x86, vmi: Mark VMI deprecated and schedule it for removal

Add text in feature-removal.txt indicating that VMI will be removed in
the 2.6.37 timeframe.

Signed-off-by: Alok N Kataria <[e-mail]>
Acked-by: Chris Wright <[e-mail]>
LKML-Reference: <[e-mail]>
[ removed a bogus Kconfig change, marked (DEPRECATED) in Kconfig ]
Signed-off-by: H. Peter Anvin <[e-mail]>
Signed-off-by: Ingo Molnar <[e-mail]>

Documentation/feature-removal-schedule.txt

···
 	will also allow making ALSA OSS emulation independent of
 	sound_core.  The dependency will be broken then too.
 Who:	Tejun Heo <[e-mail]>
+
+----------------------------
+
+What:	Support for VMware's guest paravirtuliazation technique [VMI] will be
+	dropped.
+When:	2.6.37 or earlier.
+Why:	With the recent innovations in CPU hardware acceleration technologies
+	from Intel and AMD, VMware ran a few experiments to compare these
+	techniques to guest paravirtualization technique on VMware's platform.
+	These hardware assisted virtualization techniques have outperformed the
+	performance benefits provided by VMI in most of the workloads. VMware
+	expects that these hardware features will be ubiquitous in a couple of
+	years, as a result, VMware has started a phased retirement of this
+	feature from the hypervisor. We will be removing this feature from the
+	Kernel too. Right now we are targeting 2.6.37 but can retire earlier if
+	technical reasons (read opportunity to remove major chunk of pvops)
+	arise.
+
+	Please note that VMI has always been an optimization and non-VMI kernels
+	still work fine on VMware's platform.
+	Latest versions of VMware's product which support VMI are,
+	Workstation 7.0 and VSphere 4.0 on ESX side, future maintainence
+	releases for these products will continue supporting VMI.
+
+	For more details about VMI retirement take a look at this,
+	http://blogs.vmware.com/guestosguide/2009/09/vmi-retirement.html
+
+Who:	Alok N Kataria <[e-mail]>
+
+----------------------------

arch/x86/Kconfig

···
 source "arch/x86/xen/Kconfig"
 
 config VMI
-	bool "VMI Guest support"
+	bool "VMI Guest support (DEPRECATED)"
 	select PARAVIRT
 	depends on X86_32
 	---help---
···
 	  (it could be used by other hypervisors in theory too, but is not
 	  at the moment), by linking the kernel to a GPL-ed ROM module
 	  provided by the hypervisor.
+
+	  As of September 2009, VMware has started a phased retirement
+	  of this feature from VMware's products. Please see
+	  feature-removal-schedule.txt for details.  If you are
+	  planning to enable this option, please note that you cannot
+	  live migrate a VMI enabled VM to a future VMware product,
+	  which doesn't support VMI. So if you expect your kernel to
+	  seamlessly migrate to newer VMware products, keep this
+	  disabled.
 
 config KVM_CLOCK
 	bool "KVM paravirtualized clock"

arch/x86/kernel/vmi_32.c

···
 
 	pv_info.paravirt_enabled = 1;
 	pv_info.kernel_rpl = kernel_cs & SEGMENT_RPL_MASK;
-	pv_info.name = "vmi";
+	pv_info.name = "vmi [deprecated]";
 
 	pv_init_ops.patch = vmi_patch;