xen: add xen sysfs nodes

PATCH In review Juergen Gross 2 participants 14 messages Jun 14, 2017 Xen hypervisor interface

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Juergen Gross

author maintainer

2017-06-14 17:23 UTC #0 lore raw

v4 cover xen: add xen sysfs nodes

In order to be able to determine the Xen guest type from within the guest as a user there is currently no stable interface available.

Add a sysfs node for that purpose as the guest type information is available for the kernel.

While doing this document all the other Xen related sysfs nodes.

Add another node to show the Xen hypervisor buildid in order to make hypervisor live patching easier.

Juergen Gross (4):
doc,xen: document hypervisor sysfs nodes for xen
xen: add sysfs node for guest type
xen: sync include/xen/interface/version.h
xen: add sysfs node for hypervisor build id

 Documentation/ABI/stable/sysfs-hypervisor-xen      | 119 +++++++++++++++++++++
 .../{sysfs-hypervisor-pmu => sysfs-hypervisor-xen} |  24 ++++-
 MAINTAINERS                                        |   2 +
 drivers/xen/sys-hypervisor.c                       |  59 ++++++++++
 include/xen/interface/version.h                    |  15 +++
 5 files changed, 217 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/ABI/stable/sysfs-hypervisor-xen
 rename Documentation/ABI/testing/{sysfs-hypervisor-pmu => sysfs-hypervisor-xen} (54%)

Signature · 1 line

2.12.3

Juergen Gross

author maintainer

2017-06-14 17:23 UTC #1 lore raw

PATCH v4 1/4 doc, xen: document hypervisor sysfs nodes for xen

Today only a few sysfs nodes under /sys/hypervisor/ are documented for Xen in Documentation/ABI/testing/sysfs-hypervisor-pmu.

Add the remaining Xen sysfs nodes under /sys/hypervisor/ in a new file Documentation/ABI/stable/sysfs-hypervisor-xen and add the Xen specific sysfs docs to the MAINTAINERS file.

Signed-off-by Juergen Gross <[email protected]>

Reviewed-by Boris Ostrovsky <[email protected]>

---
V4:
- s/full/fully/ (Boris Ostrovsky)
V3:
- added hint for hidden values where appropriate (Andrew Cooper)

V2:
- rename file to Documentation/ABI/stable/sysfs-hypervisor-xen in order to reflect Xen dependency
- leave pmu entries in old file under testing (Boris Ostrovsky)

---
 Documentation/ABI/stable/sysfs-hypervisor-xen | 119 ++++++++++++++++++++++++++
 MAINTAINERS                                   |   2 +
 2 files changed, 121 insertions(+)
 create mode 100644 Documentation/ABI/stable/sysfs-hypervisor-xen

Documentation/ABI/stable/sysfs-hypervisor-xen new file +119 -0

new file mode 100644
index 000000000000..3cf5cdfcd9a8
@@ -0,0 +1,119 @@
+What:		/sys/hypervisor/compilation/compile_date
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Contains the build time stamp of the Xen hypervisor
+		Might return "<denied>" in case of special security settings
+		in the hypervisor.
+
+What:		/sys/hypervisor/compilation/compiled_by
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Contains information who built the Xen hypervisor
+		Might return "<denied>" in case of special security settings
+		in the hypervisor.
+
+What:		/sys/hypervisor/compilation/compiler
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Compiler which was used to build the Xen hypervisor
+		Might return "<denied>" in case of special security settings
+		in the hypervisor.
+
+What:		/sys/hypervisor/properties/capabilities
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Space separated list of supported guest system types. Each type
+		is in the format: <class>-<major>.<minor>-<arch>
+		With:
+			<class>: "xen" -- x86: paravirtualized, arm: standard
+				 "hvm" -- x86 only: fully virtualized
+			<major>: major guest interface version
+			<minor>: minor guest interface version
+			<arch>:  architecture, e.g.:
+				 "x86_32": 32 bit x86 guest without PAE
+				 "x86_32p": 32 bit x86 guest with PAE
+				 "x86_64": 64 bit x86 guest
+				 "armv7l": 32 bit arm guest
+				 "aarch64": 64 bit arm guest
+
+What:		/sys/hypervisor/properties/changeset
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Changeset of the hypervisor (git commit)
+		Might return "<denied>" in case of special security settings
+		in the hypervisor.
+
+What:		/sys/hypervisor/properties/features
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Features the Xen hypervisor supports for the guest as defined
+		in include/xen/interface/features.h printed as a hex value.
+
+What:		/sys/hypervisor/properties/pagesize
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Default page size of the hypervisor printed as a hex value.
+		Might return "0" in case of special security settings
+		in the hypervisor.
+
+What:		/sys/hypervisor/properties/virtual_start
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Virtual address of the hypervisor as a hex value.
+
+What:		/sys/hypervisor/type
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Type of hypervisor:
+		"xen": Xen hypervisor
+
+What:		/sys/hypervisor/uuid
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		UUID of the guest as known to the Xen hypervisor.
+
+What:		/sys/hypervisor/version/extra
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		The Xen version is in the format <major>.<minor><extra>
+		This is the <extra> part of it.
+		Might return "<denied>" in case of special security settings
+		in the hypervisor.
+
+What:		/sys/hypervisor/version/major
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		The Xen version is in the format <major>.<minor><extra>
+		This is the <major> part of it.
+
+What:		/sys/hypervisor/version/minor
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		The Xen version is in the format <major>.<minor><extra>
+		This is the <minor> part of it.

MAINTAINERS +2 -0

index 09b5ab6a8a5c..68c31aebb79c 100644
@@ -13982,6 +13982,8 @@ F:	drivers/xen/
 F:	arch/x86/include/asm/xen/
 F:	include/xen/
 F:	include/uapi/xen/
+F:	Documentation/ABI/stable/sysfs-hypervisor-xen
+F:	Documentation/ABI/testing/sysfs-hypervisor-pmu
 
 XEN HYPERVISOR ARM
 M:	Stefano Stabellini <[email protected]>

Signature · 7 lines

2.12.3


_______________________________________________
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Juergen Gross

author maintainer

2017-06-14 17:24 UTC #2 lore raw

PATCH v4 1/4 doc,xen: document hypervisor sysfs nodes for xen

In reply to Juergen Gross

Today only a few sysfs nodes under /sys/hypervisor/ are documented for Xen in Documentation/ABI/testing/sysfs-hypervisor-pmu.

Add the remaining Xen sysfs nodes under /sys/hypervisor/ in a new file Documentation/ABI/stable/sysfs-hypervisor-xen and add the Xen specific sysfs docs to the MAINTAINERS file.

Signed-off-by Juergen Gross <[email protected]>

Reviewed-by Boris Ostrovsky <[email protected]>

---
V4:
- s/full/fully/ (Boris Ostrovsky)
V3:
- added hint for hidden values where appropriate (Andrew Cooper)

V2:
- rename file to Documentation/ABI/stable/sysfs-hypervisor-xen in order to reflect Xen dependency
- leave pmu entries in old file under testing (Boris Ostrovsky)

---
 Documentation/ABI/stable/sysfs-hypervisor-xen | 119 ++++++++++++++++++++++++++
 MAINTAINERS                                   |   2 +
 2 files changed, 121 insertions(+)
 create mode 100644 Documentation/ABI/stable/sysfs-hypervisor-xen

Documentation/ABI/stable/sysfs-hypervisor-xen new file +119 -0

new file mode 100644
index 000000000000..3cf5cdfcd9a8
@@ -0,0 +1,119 @@
+What:		/sys/hypervisor/compilation/compile_date
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Contains the build time stamp of the Xen hypervisor
+		Might return "<denied>" in case of special security settings
+		in the hypervisor.
+
+What:		/sys/hypervisor/compilation/compiled_by
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Contains information who built the Xen hypervisor
+		Might return "<denied>" in case of special security settings
+		in the hypervisor.
+
+What:		/sys/hypervisor/compilation/compiler
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Compiler which was used to build the Xen hypervisor
+		Might return "<denied>" in case of special security settings
+		in the hypervisor.
+
+What:		/sys/hypervisor/properties/capabilities
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Space separated list of supported guest system types. Each type
+		is in the format: <class>-<major>.<minor>-<arch>
+		With:
+			<class>: "xen" -- x86: paravirtualized, arm: standard
+				 "hvm" -- x86 only: fully virtualized
+			<major>: major guest interface version
+			<minor>: minor guest interface version
+			<arch>:  architecture, e.g.:
+				 "x86_32": 32 bit x86 guest without PAE
+				 "x86_32p": 32 bit x86 guest with PAE
+				 "x86_64": 64 bit x86 guest
+				 "armv7l": 32 bit arm guest
+				 "aarch64": 64 bit arm guest
+
+What:		/sys/hypervisor/properties/changeset
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Changeset of the hypervisor (git commit)
+		Might return "<denied>" in case of special security settings
+		in the hypervisor.
+
+What:		/sys/hypervisor/properties/features
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Features the Xen hypervisor supports for the guest as defined
+		in include/xen/interface/features.h printed as a hex value.
+
+What:		/sys/hypervisor/properties/pagesize
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Default page size of the hypervisor printed as a hex value.
+		Might return "0" in case of special security settings
+		in the hypervisor.
+
+What:		/sys/hypervisor/properties/virtual_start
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Virtual address of the hypervisor as a hex value.
+
+What:		/sys/hypervisor/type
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		Type of hypervisor:
+		"xen": Xen hypervisor
+
+What:		/sys/hypervisor/uuid
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		UUID of the guest as known to the Xen hypervisor.
+
+What:		/sys/hypervisor/version/extra
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		The Xen version is in the format <major>.<minor><extra>
+		This is the <extra> part of it.
+		Might return "<denied>" in case of special security settings
+		in the hypervisor.
+
+What:		/sys/hypervisor/version/major
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		The Xen version is in the format <major>.<minor><extra>
+		This is the <major> part of it.
+
+What:		/sys/hypervisor/version/minor
+Date:		March 2009
+KernelVersion:	2.6.30
+Contact:	[email protected]
+Description:	If running under Xen:
+		The Xen version is in the format <major>.<minor><extra>
+		This is the <minor> part of it.

MAINTAINERS +2 -0

index 09b5ab6a8a5c..68c31aebb79c 100644
@@ -13982,6 +13982,8 @@ F:	drivers/xen/
 F:	arch/x86/include/asm/xen/
 F:	include/xen/
 F:	include/uapi/xen/
+F:	Documentation/ABI/stable/sysfs-hypervisor-xen
+F:	Documentation/ABI/testing/sysfs-hypervisor-pmu
 
 XEN HYPERVISOR ARM
 M:	Stefano Stabellini <[email protected]>

Signature · 1 line

2.12.3

Juergen Gross

author maintainer

2017-06-14 17:23 UTC #3 lore raw

PATCH v4 2/4 xen: add sysfs node for guest type

In reply to Juergen Gross

Currently there is no reliable user interface inside a Xen guest to determine its type (e.g. HVM, PV or PVH). Instead of letting user mode try to determine this by various rather hacky mechanisms (parsing of boot messages before they are gone, trying to make use of known subtle differences in behavior of some instructions), add a sysfs node /sys/hypervisor/guest_type to explicitly deliver this information as it is known to the kernel.

Signed-off-by Juergen Gross <[email protected]>

---
V4:
- use xen_domain_type instead of introducing xen_guest_type (Boris Ostrovsky)
V2:
- remove PVHVM guest type (Andrew Cooper)
- move description to Documentation/ABI/testing/sysfs-hypervisor-xen (Boris Ostrovsky)
- make xen_guest_type const char * (Jan Beulich)
- modify standard ARM guest type to "Xen"

---
 .../{sysfs-hypervisor-pmu => sysfs-hypervisor-xen} | 15 +++++++++--
 MAINTAINERS                                        |  2 +-
 drivers/xen/sys-hypervisor.c                       | 31 ++++++++++++++++++++++
 3 files changed, 45 insertions(+), 3 deletions(-)
 rename Documentation/ABI/testing/{sysfs-hypervisor-pmu => sysfs-hypervisor-xen} (67%)

Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +13 -2

similarity index 67%
rename from Documentation/ABI/testing/sysfs-hypervisor-pmu
rename to Documentation/ABI/testing/sysfs-hypervisor-xen
index 224faa105e18..c0edb3fdd6eb 100644
@@ -1,8 +1,19 @@
+What:		/sys/hypervisor/guest_type
+Date:		May 2017
+KernelVersion:	4.13
+Contact:	[email protected]
+Description:	If running under Xen:
+		Type of guest:
+		"Xen": standard guest type on arm
+		"HVM": fully virtualized guest (x86)
+		"PV": paravirtualized guest (x86)
+		"PVH": fully virtualized guest without legacy emulation (x86)
+
 What:		/sys/hypervisor/pmu/pmu_mode
 Date:		August 2015
 KernelVersion:	4.3
 Contact:	Boris Ostrovsky <[email protected]>
-Description:
+Description:	If running under Xen:
 		Describes mode that Xen's performance-monitoring unit (PMU)
 		uses. Accepted values are
 			"off"  -- PMU is disabled

@@ -17,7 +28,7 @@ What:           /sys/hypervisor/pmu/pmu_features
 Date:           August 2015
 KernelVersion:  4.3
 Contact:        Boris Ostrovsky <[email protected]>
-Description:
+Description:	If running under Xen:
 		Describes Xen PMU features (as an integer). A set bit indicates
 		that the corresponding feature is enabled. See
 		include/xen/interface/xenpmu.h for available features

MAINTAINERS +1 -1

index 68c31aebb79c..5630439429e6 100644
@@ -13983,7 +13983,7 @@ F:	arch/x86/include/asm/xen/
 F:	include/xen/
 F:	include/uapi/xen/
 F:	Documentation/ABI/stable/sysfs-hypervisor-xen
-F:	Documentation/ABI/testing/sysfs-hypervisor-pmu
+F:	Documentation/ABI/testing/sysfs-hypervisor-xen
 
 XEN HYPERVISOR ARM
 M:	Stefano Stabellini <[email protected]>

drivers/xen/sys-hypervisor.c +31 -0

index 84106f9c456c..10400917e8e8 100644
@@ -50,6 +50,32 @@ static int __init xen_sysfs_type_init(void)
 	return sysfs_create_file(hypervisor_kobj, &type_attr.attr);
 }
 
+static ssize_t guest_type_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+	const char *type = "???";
+
+	switch (xen_domain_type) {
+	case XEN_NATIVE:
+		/* ARM only. */
+		type = "Xen";
+		break;
+	case XEN_PV_DOMAIN:
+		type = "PV";
+		break;
+	case XEN_HVM_DOMAIN:
+		type = xen_pvh_domain() ? "PVH" : "HVM";
+		break;
+	}
+	return sprintf(buffer, "%s\n", type);
+}
+
+HYPERVISOR_ATTR_RO(guest_type);
+
+static int __init xen_sysfs_guest_type_init(void)
+{
+	return sysfs_create_file(hypervisor_kobj, &guest_type_attr.attr);
+}
+
 /* xen version attributes */
 static ssize_t major_show(struct hyp_sysfs_attr *attr, char *buffer)
 {

@@ -471,6 +497,9 @@ static int __init hyper_sysfs_init(void)
 	ret = xen_sysfs_type_init();
 	if (ret)
 		goto out;
+	ret = xen_sysfs_guest_type_init();
+	if (ret)
+		goto guest_type_out;
 	ret = xen_sysfs_version_init();
 	if (ret)
 		goto version_out;

@@ -502,6 +531,8 @@ static int __init hyper_sysfs_init(void)
 comp_out:
 	sysfs_remove_group(hypervisor_kobj, &version_group);
 version_out:
+	sysfs_remove_file(hypervisor_kobj, &guest_type_attr.attr);
+guest_type_out:
 	sysfs_remove_file(hypervisor_kobj, &type_attr.attr);
 out:
 	return ret;

Signature · 7 lines

2.12.3


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Boris Ostrovsky

2017-06-14 17:43 UTC #4 lore raw

Re: [PATCH v4 2/4] xen: add sysfs node for guest type

Quoted 26 lines

Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +17 -0

@@ -1,8 +1,19 @@
+What:		/sys/hypervisor/guest_type
+Date:		May 2017
+KernelVersion:	4.13
+Contact:	[email protected]
+Description:	If running under Xen:
+		Type of guest:
+		"Xen": standard guest type on arm
+		"HVM": fully virtualized guest (x86)
+		"PV": paravirtualized guest (x86)
+		"PVH": fully virtualized guest without legacy emulation (x86)
+
 
 
 
 
 
+static ssize_t guest_type_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+	const char *type = "???";
+
+	switch (xen_domain_type) {
+	case XEN_NATIVE:

Documentation/ABI/testing/sysfs-hypervisor-xen

Quoted 10 lines

Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +10 -0
+		/* ARM only. */
+		type = "Xen";
+		break;
+	case XEN_PV_DOMAIN:
+		type = "PV";
+		break;
+	case XEN_HVM_DOMAIN:
+		type = xen_pvh_domain() ? "PVH" : "HVM";
+		break;
+	}

I think we should return -EINVAL for unknown type. Or document "???" in the ABI document.

-boris

Documentation/ABI/testing/sysfs-hypervisor-xen

Quoted 3 lines

Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +2 -0
+	return sprintf(buffer, "%s\n", type);
+}

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Boris Ostrovsky

2017-06-14 17:44 UTC #5 lore raw

Re: [PATCH v4 2/4] xen: add sysfs node for guest type

In reply to Juergen Gross

Quoted 26 lines

Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +17 -0

@@ -1,8 +1,19 @@
+What:		/sys/hypervisor/guest_type
+Date:		May 2017
+KernelVersion:	4.13
+Contact:	[email protected]
+Description:	If running under Xen:
+		Type of guest:
+		"Xen": standard guest type on arm
+		"HVM": fully virtualized guest (x86)
+		"PV": paravirtualized guest (x86)
+		"PVH": fully virtualized guest without legacy emulation (x86)
+
 
 
 
 
 
+static ssize_t guest_type_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+	const char *type = "???";
+
+	switch (xen_domain_type) {
+	case XEN_NATIVE:

Documentation/ABI/testing/sysfs-hypervisor-xen

Quoted 10 lines

Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +10 -0
+		/* ARM only. */
+		type = "Xen";
+		break;
+	case XEN_PV_DOMAIN:
+		type = "PV";
+		break;
+	case XEN_HVM_DOMAIN:
+		type = xen_pvh_domain() ? "PVH" : "HVM";
+		break;
+	}

I think we should return -EINVAL for unknown type. Or document "???" in the ABI document.

-boris

Quoted 3 lines

Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +2 -0
+	return sprintf(buffer, "%s\n", type);
+}

Juergen Gross

author maintainer

2017-06-14 18:52 UTC #6 lore raw

Re: [PATCH v4 2/4] xen: add sysfs node for guest type

Quoted 31 lines · Boris Ostrovsky

Quoted 31 lines

Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +22 -0

@@ -1,8 +1,19 @@
+What:		/sys/hypervisor/guest_type
+Date:		May 2017
+KernelVersion:	4.13
+Contact:	[email protected]
+Description:	If running under Xen:
+		Type of guest:
+		"Xen": standard guest type on arm
+		"HVM": fully virtualized guest (x86)
+		"PV": paravirtualized guest (x86)
+		"PVH": fully virtualized guest without legacy emulation (x86)
+
 
 
 
 
 
+static ssize_t guest_type_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+	const char *type = "???";
+
+	switch (xen_domain_type) {
+	case XEN_NATIVE:
+		/* ARM only. */
+		type = "Xen";
+		break;
+	case XEN_PV_DOMAIN:
+		type = "PV";

Quoted 8 lines

Documentation/ABI/testing/sysfs-hypervisor-xen
Quoted 5 lines
Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +5 -0
+		break;
+	case XEN_HVM_DOMAIN:
+		type = xen_pvh_domain() ? "PVH" : "HVM";
+		break;
+	}
I think we should return -EINVAL for unknown type. Or document "???" in the ABI document.

Hmm, okay. Are you fine with the attached patch?

Juergen

Quoted 1 line

From b8661036e7465eab99f988cec3fe37e35536eb40 Mon Sep 17 00:00:00 2001

From: Juergen Gross <[email protected]>
Date: Wed, 14 Jun 2017 17:12:45 +0200
Subject: [PATCH v5] xen: add sysfs node for guest type

Signed-off-by Juergen Gross <[email protected]>

---
 .../{sysfs-hypervisor-pmu => sysfs-hypervisor-xen} | 15 ++++++++--
 MAINTAINERS                                        |  2 +-
 drivers/xen/sys-hypervisor.c                       | 34 ++++++++++++++++++++++
 3 files changed, 48 insertions(+), 3 deletions(-)
 rename Documentation/ABI/testing/{sysfs-hypervisor-pmu => sysfs-hypervisor-xen} (67%)

Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +13 -2

similarity index 67%
rename from Documentation/ABI/testing/sysfs-hypervisor-pmu
rename to Documentation/ABI/testing/sysfs-hypervisor-xen
index 224faa105e18..c0edb3fdd6eb 100644
@@ -1,8 +1,19 @@
+What:		/sys/hypervisor/guest_type
+Date:		May 2017
+KernelVersion:	4.13
+Contact:	[email protected]
+Description:	If running under Xen:
+		Type of guest:
+		"Xen": standard guest type on arm
+		"HVM": fully virtualized guest (x86)
+		"PV": paravirtualized guest (x86)
+		"PVH": fully virtualized guest without legacy emulation (x86)
+
 What:		/sys/hypervisor/pmu/pmu_mode
 Date:		August 2015
 KernelVersion:	4.3
 Contact:	Boris Ostrovsky <[email protected]>
-Description:
+Description:	If running under Xen:
 		Describes mode that Xen's performance-monitoring unit (PMU)
 		uses. Accepted values are
 			"off"  -- PMU is disabled

@@ -17,7 +28,7 @@ What:           /sys/hypervisor/pmu/pmu_features
 Date:           August 2015
 KernelVersion:  4.3
 Contact:        Boris Ostrovsky <[email protected]>
-Description:
+Description:	If running under Xen:
 		Describes Xen PMU features (as an integer). A set bit indicates
 		that the corresponding feature is enabled. See
 		include/xen/interface/xenpmu.h for available features

MAINTAINERS +1 -1

index 68c31aebb79c..5630439429e6 100644
@@ -13983,7 +13983,7 @@ F:	arch/x86/include/asm/xen/
 F:	include/xen/
 F:	include/uapi/xen/
 F:	Documentation/ABI/stable/sysfs-hypervisor-xen
-F:	Documentation/ABI/testing/sysfs-hypervisor-pmu
+F:	Documentation/ABI/testing/sysfs-hypervisor-xen
 
 XEN HYPERVISOR ARM
 M:	Stefano Stabellini <[email protected]>

drivers/xen/sys-hypervisor.c +34 -0

index 84106f9c456c..2f78f84a31e9 100644
@@ -50,6 +50,35 @@ static int __init xen_sysfs_type_init(void)
 	return sysfs_create_file(hypervisor_kobj, &type_attr.attr);
 }
 
+static ssize_t guest_type_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+	const char *type;
+
+	switch (xen_domain_type) {
+	case XEN_NATIVE:
+		/* ARM only. */
+		type = "Xen";
+		break;
+	case XEN_PV_DOMAIN:
+		type = "PV";
+		break;
+	case XEN_HVM_DOMAIN:
+		type = xen_pvh_domain() ? "PVH" : "HVM";
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sprintf(buffer, "%s\n", type);
+}
+
+HYPERVISOR_ATTR_RO(guest_type);
+
+static int __init xen_sysfs_guest_type_init(void)
+{
+	return sysfs_create_file(hypervisor_kobj, &guest_type_attr.attr);
+}
+
 /* xen version attributes */
 static ssize_t major_show(struct hyp_sysfs_attr *attr, char *buffer)
 {

@@ -471,6 +500,9 @@ static int __init hyper_sysfs_init(void)
 	ret = xen_sysfs_type_init();
 	if (ret)
 		goto out;
+	ret = xen_sysfs_guest_type_init();
+	if (ret)
+		goto guest_type_out;
 	ret = xen_sysfs_version_init();
 	if (ret)
 		goto version_out;

@@ -502,6 +534,8 @@ static int __init hyper_sysfs_init(void)
 comp_out:
 	sysfs_remove_group(hypervisor_kobj, &version_group);
 version_out:
+	sysfs_remove_file(hypervisor_kobj, &guest_type_attr.attr);
+guest_type_out:
 	sysfs_remove_file(hypervisor_kobj, &type_attr.attr);
 out:
 	return ret;

Signature · 1 line

2.12.3

Boris Ostrovsky

Reviewed-by

2017-06-14 18:56 UTC #7 lore raw

Re: [PATCH v4 2/4] xen: add sysfs node for guest type

Quoted 2 lines

Hmm, okay. Are you fine with the attached patch?

Reviewed-by Boris Ostrovsky <[email protected]>

_______________________________________________
Xen-devel mailing list
[email protected]
https://lists.xen.org/xen-devel

Juergen Gross

author maintainer

2017-06-14 18:52 UTC #8 lore raw

Re: [PATCH v4 2/4] xen: add sysfs node for guest type

In reply to Boris Ostrovsky

Quoted 31 lines · Boris Ostrovsky

Quoted 31 lines

Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +22 -0

@@ -1,8 +1,19 @@
+What:		/sys/hypervisor/guest_type
+Date:		May 2017
+KernelVersion:	4.13
+Contact:	[email protected]
+Description:	If running under Xen:
+		Type of guest:
+		"Xen": standard guest type on arm
+		"HVM": fully virtualized guest (x86)
+		"PV": paravirtualized guest (x86)
+		"PVH": fully virtualized guest without legacy emulation (x86)
+
 
 
 
 
 
+static ssize_t guest_type_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+	const char *type = "???";
+
+	switch (xen_domain_type) {
+	case XEN_NATIVE:
+		/* ARM only. */
+		type = "Xen";
+		break;
+	case XEN_PV_DOMAIN:
+		type = "PV";

Quoted 8 lines

Documentation/ABI/testing/sysfs-hypervisor-xen
Quoted 5 lines
Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +5 -0
+		break;
+	case XEN_HVM_DOMAIN:
+		type = xen_pvh_domain() ? "PVH" : "HVM";
+		break;
+	}
I think we should return -EINVAL for unknown type. Or document "???" in the ABI document.

Hmm, okay. Are you fine with the attached patch?

Juergen

Quoted 1 line

From b8661036e7465eab99f988cec3fe37e35536eb40 Mon Sep 17 00:00:00 2001

From: Juergen Gross <[email protected]>
Date: Wed, 14 Jun 2017 17:12:45 +0200
Subject: [PATCH v5] xen: add sysfs node for guest type

Signed-off-by Juergen Gross <[email protected]>

---
 .../{sysfs-hypervisor-pmu => sysfs-hypervisor-xen} | 15 ++++++++--
 MAINTAINERS                                        |  2 +-
 drivers/xen/sys-hypervisor.c                       | 34 ++++++++++++++++++++++
 3 files changed, 48 insertions(+), 3 deletions(-)
 rename Documentation/ABI/testing/{sysfs-hypervisor-pmu => sysfs-hypervisor-xen} (67%)

Documentation/ABI/testing/sysfs-hypervisor-xen renamed from Documentation/ABI/testing/sysfs-hypervisor-pmu +13 -2

similarity index 67%
rename from Documentation/ABI/testing/sysfs-hypervisor-pmu
rename to Documentation/ABI/testing/sysfs-hypervisor-xen
index 224faa105e18..c0edb3fdd6eb 100644
@@ -1,8 +1,19 @@
+What:		/sys/hypervisor/guest_type
+Date:		May 2017
+KernelVersion:	4.13
+Contact:	[email protected]
+Description:	If running under Xen:
+		Type of guest:
+		"Xen": standard guest type on arm
+		"HVM": fully virtualized guest (x86)
+		"PV": paravirtualized guest (x86)
+		"PVH": fully virtualized guest without legacy emulation (x86)
+
 What:		/sys/hypervisor/pmu/pmu_mode
 Date:		August 2015
 KernelVersion:	4.3
 Contact:	Boris Ostrovsky <[email protected]>
-Description:
+Description:	If running under Xen:
 		Describes mode that Xen's performance-monitoring unit (PMU)
 		uses. Accepted values are
 			"off"  -- PMU is disabled

@@ -17,7 +28,7 @@ What:           /sys/hypervisor/pmu/pmu_features
 Date:           August 2015
 KernelVersion:  4.3
 Contact:        Boris Ostrovsky <[email protected]>
-Description:
+Description:	If running under Xen:
 		Describes Xen PMU features (as an integer). A set bit indicates
 		that the corresponding feature is enabled. See
 		include/xen/interface/xenpmu.h for available features

MAINTAINERS +1 -1

index 68c31aebb79c..5630439429e6 100644
@@ -13983,7 +13983,7 @@ F:	arch/x86/include/asm/xen/
 F:	include/xen/
 F:	include/uapi/xen/
 F:	Documentation/ABI/stable/sysfs-hypervisor-xen
-F:	Documentation/ABI/testing/sysfs-hypervisor-pmu
+F:	Documentation/ABI/testing/sysfs-hypervisor-xen
 
 XEN HYPERVISOR ARM
 M:	Stefano Stabellini <[email protected]>

drivers/xen/sys-hypervisor.c +34 -0

index 84106f9c456c..2f78f84a31e9 100644
@@ -50,6 +50,35 @@ static int __init xen_sysfs_type_init(void)
 	return sysfs_create_file(hypervisor_kobj, &type_attr.attr);
 }
 
+static ssize_t guest_type_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+	const char *type;
+
+	switch (xen_domain_type) {
+	case XEN_NATIVE:
+		/* ARM only. */
+		type = "Xen";
+		break;
+	case XEN_PV_DOMAIN:
+		type = "PV";
+		break;
+	case XEN_HVM_DOMAIN:
+		type = xen_pvh_domain() ? "PVH" : "HVM";
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return sprintf(buffer, "%s\n", type);
+}
+
+HYPERVISOR_ATTR_RO(guest_type);
+
+static int __init xen_sysfs_guest_type_init(void)
+{
+	return sysfs_create_file(hypervisor_kobj, &guest_type_attr.attr);
+}
+
 /* xen version attributes */
 static ssize_t major_show(struct hyp_sysfs_attr *attr, char *buffer)
 {

@@ -471,6 +500,9 @@ static int __init hyper_sysfs_init(void)
 	ret = xen_sysfs_type_init();
 	if (ret)
 		goto out;
+	ret = xen_sysfs_guest_type_init();
+	if (ret)
+		goto guest_type_out;
 	ret = xen_sysfs_version_init();
 	if (ret)
 		goto version_out;

@@ -502,6 +534,8 @@ static int __init hyper_sysfs_init(void)
 comp_out:
 	sysfs_remove_group(hypervisor_kobj, &version_group);
 version_out:
+	sysfs_remove_file(hypervisor_kobj, &guest_type_attr.attr);
+guest_type_out:
 	sysfs_remove_file(hypervisor_kobj, &type_attr.attr);
 out:
 	return ret;

Signature · 1 line

2.12.3

_______________________________________________
Xen-devel mailing list
[email protected]
https://lists.xen.org/xen-devel

Juergen Gross

author maintainer

2017-06-14 17:23 UTC #9 lore raw

PATCH v4 3/4 xen: sync include/xen/interface/version.h

In reply to Juergen Gross

Sync include/xen/interface/version.h with the Xen source.

Signed-off-by Juergen Gross <[email protected]>

Reviewed-by Boris Ostrovsky <[email protected]>

---
 include/xen/interface/version.h | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

include/xen/interface/version.h +15 -0

index 7ff6498679a3..145f12f9ecec 100644
@@ -63,4 +63,19 @@ struct xen_feature_info {
 /* arg == xen_domain_handle_t. */
 #define XENVER_guest_handle 8
 
+#define XENVER_commandline 9
+struct xen_commandline {
+	char buf[1024];
+};
+
+/*
+ * Return value is the number of bytes written, or XEN_Exx on error.
+ * Calling with empty parameter returns the size of build_id.
+ */
+#define XENVER_build_id 10
+struct xen_build_id {
+	uint32_t	len; /* IN: size of buf[]. */
+	unsigned char	buf[];
+};
+
 #endif /* __XEN_PUBLIC_VERSION_H__ */

Signature · 7 lines

2.12.3


_______________________________________________
Xen-devel mailing list
[email protected]
https://lists.xen.org/xen-devel

Juergen Gross

author maintainer

2017-06-14 17:24 UTC #10 lore raw

PATCH v4 3/4 xen: sync include/xen/interface/version.h

In reply to Juergen Gross

Sync include/xen/interface/version.h with the Xen source.

Signed-off-by Juergen Gross <[email protected]>

Reviewed-by Boris Ostrovsky <[email protected]>

---
 include/xen/interface/version.h | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

include/xen/interface/version.h +15 -0

index 7ff6498679a3..145f12f9ecec 100644
@@ -63,4 +63,19 @@ struct xen_feature_info {
 /* arg == xen_domain_handle_t. */
 #define XENVER_guest_handle 8
 
+#define XENVER_commandline 9
+struct xen_commandline {
+	char buf[1024];
+};
+
+/*
+ * Return value is the number of bytes written, or XEN_Exx on error.
+ * Calling with empty parameter returns the size of build_id.
+ */
+#define XENVER_build_id 10
+struct xen_build_id {
+	uint32_t	len; /* IN: size of buf[]. */
+	unsigned char	buf[];
+};
+
 #endif /* __XEN_PUBLIC_VERSION_H__ */

Signature · 1 line

2.12.3

Juergen Gross

author maintainer

2017-06-14 17:23 UTC #11 lore raw

PATCH v4 4/4 xen: add sysfs node for hypervisor build id

In reply to Juergen Gross

For support of Xen hypervisor live patching the hypervisor build id is needed. Add a node /sys/hypervisor/properties/buildid containing the information.

Signed-off-by Juergen Gross <[email protected]>

---
V4:
- send correct patch

---
 Documentation/ABI/testing/sysfs-hypervisor-xen | 11 +++++++++-
 drivers/xen/sys-hypervisor.c                   | 28 ++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 1 deletion(-)

Documentation/ABI/testing/sysfs-hypervisor-xen +10 -1

index c0edb3fdd6eb..53b7b2ea7515 100644
@@ -1,5 +1,5 @@
 What:		/sys/hypervisor/guest_type
-Date:		May 2017
+Date:		June 2017
 KernelVersion:	4.13
 Contact:	[email protected]
 Description:	If running under Xen:

@@ -32,3 +32,12 @@ Description:	If running under Xen:
 		Describes Xen PMU features (as an integer). A set bit indicates
 		that the corresponding feature is enabled. See
 		include/xen/interface/xenpmu.h for available features
+
+What:		/sys/hypervisor/properties/buildid
+Date:		June 2017
+KernelVersion:	4.13
+Contact:	[email protected]
+Description:	If running under Xen:
+		Build id of the hypervisor, needed for hypervisor live patching.
+		Might return "<denied>" in case of special security settings
+		in the hypervisor.

drivers/xen/sys-hypervisor.c +28 -0

index 10400917e8e8..f8eeed46fbc3 100644
@@ -353,12 +353,40 @@ static ssize_t features_show(struct hyp_sysfs_attr *attr, char *buffer)
 
 HYPERVISOR_ATTR_RO(features);
 
+static ssize_t buildid_show(struct hyp_sysfs_attr *attr, char *buffer)
+{
+	ssize_t ret;
+	struct xen_build_id *buildid;
+
+	ret = HYPERVISOR_xen_version(XENVER_build_id, NULL);
+	if (ret < 0) {
+		if (ret == -EPERM)
+			ret = sprintf(buffer, "<denied>");
+		return ret;
+	}
+
+	buildid = kmalloc(sizeof(*buildid) + ret, GFP_KERNEL);
+	if (!buildid)
+		return -ENOMEM;
+
+	buildid->len = ret;
+	ret = HYPERVISOR_xen_version(XENVER_build_id, buildid);
+	if (ret > 0)
+		ret = sprintf(buffer, "%s", buildid->buf);
+	kfree(buildid);
+
+	return ret;
+}
+
+HYPERVISOR_ATTR_RO(buildid);
+
 static struct attribute *xen_properties_attrs[] = {
 	&capabilities_attr.attr,
 	&changeset_attr.attr,
 	&virtual_start_attr.attr,
 	&pagesize_attr.attr,
 	&features_attr.attr,
+	&buildid_attr.attr,
 	NULL
 };

Signature · 7 lines

2.12.3


_______________________________________________
Xen-devel mailing list
[email protected]
https://lists.xen.org/xen-devel

Boris Ostrovsky

Reviewed-by on v4 4/4

2017-06-14 17:45 UTC #12 lore raw

Re: [PATCH v4 4/4] xen: add sysfs node for hypervisor build id

Quoted 5 lines · Juergen Gross

For support of Xen hypervisor live patching the hypervisor build id is needed. Add a node /sys/hypervisor/properties/buildid containing the information.
Signed-off-by Juergen Gross <[email protected]>

Reviewed-by Boris Ostrovsky <[email protected]>

_______________________________________________
Xen-devel mailing list
[email protected]
https://lists.xen.org/xen-devel

Boris Ostrovsky

Reviewed-by on v4 4/4

2017-06-14 17:45 UTC #13 lore raw

Re: [PATCH v4 4/4] xen: add sysfs node for hypervisor build id

In reply to Juergen Gross

Quoted 5 lines · Juergen Gross

For support of Xen hypervisor live patching the hypervisor build id is needed. Add a node /sys/hypervisor/properties/buildid containing the information.
Signed-off-by Juergen Gross <[email protected]>

Reviewed-by Boris Ostrovsky <[email protected]>