Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751734AbbD3MMw (ORCPT ); Thu, 30 Apr 2015 08:12:52 -0400 Received: from ip4-83-240-67-251.cust.nbox.cz ([83.240.67.251]:53601 "EHLO ip4-83-240-18-248.cust.nbox.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751308AbbD3MMe (ORCPT ); Thu, 30 Apr 2015 08:12:34 -0400 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Marc Zyngier , Shannon Zhao , Jiri Slaby Subject: [PATCH 3.12 17/63] arm64: KVM: force cache clean on page fault when caches are off Date: Thu, 30 Apr 2015 14:11:46 +0200 Message-Id: <8462018ebdfe8d208cb05a10a16ae74337d01ca9.1430387326.git.jslaby@suse.cz> X-Mailer: git-send-email 2.3.5 In-Reply-To: <45aaf85687dd6ac119c55c5ec0dbe0bef0e62235.1430387326.git.jslaby@suse.cz> References: <45aaf85687dd6ac119c55c5ec0dbe0bef0e62235.1430387326.git.jslaby@suse.cz> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4735 Lines: 127 From: Marc Zyngier 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 2d58b733c87689d3d5144e4ac94ea861cc729145 upstream. In order for the guest with caches off to observe data written contained in a given page, we need to make sure that page is committed to memory, and not just hanging in the cache (as guest accesses are completely bypassing the cache until it decides to enable it). For this purpose, hook into the coherent_icache_guest_page function and flush the region if the guest SCTLR_EL1 register doesn't show the MMU and caches as being enabled. The function also get renamed to coherent_cache_guest_page. Signed-off-by: Marc Zyngier Reviewed-by: Catalin Marinas Reviewed-by: Christoffer Dall Signed-off-by: Shannon Zhao Signed-off-by: Jiri Slaby --- arch/arm/include/asm/kvm_mmu.h | 6 +++--- arch/arm/kvm/mmu.c | 3 ++- arch/arm64/include/asm/kvm_mmu.h | 19 +++++++++++++------ 3 files changed, 18 insertions(+), 10 deletions(-) diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index 9b28c41f4ba9..ba285d7c7c57 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -105,7 +105,8 @@ static inline void kvm_set_s2pte_writable(pte_t *pte) struct kvm; -static inline void coherent_icache_guest_page(struct kvm *kvm, gfn_t gfn) +static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva, + unsigned long size) { /* * If we are going to insert an instruction page and the icache is @@ -120,8 +121,7 @@ static inline void coherent_icache_guest_page(struct kvm *kvm, gfn_t gfn) * need any kind of flushing (DDI 0406C.b - Page B3-1392). */ if (icache_is_pipt()) { - unsigned long hva = gfn_to_hva(kvm, gfn); - __cpuc_coherent_user_range(hva, hva + PAGE_SIZE); + __cpuc_coherent_user_range(hva, hva + size); } else if (!icache_is_vivt_asid_tagged()) { /* any kind of VIPT cache */ __flush_icache_all(); diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index fe59e4a19022..9e9260138ca0 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -540,6 +540,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, int ret; bool write_fault, writable; unsigned long mmu_seq; + unsigned long hva = gfn_to_hva(vcpu->kvm, gfn); struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache; write_fault = kvm_is_write_fault(kvm_vcpu_get_hsr(vcpu)); @@ -570,7 +571,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, return -EFAULT; new_pte = pfn_pte(pfn, PAGE_S2); - coherent_icache_guest_page(vcpu->kvm, gfn); + coherent_cache_guest_page(vcpu, hva, PAGE_SIZE); spin_lock(&vcpu->kvm->mmu_lock); if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index efe609c6a3c9..99229a613cd1 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -105,7 +105,6 @@ static inline bool kvm_is_write_fault(unsigned long esr) return true; } -static inline void kvm_clean_dcache_area(void *addr, size_t size) {} static inline void kvm_clean_pgd(pgd_t *pgd) {} static inline void kvm_clean_pmd_entry(pmd_t *pmd) {} static inline void kvm_clean_pte(pte_t *pte) {} @@ -118,18 +117,26 @@ static inline void kvm_set_s2pte_writable(pte_t *pte) struct kvm; -static inline void coherent_icache_guest_page(struct kvm *kvm, gfn_t gfn) +#define kvm_flush_dcache_to_poc(a,l) __flush_dcache_area((a), (l)) + +static inline bool vcpu_has_cache_enabled(struct kvm_vcpu *vcpu) +{ + return (vcpu_sys_reg(vcpu, SCTLR_EL1) & 0b101) == 0b101; +} + +static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva, + unsigned long size) { + if (!vcpu_has_cache_enabled(vcpu)) + kvm_flush_dcache_to_poc((void *)hva, size); + if (!icache_is_aliasing()) { /* PIPT */ - unsigned long hva = gfn_to_hva(kvm, gfn); - flush_icache_range(hva, hva + PAGE_SIZE); + flush_icache_range(hva, hva + size); } else if (!icache_is_aivivt()) { /* non ASID-tagged VIVT */ /* any kind of VIPT cache */ __flush_icache_all(); } } -#define kvm_flush_dcache_to_poc(a,l) __flush_dcache_area((a), (l)) - #endif /* __ASSEMBLY__ */ #endif /* __ARM64_KVM_MMU_H__ */ -- 2.3.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/