[PATCH v7 0/3] x86: Add the support of ACRN guest under x86

[PATCH v7 0/3] x86: Add the support of ACRN guest under x86

[Zhao Yakui]

ACRN is a flexible, lightweight reference hypervisor, built with real-time
and safety-criticality in mind, optimized to streamline embedded development
through an open source platform. It is built for embedded IOT with small
footprint and real-time features. More details can be found
in https://projectacrn.org/

This is the patch set that allows the Linux to work on ACRN hypervisor and it can
work with the following patch set to manage the Linux guest on ACRN hypervisor. It
includes the detection of ACRN hypervisor, upcall notification vector from
hypervisor, hypercall. The hypervisor detection is similar to Xen/VMWARE/Hyperv.
ACRN also uses the upcall notification mechanism similar to that in Xen/Microsoft
HyperV when it needs to send the notification to Linux guest. The hypercall provides
the mechanism that can be used to query/configure the ACRN hypervisor by Linux guest.

Following this patch set, we will send acrn driver part, which provides the interface
that can be used to manage the virtualized CPU/memory/device/interrupt for other guest
OS after the ACRN hypervisor is detected.

v1->v2: Change the CONFIG_ACRN to CONFIG_ACRN_GUEST, which makes it easy to
understand.
	Remove the export of x86_hyper_acrn.
	Remove the unused API definition of acrn_setup_intr_handler and
acrn_remove_intr_handler.
        Adjust the order of header file
	Add the declaration of acrn_hv_vector_handler and tracing
definition of acrn_hv_callback_vector.
	Refine the comments for the function of acrn_hypercall0/1/2

v2-v3:  Add one new config symbol to unify the conditional definition
of hv_irq_callback_count
	Use the "vmcall" mnemonic to replace the hard-code byte definition
	Remove the unnecessary dependency of CONFIG_PARAVIRT for ACRN_GUEST

v3-v4:  Rename the file name of acrnhyper.h to acrn.h
	Refine the commit log and some other minor changes(more comments and 
redundant ifdef in acrn.h, sorting the header file in acrn.c)

v4->v5: Minor changes of comments/commit log in patch 04
	Use _ASM_X86_ACRN_HYPERCALL_H instead of _ASM_X86_ACRNHYPERCALL_H.
	Use the "VMCALL" mnemonic in comment/commit log.
	Uppercase r8/rdi/rsi/rax for hypercall parameter register in comment.

v5->v6: Remove the explicit register variable for inline assembly
	Add the "extern" for the function declaration in acrn.h
	Add comments about acking ACPI EOI in acrn_hv_callback_handler
	Minor changes for comments/commit log in patch 03/04

v6->v7: Add the missing header file of asm/apic.h in acrn.c
        Remove the definition of ACRN hypercall as it is not used in this
        patch set.


Zhao Yakui (3):
  x86/Kconfig: Add new config symbol to unify conditional definition of
    hv_irq_callback_count
  x86: Add the support of Linux guest on ACRN hypervisor
  x86/acrn: Use HYPERVISOR_CALLBACK_VECTOR for ACRN guest upcall vector

 arch/x86/Kconfig                  | 16 +++++++++
 arch/x86/entry/entry_64.S         |  5 +++
 arch/x86/include/asm/acrn.h       | 11 +++++++
 arch/x86/include/asm/hardirq.h    |  2 +-
 arch/x86/include/asm/hypervisor.h |  1 +
 arch/x86/kernel/cpu/Makefile      |  1 +
 arch/x86/kernel/cpu/acrn.c        | 69 +++++++++++++++++++++++++++++++++++++++
 arch/x86/kernel/cpu/hypervisor.c  |  4 +++
 arch/x86/kernel/irq.c             |  2 +-
 arch/x86/xen/Kconfig              |  1 +
 drivers/hv/Kconfig                |  1 +
 11 files changed, 111 insertions(+), 2 deletions(-)
 create mode 100644 arch/x86/include/asm/acrn.h
 create mode 100644 arch/x86/kernel/cpu/acrn.c

-- 
2.7.4

[PATCH v7 1/3] x86/Kconfig: Add new config symbol to unify conditional definition of hv_irq_callback_count

[Zhao Yakui]

Add a special Kconfig symbol X86_HV_CALLBACK_VECTOR so that the guests
using the hypervisor interrupt callback counter can select and thus
enable that counter. Select it when xen or hyperv support is enabled.
No functional changes.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
---
v3->v4: Follow the comments to refine the commit log.
---
 arch/x86/Kconfig               | 3 +++
 arch/x86/include/asm/hardirq.h | 2 +-
 arch/x86/kernel/irq.c          | 2 +-
 arch/x86/xen/Kconfig           | 1 +
 drivers/hv/Kconfig             | 1 +
 5 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 2bbbd4d..c9ab090 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -781,6 +781,9 @@ config PARAVIRT_SPINLOCKS
 
 	  If you are unsure how to answer this question, answer Y.
 
+config X86_HV_CALLBACK_VECTOR
+	def_bool n
+
 source "arch/x86/xen/Kconfig"
 
 config KVM_GUEST
diff --git a/arch/x86/include/asm/hardirq.h b/arch/x86/include/asm/hardirq.h
index d9069bb..0753379 100644
--- a/arch/x86/include/asm/hardirq.h
+++ b/arch/x86/include/asm/hardirq.h
@@ -37,7 +37,7 @@ typedef struct {
 #ifdef CONFIG_X86_MCE_AMD
 	unsigned int irq_deferred_error_count;
 #endif
-#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
+#ifdef CONFIG_X86_HV_CALLBACK_VECTOR
 	unsigned int irq_hv_callback_count;
 #endif
 #if IS_ENABLED(CONFIG_HYPERV)
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 9b68b5b..4e8f193 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -135,7 +135,7 @@ int arch_show_interrupts(struct seq_file *p, int prec)
 		seq_printf(p, "%10u ", per_cpu(mce_poll_count, j));
 	seq_puts(p, "  Machine check polls\n");
 #endif
-#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
+#ifdef CONFIG_X86_HV_CALLBACK_VECTOR
 	if (test_bit(HYPERVISOR_CALLBACK_VECTOR, system_vectors)) {
 		seq_printf(p, "%*s: ", prec, "HYP");
 		for_each_online_cpu(j)
diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
index e07abef..ba5a418 100644
--- a/arch/x86/xen/Kconfig
+++ b/arch/x86/xen/Kconfig
@@ -7,6 +7,7 @@ config XEN
 	bool "Xen guest support"
 	depends on PARAVIRT
 	select PARAVIRT_CLOCK
+	select X86_HV_CALLBACK_VECTOR
 	depends on X86_64 || (X86_32 && X86_PAE)
 	depends on X86_LOCAL_APIC && X86_TSC
 	help
diff --git a/drivers/hv/Kconfig b/drivers/hv/Kconfig
index 1c1a251..cafcb97 100644
--- a/drivers/hv/Kconfig
+++ b/drivers/hv/Kconfig
@@ -6,6 +6,7 @@ config HYPERV
 	tristate "Microsoft Hyper-V client drivers"
 	depends on X86 && ACPI && X86_LOCAL_APIC && HYPERVISOR_GUEST
 	select PARAVIRT
+	select X86_HV_CALLBACK_VECTOR
 	help
 	  Select this option to run Linux as a Hyper-V client operating
 	  system.
-- 
2.7.4

[PATCH v7 2/3] x86: Add the support of Linux guest on ACRN hypervisor

[Zhao Yakui]

ACRN is an open-source hypervisor maintained by Linux Foundation.
It is built for embedded IOT with small footprint and real-time features.
Add the ACRN guest support so that it allows linux to be booted under the
ACRN hypervisor. Following this patch it will setup the upcall
notification vector, enable hypercall and provide the interface that is
used to manage the virtualized CPU/memory/device/interrupt for other
guest OS.

Co-developed-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
---
v1->v2: Change the CONFIG_ACRN to CONFIG_ACRN_GUEST, which makes it easy to
understand.
        Remove the export of x86_hyper_acrn.

v2->v3: Remove the unnecessary dependency of PARAVIRT
v3->v4: Refine the commit log and add more meaningful description in Kconfig
v4->v5: No change
v5->v6: No change
v6->v7: No change
---
 arch/x86/Kconfig                  | 12 ++++++++++++
 arch/x86/include/asm/hypervisor.h |  1 +
 arch/x86/kernel/cpu/Makefile      |  1 +
 arch/x86/kernel/cpu/acrn.c        | 39 +++++++++++++++++++++++++++++++++++++++
 arch/x86/kernel/cpu/hypervisor.c  |  4 ++++
 5 files changed, 57 insertions(+)
 create mode 100644 arch/x86/kernel/cpu/acrn.c

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index c9ab090..3020bc7 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -835,6 +835,18 @@ config JAILHOUSE_GUEST
 	  cell. You can leave this option disabled if you only want to start
 	  Jailhouse and run Linux afterwards in the root cell.
 
+config ACRN_GUEST
+	bool "ACRN Guest support"
+	depends on X86_64
+	help
+	  This option allows to run Linux as guest in ACRN hypervisor. Enabling
+	  this will allow the kernel to boot in virtualized environment under
+	  the ACRN hypervisor.
+	  ACRN is a flexible, lightweight reference open-source hypervisor, built
+	  with real-time and safety-criticality in mind. It is built for embedded
+	  IOT with small footprint and real-time features. More details can be
+	  found in https://projectacrn.org/
+
 endif #HYPERVISOR_GUEST
 
 source "arch/x86/Kconfig.cpu"
diff --git a/arch/x86/include/asm/hypervisor.h b/arch/x86/include/asm/hypervisor.h
index 8c5aaba..50a30f6 100644
--- a/arch/x86/include/asm/hypervisor.h
+++ b/arch/x86/include/asm/hypervisor.h
@@ -29,6 +29,7 @@ enum x86_hypervisor_type {
 	X86_HYPER_XEN_HVM,
 	X86_HYPER_KVM,
 	X86_HYPER_JAILHOUSE,
+	X86_HYPER_ACRN,
 };
 
 #ifdef CONFIG_HYPERVISOR_GUEST
diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile
index 1796d2b..b9b3017 100644
--- a/arch/x86/kernel/cpu/Makefile
+++ b/arch/x86/kernel/cpu/Makefile
@@ -44,6 +44,7 @@ obj-$(CONFIG_X86_CPU_RESCTRL)		+= resctrl/
 obj-$(CONFIG_X86_LOCAL_APIC)		+= perfctr-watchdog.o
 
 obj-$(CONFIG_HYPERVISOR_GUEST)		+= vmware.o hypervisor.o mshyperv.o
+obj-$(CONFIG_ACRN_GUEST)		+= acrn.o
 
 ifdef CONFIG_X86_FEATURE_NAMES
 quiet_cmd_mkcapflags = MKCAP   $@
diff --git a/arch/x86/kernel/cpu/acrn.c b/arch/x86/kernel/cpu/acrn.c
new file mode 100644
index 0000000..f556640
--- /dev/null
+++ b/arch/x86/kernel/cpu/acrn.c
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ACRN detection support
+ *
+ * Copyright (C) 2019 Intel Corporation. All rights reserved.
+ *
+ * Jason Chen CJ <jason.cj.chen@intel.com>
+ * Zhao Yakui <yakui.zhao@intel.com>
+ *
+ */
+
+#include <asm/hypervisor.h>
+
+static uint32_t __init acrn_detect(void)
+{
+	return hypervisor_cpuid_base("ACRNACRNACRN\0\0", 0);
+}
+
+static void __init acrn_init_platform(void)
+{
+}
+
+static bool acrn_x2apic_available(void)
+{
+	/* x2apic is not supported now.
+	 * Later it needs to check the X86_FEATURE_X2APIC bit of cpu info
+	 * returned by CPUID to determine whether the x2apic is
+	 * supported in Linux guest.
+	 */
+	return false;
+}
+
+const __initconst struct hypervisor_x86 x86_hyper_acrn = {
+	.name                   = "ACRN",
+	.detect                 = acrn_detect,
+	.type			= X86_HYPER_ACRN,
+	.init.init_platform     = acrn_init_platform,
+	.init.x2apic_available  = acrn_x2apic_available,
+};
diff --git a/arch/x86/kernel/cpu/hypervisor.c b/arch/x86/kernel/cpu/hypervisor.c
index 479ca47..87e39ad 100644
--- a/arch/x86/kernel/cpu/hypervisor.c
+++ b/arch/x86/kernel/cpu/hypervisor.c
@@ -32,6 +32,7 @@ extern const struct hypervisor_x86 x86_hyper_xen_pv;
 extern const struct hypervisor_x86 x86_hyper_xen_hvm;
 extern const struct hypervisor_x86 x86_hyper_kvm;
 extern const struct hypervisor_x86 x86_hyper_jailhouse;
+extern const struct hypervisor_x86 x86_hyper_acrn;
 
 static const __initconst struct hypervisor_x86 * const hypervisors[] =
 {
@@ -49,6 +50,9 @@ static const __initconst struct hypervisor_x86 * const hypervisors[] =
 #ifdef CONFIG_JAILHOUSE_GUEST
 	&x86_hyper_jailhouse,
 #endif
+#ifdef CONFIG_ACRN_GUEST
+	&x86_hyper_acrn,
+#endif
 };
 
 enum x86_hypervisor_type x86_hyper_type;
-- 
2.7.4

[PATCH v7 3/3] x86/acrn: Use HYPERVISOR_CALLBACK_VECTOR for ACRN guest upcall vector

[Zhao Yakui]

Linux kernel uses the HYPERVISOR_CALLBACK_VECTOR for hypervisor upcall
vector. It is already used for Xen and HyperV.
After the ACRN hypervisor is detected, it will also use this defined
vector to notify the ACRN guest.

Co-developed-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
---
V1->V2: Remove the unused API definition of acrn_setup_intr_handler and
acrn_remove_intr_handler.
        Adjust the order of header file
        Add the declaration of acrn_hv_vector_handler and tracing
definition of acrn_hv_callback_vector.

v2->v3: No change
v3->v4: Refine the file name of acrnhyper.h to acrn.h
v5->v6: Add the "extern" for the function declarations in header file
	Add some comments for calling entering_ack_irq
	Some other minor changes(unnecessary spliting two lines.
and minor change in commit log)
v6->v7: Include the header file of asm/apic.h to fix the buidling error
        when enabling cflags="-Werror=implict-function-declaration".
---
 arch/x86/Kconfig            |  1 +
 arch/x86/entry/entry_64.S   |  5 +++++
 arch/x86/include/asm/acrn.h | 11 +++++++++++
 arch/x86/kernel/cpu/acrn.c  | 30 ++++++++++++++++++++++++++++++
 4 files changed, 47 insertions(+)
 create mode 100644 arch/x86/include/asm/acrn.h

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 3020bc7..170d5cf 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -838,6 +838,7 @@ config JAILHOUSE_GUEST
 config ACRN_GUEST
 	bool "ACRN Guest support"
 	depends on X86_64
+	select X86_HV_CALLBACK_VECTOR
 	help
 	  This option allows to run Linux as guest in ACRN hypervisor. Enabling
 	  this will allow the kernel to boot in virtualized environment under
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 11aa3b2..2fe6289 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1142,6 +1142,11 @@ apicinterrupt3 HYPERV_STIMER0_VECTOR \
 	hv_stimer0_callback_vector hv_stimer0_vector_handler
 #endif /* CONFIG_HYPERV */
 
+#if IS_ENABLED(CONFIG_ACRN_GUEST)
+apicinterrupt3 HYPERVISOR_CALLBACK_VECTOR \
+	acrn_hv_callback_vector acrn_hv_vector_handler
+#endif
+
 idtentry debug			do_debug		has_error_code=0	paranoid=1 shift_ist=IST_INDEX_DB ist_offset=DB_STACK_OFFSET
 idtentry int3			do_int3			has_error_code=0	create_gap=1
 idtentry stack_segment		do_stack_segment	has_error_code=1
diff --git a/arch/x86/include/asm/acrn.h b/arch/x86/include/asm/acrn.h
new file mode 100644
index 0000000..4adb13f
--- /dev/null
+++ b/arch/x86/include/asm/acrn.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_ACRN_H
+#define _ASM_X86_ACRN_H
+
+extern void acrn_hv_callback_vector(void);
+#ifdef CONFIG_TRACING
+#define trace_acrn_hv_callback_vector acrn_hv_callback_vector
+#endif
+
+extern void acrn_hv_vector_handler(struct pt_regs *regs);
+#endif /* _ASM_X86_ACRN_H */
diff --git a/arch/x86/kernel/cpu/acrn.c b/arch/x86/kernel/cpu/acrn.c
index f556640..a110c8b 100644
--- a/arch/x86/kernel/cpu/acrn.c
+++ b/arch/x86/kernel/cpu/acrn.c
@@ -9,7 +9,12 @@
  *
  */
 
+#include <linux/interrupt.h>
+#include <asm/acrn.h>
+#include <asm/apic.h>
+#include <asm/desc.h>
 #include <asm/hypervisor.h>
+#include <asm/irq_regs.h>
 
 static uint32_t __init acrn_detect(void)
 {
@@ -18,6 +23,8 @@ static uint32_t __init acrn_detect(void)
 
 static void __init acrn_init_platform(void)
 {
+	/* Setup the IDT for ACRN hypervisor callback */
+	alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, acrn_hv_callback_vector);
 }
 
 static bool acrn_x2apic_available(void)
@@ -30,6 +37,29 @@ static bool acrn_x2apic_available(void)
 	return false;
 }
 
+static void (*acrn_intr_handler)(void);
+
+__visible void __irq_entry acrn_hv_vector_handler(struct pt_regs *regs)
+{
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
+	/*
+	 * The hypervisor requires that the APIC EOI should be acked.
+	 * If the APIC EOI is not acked, the APIC ISR bit for the
+	 * HYPERVISOR_CALLBACK_VECTOR will not be cleared and then it
+	 * will block the interrupt whose vector is lower than
+	 * HYPERVISOR_CALLBACK_VECTOR.
+	 */
+	entering_ack_irq();
+	inc_irq_stat(irq_hv_callback_count);
+
+	if (acrn_intr_handler)
+		acrn_intr_handler();
+
+	exiting_irq();
+	set_irq_regs(old_regs);
+}
+
 const __initconst struct hypervisor_x86 x86_hyper_acrn = {
 	.name                   = "ACRN",
 	.detect                 = acrn_detect,
-- 
2.7.4

[tip:x86/platform] x86/Kconfig: Add new X86_HV_CALLBACK_VECTOR config symbol

[tip-bot for Zhao Yakui]

Commit-ID:  ecca25029473bee6e98ce062e76b7310904bbdd1
Gitweb:     https://git.kernel.org/tip/ecca25029473bee6e98ce062e76b7310904bbdd1
Author:     Zhao Yakui <yakui.zhao@intel.com>
AuthorDate: Tue, 30 Apr 2019 11:45:23 +0800
Committer:  Borislav Petkov <bp@suse.de>
CommitDate: Tue, 11 Jun 2019 21:21:11 +0200

x86/Kconfig: Add new X86_HV_CALLBACK_VECTOR config symbol

Add a special Kconfig symbol X86_HV_CALLBACK_VECTOR so that the guests
using the hypervisor interrupt callback counter can select and thus
enable that counter. Select it when xen or hyperv support is enabled. No
functional changes.

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: linux-hyperv@vger.kernel.org
Cc: Nicolai Stange <nstange@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/1559108037-18813-2-git-send-email-yakui.zhao@intel.com
---
 arch/x86/Kconfig               | 3 +++
 arch/x86/include/asm/hardirq.h | 2 +-
 arch/x86/kernel/irq.c          | 2 +-
 arch/x86/xen/Kconfig           | 1 +
 drivers/hv/Kconfig             | 1 +
 5 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 2bbbd4d1ba31..c9ab09004b16 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -781,6 +781,9 @@ config PARAVIRT_SPINLOCKS
 
 	  If you are unsure how to answer this question, answer Y.
 
+config X86_HV_CALLBACK_VECTOR
+	def_bool n
+
 source "arch/x86/xen/Kconfig"
 
 config KVM_GUEST
diff --git a/arch/x86/include/asm/hardirq.h b/arch/x86/include/asm/hardirq.h
index d9069bb26c7f..07533795b8d2 100644
--- a/arch/x86/include/asm/hardirq.h
+++ b/arch/x86/include/asm/hardirq.h
@@ -37,7 +37,7 @@ typedef struct {
 #ifdef CONFIG_X86_MCE_AMD
 	unsigned int irq_deferred_error_count;
 #endif
-#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
+#ifdef CONFIG_X86_HV_CALLBACK_VECTOR
 	unsigned int irq_hv_callback_count;
 #endif
 #if IS_ENABLED(CONFIG_HYPERV)
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
index 9b68b5b00ac9..4e8f193ad81f 100644
--- a/arch/x86/kernel/irq.c
+++ b/arch/x86/kernel/irq.c
@@ -135,7 +135,7 @@ int arch_show_interrupts(struct seq_file *p, int prec)
 		seq_printf(p, "%10u ", per_cpu(mce_poll_count, j));
 	seq_puts(p, "  Machine check polls\n");
 #endif
-#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
+#ifdef CONFIG_X86_HV_CALLBACK_VECTOR
 	if (test_bit(HYPERVISOR_CALLBACK_VECTOR, system_vectors)) {
 		seq_printf(p, "%*s: ", prec, "HYP");
 		for_each_online_cpu(j)
diff --git a/arch/x86/xen/Kconfig b/arch/x86/xen/Kconfig
index e07abefd3d26..ba5a41828e9d 100644
--- a/arch/x86/xen/Kconfig
+++ b/arch/x86/xen/Kconfig
@@ -7,6 +7,7 @@ config XEN
 	bool "Xen guest support"
 	depends on PARAVIRT
 	select PARAVIRT_CLOCK
+	select X86_HV_CALLBACK_VECTOR
 	depends on X86_64 || (X86_32 && X86_PAE)
 	depends on X86_LOCAL_APIC && X86_TSC
 	help
diff --git a/drivers/hv/Kconfig b/drivers/hv/Kconfig
index 1c1a2514d6f3..cafcb974dcfe 100644
--- a/drivers/hv/Kconfig
+++ b/drivers/hv/Kconfig
@@ -6,6 +6,7 @@ config HYPERV
 	tristate "Microsoft Hyper-V client drivers"
 	depends on X86 && ACPI && X86_LOCAL_APIC && HYPERVISOR_GUEST
 	select PARAVIRT
+	select X86_HV_CALLBACK_VECTOR
 	help
 	  Select this option to run Linux as a Hyper-V client operating
 	  system.

[tip:x86/platform] x86: Add support for Linux guests on an ACRN hypervisor

[tip-bot for Zhao Yakui]

Commit-ID:  ec7972c99fffb4d2739f286ce9b544a71aa1d05f
Gitweb:     https://git.kernel.org/tip/ec7972c99fffb4d2739f286ce9b544a71aa1d05f
Author:     Zhao Yakui <yakui.zhao@intel.com>
AuthorDate: Tue, 30 Apr 2019 11:45:24 +0800
Committer:  Borislav Petkov <bp@suse.de>
CommitDate: Tue, 11 Jun 2019 21:29:22 +0200

x86: Add support for Linux guests on an ACRN hypervisor

ACRN is an open-source hypervisor maintained by The Linux Foundation. It
is built for embedded IOT with small footprint and real-time features.
Add ACRN guest support so that it allows Linux to be booted under the
ACRN hypervisor. This adds only the barebones implementation.

 [ bp: Massage commit message and help text. ]

Co-developed-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/1559108037-18813-3-git-send-email-yakui.zhao@intel.com
---
 arch/x86/Kconfig                  | 10 ++++++++++
 arch/x86/include/asm/hypervisor.h |  1 +
 arch/x86/kernel/cpu/Makefile      |  1 +
 arch/x86/kernel/cpu/acrn.c        | 39 +++++++++++++++++++++++++++++++++++++++
 arch/x86/kernel/cpu/hypervisor.c  |  4 ++++
 5 files changed, 55 insertions(+)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index c9ab09004b16..8a95c50e5c12 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -835,6 +835,16 @@ config JAILHOUSE_GUEST
 	  cell. You can leave this option disabled if you only want to start
 	  Jailhouse and run Linux afterwards in the root cell.
 
+config ACRN_GUEST
+	bool "ACRN Guest support"
+	depends on X86_64
+	help
+	  This option allows to run Linux as guest in the ACRN hypervisor. ACRN is
+	  a flexible, lightweight reference open-source hypervisor, built with
+	  real-time and safety-criticality in mind. It is built for embedded
+	  IOT with small footprint and real-time features. More details can be
+	  found in https://projectacrn.org/.
+
 endif #HYPERVISOR_GUEST
 
 source "arch/x86/Kconfig.cpu"
diff --git a/arch/x86/include/asm/hypervisor.h b/arch/x86/include/asm/hypervisor.h
index 8c5aaba6633f..50a30f6c668b 100644
--- a/arch/x86/include/asm/hypervisor.h
+++ b/arch/x86/include/asm/hypervisor.h
@@ -29,6 +29,7 @@ enum x86_hypervisor_type {
 	X86_HYPER_XEN_HVM,
 	X86_HYPER_KVM,
 	X86_HYPER_JAILHOUSE,
+	X86_HYPER_ACRN,
 };
 
 #ifdef CONFIG_HYPERVISOR_GUEST
diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile
index 5102bf7c8192..3ffe1b0b7516 100644
--- a/arch/x86/kernel/cpu/Makefile
+++ b/arch/x86/kernel/cpu/Makefile
@@ -47,6 +47,7 @@ obj-$(CONFIG_X86_CPU_RESCTRL)		+= resctrl/
 obj-$(CONFIG_X86_LOCAL_APIC)		+= perfctr-watchdog.o
 
 obj-$(CONFIG_HYPERVISOR_GUEST)		+= vmware.o hypervisor.o mshyperv.o
+obj-$(CONFIG_ACRN_GUEST)		+= acrn.o
 
 ifdef CONFIG_X86_FEATURE_NAMES
 quiet_cmd_mkcapflags = MKCAP   $@
diff --git a/arch/x86/kernel/cpu/acrn.c b/arch/x86/kernel/cpu/acrn.c
new file mode 100644
index 000000000000..6d365e97cce6
--- /dev/null
+++ b/arch/x86/kernel/cpu/acrn.c
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ACRN detection support
+ *
+ * Copyright (C) 2019 Intel Corporation. All rights reserved.
+ *
+ * Jason Chen CJ <jason.cj.chen@intel.com>
+ * Zhao Yakui <yakui.zhao@intel.com>
+ *
+ */
+
+#include <asm/hypervisor.h>
+
+static uint32_t __init acrn_detect(void)
+{
+	return hypervisor_cpuid_base("ACRNACRNACRN\0\0", 0);
+}
+
+static void __init acrn_init_platform(void)
+{
+}
+
+static bool acrn_x2apic_available(void)
+{
+	/*
+	 * x2apic is not supported for now. Future enablement will have to check
+	 * X86_FEATURE_X2APIC to determine whether x2apic is supported in the
+	 * guest.
+	 */
+	return false;
+}
+
+const __initconst struct hypervisor_x86 x86_hyper_acrn = {
+	.name                   = "ACRN",
+	.detect                 = acrn_detect,
+	.type			= X86_HYPER_ACRN,
+	.init.init_platform     = acrn_init_platform,
+	.init.x2apic_available  = acrn_x2apic_available,
+};
diff --git a/arch/x86/kernel/cpu/hypervisor.c b/arch/x86/kernel/cpu/hypervisor.c
index 479ca4728de0..87e39ad8d873 100644
--- a/arch/x86/kernel/cpu/hypervisor.c
+++ b/arch/x86/kernel/cpu/hypervisor.c
@@ -32,6 +32,7 @@ extern const struct hypervisor_x86 x86_hyper_xen_pv;
 extern const struct hypervisor_x86 x86_hyper_xen_hvm;
 extern const struct hypervisor_x86 x86_hyper_kvm;
 extern const struct hypervisor_x86 x86_hyper_jailhouse;
+extern const struct hypervisor_x86 x86_hyper_acrn;
 
 static const __initconst struct hypervisor_x86 * const hypervisors[] =
 {
@@ -49,6 +50,9 @@ static const __initconst struct hypervisor_x86 * const hypervisors[] =
 #ifdef CONFIG_JAILHOUSE_GUEST
 	&x86_hyper_jailhouse,
 #endif
+#ifdef CONFIG_ACRN_GUEST
+	&x86_hyper_acrn,
+#endif
 };
 
 enum x86_hypervisor_type x86_hyper_type;

[tip:x86/platform] x86/acrn: Use HYPERVISOR_CALLBACK_VECTOR for ACRN guest upcall vector

[tip-bot for Zhao Yakui]

Commit-ID:  498ad39368865dfdbf15d3516c43694947074b88
Gitweb:     https://git.kernel.org/tip/498ad39368865dfdbf15d3516c43694947074b88
Author:     Zhao Yakui <yakui.zhao@intel.com>
AuthorDate: Tue, 30 Apr 2019 11:45:25 +0800
Committer:  Borislav Petkov <bp@suse.de>
CommitDate: Tue, 11 Jun 2019 21:31:31 +0200

x86/acrn: Use HYPERVISOR_CALLBACK_VECTOR for ACRN guest upcall vector

Use the HYPERVISOR_CALLBACK_VECTOR to notify an ACRN guest.

Co-developed-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/1559108037-18813-4-git-send-email-yakui.zhao@intel.com
---
 arch/x86/Kconfig            |  1 +
 arch/x86/entry/entry_64.S   |  5 +++++
 arch/x86/include/asm/acrn.h | 11 +++++++++++
 arch/x86/kernel/cpu/acrn.c  | 30 ++++++++++++++++++++++++++++++
 4 files changed, 47 insertions(+)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 8a95c50e5c12..0ddcce78f85c 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -838,6 +838,7 @@ config JAILHOUSE_GUEST
 config ACRN_GUEST
 	bool "ACRN Guest support"
 	depends on X86_64
+	select X86_HV_CALLBACK_VECTOR
 	help
 	  This option allows to run Linux as guest in the ACRN hypervisor. ACRN is
 	  a flexible, lightweight reference open-source hypervisor, built with
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 11aa3b2afa4d..2fe62893bbdf 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -1142,6 +1142,11 @@ apicinterrupt3 HYPERV_STIMER0_VECTOR \
 	hv_stimer0_callback_vector hv_stimer0_vector_handler
 #endif /* CONFIG_HYPERV */
 
+#if IS_ENABLED(CONFIG_ACRN_GUEST)
+apicinterrupt3 HYPERVISOR_CALLBACK_VECTOR \
+	acrn_hv_callback_vector acrn_hv_vector_handler
+#endif
+
 idtentry debug			do_debug		has_error_code=0	paranoid=1 shift_ist=IST_INDEX_DB ist_offset=DB_STACK_OFFSET
 idtentry int3			do_int3			has_error_code=0	create_gap=1
 idtentry stack_segment		do_stack_segment	has_error_code=1
diff --git a/arch/x86/include/asm/acrn.h b/arch/x86/include/asm/acrn.h
new file mode 100644
index 000000000000..4adb13f08af7
--- /dev/null
+++ b/arch/x86/include/asm/acrn.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_ACRN_H
+#define _ASM_X86_ACRN_H
+
+extern void acrn_hv_callback_vector(void);
+#ifdef CONFIG_TRACING
+#define trace_acrn_hv_callback_vector acrn_hv_callback_vector
+#endif
+
+extern void acrn_hv_vector_handler(struct pt_regs *regs);
+#endif /* _ASM_X86_ACRN_H */
diff --git a/arch/x86/kernel/cpu/acrn.c b/arch/x86/kernel/cpu/acrn.c
index 6d365e97cce6..676022e71791 100644
--- a/arch/x86/kernel/cpu/acrn.c
+++ b/arch/x86/kernel/cpu/acrn.c
@@ -9,7 +9,12 @@
  *
  */
 
+#include <linux/interrupt.h>
+#include <asm/acrn.h>
+#include <asm/apic.h>
+#include <asm/desc.h>
 #include <asm/hypervisor.h>
+#include <asm/irq_regs.h>
 
 static uint32_t __init acrn_detect(void)
 {
@@ -18,6 +23,8 @@ static uint32_t __init acrn_detect(void)
 
 static void __init acrn_init_platform(void)
 {
+	/* Setup the IDT for ACRN hypervisor callback */
+	alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, acrn_hv_callback_vector);
 }
 
 static bool acrn_x2apic_available(void)
@@ -30,6 +37,29 @@ static bool acrn_x2apic_available(void)
 	return false;
 }
 
+static void (*acrn_intr_handler)(void);
+
+__visible void __irq_entry acrn_hv_vector_handler(struct pt_regs *regs)
+{
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
+	/*
+	 * The hypervisor requires that the APIC EOI should be acked.
+	 * If the APIC EOI is not acked, the APIC ISR bit for the
+	 * HYPERVISOR_CALLBACK_VECTOR will not be cleared and then it
+	 * will block the interrupt whose vector is lower than
+	 * HYPERVISOR_CALLBACK_VECTOR.
+	 */
+	entering_ack_irq();
+	inc_irq_stat(irq_hv_callback_count);
+
+	if (acrn_intr_handler)
+		acrn_intr_handler();
+
+	exiting_irq();
+	set_irq_regs(old_regs);
+}
+
 const __initconst struct hypervisor_x86 x86_hyper_acrn = {
 	.name                   = "ACRN",
 	.detect                 = acrn_detect,