There are still some other issues not addressed here, but it's a start.
Workarounds for false-positive reports:
- `RasterizerAccelerated`: Put a gigantic array behind a `unique_ptr`,
because UBSan has a [hardcoded limit](https://stackoverflow.com/questions/64531383/c-runtime-error-using-fsanitize-undefined-object-has-a-possibly-invalid-vp)
of how big it thinks objects can be, specifically when dealing with
offset-to-top values used with multiple inheritance. Hopefully this
doesn't have a performance impact.
- `QueryCacheBase::QueryCacheBase`: Avoid an operation that UBSan thinks
is UB even though it at least arguably isn't. See the link in the
comment for more information.
Fixes for correct reports:
- `PageTable`, `Memory`: Use `uintptr_t` values instead of pointers to
avoid UB from pointer overflow (when pointer arithmetic wraps around
the address space).
- `KScheduler::Reload`: `thread->GetOwnerProcess()` can be `nullptr`;
avoid calling methods on it in this case. (The existing code returns
a garbage reference to a field, which is then passed into
`LoadWatchpointArray`, and apparently it's never used, so it's
harmless in practice but still triggers UBSan.)
- `KAutoObject::Close`: This function calls `this->Destroy()`, which
overwrites the beginning of the object with junk (specifically a free
list pointer). Then it calls `this->UnregisterWithKernel()`. UBSan
complains about a type mismatch because the vtable has been
overwritten, and I believe this is indeed UB. `UnregisterWithKernel`
also loads `m_kernel` from the 'freed' object, which seems to be
technically safe (the overwriting doesn't extend as far as that
field), but seems dubious. Switch to a `static` method and load
`m_kernel` in advance.
[REUSE] is a specification that aims at making file copyright
information consistent, so that it can be both human and machine
readable. It basically requires that all files have a header containing
copyright and licensing information. When this isn't possible, like
when dealing with binary assets, generated files or embedded third-party
dependencies, it is permitted to insert copyright information in the
`.reuse/dep5` file.
Oh, and it also requires that all the licenses used in the project are
present in the `LICENSES` folder, that's why the diff is so huge.
This can be done automatically with `reuse download --all`.
The `reuse` tool also contains a handy subcommand that analyzes the
project and tells whether or not the project is (still) compliant,
`reuse lint`.
Following REUSE has a few advantages over the current approach:
- Copyright information is easy to access for users / downstream
- Files like `dist/license.md` do not need to exist anymore, as
`.reuse/dep5` is used instead
- `reuse lint` makes it easy to ensure that copyright information of
files like binary assets / images is always accurate and up to date
To add copyright information of files that didn't have it I looked up
who committed what and when, for each file. As yuzu contributors do not
have to sign a CLA or similar I couldn't assume that copyright ownership
was of the "yuzu Emulator Project", so I used the name and/or email of
the commit author instead.
[REUSE]: https://reuse.software
Follow-up to 01cf05bc75
This code was used to switch the CPU ID on thread switches.
However since "hle: kernel: multicore: Replace n-JITs impl. with 4 JITs.", the CPU ID is not a constant.
This has been dead code since this rewrite, and dropped in dynarmic as well. So there is no need to keep it.
This commit: Implements CPU Interrupts, Replaces Cycle Timing for Host
Timing, Reworks the Kernel's Scheduler, Introduce Idle State and
Suspended State, Recreates the bootmanager, Initializes Multicore
system.
Amends a few interfaces to be able to handle the migration over to the
new Memory class by passing the class by reference as a function
parameter where necessary.
Notably, within the filesystem services, this eliminates two ReadBlock()
calls by using the helper functions of HLERequestContext to do that for
us.
This was initially necessary when AArch64 JIT emulation was in its
infancy and all memory-related instructions weren't implemented.
Given the JIT now has all of these facilities implemented, we can remove
these functions from the CPU interface.
Our initialization process is a little wonky than one would expect when
it comes to code flow. We initialize the CPU last, as opposed to
hardware, where the CPU obviously needs to be first, otherwise nothing
else would work, and we have code that adds checks to get around this.
For example, in the page table setting code, we check to see if the
system is turned on before we even notify the CPU instances of a page
table switch. This results in dead code (at the moment), because the
only time a page table switch will occur is when the system is *not*
running, preventing the emulated CPU instances from being notified of a
page table switch in a convenient manner (technically the code path
could be taken, but we don't emulate the process creation svc handlers
yet).
This moves the threads creation into its own member function of the core
manager and restores a little order (and predictability) to our
initialization process.
Previously, in the multi-threaded cases, we'd kick off several threads
before even the main kernel process was created and ready to execute (gross!).
Now the initialization process is like so:
Initialization:
1. Timers
2. CPU
3. Kernel
4. Filesystem stuff (kind of gross, but can be amended trivially)
5. Applet stuff (ditto in terms of being kind of gross)
6. Main process (will be moved into the loading step in a following
change)
7. Telemetry (this should be initialized last in the future).
8. Services (4 and 5 should ideally be alongside this).
9. GDB (gross. Uses namespace scope state. Needs to be refactored into a
class or booted altogether).
10. Renderer
11. GPU (will also have its threads created in a separate step in a
following change).
Which... isn't *ideal* per-se, however getting rid of the wonky
intertwining of CPU state initialization out of this mix gets rid of
most of the footguns when it comes to our initialization process.
Internally within the kernel, it also includes a member variable for the
floating-point status register, and TPIDR, so we should do the same here to match
it.
While we're at it, also fix up the size of the struct and add a static
assertion to ensure it always stays the correct size.
