[PATCH v2 4/6] KVM: arm/arm64: Reduce verbosity of KVM init log

From: Marc Zyngier <marc.zyngier@arm.com>
To: "Paolo Bonzini" <pbonzini@redhat.com>,
	"Radim Krčmář" <rkrcmar@redhat.com>
Cc: kvm@vger.kernel.org, Ard Biesheuvel <ard.biesheuvel@linaro.org>,
	Andre Przywara <andre.przywara@arm.com>,
	Will Deacon <will.deacon@arm.com>,
	kvmarm@lists.cs.columbia.edu,
	linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2 4/6] KVM: arm/arm64: Reduce verbosity of KVM init log
Date: Thu, 15 Mar 2018 17:16:46 +0000	[thread overview]
Message-ID: <20180315171648.19501-5-marc.zyngier@arm.com> (raw)
In-Reply-To: <20180315171648.19501-1-marc.zyngier@arm.com>

From: Ard Biesheuvel <ard.biesheuvel@linaro.org>

On my GICv3 system, the following is printed to the kernel log at boot:

   kvm [1]: 8-bit VMID
   kvm [1]: IDMAP page: d20e35000
   kvm [1]: HYP VA range: 800000000000:ffffffffffff
   kvm [1]: vgic-v2@2c020000
   kvm [1]: GIC system register CPU interface enabled
   kvm [1]: vgic interrupt IRQ1
   kvm [1]: virtual timer IRQ4
   kvm [1]: Hyp mode initialized successfully

The KVM IDMAP is a mapping of a statically allocated kernel structure,
and so printing its physical address leaks the physical placement of
the kernel when physical KASLR in effect. So change the kvm_info() to
kvm_debug() to remove it from the log output.

While at it, trim the output a bit more: IRQ numbers can be found in
/proc/interrupts, and the HYP VA and vgic-v2 lines are not highly
informational either.

Cc: <stable@vger.kernel.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Christoffer Dall <cdall@kernel.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 virt/kvm/arm/arch_timer.c   | 2 +-
 virt/kvm/arm/mmu.c          | 6 +++---
 virt/kvm/arm/vgic/vgic-v2.c | 2 +-
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
index 3945021510a9..282389eb204f 100644
--- a/virt/kvm/arm/arch_timer.c
+++ b/virt/kvm/arm/arch_timer.c
@@ -771,7 +771,7 @@ int kvm_timer_hyp_init(bool has_gic)
 		static_branch_enable(&has_gic_active_state);
 	}
 
-	kvm_info("virtual timer IRQ%d\n", host_vtimer_irq);
+	kvm_debug("virtual timer IRQ%d\n", host_vtimer_irq);
 
 	cpuhp_setup_state(CPUHP_AP_KVM_ARM_TIMER_STARTING,
 			  "kvm/arm/timer:starting", kvm_timer_starting_cpu,
diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c
index ec62d1cccab7..b960acdd0c05 100644
--- a/virt/kvm/arm/mmu.c
+++ b/virt/kvm/arm/mmu.c
@@ -1810,9 +1810,9 @@ int kvm_mmu_init(void)
 	 */
 	BUG_ON((hyp_idmap_start ^ (hyp_idmap_end - 1)) & PAGE_MASK);
 
-	kvm_info("IDMAP page: %lx\n", hyp_idmap_start);
-	kvm_info("HYP VA range: %lx:%lx\n",
-		 kern_hyp_va(PAGE_OFFSET), kern_hyp_va(~0UL));
+	kvm_debug("IDMAP page: %lx\n", hyp_idmap_start);
+	kvm_debug("HYP VA range: %lx:%lx\n",
+		  kern_hyp_va(PAGE_OFFSET), kern_hyp_va(~0UL));
 
 	if (hyp_idmap_start >= kern_hyp_va(PAGE_OFFSET) &&
 	    hyp_idmap_start <  kern_hyp_va(~0UL) &&
diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c
index c32d7b93ffd1..e9d840a75e7b 100644
--- a/virt/kvm/arm/vgic/vgic-v2.c
+++ b/virt/kvm/arm/vgic/vgic-v2.c
@@ -410,7 +410,7 @@ int vgic_v2_probe(const struct gic_kvm_info *info)
 	kvm_vgic_global_state.type = VGIC_V2;
 	kvm_vgic_global_state.max_gic_vcpus = VGIC_V2_MAX_CPUS;
 
-	kvm_info("vgic-v2@%llx\n", info->vctrl.start);
+	kvm_debug("vgic-v2@%llx\n", info->vctrl.start);
 
 	return 0;
 out:
-- 
2.14.2
