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authorMarcel Ziswiler <marcel.ziswiler@toradex.com>2020-05-19 23:01:26 +0200
committerMarcel Ziswiler <marcel.ziswiler@toradex.com>2020-05-19 23:37:01 +0200
commit2ae782ca839e0ee07de37122ddea362adff2e975 (patch)
treedf6b1a190760f51465122ca4c13492d5ac5984c6 /Documentation/virtual/kvm/api.txt
parent0a8ab17689e628c84a666195bfc6ab85d11cf057 (diff)
parent0661b3d6cfd774e28a2e2ba90a3d87479e5c399b (diff)
Merge tag 'v4.9.220' into 4.9-2.3.x-imx
This is the 4.9.220 stable release Conflicts: arch/arm/Kconfig.debug arch/arm/boot/dts/imx7s.dtsi arch/arm/mach-imx/common.h arch/arm/mach-imx/cpuidle-imx6q.c arch/arm/mach-imx/cpuidle-imx6sx.c arch/arm/mach-imx/suspend-imx6.S block/blk-core.c drivers/crypto/caam/caamalg.c drivers/crypto/mxs-dcp.c drivers/dma/imx-sdma.c drivers/gpu/drm/bridge/adv7511/adv7511_drv.c drivers/input/keyboard/imx_keypad.c drivers/input/keyboard/snvs_pwrkey.c drivers/mmc/host/sdhci.c drivers/net/can/flexcan.c drivers/net/ethernet/freescale/fec_main.c drivers/net/phy/phy_device.c drivers/net/wireless/ath/ath10k/pci.c drivers/tty/serial/imx.c drivers/usb/dwc3/gadget.c drivers/usb/host/xhci.c include/linux/blkdev.h include/linux/cpu.h include/linux/platform_data/dma-imx-sdma.h kernel/cpu.c net/wireless/util.c sound/soc/fsl/Kconfig sound/soc/fsl/fsl_esai.c sound/soc/fsl/fsl_sai.c sound/soc/fsl/imx-sgtl5000.c
Diffstat (limited to 'Documentation/virtual/kvm/api.txt')
-rw-r--r--Documentation/virtual/kvm/api.txt16
1 files changed, 11 insertions, 5 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index 3ff58a8ffabb..d1908e50b506 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -13,7 +13,7 @@ of a virtual machine. The ioctls belong to three classes
- VM ioctls: These query and set attributes that affect an entire virtual
machine, for example memory layout. In addition a VM ioctl is used to
- create virtual cpus (vcpus).
+ create virtual cpus (vcpus) and devices.
Only run VM ioctls from the same process (address space) that was used
to create the VM.
@@ -24,6 +24,11 @@ of a virtual machine. The ioctls belong to three classes
Only run vcpu ioctls from the same thread that was used to create the
vcpu.
+ - device ioctls: These query and set attributes that control the operation
+ of a single device.
+
+ device ioctls must be issued from the same process (address space) that
+ was used to create the VM.
2. File descriptors
-------------------
@@ -32,10 +37,11 @@ The kvm API is centered around file descriptors. An initial
open("/dev/kvm") obtains a handle to the kvm subsystem; this handle
can be used to issue system ioctls. A KVM_CREATE_VM ioctl on this
handle will create a VM file descriptor which can be used to issue VM
-ioctls. A KVM_CREATE_VCPU ioctl on a VM fd will create a virtual cpu
-and return a file descriptor pointing to it. Finally, ioctls on a vcpu
-fd can be used to control the vcpu, including the important task of
-actually running guest code.
+ioctls. A KVM_CREATE_VCPU or KVM_CREATE_DEVICE ioctl on a VM fd will
+create a virtual cpu or device and return a file descriptor pointing to
+the new resource. Finally, ioctls on a vcpu or device fd can be used
+to control the vcpu or device. For vcpus, this includes the important
+task of actually running guest code.
In general file descriptors can be migrated among processes by means
of fork() and the SCM_RIGHTS facility of unix domain socket. These