lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Sat, 13 Feb 2010 10:01:53 +0200
From:	Avi Kivity <avi@...hat.com>
To:	kvm@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org
Subject: [PATCH 33/39] KVM: PPC: Keep SRR1 flags around in shadow_msr

From: Alexander Graf <agraf@...e.de>

SRR1 stores more information that just the MSR value. It also stores
valuable information about the type of interrupt we received, for
example whether the storage interrupt we just got was because of a
missing htab entry or not.

We use that information to speed up the exit path.

Now if we get preempted before we can interpret the shadow_msr values,
we get into vcpu_put which then calls the MSR handler, which then sets
all the SRR1 information bits in shadow_msr to 0. Great.

So let's preserve the SRR1 specific bits in shadow_msr whenever we set
the MSR. They don't hurt.

Signed-off-by: Alexander Graf <agraf@...e.de>
Signed-off-by: Avi Kivity <avi@...hat.com>
---
 arch/powerpc/include/asm/kvm_host.h     |    1 +
 arch/powerpc/kernel/asm-offsets.c       |    1 +
 arch/powerpc/kvm/book3s.c               |   13 +++++++------
 arch/powerpc/kvm/book3s_64_interrupts.S |    2 +-
 4 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index c30a70c..715aa6b 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -198,6 +198,7 @@ struct kvm_vcpu_arch {
 	ulong msr;
 #ifdef CONFIG_PPC64
 	ulong shadow_msr;
+	ulong shadow_srr1;
 	ulong hflags;
 	ulong guest_owned_ext;
 #endif
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index ee99354..957ceb7 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -433,6 +433,7 @@ int main(void)
 	DEFINE(VCPU_HOST_R2, offsetof(struct kvm_vcpu, arch.host_r2));
 	DEFINE(VCPU_HOST_MSR, offsetof(struct kvm_vcpu, arch.host_msr));
 	DEFINE(VCPU_SHADOW_MSR, offsetof(struct kvm_vcpu, arch.shadow_msr));
+	DEFINE(VCPU_SHADOW_SRR1, offsetof(struct kvm_vcpu, arch.shadow_srr1));
 	DEFINE(VCPU_TRAMPOLINE_LOWMEM, offsetof(struct kvm_vcpu, arch.trampoline_lowmem));
 	DEFINE(VCPU_TRAMPOLINE_ENTER, offsetof(struct kvm_vcpu, arch.trampoline_enter));
 	DEFINE(VCPU_HIGHMEM_HANDLER, offsetof(struct kvm_vcpu, arch.highmem_handler));
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 2cb1813..58f5200 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -524,14 +524,14 @@ int kvmppc_handle_pagefault(struct kvm_run *run, struct kvm_vcpu *vcpu,
 		/* Page not found in guest PTE entries */
 		vcpu->arch.dear = vcpu->arch.fault_dear;
 		to_book3s(vcpu)->dsisr = vcpu->arch.fault_dsisr;
-		vcpu->arch.msr |= (vcpu->arch.shadow_msr & 0x00000000f8000000ULL);
+		vcpu->arch.msr |= (vcpu->arch.shadow_srr1 & 0x00000000f8000000ULL);
 		kvmppc_book3s_queue_irqprio(vcpu, vec);
 	} else if (page_found == -EPERM) {
 		/* Storage protection */
 		vcpu->arch.dear = vcpu->arch.fault_dear;
 		to_book3s(vcpu)->dsisr = vcpu->arch.fault_dsisr & ~DSISR_NOHPTE;
 		to_book3s(vcpu)->dsisr |= DSISR_PROTFAULT;
-		vcpu->arch.msr |= (vcpu->arch.shadow_msr & 0x00000000f8000000ULL);
+		vcpu->arch.msr |= (vcpu->arch.shadow_srr1 & 0x00000000f8000000ULL);
 		kvmppc_book3s_queue_irqprio(vcpu, vec);
 	} else if (page_found == -EINVAL) {
 		/* Page not found in guest SLB */
@@ -693,7 +693,7 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
 	case BOOK3S_INTERRUPT_INST_STORAGE:
 		vcpu->stat.pf_instruc++;
 		/* only care about PTEG not found errors, but leave NX alone */
-		if (vcpu->arch.shadow_msr & 0x40000000) {
+		if (vcpu->arch.shadow_srr1 & 0x40000000) {
 			r = kvmppc_handle_pagefault(run, vcpu, vcpu->arch.pc, exit_nr);
 			vcpu->stat.sp_instruc++;
 		} else if (vcpu->arch.mmu.is_dcbz32(vcpu) &&
@@ -705,7 +705,7 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
 			 */
 			kvmppc_mmu_pte_flush(vcpu, vcpu->arch.pc, ~0xFFFULL);
 		} else {
-			vcpu->arch.msr |= (vcpu->arch.shadow_msr & 0x58000000);
+			vcpu->arch.msr |= vcpu->arch.shadow_srr1 & 0x58000000;
 			kvmppc_book3s_queue_irqprio(vcpu, exit_nr);
 			kvmppc_mmu_pte_flush(vcpu, vcpu->arch.pc, ~0xFFFULL);
 			r = RESUME_GUEST;
@@ -753,7 +753,7 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
 		enum emulation_result er;
 		ulong flags;
 
-		flags = (vcpu->arch.shadow_msr & 0x1f0000ull);
+		flags = vcpu->arch.shadow_srr1 & 0x1f0000ull;
 
 		if (vcpu->arch.msr & MSR_PR) {
 #ifdef EXIT_DEBUG
@@ -808,7 +808,8 @@ int kvmppc_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu,
 		break;
 	default:
 		/* Ugh - bork here! What did we get? */
-		printk(KERN_EMERG "exit_nr=0x%x | pc=0x%lx | msr=0x%lx\n", exit_nr, vcpu->arch.pc, vcpu->arch.shadow_msr);
+		printk(KERN_EMERG "exit_nr=0x%x | pc=0x%lx | msr=0x%lx\n",
+			exit_nr, vcpu->arch.pc, vcpu->arch.shadow_srr1);
 		r = RESUME_HOST;
 		BUG();
 		break;
diff --git a/arch/powerpc/kvm/book3s_64_interrupts.S b/arch/powerpc/kvm/book3s_64_interrupts.S
index 2ff0b21..c1584d0 100644
--- a/arch/powerpc/kvm/book3s_64_interrupts.S
+++ b/arch/powerpc/kvm/book3s_64_interrupts.S
@@ -169,7 +169,7 @@ kvmppc_handler_highmem:
 	stw	r0, VCPU_LAST_INST(r7)
 
 	std	r3, VCPU_PC(r7)
-	std	r4, VCPU_SHADOW_MSR(r7)
+	std	r4, VCPU_SHADOW_SRR1(r7)
 	std	r5, VCPU_FAULT_DEAR(r7)
 	std	r6, VCPU_FAULT_DSISR(r7)
 
-- 
1.6.5.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ