Former Nouveau Lead Developer Joins NVIDIA, Continues Working On Open-Source Driver

[oiaohm]

on the contrary. its the nouveau open source driver that will support the closed source userspace aswell as mesa and nvk.

rest of your assumptions will be wrong in the end.

That going to require Nvidia getting over their no implicit sync point of view as well. nouveau does support implicit sync where Nvidia own driver does not and this is intentional choice by Nvidia..

[arabek]

vulkan mandates explicit sync with the new extension wich is going to be supported in 560 according to github issue so that's also almost in the past.

[oiaohm]

vulkan mandates explicit sync with the new extension wich is going to be supported in 560 according to github issue so that's also almost in the past.

This is mistake. Used to ignore the requirements of the Linux platform. It really simple to miss that not everyone is going to run their system graphical. arabek when using a Linux tty as in the text base mode does Vulkan apply the answer is no it does not.

There are many places where the driver need to either provided implciit sync itself or allow the Linux kernel implementation implicit sync on top it the driver explicit sync to exist that will then proceed to show implicit sync to applications.

arabek Linus rule. "Don't break userspace." Nvidia driver not provide kernel mode implicit sync means it does break userspace.

https://www.collabora.com/news-and-blog/blog/2022/06/09/bridging-the-synchronization-gap-on-linux/

Yes this write up missed that not having a implicit sync mode does break userspace.

Arabek another when the fbdev emulation on top of DRI in the Linux work works it also need implicit sync. Mainline Linux kernel graphics drivers have implicit sync in kernel support because it need to be able to provide all the syscalls the Linux kernel supports.

Vulkan is surface level window dressing.

By the way it been a long term problem with use of Nvidia switching between text mode terminal and graphical having the complete thing kernel panic. Guess why. Yep lack of kernel mode implicit sync to keep swap between in order.

[mdedetrich]

This sentence doesn't work at all if I insert Valve into it.

The difference is, Nvidia just sits back with their hand out gimme gimme gimme. What did Valve do? Linux wasn't nearly ready for gaming as it is today. Valve contributed.

Nvidia could have contributed.

NVidia did contribute, they were one of the primary contributors for explicit sync

[arabek]

arabek Linus rule. "Don't break userspace." Nvidia driver not provide kernel mode implicit sync means it does break userspace.

(…)

By the way it been a long term problem with use of Nvidia switching between text mode terminal and graphical having the complete thing kernel panic. Guess why. Yep lack of kernel mode implicit sync to keep swap between in order.

You're still assuming they're going to keep the closed source kernel driver for time to come. GL;HF trolling the community here. I'm done.

[oiaohm]

You're still assuming, they're going to keep the closed source kernel driver for time to come. GL;HF trolling the community here. I'm done.

No you are assuming that Nouveau and https://github.com/NVIDIA/open-gpu-kernel-modules/ will merge.

There is difference in options on stuff between open source Nouveau and Open source Nvidia made kernel module developers.

I did not say Nvidia would be keeping closed source kernel driver around if you read careful.

The key thing here is Nouveau is a "Mainline Linux kernel graphics driver" but Nvidia open source offering so far is not.

Not being mainline has effects of particular Linux kernel rules not being applied.

https://www.phoronix.com/news/Intel-i915-Versioned-Firmware

There are examples like above where Intel/AMD/ARM/Nouveau have been blocked from doing particular things because they are against Linux kernel development rules because they are mainline.

arabek is a serous risk the way Nvidia core driver developers like to make their driver will never be Linux kernel mainline compatible. So strong chance we stay at the status quo with Nouveau and NVIDIA "open-gpu-kernel-modules" being two different things. Also notice that Mesa userspace drivers normally don't force a particular kernel/driver version where Nvidia developers are use to making their userspace fail if the versions don't match.

There are a lot of things that Nvidia developers will have to get over and accept if they wish to merge down to Nouveau being the only driver. Remember lot of the rules/restrictions on Nouveau don't come from Nouveau developers but are instead core linux kernel development rules.

arebek I just see what you have been doing is posting wishful thinking. It would be nice of Nouveau comes the only driver but we cannot be sure of this ever happening due to the requirement that the Nvidia driver developers will have to accept the Linux kernel development rules for that to happen.

This includes getting over total anti Implicit sync stand. Sorting out a stable ABI between firmware and kernel so that the kernel driver can use multi versions of the Linux kernel project firmware updates. Sorting out stable ABI between kernel space and userspace for the userspace drivers of Nvidia to use. None of this is going to be fast if it happens at all. amd with the amdgpu progress back in the day with the same problems gives this a timeline of about 4 years at best with never at worst.

[arabek]

No you are assuming that Nouveau and https://github.com/NVIDIA/open-gpu-kernel-modules/ will merge.

No, they won't. You're assuming. They don't have to. Nvidia just has to enable it's closed source userspace to work with Nouveu now. And it's just around the corner.

[oiaohm]

No, they won't. You're assuming. They don't have to. Nvidia just has to enable it's closed source userspace to work with Nouveu now. And it's just around the corner.

https://lwn.net/Articles/910343/

arabek the reality is there are different known problems that were documented over time. Like the Nvidia firmware lack of stable ABI problem.

Nouveu is going to lag supporting new cards because it will not be just push out a firmware to make older Nouveu driver work with new card.

AMD and Intel can push out a updated firmware to make more cards work and have that work the older kernels because they do have mostly stable ABI between kernel and firmware.

The issues Nvidia has to over come means solution is not just around the corner. AMD when their aquired ATI had to overcome the same problems leading up to AMDGPU driver.

arabek there is problem here. The windows driver the firmware and os driver being locked with each other is fine so no ABI here not a problem. Linux mainline drivers are just a different beast. Think about it mainline kernel is shipped out to distributions this could be 2 years old effectively and a user is attempting to use a new card how are you going to make this work. AMD and Intel have a solution the firmware and fireware ABI. Where is Nvidia right now with this problem.

Not using mainline driver allows keeping the windows behavior of firmware and driver locked to each other.

[ezst036]

NVidia did contribute, they were one of the primary contributors for explicit sync

To my knowledge, Valve did that.

https://www.phoronix.com/news/Mesa-24.1-Vulkan-Wayland-Exp

Joshua Ashton with Valve authored Mesa's wsi: Implement explicit sync for Wayland merge request that introduces this support.

[mdedetrich]

To my knowledge, Valve did that.

https://www.phoronix.com/news/Mesa-24.1-Vulkan-Wayland-Exp

Yes for Vulkan specifically however due to the nature of how the linux graphics stack works, explicit sync needs to be added in many parts of the system and Erik made a significant amount if work in the core Wayland protocol.