From: Andrew Cooper <andrew.cooper3@citrix.com>
To: Alexander Graf <graf@amazon.com>,
Filippo Sironi <sironi@amazon.de>,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
borntraeger@de.ibm.com, boris.ostrovsky@oracle.com,
cohuck@redhat.com, konrad.wilk@oracle.com,
xen-devel@lists.xenproject.org, vasu.srinivasan@oracle.com
Subject: Re: [PATCH v2 1/2] KVM: Start populating /sys/hypervisor with KVM entries
Date: Thu, 16 May 2019 15:02:00 +0100 [thread overview]
Message-ID: <7aae3e49-5b1c-96d1-466e-5b061305dc9d@citrix.com> (raw)
In-Reply-To: <e976f31b-2ccd-29ba-6a32-2edde49f867f@amazon.com>
On 16/05/2019 14:50, Alexander Graf wrote:
> On 14.05.19 08:16, Filippo Sironi wrote:
>> Start populating /sys/hypervisor with KVM entries when we're running on
>> KVM. This is to replicate functionality that's available when we're
>> running on Xen.
>>
>> Start with /sys/hypervisor/uuid, which users prefer over
>> /sys/devices/virtual/dmi/id/product_uuid as a way to recognize a virtual
>> machine, since it's also available when running on Xen HVM and on Xen PV
>> and, on top of that doesn't require root privileges by default.
>> Let's create arch-specific hooks so that different architectures can
>> provide different implementations.
>>
>> Signed-off-by: Filippo Sironi <sironi@amazon.de>
> I think this needs something akin to
>
> https://www.kernel.org/doc/Documentation/ABI/stable/sysfs-hypervisor-xen
>
> to document which files are available.
>
>> ---
>> v2:
>> * move the retrieval of the VM UUID out of uuid_show and into
>> kvm_para_get_uuid, which is a weak function that can be overwritten
>>
>> drivers/Kconfig | 2 ++
>> drivers/Makefile | 2 ++
>> drivers/kvm/Kconfig | 14 ++++++++++++++
>> drivers/kvm/Makefile | 1 +
>> drivers/kvm/sys-hypervisor.c | 30 ++++++++++++++++++++++++++++++
>> 5 files changed, 49 insertions(+)
>> create mode 100644 drivers/kvm/Kconfig
>> create mode 100644 drivers/kvm/Makefile
>> create mode 100644 drivers/kvm/sys-hypervisor.c
>>
> [...]
>
>> +
>> +__weak const char *kvm_para_get_uuid(void)
>> +{
>> + return NULL;
>> +}
>> +
>> +static ssize_t uuid_show(struct kobject *obj,
>> + struct kobj_attribute *attr,
>> + char *buf)
>> +{
>> + const char *uuid = kvm_para_get_uuid();
>> + return sprintf(buf, "%s\n", uuid);
> The usual return value for the Xen /sys/hypervisor interface is
> "<denied>".
This string comes straight from Xen.
It was an effort to reduce the quantity of interesting fingerprintable
data accessable by default to unprivileged guests.
See
https://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=a2fc8d514df2b38c310d4f4432fe06520b0769ed
~Andrew
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
WARNING: multiple messages have this Message-ID (diff)
From: Andrew Cooper <andrew.cooper3@citrix.com>
To: Alexander Graf <graf@amazon.com>,
Filippo Sironi <sironi@amazon.de>, <linux-kernel@vger.kernel.org>,
<kvm@vger.kernel.org>, <borntraeger@de.ibm.com>,
<boris.ostrovsky@oracle.com>, <cohuck@redhat.com>,
<konrad.wilk@oracle.com>, <xen-devel@lists.xenproject.org>,
<vasu.srinivasan@oracle.com>
Subject: Re: [Xen-devel] [PATCH v2 1/2] KVM: Start populating /sys/hypervisor with KVM entries
Date: Thu, 16 May 2019 15:02:00 +0100 [thread overview]
Message-ID: <7aae3e49-5b1c-96d1-466e-5b061305dc9d@citrix.com> (raw)
Message-ID: <20190516140200.JfFJetuCRlivbTXbKkfU7RJ3bZuFigI9lEap_KmiNCk@z> (raw)
In-Reply-To: <e976f31b-2ccd-29ba-6a32-2edde49f867f@amazon.com>
On 16/05/2019 14:50, Alexander Graf wrote:
> On 14.05.19 08:16, Filippo Sironi wrote:
>> Start populating /sys/hypervisor with KVM entries when we're running on
>> KVM. This is to replicate functionality that's available when we're
>> running on Xen.
>>
>> Start with /sys/hypervisor/uuid, which users prefer over
>> /sys/devices/virtual/dmi/id/product_uuid as a way to recognize a virtual
>> machine, since it's also available when running on Xen HVM and on Xen PV
>> and, on top of that doesn't require root privileges by default.
>> Let's create arch-specific hooks so that different architectures can
>> provide different implementations.
>>
>> Signed-off-by: Filippo Sironi <sironi@amazon.de>
> I think this needs something akin to
>
> https://www.kernel.org/doc/Documentation/ABI/stable/sysfs-hypervisor-xen
>
> to document which files are available.
>
>> ---
>> v2:
>> * move the retrieval of the VM UUID out of uuid_show and into
>> kvm_para_get_uuid, which is a weak function that can be overwritten
>>
>> drivers/Kconfig | 2 ++
>> drivers/Makefile | 2 ++
>> drivers/kvm/Kconfig | 14 ++++++++++++++
>> drivers/kvm/Makefile | 1 +
>> drivers/kvm/sys-hypervisor.c | 30 ++++++++++++++++++++++++++++++
>> 5 files changed, 49 insertions(+)
>> create mode 100644 drivers/kvm/Kconfig
>> create mode 100644 drivers/kvm/Makefile
>> create mode 100644 drivers/kvm/sys-hypervisor.c
>>
> [...]
>
>> +
>> +__weak const char *kvm_para_get_uuid(void)
>> +{
>> + return NULL;
>> +}
>> +
>> +static ssize_t uuid_show(struct kobject *obj,
>> + struct kobj_attribute *attr,
>> + char *buf)
>> +{
>> + const char *uuid = kvm_para_get_uuid();
>> + return sprintf(buf, "%s\n", uuid);
> The usual return value for the Xen /sys/hypervisor interface is
> "<denied>".
This string comes straight from Xen.
It was an effort to reduce the quantity of interesting fingerprintable
data accessable by default to unprivileged guests.
See
https://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=a2fc8d514df2b38c310d4f4432fe06520b0769ed
~Andrew
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
next prev parent reply other threads:[~2019-05-16 14:02 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1539078879-4372-1-git-send-email-sironi@amazon.de>
[not found] ` <c81b65ba-c562-1869-483b-aee5229501e0@de.ibm.com>
2018-10-09 16:21 ` [PATCH] KVM: Start populating /sys/hypervisor with KVM entries Boris Ostrovsky
[not found] ` <61740f41-c7e3-edaf-68ac-2e4c4a99523b@oracle.com>
2018-10-09 17:50 ` Cornelia Huck
2019-05-14 15:16 ` [Xen-devel] " Filippo Sironi
2019-05-14 15:16 ` [Xen-devel] [PATCH v2 1/2] " Filippo Sironi
2019-05-14 15:26 ` Christian Borntraeger
2019-05-14 16:09 ` Sironi, Filippo
2019-05-14 16:09 ` [Xen-devel] " Sironi, Filippo
2019-05-14 16:31 ` Christian Borntraeger
2019-05-14 16:31 ` [Xen-devel] " Christian Borntraeger
2019-05-14 22:08 ` Sironi, Filippo
2019-05-14 22:08 ` [Xen-devel] " Sironi, Filippo
2019-05-14 15:26 ` Christian Borntraeger
2019-05-16 13:50 ` [Xen-devel] " Alexander Graf
2019-05-16 14:02 ` Andrew Cooper [this message]
2019-05-16 14:02 ` Andrew Cooper
2019-05-16 14:08 ` Alexander Graf
2019-05-16 14:08 ` [Xen-devel] " Alexander Graf
2019-05-16 15:02 ` Boris Ostrovsky
2019-05-16 15:14 ` Sironi, Filippo
2019-05-16 15:14 ` [Xen-devel] " Sironi, Filippo
2019-05-16 15:02 ` Boris Ostrovsky
2019-05-17 15:41 ` [Xen-devel] " Sironi, Filippo
2019-05-31 9:06 ` Alexander Graf
2019-05-31 9:12 ` Raslan, KarimAllah
2019-05-31 9:26 ` Alexander Graf
2019-05-31 9:26 ` Alexander Graf
2019-05-31 9:38 ` [Xen-devel] " Marc Zyngier
2019-05-31 9:38 ` Marc Zyngier
2019-05-31 9:12 ` Raslan, KarimAllah
2019-05-31 9:06 ` Alexander Graf
2019-05-17 15:41 ` Sironi, Filippo
2019-05-16 13:50 ` Alexander Graf
2019-05-14 15:16 ` Filippo Sironi
2019-05-14 15:16 ` [Xen-devel] [PATCH v2 2/2] KVM: x86: Implement the arch-specific hook to report the VM UUID Filippo Sironi
2019-05-16 13:56 ` Alexander Graf
2019-05-16 15:25 ` Sironi, Filippo
2019-05-16 15:33 ` Alexander Graf
2019-05-16 16:40 ` Boris Ostrovsky
2019-05-16 17:41 ` Sironi, Filippo
2019-05-16 17:49 ` Alexander Graf
2019-05-16 17:49 ` Alexander Graf
2019-05-16 17:41 ` Sironi, Filippo
2019-05-16 16:40 ` Boris Ostrovsky
2019-05-16 15:33 ` Alexander Graf
2019-05-16 15:25 ` Sironi, Filippo
2019-05-16 13:56 ` Alexander Graf
2019-05-14 15:16 ` Filippo Sironi
2019-05-14 15:16 ` KVM: Start populating /sys/hypervisor with KVM entries Filippo Sironi
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