add documentation for pci passthrough and sr-iov

[pve-docs.git] / qm.adoc

diff --git a/qm.adoc b/qm.adoc
index 974becf90e6efcdfa8f5b017c90c6af7d09469b4..0d453c8bc5c94356b84f768b06e6c32802b3d74e 100644 (file)
--- a/qm.adoc
+++ b/qm.adoc
@@ -199,6 +199,11 @@ when the filesystem of a VM marks blocks as unused after removing files, the
 emulated SCSI controller will relay this information to the storage, which will
 then shrink the disk image accordingly.
 
 emulated SCSI controller will relay this information to the storage, which will
 then shrink the disk image accordingly.
 

+If you would like a drive to be presented to the guest as a solid-state drive
+rather than a rotational hard disk, you can set the *SSD emulation* option on
+that drive. There is no requirement that the underlying storage actually be
+backed by SSDs; this feature can be used with physical media of any type.
+

 .IO Thread
 The option *IO Thread* can only be used when using a disk with the
 *VirtIO* controller, or with the *SCSI* controller, when the emulated controller
 .IO Thread
 The option *IO Thread* can only be used when using a disk with the
 *VirtIO* controller, or with the *SCSI* controller, when the emulated controller


@@ -335,7 +340,7 @@ To check if the {pve} host is vulnerable, execute the following command as root:
 for f in /sys/devices/system/cpu/vulnerabilities/*; do echo "${f##*/} -" $(cat "$f"); done
 ----
 
 for f in /sys/devices/system/cpu/vulnerabilities/*; do echo "${f##*/} -" $(cat "$f"); done
 ----
 

-A community script is also avalaible to detect is the host is still vulnerable.
+A community script is also available to detect is the host is still vulnerable.

 footnote:[spectre-meltdown-checker https://meltdown.ovh/]
 
 Intel processors
 footnote:[spectre-meltdown-checker https://meltdown.ovh/]
 
 Intel processors


@@ -343,7 +348,7 @@ Intel processors
 
 * 'pcid'
 +
 
 * 'pcid'
 +

-This reduce the performance impact of the Meltdown (CVE-2017-5754) mitigation 
+This reduces the performance impact of the Meltdown (CVE-2017-5754) mitigation

 called 'Kernel Page-Table Isolation (KPTI)', which effectively hides
 the Kernel memory from the user space. Without PCID, KPTI is quite an expensive
 mechanism footnote:[PCID is now a critical performance/security feature on x86
 called 'Kernel Page-Table Isolation (KPTI)', which effectively hides
 the Kernel memory from the user space. Without PCID, KPTI is quite an expensive
 mechanism footnote:[PCID is now a critical performance/security feature on x86


@@ -359,17 +364,17 @@ If this does not return empty your host's CPU has support for 'pcid'.
 
 * 'spec-ctrl'
 +
 
 * 'spec-ctrl'
 +

-Required to enable the Spectre v1 (CVE-2017-5753) and Spectre v2 (CVE-2017-5715) fix, 
-in cases where retpolines are not sufficient. 
-Included by default in Intel CPU models with -IBRS suffix. 
-Must be explicitly turned on for Intel CPU models without -IBRS suffix. 
-Requires the host CPU microcode (intel-microcode >= 20180425).
+Required to enable the Spectre v1 (CVE-2017-5753) and Spectre v2 (CVE-2017-5715) fix,
+in cases where retpolines are not sufficient.
+Included by default in Intel CPU models with -IBRS suffix.
+Must be explicitly turned on for Intel CPU models without -IBRS suffix.
+Requires an updated host CPU microcode (intel-microcode >= 20180425).

 +
 * 'ssbd'
 +
 +
 * 'ssbd'
 +

-Required to enable the Spectre V4 (CVE-2018-3639) fix. Not included by default in any Intel CPU model. 
-Must be explicitly turned on for all Intel CPU models. 
-Requires the host CPU microcode(intel-microcode >= 20180703).
+Required to enable the Spectre V4 (CVE-2018-3639) fix. Not included by default in any Intel CPU model.
+Must be explicitly turned on for all Intel CPU models.
+Requires an updated host CPU microcode(intel-microcode >= 20180703).

 
 
 AMD processors
 
 
 AMD processors


@@ -377,10 +382,10 @@ AMD processors
 
 * 'ibpb'
 +
 
 * 'ibpb'
 +

-Required to enable the Spectre v1 (CVE-2017-5753) and Spectre v2 (CVE-2017-5715) fix, 
-in cases where retpolines are not sufficient. 
-Included by default in AMD CPU models with -IBPB suffix. 
-Must be explicitly turned on for AMD CPU models without -IBPB suffix. 
+Required to enable the Spectre v1 (CVE-2017-5753) and Spectre v2 (CVE-2017-5715) fix,
+in cases where retpolines are not sufficient.
+Included by default in AMD CPU models with -IBPB suffix.
+Must be explicitly turned on for AMD CPU models without -IBPB suffix.

 Requires the host CPU microcode to support this feature before it can be used for guest CPUs.
 
 
 Requires the host CPU microcode to support this feature before it can be used for guest CPUs.
 
 


@@ -388,27 +393,27 @@ Requires the host CPU microcode to support this feature before it can be used fo
 * 'virt-ssbd'
 +
 Required to enable the Spectre v4 (CVE-2018-3639) fix.
 * 'virt-ssbd'
 +
 Required to enable the Spectre v4 (CVE-2018-3639) fix.

-Not included by default in any AMD CPU model. 
-Must be explicitly turned on for all AMD CPU models. 
-This should be provided to guests, even if amd-ssbd is also provided, for maximum guest compatibility. 
-Note for some QEMU / libvirt versions, this must be force enabled when when using "Host model", 
-because this is a virtual feature that doesn’t exist in the physical host CPUs.
+Not included by default in any AMD CPU model.
+Must be explicitly turned on for all AMD CPU models.
+This should be provided to guests, even if amd-ssbd is also provided, for maximum guest compatibility.
+Note that this must be explicitly enabled when when using the "host" cpu model,
+because this is a virtual feature which does not exist in the physical CPUs.

 
 
 * 'amd-ssbd'
 +
 
 
 * 'amd-ssbd'
 +

-Required to enable the Spectre v4 (CVE-2018-3639) fix. 
-Not included by default in any AMD CPU model. Must be explicitly turned on for all AMD CPU models. 
-This provides higher performance than virt-ssbd so should be exposed to guests whenever available in the host. 
+Required to enable the Spectre v4 (CVE-2018-3639) fix.
+Not included by default in any AMD CPU model. Must be explicitly turned on for all AMD CPU models.
+This provides higher performance than virt-ssbd, therefore a host supporting this should always expose this to guests if possible.

 virt-ssbd should none the less also be exposed for maximum guest compatibility as some kernels only know about virt-ssbd.
 
 
 * 'amd-no-ssb'
 +
 Recommended to indicate the host is not vulnerable to Spectre V4 (CVE-2018-3639).
 virt-ssbd should none the less also be exposed for maximum guest compatibility as some kernels only know about virt-ssbd.
 
 
 * 'amd-no-ssb'
 +
 Recommended to indicate the host is not vulnerable to Spectre V4 (CVE-2018-3639).

-Not included by default in any AMD CPU model. 
-Future hardware generations of CPU will not be vulnerable to CVE-2018-3639, 
-and thus the guest should be told not to enable its mitigations, by exposing amd-no-ssb. 
+Not included by default in any AMD CPU model.
+Future hardware generations of CPU will not be vulnerable to CVE-2018-3639,
+and thus the guest should be told not to enable its mitigations, by exposing amd-no-ssb.

 This is mutually exclusive with virt-ssbd and amd-ssbd.
 
 
 This is mutually exclusive with virt-ssbd and amd-ssbd.
 
 


@@ -590,6 +595,39 @@ traffic increases. We recommend to set this option only when the VM has to
 process a great number of incoming connections, such as when the VM is running
 as a router, reverse proxy or a busy HTTP server doing long polling.
 
 process a great number of incoming connections, such as when the VM is running
 as a router, reverse proxy or a busy HTTP server doing long polling.
 

+[[qm_display]]
+Display
+~~~~~~~
+
+QEMU can virtualize a few types of VGA hardware. Some examples are:
+
+* *std*, the default, emulates a card with Bochs VBE extensions.
+* *cirrus*, this was once the default, it emulates a very old hardware module
+with all its problems. This display type should only be used if really
+necessary footnote:[https://www.kraxel.org/blog/2014/10/qemu-using-cirrus-considered-harmful/
+qemu: using cirrus considered harmful], e.g., if using Windows XP or earlier
+* *vmware*, is a VMWare SVGA-II compatible adapter.
+* *qxl*, is the QXL paravirtualized graphics card. Selecting this also
+enables SPICE for the VM.
+
+You can edit the amount of memory given to the virtual GPU, by setting
+the 'memory' option. This can enable higher resolutions inside the VM,
+especially with SPICE/QXL.
+
+As the memory is reserved by display device, selecting Multi-Monitor mode
+for SPICE (e.g., `qxl2` for dual monitors) has some implications:
+
+* Windows needs a device for each monitor, so if your 'ostype' is some
+version of Windows, {pve} gives the VM an extra device per monitor.
+Each device gets the specified amount of memory.
+
+* Linux VMs, can always enable more virtual monitors, but selecting
+a Multi-Monitor mode multiplies the memory given to the device with
+the number of monitors.
+
+Selecting `serialX` as display 'type' disables the VGA output, and redirects
+the Web Console to the selected serial port. A configured display 'memory'
+setting will be ignored in that case.

 
 [[qm_usb_passthrough]]
 USB Passthrough
 
 [[qm_usb_passthrough]]
 USB Passthrough


@@ -845,7 +883,7 @@ clone and modify that.
 VM Generation ID
 ----------------
 
 VM Generation ID
 ----------------
 

-{pve} supports Virtual Machine Generation ID ('vmgedid') footnote:[Official
+{pve} supports Virtual Machine Generation ID ('vmgenid') footnote:[Official

 'vmgenid' Specification
 https://docs.microsoft.com/en-us/windows/desktop/hyperv_v2/virtual-machine-generation-identifier]
 for virtual machines.
 'vmgenid' Specification
 https://docs.microsoft.com/en-us/windows/desktop/hyperv_v2/virtual-machine-generation-identifier]
 for virtual machines.


@@ -919,13 +957,13 @@ Step-by-step example of a Windows OVF import
 
 Microsoft provides
 https://developer.microsoft.com/en-us/windows/downloads/virtual-machines/[Virtual Machines downloads]
 
 Microsoft provides
 https://developer.microsoft.com/en-us/windows/downloads/virtual-machines/[Virtual Machines downloads]

- to get started with Windows development.We are going to use one of these 
+ to get started with Windows development.We are going to use one of these

 to demonstrate the OVF import feature.
 
 Download the Virtual Machine zip
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 to demonstrate the OVF import feature.
 
 Download the Virtual Machine zip
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 

-After getting informed about the user agreement, choose the _Windows 10 
+After getting informed about the user agreement, choose the _Windows 10

 Enterprise (Evaluation - Build)_ for the VMware platform, and download the zip.
 
 Extract the disk image from the zip
 Enterprise (Evaluation - Build)_ for the VMware platform, and download the zip.
 
 Extract the disk image from the zip


@@ -948,7 +986,7 @@ The VM is ready to be started.
 Adding an external disk image to a Virtual Machine
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 Adding an external disk image to a Virtual Machine
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

-You can also add an existing disk image to a VM, either coming from a 
+You can also add an existing disk image to a VM, either coming from a

 foreign hypervisor, or one that you created yourself.
 
 Suppose you created a Debian/Ubuntu disk image with the 'vmdebootstrap' tool:
 foreign hypervisor, or one that you created yourself.
 
 Suppose you created a Debian/Ubuntu disk image with the 'vmdebootstrap' tool:


@@ -983,6 +1021,9 @@ ifndef::wiki[]
 include::qm-cloud-init.adoc[]
 endif::wiki[]
 
 include::qm-cloud-init.adoc[]
 endif::wiki[]
 

+ifndef::wiki[]
+include::qm-pci-passthrough.adoc[]
+endif::wiki[]

 
 
 Managing Virtual Machines with `qm`
 
 
 Managing Virtual Machines with `qm`