE_SHIFT) + offset; > } > > @@ -310,8 +324,11 @@ int kvm_mips_handle_kseg0_tlb_fault(unsigned long badvaddr, > even = !(gfn & 0x1); > vaddr = badvaddr & (PAGE_MASK << 1); > > - kvm_mips_map_page(vcpu->kvm, gfn); > - kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1); > + if (kvm_mips_map_page(vcpu->kvm, gfn) < 0) > + return -1; > + > + if (kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1) < 0) > + return -1; > > if (even) { > pfn0 = kvm->arch.guest_pmap[gfn]; > @@ -389,8 +406,11 @@ kvm_mips_handle_mapped_seg_tlb_fault(struct kvm_vcpu *vcpu, > pfn0 = 0; > pfn1 = 0; > } else { > - kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo0) >> PAGE_SHIFT); > - kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo1) >> PAGE_SHIFT); > + if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo0) >> PAGE_SHIFT) < 0) > + return -1; > + > + if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo1) >> PAGE_SHIFT) < 0) > + return -1; > > pfn0 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo0) >> PAGE_SHIFT]; > pfn1 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo1) >> PAGE_SHIFT]; > -- > 1.7.11.3 -- Gleb.