linux-kernel - [RFC PATCH v2 3/7] x86/kvm, ptp/kvm: Add clocksource ID, set system_counterval_t.cs

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20231215220612.173603-4-peter.hilber@opensynergy.com>
Date: Fri, 15 Dec 2023 23:06:08 +0100
From: Peter Hilber <peter.hilber@...nsynergy.com>
To: linux-kernel@...r.kernel.org
Cc: Peter Hilber <peter.hilber@...nsynergy.com>,
	"D, Lakshmi Sowjanya" <lakshmi.sowjanya.d@...el.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	jstultz@...gle.com,
	giometti@...eenne.com,
	corbet@....net,
	andriy.shevchenko@...ux.intel.com,
	"Dong, Eddie" <eddie.dong@...el.com>,
	"Hall, Christopher S" <christopher.s.hall@...el.com>,
	Marc Zyngier <maz@...nel.org>,
	linux-arm-kernel@...ts.infradead.org,
	Sean Christopherson <seanjc@...gle.com>,
	Paolo Bonzini <pbonzini@...hat.com>,
	Ingo Molnar <mingo@...hat.com>,
	Borislav Petkov <bp@...en8.de>,
	Dave Hansen <dave.hansen@...ux.intel.com>,
	x86@...nel.org,
	"H. Peter Anvin" <hpa@...or.com>,
	Wanpeng Li <wanpengli@...cent.com>,
	Vitaly Kuznetsov <vkuznets@...hat.com>,
	Mark Rutland <mark.rutland@....com>,
	Daniel Lezcano <daniel.lezcano@...aro.org>,
	Richard Cochran <richardcochran@...il.com>,
	kvm@...r.kernel.org,
	netdev@...r.kernel.org
Subject: [RFC PATCH v2 3/7] x86/kvm, ptp/kvm: Add clocksource ID, set system_counterval_t.cs_id

Add a clocksource ID for the x86 kvmclock.

Also, for ptp_kvm, set the recently added struct system_counterval_t member
cs_id to the clocksource ID (x86 kvmclock or Arm Generic Timer). In the
future, this will keep get_device_system_crosststamp() working, when it
will compare the clocksource id in struct system_counterval_t, rather than
the clocksource.

For now, to avoid touching too many subsystems at once, extract the
clocksource ID from the clocksource. The clocksource dereference will be
removed in the following.

Signed-off-by: Peter Hilber <peter.hilber@...nsynergy.com>
---

Notes:
    v2:
    
    - Name clock id according to Thomas Gleixner's mockup.

 arch/x86/kernel/kvmclock.c      | 2 ++
 drivers/ptp/ptp_kvm_common.c    | 2 ++
 include/linux/clocksource_ids.h | 1 +
 3 files changed, 5 insertions(+)

diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c
index fb8f52149be9..25d6bf743b03 100644
--- a/arch/x86/kernel/kvmclock.c
+++ b/arch/x86/kernel/kvmclock.c
@@ -4,6 +4,7 @@
 */
 
 #include <linux/clocksource.h>
+#include <linux/clocksource_ids.h>
 #include <linux/kvm_para.h>
 #include <asm/pvclock.h>
 #include <asm/msr.h>
@@ -160,6 +161,7 @@ struct clocksource kvm_clock = {
 	.rating	= 400,
 	.mask	= CLOCKSOURCE_MASK(64),
 	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
+	.id     = CSID_X86_KVM_CLK,
 	.enable	= kvm_cs_enable,
 };
 EXPORT_SYMBOL_GPL(kvm_clock);
diff --git a/drivers/ptp/ptp_kvm_common.c b/drivers/ptp/ptp_kvm_common.c
index 2418977989be..b0b36f135347 100644
--- a/drivers/ptp/ptp_kvm_common.c
+++ b/drivers/ptp/ptp_kvm_common.c
@@ -4,6 +4,7 @@
  *
  * Copyright (C) 2017 Red Hat Inc.
  */
+#include <linux/clocksource.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/init.h>
@@ -47,6 +48,7 @@ static int ptp_kvm_get_time_fn(ktime_t *device_time,
 
 	system_counter->cycles = cycle;
 	system_counter->cs = cs;
+	system_counter->cs_id = cs->id;
 
 	*device_time = timespec64_to_ktime(tspec);
 
diff --git a/include/linux/clocksource_ids.h b/include/linux/clocksource_ids.h
index f8467946e9ee..a4fa3436940c 100644
--- a/include/linux/clocksource_ids.h
+++ b/include/linux/clocksource_ids.h
@@ -8,6 +8,7 @@ enum clocksource_ids {
 	CSID_ARM_ARCH_COUNTER,
 	CSID_X86_TSC_EARLY,
 	CSID_X86_TSC,
+	CSID_X86_KVM_CLK,
 	CSID_MAX,
 };
 
-- 
2.40.1