linux-kernel - [PATCH v2 5/7] x86/irq: Count Hyper-V reenlightenment interrupts

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]

Message-Id: <20171213150945.24054-6-vkuznets@redhat.com>
Date:   Wed, 13 Dec 2017 16:09:43 +0100
From:   Vitaly Kuznetsov <vkuznets@...hat.com>
To:     kvm@...r.kernel.org, x86@...nel.org
Cc:     Paolo Bonzini <pbonzini@...hat.com>,
        Radim Krčmář <rkrcmar@...hat.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        "H. Peter Anvin" <hpa@...or.com>,
        "K. Y. Srinivasan" <kys@...rosoft.com>,
        Haiyang Zhang <haiyangz@...rosoft.com>,
        Stephen Hemminger <sthemmin@...rosoft.com>,
        "Michael Kelley (EOSG)" <Michael.H.Kelley@...rosoft.com>,
        Andy Lutomirski <luto@...nel.org>,
        Mohammed Gamal <mmorsy@...hat.com>,
        Cathy Avery <cavery@...hat.com>,
        Roman Kagan <rkagan@...tuozzo.com>,
        linux-kernel@...r.kernel.org, devel@...uxdriverproject.org
Subject: [PATCH v2 5/7] x86/irq: Count Hyper-V reenlightenment interrupts

Hyper-V reenlightenment interrupts arrive when the VM is migrated, we're
not supposed to see many of them. However, it may be important to know
that the event has happened in case we have L2 nested guests.

Signed-off-by: Vitaly Kuznetsov <vkuznets@...hat.com>
---
 arch/x86/hyperv/hv_init.c      | 2 ++
 arch/x86/include/asm/hardirq.h | 3 +++
 arch/x86/kernel/irq.c          | 9 +++++++++
 3 files changed, 14 insertions(+)

diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index 38118ca38d97..6b59386746f5 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -147,6 +147,8 @@ void hyperv_reenlightenment_intr(struct pt_regs *regs)
 {
 	entering_ack_irq();
 
+	inc_irq_stat(irq_hv_reenlightenment_count);
+
 	schedule_delayed_work(&hv_reenlightenment_work, HZ/10);
 
 	exiting_irq();
diff --git a/arch/x86/include/asm/hardirq.h b/arch/x86/include/asm/hardirq.h
index 51cc979dd364..7c341a74ec8c 100644
--- a/arch/x86/include/asm/hardirq.h
+++ b/arch/x86/include/asm/hardirq.h
@@ -38,6 +38,9 @@ typedef struct {
 #if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
 	unsigned int irq_hv_callback_count;
 #endif
+#if IS_ENABLED(CONFIG_HYPERV)
+	unsigned int irq_hv_reenlightenment_count;
+#endif
 } ____cacheline_aligned irq_cpustat_t;
 
 DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 49cfd9fe7589..8aac86b5c4d8 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -141,6 +141,15 @@ int arch_show_interrupts(struct seq_file *p, int prec)
 				   irq_stats(j)->irq_hv_callback_count);
 		seq_puts(p, "  Hypervisor callback interrupts\n");
 	}
+#endif
+#if IS_ENABLED(CONFIG_HYPERV)
+	if (test_bit(HYPERV_REENLIGHTENMENT_VECTOR, system_vectors)) {
+		seq_printf(p, "%*s: ", prec, "HRE");
+		for_each_online_cpu(j)
+			seq_printf(p, "%10u ",
+				   irq_stats(j)->irq_hv_reenlightenment_count);
+		seq_puts(p, "  Hyper-V reenlightenment interrupts\n");
+	}
 #endif
 	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
 #if defined(CONFIG_X86_IO_APIC)
-- 
2.14.3