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0 pointschousuke5y ago0 comments

It's a theoretical problem. The window-management parts of sway are tiny and having them in the same process means you don't have to do IPC every time your windows do something. That simplicity means it's easier to write code that doesn't crash.

Most of the heavy-lifting is done in wlroots anyway. wlroots based compositors really do implement just their own flavour of compositing what you see on the screen on top.

That said, you still can use IPC, if you really want to; I have an external window manager that augments Sway's tiling system via its i3-compatible IPC mechanism to arrange my windows in a way that Sway doesn't do natively. If you really wanted to, there's nothing stopping you from writing a wayland compositor that uses an external window manager.

At any rate, I don't buy the reliability argument at all. I've used sway since 0.10 or something, and I only ever remember crashing it once, and I fixed that bug myself. :P

0 pointschousuke5y ago0 comments

Most of the heavy-lifting is done in wlroots anyway. wlroots based compositors really do implement just their own flavour of compositing what you see on the screen on top.

At any rate, I don't buy the reliability argument at all. I've used sway since 0.10 or something, and I only ever remember crashing it once, and I fixed that bug myself. :P

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3 comments · 1 top-level

jude-5y ago· 2 in thread

I'd say it's a very practical problem. Why put N different things that used to run in separate protection domains into the same protection domain? Have we gotten N times better at writing code that doesn't crash? Do we believe that we can put N different things into the same address space but somehow ensure that a security hole in one of them won't compromise all of them? Have computers gotten so slow in the last 30 years that doing IPC is no longer an option?

I'm glad that you have personally not encountered a crash in Sway -- I really, truly am. But let's not pretend that a data point of 1 indicates a trend.

cycloptic5y ago

In practice, placing everything in one process seems to reduce the total attack surface. There is quite a lot of code required to synchronize state between the X server, window manager and compositor. When you combine them, you can throw out most of those bits that are largely serialization/deserialization.

jude-5y ago

> In practice, placing everything in one process seems to reduce the total attack surface.

Surely you're joking. Privilege separation [1] is a thing for a reason.

If we believed that putting different things into the same address space made them more secure, then why stop there? Why not just put the kernel, the shell, X11, your HTTP server, and everything else into the same address space? Let's just do away with processes -- let all schedulable units be threads that can all read and write to each other's memory, because what could possibly go wrong? /s

[1] https://en.wikipedia.org/wiki/Privilege_separation

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