Hello Everyone, As a preorder of the Pyra handheld, (OMAP5 SoC with 2x cortex-a15 arm cores) I'm against removing KVM host support for aarch32. I'm probably going to use this device for more than 5 years and thus the latest lts-kernel is no option for me.
Regards, Lukas Straub
Hi Lukas,
Thanks for your email.
On 2020-04-28 13:38, Lukas Straub wrote:
Hello Everyone, As a preorder of the Pyra handheld, (OMAP5 SoC with 2x cortex-a15 arm cores) I'm against removing KVM host support for aarch32. I'm probably going to use this device for more than 5 years and thus the latest lts-kernel is no option for me.
So let me spell it out. You are against the removal of a feature that you don't use yet, that you may of may not use on a device that doesn't exist yet, which you may or may not still be using by the time 5.4/5.6 aren't supported anymore. You don't seem to have the strongest case, I'm afraid.
But nothing is lost! The code is still in the git tree, ou can always revert the removal patches and revive the port if you are so inclined. It will just need to be stand-alone, and not depend on the arm64 code, which is now evolving its own separate way.
Cheers,
M.
Am Dienstag, den 28.04.2020, 14:30 +0100 schrieb Marc Zyngier:
Hi,
well, the PCBs are currently in production, the cases are already here (coating is currently being delayed as the company has closed down due to Corona right now), so the first 500 units would be ready to be shipped in around 2 - 3 months at latest.
The non-existance problem would therefore be solved then.
So far, AFAIK, the Letux team has tried their best to get as close to possible to mainline kernel and support as many classic devices (OMAP3 and OMAP4 devices as well), so removing 32bit support from mainline would surely be a step back for a lot of older devices as well.
I know we have to accept the decision, but so far, I've known Linux to support as many older devices as possible as well - removing KVM Host 32bit support would be a step back here.
Is there a specific reason for that? Is it too complex to maintain alongside the aarch64 KVM Host?
Hi Lukas,
Thanks for your email.
On 2020-04-28 13:38, Lukas Straub wrote:
Hello Everyone, As a preorder of the Pyra handheld, (OMAP5 SoC with 2x cortex-a15 arm cores) I'm against removing KVM host support for aarch32. I'm probably going to use this device for more than 5 years and thus the latest lts-kernel is no option for me.
So let me spell it out. You are against the removal of a feature that you don't use yet, that you may of may not use on a device that doesn't exist yet, which you may or may not still be using by the time 5.4/5.6 aren't supported anymore. You don't seem to have the strongest case, I'm afraid.
But nothing is lost! The code is still in the git tree, ou can always revert the removal patches and revive the port if you are so inclined. It will just need to be stand-alone, and not depend on the arm64 code, which is now evolving its own separate way.
Cheers,
M.
* Michael Mrozek EvilDragon@openpandora.org [200428 14:27]:
Am Dienstag, den 28.04.2020, 14:30 +0100 schrieb Marc Zyngier: I know we have to accept the decision, but so far, I've known Linux to support as many older devices as possible as well - removing KVM Host 32bit support would be a step back here.
Is there a specific reason for that? Is it too complex to maintain alongside the aarch64 KVM Host?
I don't know the details, but ideally things would be set up in a way where folks interested in patching 32-bit arm kvm support can do so without causing issues for 64-bit kvm development.
That being said, I don't know who might be interested in doing all the work for that. It's unrealistic to expect Marc to do this work if he's not using it.
Features that are used get more resources, and features that are less used end up just bitrotting into a broken state in about six weeks in the Linux kernel :)
Regards,
Tony
Michael,
On 2020-04-28 15:26, Michael Mrozek wrote:
Am Dienstag, den 28.04.2020, 14:30 +0100 schrieb Marc Zyngier:
Hi,
well, the PCBs are currently in production, the cases are already here (coating is currently being delayed as the company has closed down due to Corona right now), so the first 500 units would be ready to be shipped in around 2 - 3 months at latest.
The non-existance problem would therefore be solved then.
And then? Are these 500 machines going to be instantly turned into production KVM hosts? Over 7 years, we have identified at most *four* users. Four users over a few billion 32bit ARM devices running Linux. What are the odds that you will actually use KVM in any significant way? None whatsoever.
So far, AFAIK, the Letux team has tried their best to get as close to possible to mainline kernel and support as many classic devices (OMAP3 and OMAP4 devices as well), so removing 32bit support from mainline would surely be a step back for a lot of older devices as well.
Read the above. No users. Which means that KVM/arm is untested and is just bit-rotting. It is also incomplete and nobody is interested in putting the required effort to help it moving forward. Hell, the whole ARM port is now on life support, and you worry about KVM?
I know we have to accept the decision, but so far, I've known Linux to support as many older devices as possible as well - removing KVM Host 32bit support would be a step back here.
Linux is known to support as many *useful* devices and features as possible. KVM isn't one of them.
Is there a specific reason for that?
Please read the threads on the subject.
Is it too complex to maintain alongside the aarch64 KVM Host?
It certainly gets in the way of making significant changes to the arm64 port.
And as I said, feel free to revive the port anytime. The code is still there, the documentation available, and you're lucky enough to have one of the few machines capable of virtualization. If all of a sudden you end-up finding the killer use case for KVM/arm, I'll applaud its return. In the meantime, the arm64 will be able to move at a much faster pace. As it turns out, it has actual users.
Thanks,
M.
Hi Lukas,
Thanks for your email.
On 2020-04-28 13:38, Lukas Straub wrote:
Hello Everyone, As a preorder of the Pyra handheld, (OMAP5 SoC with 2x cortex-a15 arm cores) I'm against removing KVM host support for aarch32. I'm probably going to use this device for more than 5 years and thus the latest lts-kernel is no option for me.
So let me spell it out. You are against the removal of a feature that you don't use yet, that you may of may not use on a device that doesn't exist yet, which you may or may not still be using by the time 5.4/5.6 aren't supported anymore. You don't seem to have the strongest case, I'm afraid.
But nothing is lost! The code is still in the git tree, ou can always revert the removal patches and revive the port if you are so inclined. It will just need to be stand-alone, and not depend on the arm64 code, which is now evolving its own separate way.
Cheers,
M.-- Mit freundlichen Grüßen,
Michael Mrozek
OpenPandora GmbH Geschäftsführer: Michael Mrozek
Schäffbräustr. 11 85049 Ingolstadt Deutschland Tel.: 0841 / 990 5548 http://www.openpandora.de/ HRB 4879, Amtsgericht Ingolstadt
eMail: mrozek@openpandora.org
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Lukas Straub -
Marc Zyngier -
Michael Mrozek -
Tony Lindgren