From 2d58b733c87689d3d5144e4ac94ea861cc729145 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 14 Jan 2014 19:13:10 +0000 Subject: arm64: KVM: force cache clean on page fault when caches are off 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 --- arch/arm/include/asm/kvm_mmu.h | 4 ++-- arch/arm/kvm/mmu.c | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index 2d122adcdb22..6d0f3d3023b7 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -116,8 +116,8 @@ static inline void kvm_set_s2pmd_writable(pmd_t *pmd) struct kvm; -static inline void coherent_icache_guest_page(struct kvm *kvm, hva_t hva, - unsigned long size) +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 diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index 7789857d1470..fc71a8df0e13 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -715,7 +715,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, kvm_set_s2pmd_writable(&new_pmd); kvm_set_pfn_dirty(pfn); } - coherent_icache_guest_page(kvm, hva & PMD_MASK, PMD_SIZE); + coherent_cache_guest_page(vcpu, hva & PMD_MASK, PMD_SIZE); ret = stage2_set_pmd_huge(kvm, memcache, fault_ipa, &new_pmd); } else { pte_t new_pte = pfn_pte(pfn, PAGE_S2); @@ -723,7 +723,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, kvm_set_s2pte_writable(&new_pte); kvm_set_pfn_dirty(pfn); } - coherent_icache_guest_page(kvm, hva, PAGE_SIZE); + coherent_cache_guest_page(vcpu, hva, PAGE_SIZE); ret = stage2_set_pte(kvm, memcache, fault_ipa, &new_pte, false); } -- cgit v1.2.3 From a3c8bd31af260a17d626514f636849ee1cd1f63e Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 18 Feb 2014 14:29:03 +0000 Subject: ARM: KVM: introduce kvm_p*d_addr_end The use of p*d_addr_end with stage-2 translation is slightly dodgy, as the IPA is 40bits, while all the p*d_addr_end helpers are taking an unsigned long (arm64 is fine with that as unligned long is 64bit). The fix is to introduce 64bit clean versions of the same helpers, and use them in the stage-2 page table code. Signed-off-by: Marc Zyngier Acked-by: Catalin Marinas Reviewed-by: Christoffer Dall --- arch/arm/include/asm/kvm_mmu.h | 13 +++++++++++++ arch/arm/kvm/mmu.c | 10 +++++----- 2 files changed, 18 insertions(+), 5 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index 6d0f3d3023b7..891afe78311a 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -114,6 +114,19 @@ static inline void kvm_set_s2pmd_writable(pmd_t *pmd) pmd_val(*pmd) |= L_PMD_S2_RDWR; } +/* Open coded p*d_addr_end that can deal with 64bit addresses */ +#define kvm_pgd_addr_end(addr, end) \ +({ u64 __boundary = ((addr) + PGDIR_SIZE) & PGDIR_MASK; \ + (__boundary - 1 < (end) - 1)? __boundary: (end); \ +}) + +#define kvm_pud_addr_end(addr,end) (end) + +#define kvm_pmd_addr_end(addr, end) \ +({ u64 __boundary = ((addr) + PMD_SIZE) & PMD_MASK; \ + (__boundary - 1 < (end) - 1)? __boundary: (end); \ +}) + struct kvm; static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva, diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index fc71a8df0e13..c1c08b240f35 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -145,7 +145,7 @@ static void unmap_range(struct kvm *kvm, pgd_t *pgdp, pgd = pgdp + pgd_index(addr); pud = pud_offset(pgd, addr); if (pud_none(*pud)) { - addr = pud_addr_end(addr, end); + addr = kvm_pud_addr_end(addr, end); continue; } @@ -155,13 +155,13 @@ static void unmap_range(struct kvm *kvm, pgd_t *pgdp, * move on. */ clear_pud_entry(kvm, pud, addr); - addr = pud_addr_end(addr, end); + addr = kvm_pud_addr_end(addr, end); continue; } pmd = pmd_offset(pud, addr); if (pmd_none(*pmd)) { - addr = pmd_addr_end(addr, end); + addr = kvm_pmd_addr_end(addr, end); continue; } @@ -176,10 +176,10 @@ static void unmap_range(struct kvm *kvm, pgd_t *pgdp, */ if (kvm_pmd_huge(*pmd) || page_empty(pte)) { clear_pmd_entry(kvm, pmd, addr); - next = pmd_addr_end(addr, end); + next = kvm_pmd_addr_end(addr, end); if (page_empty(pmd) && !page_empty(pud)) { clear_pud_entry(kvm, pud, addr); - next = pud_addr_end(addr, end); + next = kvm_pud_addr_end(addr, end); } } -- cgit v1.2.3 From 9d218a1fcf4c6b759d442ef702842fae92e1ea61 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 15 Jan 2014 12:50:23 +0000 Subject: arm64: KVM: flush VM pages before letting the guest enable caches When the guest runs with caches disabled (like in an early boot sequence, for example), all the writes are diectly going to RAM, bypassing the caches altogether. Once the MMU and caches are enabled, whatever sits in the cache becomes suddenly visible, which isn't what the guest expects. A way to avoid this potential disaster is to invalidate the cache when the MMU is being turned on. For this, we hook into the SCTLR_EL1 trapping code, and scan the stage-2 page tables, invalidating the pages/sections that have already been mapped in. Signed-off-by: Marc Zyngier Reviewed-by: Catalin Marinas Reviewed-by: Christoffer Dall --- arch/arm/include/asm/kvm_mmu.h | 2 + arch/arm/kvm/mmu.c | 93 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 95 insertions(+) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index 891afe78311a..eb85b81eea6f 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -155,6 +155,8 @@ static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva, #define kvm_flush_dcache_to_poc(a,l) __cpuc_flush_dcache_area((a), (l)) #define kvm_virt_to_phys(x) virt_to_idmap((unsigned long)(x)) +void stage2_flush_vm(struct kvm *kvm); + #endif /* !__ASSEMBLY__ */ #endif /* __ARM_KVM_MMU_H__ */ diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index c1c08b240f35..d7e998c6a08f 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -187,6 +187,99 @@ static void unmap_range(struct kvm *kvm, pgd_t *pgdp, } } +static void stage2_flush_ptes(struct kvm *kvm, pmd_t *pmd, + phys_addr_t addr, phys_addr_t end) +{ + pte_t *pte; + + pte = pte_offset_kernel(pmd, addr); + do { + if (!pte_none(*pte)) { + hva_t hva = gfn_to_hva(kvm, addr >> PAGE_SHIFT); + kvm_flush_dcache_to_poc((void*)hva, PAGE_SIZE); + } + } while (pte++, addr += PAGE_SIZE, addr != end); +} + +static void stage2_flush_pmds(struct kvm *kvm, pud_t *pud, + phys_addr_t addr, phys_addr_t end) +{ + pmd_t *pmd; + phys_addr_t next; + + pmd = pmd_offset(pud, addr); + do { + next = kvm_pmd_addr_end(addr, end); + if (!pmd_none(*pmd)) { + if (kvm_pmd_huge(*pmd)) { + hva_t hva = gfn_to_hva(kvm, addr >> PAGE_SHIFT); + kvm_flush_dcache_to_poc((void*)hva, PMD_SIZE); + } else { + stage2_flush_ptes(kvm, pmd, addr, next); + } + } + } while (pmd++, addr = next, addr != end); +} + +static void stage2_flush_puds(struct kvm *kvm, pgd_t *pgd, + phys_addr_t addr, phys_addr_t end) +{ + pud_t *pud; + phys_addr_t next; + + pud = pud_offset(pgd, addr); + do { + next = kvm_pud_addr_end(addr, end); + if (!pud_none(*pud)) { + if (pud_huge(*pud)) { + hva_t hva = gfn_to_hva(kvm, addr >> PAGE_SHIFT); + kvm_flush_dcache_to_poc((void*)hva, PUD_SIZE); + } else { + stage2_flush_pmds(kvm, pud, addr, next); + } + } + } while (pud++, addr = next, addr != end); +} + +static void stage2_flush_memslot(struct kvm *kvm, + struct kvm_memory_slot *memslot) +{ + phys_addr_t addr = memslot->base_gfn << PAGE_SHIFT; + phys_addr_t end = addr + PAGE_SIZE * memslot->npages; + phys_addr_t next; + pgd_t *pgd; + + pgd = kvm->arch.pgd + pgd_index(addr); + do { + next = kvm_pgd_addr_end(addr, end); + stage2_flush_puds(kvm, pgd, addr, next); + } while (pgd++, addr = next, addr != end); +} + +/** + * stage2_flush_vm - Invalidate cache for pages mapped in stage 2 + * @kvm: The struct kvm pointer + * + * Go through the stage 2 page tables and invalidate any cache lines + * backing memory already mapped to the VM. + */ +void stage2_flush_vm(struct kvm *kvm) +{ + struct kvm_memslots *slots; + struct kvm_memory_slot *memslot; + int idx; + + idx = srcu_read_lock(&kvm->srcu); + spin_lock(&kvm->mmu_lock); + + slots = kvm_memslots(kvm); + kvm_for_each_memslot(memslot, slots) + stage2_flush_memslot(kvm, memslot); + + spin_unlock(&kvm->mmu_lock); + srcu_read_unlock(&kvm->srcu, idx); +} + /** * free_boot_hyp_pgd - free HYP boot page tables * -- cgit v1.2.3 From 159793001d7d85af17855630c94f0a176848e16b Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 14 Jan 2014 19:13:10 +0000 Subject: ARM: KVM: force cache clean on page fault when caches are off In order for a guest with caches disabled 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_cache_guest_page function and flush the region if the guest SCTLR register doesn't show the MMU and caches as being enabled. Signed-off-by: Marc Zyngier Reviewed-by: Christoffer Dall Reviewed-by: Catalin Marinas --- arch/arm/include/asm/kvm_mmu.h | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index eb85b81eea6f..5c7aa3c1519f 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -129,9 +129,19 @@ static inline void kvm_set_s2pmd_writable(pmd_t *pmd) struct kvm; +#define kvm_flush_dcache_to_poc(a,l) __cpuc_flush_dcache_area((a), (l)) + +static inline bool vcpu_has_cache_enabled(struct kvm_vcpu *vcpu) +{ + return (vcpu->arch.cp15[c1_SCTLR] & 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 we are going to insert an instruction page and the icache is * either VIPT or PIPT, there is a potential problem where the host @@ -152,7 +162,6 @@ static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva, } } -#define kvm_flush_dcache_to_poc(a,l) __cpuc_flush_dcache_area((a), (l)) #define kvm_virt_to_phys(x) virt_to_idmap((unsigned long)(x)) void stage2_flush_vm(struct kvm *kvm); -- cgit v1.2.3 From 46c214dd595381c880794413facadfa07fba5c95 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 21 Jan 2014 18:56:26 +0000 Subject: ARM: KVM: fix handling of trapped 64bit coprocessor accesses Commit 240e99cbd00a (ARM: KVM: Fix 64-bit coprocessor handling) changed the way we match the 64bit coprocessor access from user space, but didn't update the trap handler for the same set of registers. The effect is that a trapped 64bit access is never matched, leading to a fault being injected into the guest. This went unnoticed as we didn't really trap any 64bit register so far. Placing the CRm field of the access into the CRn field of the matching structure fixes the problem. Also update the debug feature to emit the expected string in case of failing match. Signed-off-by: Marc Zyngier Reviewed-by: Christoffer Dall Acked-by: Catalin Marinas --- arch/arm/kvm/coproc.c | 4 ++-- arch/arm/kvm/coproc.h | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c index 78c0885d6501..126c90d18387 100644 --- a/arch/arm/kvm/coproc.c +++ b/arch/arm/kvm/coproc.c @@ -443,7 +443,7 @@ int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run) { struct coproc_params params; - params.CRm = (kvm_vcpu_get_hsr(vcpu) >> 1) & 0xf; + params.CRn = (kvm_vcpu_get_hsr(vcpu) >> 1) & 0xf; params.Rt1 = (kvm_vcpu_get_hsr(vcpu) >> 5) & 0xf; params.is_write = ((kvm_vcpu_get_hsr(vcpu) & 1) == 0); params.is_64bit = true; @@ -451,7 +451,7 @@ int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run) params.Op1 = (kvm_vcpu_get_hsr(vcpu) >> 16) & 0xf; params.Op2 = 0; params.Rt2 = (kvm_vcpu_get_hsr(vcpu) >> 10) & 0xf; - params.CRn = 0; + params.CRm = 0; return emulate_cp15(vcpu, ¶ms); } diff --git a/arch/arm/kvm/coproc.h b/arch/arm/kvm/coproc.h index 0461d5c8d3de..c5ad7ff40c96 100644 --- a/arch/arm/kvm/coproc.h +++ b/arch/arm/kvm/coproc.h @@ -58,8 +58,8 @@ static inline void print_cp_instr(const struct coproc_params *p) { /* Look, we even formatted it for you to paste into the table! */ if (p->is_64bit) { - kvm_pr_unimpl(" { CRm(%2lu), Op1(%2lu), is64, func_%s },\n", - p->CRm, p->Op1, p->is_write ? "write" : "read"); + kvm_pr_unimpl(" { CRm64(%2lu), Op1(%2lu), is64, func_%s },\n", + p->CRn, p->Op1, p->is_write ? "write" : "read"); } else { kvm_pr_unimpl(" { CRn(%2lu), CRm(%2lu), Op1(%2lu), Op2(%2lu), is32," " func_%s },\n", -- cgit v1.2.3 From 547f781378a22b65c2ab468f235c23001b5924da Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 21 Jan 2014 18:56:26 +0000 Subject: ARM: KVM: fix ordering of 64bit coprocessor accesses Commit 240e99cbd00a (ARM: KVM: Fix 64-bit coprocessor handling) added an ordering dependency for the 64bit registers. The order described is: CRn, CRm, Op1, Op2, 64bit-first. Unfortunately, the implementation is: CRn, 64bit-first, CRm... Move the 64bit test to be last in order to match the documentation. Signed-off-by: Marc Zyngier Reviewed-by: Christoffer Dall Acked-by: Catalin Marinas --- arch/arm/kvm/coproc.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/kvm/coproc.h b/arch/arm/kvm/coproc.h index c5ad7ff40c96..8dda870e84f9 100644 --- a/arch/arm/kvm/coproc.h +++ b/arch/arm/kvm/coproc.h @@ -135,13 +135,13 @@ static inline int cmp_reg(const struct coproc_reg *i1, return -1; if (i1->CRn != i2->CRn) return i1->CRn - i2->CRn; - if (i1->is_64 != i2->is_64) - return i2->is_64 - i1->is_64; if (i1->CRm != i2->CRm) return i1->CRm - i2->CRm; if (i1->Op1 != i2->Op1) return i1->Op1 - i2->Op1; - return i1->Op2 - i2->Op2; + if (i1->Op2 != i2->Op2) + return i1->Op2 - i2->Op2; + return i2->is_64 - i1->is_64; } -- cgit v1.2.3 From ac30a11e8e92a03dbe236b285c5cbae0bf563141 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 22 Jan 2014 09:43:38 +0000 Subject: ARM: KVM: introduce per-vcpu HYP Configuration Register So far, KVM/ARM used a fixed HCR configuration per guest, except for the VI/VF/VA bits to control the interrupt in absence of VGIC. With the upcoming need to dynamically reconfigure trapping, it becomes necessary to allow the HCR to be changed on a per-vcpu basis. The fix here is to mimic what KVM/arm64 already does: a per vcpu HCR field, initialized at setup time. Signed-off-by: Marc Zyngier Reviewed-by: Christoffer Dall Acked-by: Catalin Marinas --- arch/arm/include/asm/kvm_arm.h | 1 - arch/arm/include/asm/kvm_host.h | 9 ++++++--- arch/arm/kernel/asm-offsets.c | 1 + arch/arm/kvm/guest.c | 1 + arch/arm/kvm/interrupts_head.S | 9 +++------ 5 files changed, 11 insertions(+), 10 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h index 1d3153c7eb41..a843e74a384c 100644 --- a/arch/arm/include/asm/kvm_arm.h +++ b/arch/arm/include/asm/kvm_arm.h @@ -69,7 +69,6 @@ #define HCR_GUEST_MASK (HCR_TSC | HCR_TSW | HCR_TWI | HCR_VM | HCR_BSU_IS | \ HCR_FB | HCR_TAC | HCR_AMO | HCR_IMO | HCR_FMO | \ HCR_TWE | HCR_SWIO | HCR_TIDCP) -#define HCR_VIRT_EXCP_MASK (HCR_VA | HCR_VI | HCR_VF) /* System Control Register (SCTLR) bits */ #define SCTLR_TE (1 << 30) diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 098f7dd6d564..09af14999c9b 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -101,6 +101,12 @@ struct kvm_vcpu_arch { /* The CPU type we expose to the VM */ u32 midr; + /* HYP trapping configuration */ + u32 hcr; + + /* Interrupt related fields */ + u32 irq_lines; /* IRQ and FIQ levels */ + /* Exception Information */ struct kvm_vcpu_fault_info fault; @@ -128,9 +134,6 @@ struct kvm_vcpu_arch { /* IO related fields */ struct kvm_decode mmio_decode; - /* Interrupt related fields */ - u32 irq_lines; /* IRQ and FIQ levels */ - /* Cache some mmu pages needed inside spinlock regions */ struct kvm_mmu_memory_cache mmu_page_cache; diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c index ded041711beb..85598b5d1efd 100644 --- a/arch/arm/kernel/asm-offsets.c +++ b/arch/arm/kernel/asm-offsets.c @@ -174,6 +174,7 @@ int main(void) DEFINE(VCPU_FIQ_REGS, offsetof(struct kvm_vcpu, arch.regs.fiq_regs)); DEFINE(VCPU_PC, offsetof(struct kvm_vcpu, arch.regs.usr_regs.ARM_pc)); DEFINE(VCPU_CPSR, offsetof(struct kvm_vcpu, arch.regs.usr_regs.ARM_cpsr)); + DEFINE(VCPU_HCR, offsetof(struct kvm_vcpu, arch.hcr)); DEFINE(VCPU_IRQ_LINES, offsetof(struct kvm_vcpu, arch.irq_lines)); DEFINE(VCPU_HSR, offsetof(struct kvm_vcpu, arch.fault.hsr)); DEFINE(VCPU_HxFAR, offsetof(struct kvm_vcpu, arch.fault.hxfar)); diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c index 2786eae10c0d..b23a59c1c522 100644 --- a/arch/arm/kvm/guest.c +++ b/arch/arm/kvm/guest.c @@ -38,6 +38,7 @@ struct kvm_stats_debugfs_item debugfs_entries[] = { int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu) { + vcpu->arch.hcr = HCR_GUEST_MASK; return 0; } diff --git a/arch/arm/kvm/interrupts_head.S b/arch/arm/kvm/interrupts_head.S index 6f18695a09cb..a37270d7d4d6 100644 --- a/arch/arm/kvm/interrupts_head.S +++ b/arch/arm/kvm/interrupts_head.S @@ -597,17 +597,14 @@ vcpu .req r0 @ vcpu pointer always in r0 /* Enable/Disable: stage-2 trans., trap interrupts, trap wfi, trap smc */ .macro configure_hyp_role operation - mrc p15, 4, r2, c1, c1, 0 @ HCR - bic r2, r2, #HCR_VIRT_EXCP_MASK - ldr r3, =HCR_GUEST_MASK .if \operation == vmentry - orr r2, r2, r3 + ldr r2, [vcpu, #VCPU_HCR] ldr r3, [vcpu, #VCPU_IRQ_LINES] orr r2, r2, r3 .else - bic r2, r2, r3 + mov r2, #0 .endif - mcr p15, 4, r2, c1, c1, 0 + mcr p15, 4, r2, c1, c1, 0 @ HCR .endm .macro load_vcpu -- cgit v1.2.3 From af20814ee927ed888288d98917a766b4179c4fe0 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Wed, 22 Jan 2014 10:20:09 +0000 Subject: ARM: KVM: add world-switch for AMAIR{0,1} HCR.TVM traps (among other things) accesses to AMAIR0 and AMAIR1. In order to minimise the amount of surprise a guest could generate by trying to access these registers with caches off, add them to the list of registers we switch/handle. Signed-off-by: Marc Zyngier Reviewed-by: Christoffer Dall Acked-by: Catalin Marinas --- arch/arm/include/asm/kvm_asm.h | 4 +++- arch/arm/kvm/coproc.c | 6 ++++++ arch/arm/kvm/interrupts_head.S | 12 ++++++++++-- 3 files changed, 19 insertions(+), 3 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/kvm_asm.h b/arch/arm/include/asm/kvm_asm.h index 661da11f76f4..53b3c4a50d5c 100644 --- a/arch/arm/include/asm/kvm_asm.h +++ b/arch/arm/include/asm/kvm_asm.h @@ -48,7 +48,9 @@ #define c13_TID_URO 26 /* Thread ID, User R/O */ #define c13_TID_PRIV 27 /* Thread ID, Privileged */ #define c14_CNTKCTL 28 /* Timer Control Register (PL1) */ -#define NR_CP15_REGS 29 /* Number of regs (incl. invalid) */ +#define c10_AMAIR0 29 /* Auxilary Memory Attribute Indirection Reg0 */ +#define c10_AMAIR1 30 /* Auxilary Memory Attribute Indirection Reg1 */ +#define NR_CP15_REGS 31 /* Number of regs (incl. invalid) */ #define ARM_EXCEPTION_RESET 0 #define ARM_EXCEPTION_UNDEFINED 1 diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c index 126c90d18387..a5a54a48d51b 100644 --- a/arch/arm/kvm/coproc.c +++ b/arch/arm/kvm/coproc.c @@ -328,6 +328,12 @@ static const struct coproc_reg cp15_regs[] = { { CRn(10), CRm( 2), Op1( 0), Op2( 1), is32, NULL, reset_unknown, c10_NMRR}, + /* AMAIR0/AMAIR1: swapped by interrupt.S. */ + { CRn(10), CRm( 3), Op1( 0), Op2( 0), is32, + access_vm_reg, reset_unknown, c10_AMAIR0}, + { CRn(10), CRm( 3), Op1( 0), Op2( 1), is32, + access_vm_reg, reset_unknown, c10_AMAIR1}, + /* VBAR: swapped by interrupt.S. */ { CRn(12), CRm( 0), Op1( 0), Op2( 0), is32, NULL, reset_val, c12_VBAR, 0x00000000 }, diff --git a/arch/arm/kvm/interrupts_head.S b/arch/arm/kvm/interrupts_head.S index a37270d7d4d6..76af93025574 100644 --- a/arch/arm/kvm/interrupts_head.S +++ b/arch/arm/kvm/interrupts_head.S @@ -303,13 +303,17 @@ vcpu .req r0 @ vcpu pointer always in r0 mrc p15, 0, r2, c14, c1, 0 @ CNTKCTL mrrc p15, 0, r4, r5, c7 @ PAR + mrc p15, 0, r6, c10, c3, 0 @ AMAIR0 + mrc p15, 0, r7, c10, c3, 1 @ AMAIR1 .if \store_to_vcpu == 0 - push {r2,r4-r5} + push {r2,r4-r7} .else str r2, [vcpu, #CP15_OFFSET(c14_CNTKCTL)] add r12, vcpu, #CP15_OFFSET(c7_PAR) strd r4, r5, [r12] + str r6, [vcpu, #CP15_OFFSET(c10_AMAIR0)] + str r7, [vcpu, #CP15_OFFSET(c10_AMAIR1)] .endif .endm @@ -322,15 +326,19 @@ vcpu .req r0 @ vcpu pointer always in r0 */ .macro write_cp15_state read_from_vcpu .if \read_from_vcpu == 0 - pop {r2,r4-r5} + pop {r2,r4-r7} .else ldr r2, [vcpu, #CP15_OFFSET(c14_CNTKCTL)] add r12, vcpu, #CP15_OFFSET(c7_PAR) ldrd r4, r5, [r12] + ldr r6, [vcpu, #CP15_OFFSET(c10_AMAIR0)] + ldr r7, [vcpu, #CP15_OFFSET(c10_AMAIR1)] .endif mcr p15, 0, r2, c14, c1, 0 @ CNTKCTL mcrr p15, 0, r4, r5, c7 @ PAR + mcr p15, 0, r6, c10, c3, 0 @ AMAIR0 + mcr p15, 0, r7, c10, c3, 1 @ AMAIR1 .if \read_from_vcpu == 0 pop {r2-r12} -- cgit v1.2.3 From 8034699a42d68043b495c7e0cfafccd920707ec8 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 14 Jan 2014 18:00:55 +0000 Subject: ARM: KVM: trap VM system registers until MMU and caches are ON In order to be able to detect the point where the guest enables its MMU and caches, trap all the VM related system registers. Once we see the guest enabling both the MMU and the caches, we can go back to a saner mode of operation, which is to leave these registers in complete control of the guest. Signed-off-by: Marc Zyngier Acked-by: Catalin Marinas Reviewed-by: Christoffer Dall --- arch/arm/include/asm/kvm_arm.h | 3 +- arch/arm/kvm/coproc.c | 74 +++++++++++++++++++++++++++++++++--------- arch/arm/kvm/coproc.h | 4 +++ arch/arm/kvm/coproc_a15.c | 2 +- arch/arm/kvm/coproc_a7.c | 2 +- 5 files changed, 66 insertions(+), 19 deletions(-) (limited to 'arch/arm') diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h index a843e74a384c..816db0bf2dd8 100644 --- a/arch/arm/include/asm/kvm_arm.h +++ b/arch/arm/include/asm/kvm_arm.h @@ -55,6 +55,7 @@ * The bits we set in HCR: * TAC: Trap ACTLR * TSC: Trap SMC + * TVM: Trap VM ops (until MMU and caches are on) * TSW: Trap cache operations by set/way * TWI: Trap WFI * TWE: Trap WFE @@ -68,7 +69,7 @@ */ #define HCR_GUEST_MASK (HCR_TSC | HCR_TSW | HCR_TWI | HCR_VM | HCR_BSU_IS | \ HCR_FB | HCR_TAC | HCR_AMO | HCR_IMO | HCR_FMO | \ - HCR_TWE | HCR_SWIO | HCR_TIDCP) + HCR_TVM | HCR_TWE | HCR_SWIO | HCR_TIDCP) /* System Control Register (SCTLR) bits */ #define SCTLR_TE (1 << 30) diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c index a5a54a48d51b..c58a35116f63 100644 --- a/arch/arm/kvm/coproc.c +++ b/arch/arm/kvm/coproc.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #include #include @@ -204,6 +205,44 @@ done: return true; } +/* + * Generic accessor for VM registers. Only called as long as HCR_TVM + * is set. + */ +static bool access_vm_reg(struct kvm_vcpu *vcpu, + const struct coproc_params *p, + const struct coproc_reg *r) +{ + BUG_ON(!p->is_write); + + vcpu->arch.cp15[r->reg] = *vcpu_reg(vcpu, p->Rt1); + if (p->is_64bit) + vcpu->arch.cp15[r->reg + 1] = *vcpu_reg(vcpu, p->Rt2); + + return true; +} + +/* + * SCTLR accessor. Only called as long as HCR_TVM is set. If the + * guest enables the MMU, we stop trapping the VM sys_regs and leave + * it in complete control of the caches. + * + * Used by the cpu-specific code. + */ +bool access_sctlr(struct kvm_vcpu *vcpu, + const struct coproc_params *p, + const struct coproc_reg *r) +{ + access_vm_reg(vcpu, p, r); + + if (vcpu_has_cache_enabled(vcpu)) { /* MMU+Caches enabled? */ + vcpu->arch.hcr &= ~HCR_TVM; + stage2_flush_vm(vcpu->kvm); + } + + return true; +} + /* * We could trap ID_DFR0 and tell the guest we don't support performance * monitoring. Unfortunately the patch to make the kernel check ID_DFR0 was @@ -261,33 +300,36 @@ static const struct coproc_reg cp15_regs[] = { { CRn( 1), CRm( 0), Op1( 0), Op2( 2), is32, NULL, reset_val, c1_CPACR, 0x00000000 }, - /* TTBR0/TTBR1: swapped by interrupt.S. */ - { CRm64( 2), Op1( 0), is64, NULL, reset_unknown64, c2_TTBR0 }, - { CRm64( 2), Op1( 1), is64, NULL, reset_unknown64, c2_TTBR1 }, - - /* TTBCR: swapped by interrupt.S. */ + /* TTBR0/TTBR1/TTBCR: swapped by interrupt.S. */ + { CRm64( 2), Op1( 0), is64, access_vm_reg, reset_unknown64, c2_TTBR0 }, + { CRn(2), CRm( 0), Op1( 0), Op2( 0), is32, + access_vm_reg, reset_unknown, c2_TTBR0 }, + { CRn(2), CRm( 0), Op1( 0), Op2( 1), is32, + access_vm_reg, reset_unknown, c2_TTBR1 }, { CRn( 2), CRm( 0), Op1( 0), Op2( 2), is32, - NULL, reset_val, c2_TTBCR, 0x00000000 }, + access_vm_reg, reset_val, c2_TTBCR, 0x00000000 }, + { CRm64( 2), Op1( 1), is64, access_vm_reg, reset_unknown64, c2_TTBR1 }, + /* DACR: swapped by interrupt.S. */ { CRn( 3), CRm( 0), Op1( 0), Op2( 0), is32, - NULL, reset_unknown, c3_DACR }, + access_vm_reg, reset_unknown, c3_DACR }, /* DFSR/IFSR/ADFSR/AIFSR: swapped by interrupt.S. */ { CRn( 5), CRm( 0), Op1( 0), Op2( 0), is32, - NULL, reset_unknown, c5_DFSR }, + access_vm_reg, reset_unknown, c5_DFSR }, { CRn( 5), CRm( 0), Op1( 0), Op2( 1), is32, - NULL, reset_unknown, c5_IFSR }, + access_vm_reg, reset_unknown, c5_IFSR }, { CRn( 5), CRm( 1), Op1( 0), Op2( 0), is32, - NULL, reset_unknown, c5_ADFSR }, + access_vm_reg, reset_unknown, c5_ADFSR }, { CRn( 5), CRm( 1), Op1( 0), Op2( 1), is32, - NULL, reset_unknown, c5_AIFSR }, + access_vm_reg, reset_unknown, c5_AIFSR }, /* DFAR/IFAR: swapped by interrupt.S. */ { CRn( 6), CRm( 0), Op1( 0), Op2( 0), is32, - NULL, reset_unknown, c6_DFAR }, + access_vm_reg, reset_unknown, c6_DFAR }, { CRn( 6), CRm( 0), Op1( 0), Op2( 2), is32, - NULL, reset_unknown, c6_IFAR }, + access_vm_reg, reset_unknown, c6_IFAR }, /* PAR swapped by interrupt.S */ { CRm64( 7), Op1( 0), is64, NULL, reset_unknown64, c7_PAR }, @@ -324,9 +366,9 @@ static const struct coproc_reg cp15_regs[] = { /* PRRR/NMRR (aka MAIR0/MAIR1): swapped by interrupt.S. */ { CRn(10), CRm( 2), Op1( 0), Op2( 0), is32, - NULL, reset_unknown, c10_PRRR}, + access_vm_reg, reset_unknown, c10_PRRR}, { CRn(10), CRm( 2), Op1( 0), Op2( 1), is32, - NULL, reset_unknown, c10_NMRR}, + access_vm_reg, reset_unknown, c10_NMRR}, /* AMAIR0/AMAIR1: swapped by interrupt.S. */ { CRn(10), CRm( 3), Op1( 0), Op2( 0), is32, @@ -340,7 +382,7 @@ static const struct coproc_reg cp15_regs[] = { /* CONTEXTIDR/TPIDRURW/TPIDRURO/TPIDRPRW: swapped by interrupt.S. */ { CRn(13), CRm( 0), Op1( 0), Op2( 1), is32, - NULL, reset_val, c13_CID, 0x00000000 }, + access_vm_reg, reset_val, c13_CID, 0x00000000 }, { CRn(13), CRm( 0), Op1( 0), Op2( 2), is32, NULL, reset_unknown, c13_TID_URW }, { CRn(13), CRm( 0), Op1( 0), Op2( 3), is32, diff --git a/arch/arm/kvm/coproc.h b/arch/arm/kvm/coproc.h index 8dda870e84f9..1a44bbe39643 100644 --- a/arch/arm/kvm/coproc.h +++ b/arch/arm/kvm/coproc.h @@ -153,4 +153,8 @@ static inline int cmp_reg(const struct coproc_reg *i1, #define is64 .is_64 = true #define is32 .is_64 = false +bool access_sctlr(struct kvm_vcpu *vcpu, + const struct coproc_params *p, + const struct coproc_reg *r); + #endif /* __ARM_KVM_COPROC_LOCAL_H__ */ diff --git a/arch/arm/kvm/coproc_a15.c b/arch/arm/kvm/coproc_a15.c index bb0cac1410cc..e6f4ae48bda9 100644 --- a/arch/arm/kvm/coproc_a15.c +++ b/arch/arm/kvm/coproc_a15.c @@ -34,7 +34,7 @@ static const struct coproc_reg a15_regs[] = { /* SCTLR: swapped by interrupt.S. */ { CRn( 1), CRm( 0), Op1( 0), Op2( 0), is32, - NULL, reset_val, c1_SCTLR, 0x00C50078 }, + access_sctlr, reset_val, c1_SCTLR, 0x00C50078 }, }; static struct kvm_coproc_target_table a15_target_table = { diff --git a/arch/arm/kvm/coproc_a7.c b/arch/arm/kvm/coproc_a7.c index 1df767331588..17fc7cd479d3 100644 --- a/arch/arm/kvm/coproc_a7.c +++ b/arch/arm/kvm/coproc_a7.c @@ -37,7 +37,7 @@ static const struct coproc_reg a7_regs[] = { /* SCTLR: swapped by interrupt.S. */ { CRn( 1), CRm( 0), Op1( 0), Op2( 0), is32, - NULL, reset_val, c1_SCTLR, 0x00C50878 }, + access_sctlr, reset_val, c1_SCTLR, 0x00C50878 }, }; static struct kvm_coproc_target_table a7_target_table = { -- cgit v1.2.3 From 56041bf920d2937b7cadcb30cb206f0372eee814 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 30 Jan 2014 17:38:33 +0000 Subject: ARM: KVM: fix warning in mmu.c MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Compiling with THP enabled leads to the following warning: arch/arm/kvm/mmu.c: In function ‘unmap_range’: arch/arm/kvm/mmu.c:177:39: warning: ‘pte’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (kvm_pmd_huge(*pmd) || page_empty(pte)) { ^ Code inspection reveals that these two cases are mutually exclusive, so GCC is a bit overzealous here. Silence it anyway by initializing pte to NULL and testing it later on. Signed-off-by: Marc Zyngier Acked-by: Christoffer Dall --- arch/arm/kvm/mmu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/arm') diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index d7e998c6a08f..80bb1e6c2c29 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -144,6 +144,7 @@ static void unmap_range(struct kvm *kvm, pgd_t *pgdp, while (addr < end) { pgd = pgdp + pgd_index(addr); pud = pud_offset(pgd, addr); + pte = NULL; if (pud_none(*pud)) { addr = kvm_pud_addr_end(addr, end); continue; @@ -174,7 +175,7 @@ static void unmap_range(struct kvm *kvm, pgd_t *pgdp, /* * If the pmd entry is to be cleared, walk back up the ladder */ - if (kvm_pmd_huge(*pmd) || page_empty(pte)) { + if (kvm_pmd_huge(*pmd) || (pte && page_empty(pte))) { clear_pmd_entry(kvm, pmd, addr); next = kvm_pmd_addr_end(addr, end); if (page_empty(pmd) && !page_empty(pud)) { -- cgit v1.2.3