From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailapp01.imgtec.com ([195.59.15.196]:31800 "EHLO mailapp01.imgtec.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S23993874AbdAIUxc41nxP (ORCPT ); Mon, 9 Jan 2017 21:53:32 +0100 From: James Hogan Subject: [PATCH 7/10] KVM: MIPS/T&E: Use lockless GVA helpers for dyntrans Date: Mon, 9 Jan 2017 20:51:59 +0000 Message-ID: <8b8b6c1d2c495d1d5caf53c3386de34d19980576.1483993967.git-series.james.hogan@imgtec.com> MIME-Version: 1.0 In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit Return-Path: Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-subscribe: List-owner: List-post: List-archive: To: linux-mips@linux-mips.org Cc: James Hogan , Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Ralf Baechle , kvm@vger.kernel.org Message-ID: <20170109205159.IxCu0JB1I1yYrrVoCgiu-IwxIK0TzK432fs_iPq2uOA@z> Use the lockless GVA helpers to implement the dynamic translation of guest instructions. This will allow it to handle asynchronous TLB flushes when they are implemented. Signed-off-by: James Hogan Cc: Paolo Bonzini Cc: "Radim Krčmář" Cc: Ralf Baechle Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org --- arch/mips/kvm/dyntrans.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-) diff --git a/arch/mips/kvm/dyntrans.c b/arch/mips/kvm/dyntrans.c index 60ebf5862d2b..f8e772564d74 100644 --- a/arch/mips/kvm/dyntrans.c +++ b/arch/mips/kvm/dyntrans.c @@ -33,10 +33,32 @@ static int kvm_mips_trans_replace(struct kvm_vcpu *vcpu, u32 *opc, unsigned long vaddr = (unsigned long)opc; int err; +retry: + /* The GVA page table is still active so use the Linux TLB handlers */ + kvm_trap_emul_gva_lockless_begin(vcpu); err = put_user(replace.word, opc); + kvm_trap_emul_gva_lockless_end(vcpu); + if (unlikely(err)) { - kvm_err("%s: Invalid address: %p\n", __func__, opc); - return err; + /* + * We write protect clean pages in GVA page table so normal + * Linux TLB mod handler doesn't silently dirty the page. + * Its also possible we raced with a GVA invalidation. + * Try to force the page to become dirty. + */ + err = kvm_trap_emul_gva_fault(vcpu, vaddr, true); + if (unlikely(err)) { + kvm_info("%s: Address unwriteable: %p\n", + __func__, opc); + return -EFAULT; + } + + /* + * Try again. This will likely trigger a TLB refill, which will + * fetch the new dirty entry from the GVA page table, which + * should then succeed. + */ + goto retry; } __local_flush_icache_user_range(vaddr, vaddr + 4); -- git-series 0.8.10