Group all the "guest OS" support options together, under
CONFIG_PARAVIRT. Make this a proper menu item so it looks neater on
menuconfig etc, and make the wording for each prompt uniform.
Signed-off-by: Rusty Russell <[email protected]>
diff -r 3d3ac181380b arch/i386/Kconfig
--- a/arch/i386/Kconfig Fri Sep 14 12:24:15 2007 +1000
+++ b/arch/i386/Kconfig Fri Sep 14 12:45:09 2007 +1000
@@ -214,28 +214,38 @@ config X86_ES7000
endchoice
-config PARAVIRT
- bool "Paravirtualization support (EXPERIMENTAL)"
+menuconfig PARAVIRT
+ bool "Paravirtualized guest support (EXPERIMENTAL)"
depends on EXPERIMENTAL
depends on !(X86_VISWS || X86_VOYAGER)
help
Paravirtualization is a way of running multiple instances of
Linux on the same machine, under a hypervisor. This option
changes the kernel so it can modify itself when it is run
under a hypervisor, improving performance significantly.
However, when run without a hypervisor the kernel is
theoretically slower. If in doubt, say N.
+
+if PARAVIRT
source "arch/i386/xen/Kconfig"
config VMI
- bool "VMI Paravirt-ops support"
- depends on PARAVIRT
+ bool "VMI Guest support"
help
VMI provides a paravirtualized interface to the VMware ESX server
(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.
+
+config LGUEST_GUEST
+ bool "Lguest guest support"
+ depends on !X86_PAE
+ help
+ Lguest is a tiny in-kernel hypervisor. Selecting this will
+ allow your kernel to boot under lguest. This option will increase
+ your kernel size by about 6k. If in doubt, say N.
+endif
config ACPI_SRAT
bool
diff -r 3d3ac181380b arch/i386/xen/Kconfig
--- a/arch/i386/xen/Kconfig Fri Sep 14 12:24:15 2007 +1000
+++ b/arch/i386/xen/Kconfig Fri Sep 14 12:37:38 2007 +1000
@@ -3,8 +3,8 @@
#
config XEN
- bool "Enable support for Xen hypervisor"
- depends on PARAVIRT && X86_CMPXCHG && X86_TSC && !NEED_MULTIPLE_NODES
+ bool "Xen guest support"
+ depends on X86_CMPXCHG && X86_TSC && !NEED_MULTIPLE_NODES
help
This is the Linux Xen port. Enabling this will allow the
kernel to boot in a paravirtualized environment under the
diff -r 3d3ac181380b drivers/lguest/Kconfig
--- a/drivers/lguest/Kconfig Fri Sep 14 12:24:15 2007 +1000
+++ b/drivers/lguest/Kconfig Fri Sep 14 12:31:44 2007 +1000
@@ -1,23 +1,18 @@ config LGUEST
config LGUEST
tristate "Linux hypervisor example code"
- depends on X86 && PARAVIRT && EXPERIMENTAL && !X86_PAE && FUTEX
- select LGUEST_GUEST
+ depends on X86 && EXPERIMENTAL && !X86_PAE && FUTEX
select HVC_DRIVER
---help---
- This is a very simple module which allows you to run
- multiple instances of the same Linux kernel, using the
+ This is a very simple module called lg.ko which allows you to run
+ multiple instances of the Linux kernel, using the
"lguest" command found in the Documentation/lguest directory.
Note that "lguest" is pronounced to rhyme with "fell quest",
not "rustyvisor". See Documentation/lguest/lguest.txt.
+ Usually you would also turn on "Lguest guest support", to create a
+ kernel which can also boot under lguest.
+
If unsure, say N. If curious, say M. If masochistic, say Y.
-
-config LGUEST_GUEST
- bool
- help
- The guest needs code built-in, even if the host has lguest
- support as a module. The drivers are tiny, so we build them
- in too.
config LGUEST_NET
tristate
We turn "Virtualization" into a menu, not a config option, since it's
actually only used as a menu. Then we move lguest under that menu.
Signed-off-by: Rusty Russell <[email protected]>
diff -r c2893801de2a drivers/Kconfig
--- a/drivers/Kconfig Fri Sep 14 13:24:46 2007 +1000
+++ b/drivers/Kconfig Fri Sep 14 13:24:49 2007 +1000
@@ -87,6 +87,4 @@ source "drivers/kvm/Kconfig"
source "drivers/kvm/Kconfig"
source "drivers/uio/Kconfig"
-
-source "drivers/lguest/Kconfig"
endmenu
diff -r c2893801de2a drivers/kvm/Kconfig
--- a/drivers/kvm/Kconfig Fri Sep 14 13:24:46 2007 +1000
+++ b/drivers/kvm/Kconfig Fri Sep 14 13:32:22 2007 +1000
@@ -1,21 +1,12 @@
#
# KVM configuration
#
-menuconfig VIRTUALIZATION
- bool "Virtualization"
+menu "Virtualization"
depends on X86
- default y
- ---help---
- Say Y here to get to see options for virtualization guest drivers.
- This option alone does not add any kernel code.
-
- If you say N, all options in this submenu will be skipped and disabled.
-
-if VIRTUALIZATION
config KVM
tristate "Kernel-based Virtual Machine (KVM) support"
- depends on X86 && EXPERIMENTAL
+ depends on EXPERIMENTAL
select ANON_INODES
---help---
Support hosting fully virtualized guest machines using hardware
@@ -45,4 +36,8 @@ config KVM_AMD
Provides support for KVM on AMD processors equipped with the AMD-V
(SVM) extensions.
-endif # VIRTUALIZATION
+# OK, it's a little counter-intuitive to do this, but it puts it neatly under
+# the virtualization menu.
+source drivers/lguest/Kconfig
+
+endmenu
It's pretty widely used, and the distributions will turn it on.
Signed-off-by: Rusty Russell <[email protected]>
diff -r b546335d7e75 arch/i386/Kconfig
--- a/arch/i386/Kconfig Fri Sep 14 13:24:49 2007 +1000
+++ b/arch/i386/Kconfig Fri Sep 14 13:27:13 2007 +1000
@@ -215,8 +215,8 @@ endchoice
endchoice
menuconfig PARAVIRT
- bool "Paravirtualized guest support (EXPERIMENTAL)"
- depends on EXPERIMENTAL
+ bool "Paravirtualized guest support"
+ default y
depends on !(X86_VISWS || X86_VOYAGER)
help
Paravirtualization is a way of running multiple instances of
@@ -224,7 +224,7 @@ menuconfig PARAVIRT
changes the kernel so it can modify itself when it is run
under a hypervisor, improving performance significantly.
However, when run without a hypervisor the kernel is
- theoretically slower. If in doubt, say N.
+ theoretically slower. If in doubt, say Y.
if PARAVIRT
On Fri, 14 Sep 2007 15:18:44 +1000 Rusty Russell wrote:
> We turn "Virtualization" into a menu, not a config option, since it's
> actually only used as a menu. Then we move lguest under that menu.
so you want to revert the 2007-july-16 merge that changes
menu -> menuconfig and makes most of the menus consistent in
presentation. I'd rather not, but I don't own it.
And Yes, lguest does need to be moved into a better location.
> Signed-off-by: Rusty Russell <[email protected]>
>
> diff -r c2893801de2a drivers/Kconfig
> --- a/drivers/Kconfig Fri Sep 14 13:24:46 2007 +1000
> +++ b/drivers/Kconfig Fri Sep 14 13:24:49 2007 +1000
> @@ -87,6 +87,4 @@ source "drivers/kvm/Kconfig"
> source "drivers/kvm/Kconfig"
>
> source "drivers/uio/Kconfig"
> -
> -source "drivers/lguest/Kconfig"
> endmenu
> diff -r c2893801de2a drivers/kvm/Kconfig
> --- a/drivers/kvm/Kconfig Fri Sep 14 13:24:46 2007 +1000
> +++ b/drivers/kvm/Kconfig Fri Sep 14 13:32:22 2007 +1000
> @@ -1,21 +1,12 @@
> #
> # KVM configuration
> #
> -menuconfig VIRTUALIZATION
> - bool "Virtualization"
> +menu "Virtualization"
> depends on X86
> - default y
> - ---help---
> - Say Y here to get to see options for virtualization guest drivers.
> - This option alone does not add any kernel code.
> -
> - If you say N, all options in this submenu will be skipped and disabled.
> -
> -if VIRTUALIZATION
>
> config KVM
> tristate "Kernel-based Virtual Machine (KVM) support"
> - depends on X86 && EXPERIMENTAL
> + depends on EXPERIMENTAL
> select ANON_INODES
> ---help---
> Support hosting fully virtualized guest machines using hardware
> @@ -45,4 +36,8 @@ config KVM_AMD
> Provides support for KVM on AMD processors equipped with the AMD-V
> (SVM) extensions.
>
> -endif # VIRTUALIZATION
> +# OK, it's a little counter-intuitive to do this, but it puts it neatly under
> +# the virtualization menu.
> +source drivers/lguest/Kconfig
> +
> +endmenu
---
~Randy
*** Remember to use Documentation/SubmitChecklist when testing your code ***
On Sep 14 2007 09:19, Randy Dunlap wrote:
>On Fri, 14 Sep 2007 15:18:44 +1000 Rusty Russell wrote:
>
>> We turn "Virtualization" into a menu, not a config option, since it's
>> actually only used as a menu. Then we move lguest under that menu.
Whatever, keep it as menuconfig. I want to disable it _at once_
without having to enter the menu, which is the primary motivation
having it as 'menuconfig'.
Jan
--
On Fri, 2007-09-14 at 09:19 -0700, Randy Dunlap wrote:
> On Fri, 14 Sep 2007 15:18:44 +1000 Rusty Russell wrote:
>
> > We turn "Virtualization" into a menu, not a config option, since it's
> > actually only used as a menu. Then we move lguest under that menu.
>
> so you want to revert the 2007-july-16 merge that changes
> menu -> menuconfig and makes most of the menus consistent in
> presentation. I'd rather not, but I don't own it.
Ok, I missed that one. To me it seems gratuitous to create a config
option simply to control a menu. However if that is considered the
Right Way, here is the "Just move lguest" variant.
> And Yes, lguest does need to be moved into a better location.
Indeed,
Rusty.
===
Move lguest under the virtualization menu.
Signed-off-by: Rusty Russell <[email protected]>
diff -r c2893801de2a drivers/Kconfig
--- a/drivers/Kconfig Fri Sep 14 13:24:46 2007 +1000
+++ b/drivers/Kconfig Fri Sep 14 13:24:49 2007 +1000
@@ -87,6 +87,4 @@ source "drivers/kvm/Kconfig"
source "drivers/kvm/Kconfig"
source "drivers/uio/Kconfig"
-
-source "drivers/lguest/Kconfig"
endmenu
diff -r c2893801de2a drivers/kvm/Kconfig
--- a/drivers/kvm/Kconfig Fri Sep 14 13:24:46 2007 +1000
+++ b/drivers/kvm/Kconfig Fri Sep 14 13:32:22 2007 +1000
@@ -45,4 +36,8 @@ config KVM_AMD
Provides support for KVM on AMD processors equipped with the AMD-V
(SVM) extensions.
-endif # VIRTUALIZATION
+# OK, it's a little counter-intuitive to do this, but it puts it neatly under
+# the virtualization menu.
+source drivers/lguest/Kconfig
+
+endif # VIRTUALIZATION
> We turn "Virtualization" into a menu, not a config option, since it's
> actually only used as a menu. Then we move lguest under that menu.
What about containerization bits ?
IPC_Namespaces, *_Namespaces - I think we should evaluate adding them
too to this menu.
--
-Alexey Eremenko "Technologov"
On Sat, 2007-09-15 at 11:49 +0300, Alexey Eremenko wrote:
> > We turn "Virtualization" into a menu, not a config option, since it's
> > actually only used as a menu. Then we move lguest under that menu.
>
> What about containerization bits ?
>
> IPC_Namespaces, *_Namespaces - I think we should evaluate adding them
> too to this menu.
Well, containerization deserves its own menu, but the question is does i
it belong under this menu?
Rusty.
Rusty Russell wrote:
> Well, containerization deserves its own menu, but the question is does i
> it belong under this menu?
No, I don't think so. While there are some broad similarities in
effect, the technology is completely different, as are the capabilities
and tradeoffs. They're pretty much orthogonal.
J
On Sun, 2007-09-16 at 07:56 -0700, Jeremy Fitzhardinge wrote:
> Rusty Russell wrote:
> > Well, containerization deserves its own menu, but the question is does i
> > it belong under this menu?
>
> No, I don't think so. While there are some broad similarities in
> effect, the technology is completely different, as are the capabilities
> and tradeoffs. They're pretty much orthogonal.
It seems to me containerization is much more similar a feature to SYSV
IPC, process accounting / auditing, and should be an option under
General setup, possibly with its own submenu. Nearly all the features
under general setup provide optional extensions to kernel services
available from userspace, and so it seems containerization falls
naturally into that category.
Virtualization is completely different, and probably needs separate
server (kvm, lguest) and client (kvm, lguest, xen, vmware) sections in
it's menu.
Zach
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Zachary Amsden wrote:
<snip>>
> Virtualization is completely different, and probably needs separate
> server (kvm, lguest) and client (kvm, lguest, xen, vmware) sections in
> it's menu.
So what is the differentiation between client and server above? Just
curious what makes kvm and lguest server and client.
>
> Zach
>
> _______________________________________________
> Virtualization mailing list
> [email protected]
> https://lists.linux-foundation.org/mailman/listinfo/virtualization
>
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Charles N Wyble wrote:
>
>
> Zachary Amsden wrote:
> <snip>>
> > Virtualization is completely different, and probably needs separate
> > server (kvm, lguest) and client (kvm, lguest, xen, vmware) sections in
> > it's menu.
>
>
> So what is the differentiation between client and server above? Just
> curious what makes kvm and lguest server and client.
"Host" and "guest" are better terms, I think. Kvm is all host, since
guests need no modification. lguest turns the kernel into both host and
guest. Xen Linux kernels are all guest, since the Xen hypervisor is the
host.
J
On Friday 14 September 2007 07:21, Rusty Russell wrote:
> It's pretty widely used,
Is it? By whom?
> and the distributions will turn it on.
That's no reason to make it default y. Please undo that. default y
is near always a bad idea.
Also I would still consider it experimental.
-Andi
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Andi Kleen wrote:
> On Friday 14 September 2007 07:21, Rusty Russell wrote:
>> It's pretty widely used,
>
> Is it? By whom?
>
>> and the distributions will turn it on.
>
> That's no reason to make it default y. Please undo that. default y
> is near always a bad idea.
Andi,
What do you base this on? Why is making something default y a bad idea?
Those most likely to care can turn it off. Is there a harmful effect
from leaving it on if its not being used?
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Jeremy Fitzhardinge wrote:
> Charles N Wyble wrote:
>>
>> Zachary Amsden wrote:
>> <snip>>
>>> Virtualization is completely different, and probably needs separate
>>> server (kvm, lguest) and client (kvm, lguest, xen, vmware) sections in
>>> it's menu.
>>
>> So what is the differentiation between client and server above? Just
>> curious what makes kvm and lguest server and client.
>
> "Host" and "guest" are better terms, I think. Kvm is all host, since
> guests need no modification. lguest turns the kernel into both host and
> guest. Xen Linux kernels are all guest, since the Xen hypervisor is the
> host.
>
> J
Ah ok. Thank you so much for the clarification. :)
>
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> Why is making something default y a bad idea?
> Those most likely to care can turn it off. Is there a harmful effect
> from leaving it on if its not being used?
Running yes "" | make oldconfig to upgrade kernel configs is standard practice
and you definitely don't want to have all kinds of random new unnecessary features
be turned on then.
Besides paravirt by itself is pretty useless; you need typically quite
complex other options set to do any meaningfull virtualization.
The only reason to use default y is in options that are not user visible
and have a reasonable default or things that cause direct boot failures
when upgrading old configurations. That all doesn't apply here.
Besides it's bad taste and taste is very important.
-Andi
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Andi Kleen wrote:
>
>> Why is making something default y a bad idea?
>> Those most likely to care can turn it off. Is there a harmful effect
>> from leaving it on if its not being used?
>
> Running yes "" | make oldconfig to upgrade kernel configs is standard practice
> and you definitely don't want to have all kinds of random new unnecessary features
> be turned on then.
Hmmmm. I disagree its a standard practice. I thought the whole point of
make oldconfig was to give you just the delta in configuration options
and was targeted at manual review?
Also how many people are building there own kernels these days?
Expanding on what I said in the original e-mail those who are likely to
care "CAN TURN IT OFF". Those who care about such things should be
REVIEWING CHANGES anyway. Thats what I do when looking at building
custom kernels. What changed that makes me want to move to a new version?
I generally try to stick with the distro kernel when possible, but part
of being an early and aggressive adopter of virtualization technology
involves running non distro kernels and patches.
Most people don't really care.
>
> Besides paravirt by itself is pretty useless; you need typically quite
> complex other options set to do any meaningfull virtualization.
Actually if I understand the functionality of paravirt correctly that is
not correct. I believe that will turn on the paravirt bits which allow
it to run under things such as VMI or Xen.
>
> The only reason to use default y is in options that are not user visible
> and have a reasonable default or things that cause direct boot failures
> when upgrading old configurations. That all doesn't apply here.
Again you need to think about the target audience here. A distro kernel
you don't have to worry about this stuff. A user compiling there own
kernel should already be able to handle this.
>
> Besides it's bad taste and taste is very important.
Well it's bad taste for you (one person). Taste is highly subjective. So
be careful in making broad ranging statements like this. :)
>
> -Andi
>
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> Actually if I understand the functionality of paravirt correctly that is
> not correct. I believe that will turn on the paravirt bits which allow
> it to run under things such as VMI or Xen.
You don't understand it correctly then.
-Andi
On Tue, 2007-09-18 at 12:57 +0200, Andi Kleen wrote:
> On Friday 14 September 2007 07:21, Rusty Russell wrote:
> > It's pretty widely used,
>
> Is it? By whom?
Hi Andi,
Please stop asking for facts! It's was easy claim to make, and hard to
disprove 8)
> > and the distributions will turn it on.
>
> That's no reason to make it default y. Please undo that. default y
> is near always a bad idea.
How about a "select" based on Xen, lguest or VMI? There's no other
reason to enable it, after all.
> Also I would still consider it experimental.
After 9 months in mainline and three kernel versions, I'd hope not.
It's been pretty damn stable (ok, you broke it once, but maybe that's
because you consider it experimental).
Cheers,
Rusty.
On Tuesday 18 September 2007 23:34, Rusty Russell wrote:
> On Tue, 2007-09-18 at 12:57 +0200, Andi Kleen wrote:
> > On Friday 14 September 2007 07:21, Rusty Russell wrote:
> > > It's pretty widely used,
> >
> > Is it? By whom?
>
> Hi Andi,
>
> Please stop asking for facts! It's was easy claim to make, and hard to
> disprove 8)
>
> > > and the distributions will turn it on.
> >
> > That's no reason to make it default y. Please undo that. default y
> > is near always a bad idea.
>
> How about a "select" based on Xen, lguest or VMI? There's no other
> reason to enable it, after all.
I did an patch to do that recently because the current setup
is indeed unobvious.
But I had to drop it again because
it ended up with Kconfig warnings. about undefined symbols
on x86-64. The problem is that lguest
is visible in Kconfig for all architectures and it warns
if you select something that doesn't exist on all architectures.
The only workaround would have been to define PARAVIRT
for all architectures, which I considered too ugly.
I think Sam stated recently he wanted to remove that warning
but it needed some infrastructure work.
> > Also I would still consider it experimental.
>
> After 9 months in mainline and three kernel versions,
Well it changed a lot each release.
> I'd hope not.
> It's been pretty damn stable (ok, you broke it once, but maybe that's
> because you consider it experimental).
Is there a significant user base?
At least the Xen port seems to have specific requirements
and essentially only work on xen-unstable (?) [or at least
some very new Xen version] which probably very few
people use.
-Andi
On Tue, 2007-09-18 at 23:52 +0200, Andi Kleen wrote:
> On Tuesday 18 September 2007 23:34, Rusty Russell wrote:
> > How about a "select" based on Xen, lguest or VMI? There's no other
> > reason to enable it, after all.
>
> I did an patch to do that recently because the current setup
> is indeed unobvious.
>
> But I had to drop it again because
> it ended up with Kconfig warnings. about undefined symbols
> on x86-64. The problem is that lguest
> is visible in Kconfig for all architectures and it warns
> if you select something that doesn't exist on all architectures.
I think that's fixed as a side-effect of this cleanup. At least, it
works for me on x86-64. Patch below: if you agree, I'll re-xmit all
three.
> > > Also I would still consider it experimental.
> >
> > After 9 months in mainline and three kernel versions,
>
> Well it changed a lot each release.
Well, the biggest change was the patching code getting enhanced in
2.6.22 (to cover all calls, not just 5). The 22 -> 23 changes were
fairly trivial.
So I think 2.6.24 is a reasonable time to remove EXPERIMENTAL.
> > I'd hope not.
> > It's been pretty damn stable (ok, you broke it once, but maybe that's
> > because you consider it experimental).
>
> Is there a significant user base?
It's enabled in Ubuntu Feisty (2.6.20).
> At least the Xen port seems to have specific requirements
> and essentially only work on xen-unstable (?) [or at least
> some very new Xen version] which probably very few
> people use.
Sure, and that might well still be experimental (Jeremy?). But that's
not CONFIG_PARAVIRT.
Hope that helps,
Rusty.
==
Andi points out that PARAVIRT is an option best selected when needed.
We introduce PARAVIRT_GUEST for the menu itself, and select PARAVIRT
if they ask for anything which needs it. This also makes PARAVIRT
non-experimental.
Signed-off-by: Rusty Russell <[email protected]>
diff -r 8efa5fdb22d8 arch/i386/Kconfig
--- a/arch/i386/Kconfig Wed Sep 19 11:23:18 2007 +1000
+++ b/arch/i386/Kconfig Wed Sep 19 11:33:59 2007 +1000
@@ -214,24 +214,30 @@ config X86_ES7000
endchoice
-menuconfig PARAVIRT
+config PARAVIRT
+ bool
+ depends on !(X86_VISWS || X86_VOYAGER)
+ help
+ This changes the kernel so it can modify itself when it is run
+ under a hypervisor, potentially improving performance significantly
+ over full virtualization. However, when run without a hypervisor
+ the kernel is theoretically slower and slightly larger.
+
+menuconfig PARAVIRT_GUEST
- bool "Paravirtualized guest support (EXPERIMENTAL)"
- depends on EXPERIMENTAL
+ bool "Paravirtualized guest support"
- depends on !(X86_VISWS || X86_VOYAGER)
- help
- Paravirtualization is a way of running multiple instances of
- Linux on the same machine, under a hypervisor. This option
- changes the kernel so it can modify itself when it is run
- under a hypervisor, improving performance significantly.
- However, when run without a hypervisor the kernel is
- theoretically slower. If in doubt, say N.
-
-if PARAVIRT
+ help
+ Say Y here to get to see options related to running Linux under
+ various hypervisors. This option alone does not add any kernel code.
+
+ If you say N, all options in this submenu will be skipped and disabled.
+
+if PARAVIRT_GUEST
source "arch/i386/xen/Kconfig"
config VMI
bool "VMI Guest support"
+ select PARAVIRT
help
VMI provides a paravirtualized interface to the VMware ESX server
(it could be used by other hypervisors in theory too, but is not
@@ -239,6 +246,7 @@ config VMI
config LGUEST_GUEST
bool "Lguest guest support"
+ select PARAVIRT
depends on !X86_PAE
help
Lguest is a tiny in-kernel hypervisor. Selecting this will
diff -r 8efa5fdb22d8 arch/i386/xen/Kconfig
--- a/arch/i386/xen/Kconfig Wed Sep 19 11:23:18 2007 +1000
+++ b/arch/i386/xen/Kconfig Wed Sep 19 11:25:07 2007 +1000
@@ -4,6 +4,7 @@
config XEN
bool "Xen guest support"
+ select PARAVIRT
depends on X86_CMPXCHG && X86_TSC && !NEED_MULTIPLE_NODES
help
This is the Linux Xen port. Enabling this will allow the
Andi Kleen wrote:
> At least the Xen port seems to have specific requirements
> and essentially only work on xen-unstable (?) [or at least
> some very new Xen version] which probably very few
> people use.
>
Only on 64-bit hosts, because of bugs in the 64-bit compat layer.
32-on-32 and 64-on-64 (when its done) should work fine.
BTW, what does "xm info" say on your system that fails? I'll try to put
a more graceful failure in there.
J
On 9/18/07, Charles N Wyble <[email protected]> wrote:
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>
> > "Host" and "guest" are better terms, I think. Kvm is all host, since
> > guests need no modification. lguest turns the kernel into both host and
> > guest. Xen Linux kernels are all guest, since the Xen hypervisor is the
> > host.
> >
Yes, I also prefer terms like "Host" and "Guest". Those terms are more
correct than "Server" and "Client", which are often reffered to
TCP/UDP port listening and network connection.
--
-Alexey Eremenko "Technologov"
On Tue, 2007-09-18 at 20:59 -0700, Jeremy Fitzhardinge wrote:
> Andi Kleen wrote:
> > At least the Xen port seems to have specific requirements
> > and essentially only work on xen-unstable (?) [or at least
> > some very new Xen version] which probably very few
> > people use.
> >
>
> Only on 64-bit hosts, because of bugs in the 64-bit compat layer.
> 32-on-32 and 64-on-64 (when its done) should work fine.
All the required fixes for 32on64 are queued for Xen 3.1.1 too. The
proposed updates are at
http://xenbits.xensource.com/xen-3.1-testing.pq.hg
Ian.
--
Ian Campbell
Current Noise: Detonation - Sword-Carved Skin
The executioner is, I hear, very expert, and my neck is very slender.
-- Anne Boleyn
On Tue, 18 Sep 2007, Charles N Wyble wrote:
>
> Andi Kleen wrote:
> >
> > Besides it's bad taste and taste is very important.
>
> Well it's bad taste for you (one person).
FWIW, my opinion is the same as Andi's here. Please, let's avoid this
disease -- unless *absolutely* required, stuff shouldn't be "default y".
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Satyam Sharma wrote:
>
> On Tue, 18 Sep 2007, Charles N Wyble wrote:
>> Andi Kleen wrote:
>>> Besides it's bad taste and taste is very important.
>> Well it's bad taste for you (one person).
>
> FWIW, my opinion is the same as Andi's here. Please, let's avoid this
> disease -- unless *absolutely* required, stuff shouldn't be "default y".
>
I am curious why you think it shouldn't be default why? Bad taste? Can
you provide data about how it will harm things?
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On Thu, 20 Sep 2007, Charles N Wyble wrote:
>
> Satyam Sharma wrote:
> >
> > On Tue, 18 Sep 2007, Charles N Wyble wrote:
> >> Andi Kleen wrote:
> >>> Besides it's bad taste and taste is very important.
> >> Well it's bad taste for you (one person).
> >
> > FWIW, my opinion is the same as Andi's here. Please, let's avoid this
> > disease -- unless *absolutely* required, stuff shouldn't be "default y".
>
> I am curious why you think it shouldn't be default why? Bad taste? Can
> you provide data about how it will harm things?
Clear CONFIG_PARAVIRT from your .config and try "make oldconfig", and find
out for yourself :-)
You'll end up having to answer questions for all other config options
below it, that you never cared about, that you didn't know even existed.
You'd obviously (I would, at least) feel annoyed by it all ... this is
almost a regression :-)
And for those who automate the oldconfig process using "yes", well, this
"default y" *will* end up introducing a kernel text size regression --
all those config options they never had earlier, suddenly got enabled.
Besides, like Andi said, selecting or enabling CONFIG_PARAVIRT is quite
pointless in the first place -- it's just a menuconfig symbol, not a
"real" kconfig symbol that _actually_ controls code in the Makefiles.
Satyam