Project Description
The Steam Deck is a portable gaming handheld built around platform technology similar to the one found in AMD mobile laptops. Vendor Valve ships a custom Linux distribution with downstream patches on this device, but booting into other distributions is possible. Connecting the Steam Deck to a dock can turn it into a compact workstation.
While a lot of patches have been upstreamed or rewritten for upstream, some upstream-only issues persist. Archlinux users work around this by just using Valve's downstream versions which is not the route I would like to take.
I already had a chance to explore these issues last year and got a lot of help from cool developers such as tiwai. But I did not get as far as I would have liked. I want to revisit these issues and learn more about kernel work. As a kernel newbie I am looking forward to learning more.
I appreciate help, pointers, tips and tricks from experienced maintainers. Kernel newbies such as myself are also very welcome to join, too. Some open issues already contain commands that you can use to collect information and help you learn, so make sure to take a look at the existing Bugzilla reports.
Goal for this Hackweek
- retest known issues with the latest Tumbleweed snapshot
- figure out how to collect useful information and research around drivers
- revive these open issues and hopefully come closer to finding a solution
- learn a bunch about the kernel, drivers and debugging (probably mostly ALSA ASoC, DRM, x86_64 ACPI)
- try patching the Tumbleweed kernel and see what happens
- write a small blog post about how it went including some photos
Resources
- Currently open issues: https://bugzilla.opensuse.org/buglist.cgi?quicksearch=steam+deck
- Valve hosts their source code as src.tar.gz containing bare git repos: https://steamdeck-packages.steamos.cloud/archlinux-mirror/sources/jupiter-main/
This project is part of:
Hack Week 22
Activity
Comments
Similar Projects
Improve various phones kernel mainline support (Qualcomm, Exynos, MediaTek) by pvorel
Similar to previous hackweeks ( https://hackweek.opensuse.org/projects/improve-qualcomm-soc-msm8994-slash-msm8992-kernel-mainline-support, https://hackweek.opensuse.org/projects/test-mainline-kernel-on-an-older-qualcomm-soc-msm89xx-explore-mainline-kernel-qualcomm-mainlining) try to improve kernel mainline support of various phones.
Improve UML page fault handler by ptesarik
Description
Improve UML handling of segmentation faults in kernel mode. Although such page faults are generally caused by a kernel bug, it is annoying if they cause an infinite loop, or panic the kernel. More importantly, a robust implementation allows to write KUnit tests for various guard pages, preventing potential kernel self-protection regressions.
Goals
Convert the UML page fault handler to use oops_* helpers, go through a few review rounds and finally get my patch series merged in 6.14.
Resources
Wrong initial attempt: https://lore.kernel.org/lkml/20231215121431.680-1-petrtesarik@huaweicloud.com/T/
Create DRM drivers for VESA and EFI framebuffers by tdz
Description
We already have simpledrm for firmware framebuffers. But the driver is originally for ARM boards, not PCs. It is already overloaded with code to support both use cases. At the same time it is missing possible features for VESA and EFI, such as palette modes or EDID support. We should have DRM drivers for VESA and EFI interfaces. The infrastructure exists already and initial drivers can be forked from simpledrm.
Goals
- Initially, a bare driver for VESA or EFI should be created. It can take functionality from simpledrm.
- Then we can begin to add additional features. The boot loader can provide EDID data. With VGA hardware, VESA can support paletted modes or color management. Example code exists in vesafb.
Contributing to Linux Kernel security by pperego
Description
A couple of weeks ago, I found this blog post by Gustavo Silva, a Linux Kernel contributor.
I always strived to start again into hacking the Linux Kernel, so I asked Coverity scan dashboard access and I want to contribute to Linux Kernel by fixing some minor issues.
I want also to create a Linux Kernel fuzzing lab using qemu and syzkaller
Goals
- Fix at least 2 security bugs
- Create the fuzzing lab and having it running
The story so far
- Day 1: setting up a virtual machine for kernel development using Tumbleweed. Reading a lot of documentation, taking confidence with Coverity dashboard and with procedures to submit a kernel patch
- Day 2: I read really a lot of documentation and I triaged some findings on Coverity SAST dashboard. I have to confirm that SAST tool are great false positives generator, even for low hanging fruits.
- Day 3: Working on trivial changes after I read this blog post:
https://www.toblux.com/posts/2024/02/linux-kernel-patches.html. I have to take confidence
with the patch preparation and submit process yet.
- First trivial patch sent: using strtruefalse() macro instead of hard-coded strings in a staging driver for a lcd display
- Fix for a dereference before null check issue discovered by Coverity (CID 1601566) https://scan7.scan.coverity.com/#/project-view/52110/11354?selectedIssue=1601566
- Day 4: Triaging more issues found by Coverity.
- The patch for CID 1601566 was refused. The check against the NULL pointer was pointless so I prepared a version 2 of the patch removing the check.
- Fixed another dereference before NULL check in iwlmvmparsewowlaninfo_notif() routine (CID 1601547). This one was already submitted by another kernel hacker :(
- Day 5: Wrapping up. I had to do some minor rework on patch for CID 1601566. I found a stalker bothering me in private emails and people I interacted with me, advised he is a well known bothering person. Markus Elfring for the record.
Wrapping up: being back doing kernel hacking is amazing and I don't want to stop it. My battery pack is completely drained but changing the scope gave me a great twist and I really want to feel this energy not doing a single task for months.
I failed in setting up a fuzzing lab but I was too optimistic for the patch submission process.
The patches
Modernize ocfs2 by goldwynr
Ocfs2 has gone into a stage of neglect and disrepair. Modernize the code to generate enough interest.
Goals: * Change the mount sequence to use fscontext * Move from using bufferhead to bio/folios * Use iomap * Run it through xfstests
Create DRM drivers for VESA and EFI framebuffers by tdz
Description
We already have simpledrm for firmware framebuffers. But the driver is originally for ARM boards, not PCs. It is already overloaded with code to support both use cases. At the same time it is missing possible features for VESA and EFI, such as palette modes or EDID support. We should have DRM drivers for VESA and EFI interfaces. The infrastructure exists already and initial drivers can be forked from simpledrm.
Goals
- Initially, a bare driver for VESA or EFI should be created. It can take functionality from simpledrm.
- Then we can begin to add additional features. The boot loader can provide EDID data. With VGA hardware, VESA can support paletted modes or color management. Example code exists in vesafb.
Create a DRM driver for VGA video cards by tdz
Yes, those VGA video cards. The goal of this project is to implement a DRM graphics driver for such devices. While actual hardware is hard to obtain or even run today, qemu emulates VGA output.
VGA has a number of limitations, which make this project interesting.
- There are only 640x480 pixels (or less) on the screen. That resolution is also a soft lower limit imposed by DRM. It's mostly a problem for desktop environments though.
- Desktop environments assume 16 million colors, but there are only 16 colors with VGA. VGA's 256 color palette is not available at 640x480. We can choose those 16 colors freely. The interesting part is how to choose them. We have to build a palette for the displayed frame and map each color to one of the palette's 16 entries. This is called dithering, and VGA's limitations are a good opportunity to learn about dithering algorithms.
- VGA has an interesting memory layout. Most graphics devices use linear framebuffers, which store the pixels byte by byte. VGA uses 4 bitplanes instead. Plane 0 holds all bits 0 of all pixels. Plane 1 holds all bits 1 of all pixels, and so on.
The driver will probably not be useful to many people. But, if finished, it can serve as test environment for low-level hardware. There's some interest in supporting old Amiga and Atari framebuffers in DRM. Those systems have similar limitations as VGA, but are harder to obtain and test with. With qemu, the VGA driver could fill this gap.
Apart from the Wikipedia entry, good resources on VGA are at osdev.net and FreeVGA