These instances were detected by searching for files that include
AK/StdLibExtras.h, but don't match the regex:
\\b(abs|AK_REPLACED_STD_NAMESPACE|array_size|ceil_div|clamp|exchange|for
ward|is_constant_evaluated|is_power_of_two|max|min|mix|move|_RawPtr|RawP
tr|round_up_to_power_of_two|swap|to_underlying)\\b
(Without the linebreaks.)
This regex is pessimistic, so there might be more files that don't
actually use any "extra stdlib" functions.
In theory, one might use LibCPP to detect things like this
automatically, but let's do this one step after another.
These instances were detected by searching for files that include
AK/Format.h, but don't match the regex:
\\b(CheckedFormatString|critical_dmesgln|dbgln|dbgln_if|dmesgln|FormatBu
ilder|__FormatIfSupported|FormatIfSupported|FormatParser|FormatString|Fo
rmattable|Formatter|__format_value|HasFormatter|max_format_arguments|out
|outln|set_debug_enabled|StandardFormatter|TypeErasedFormatParams|TypeEr
asedParameter|VariadicFormatParams|v_critical_dmesgln|vdbgln|vdmesgln|vf
ormat|vout|warn|warnln|warnln_if)\\b
(Without the linebreaks.)
This regex is pessimistic, so there might be more files that don't
actually use any formatting functions.
Observe that this revealed that Userland/Libraries/LibC/signal.cpp is
missing an include.
In theory, one might use LibCPP to detect things like this
automatically, but let's do this one step after another.
These instances were detected by searching for files that include
Kernel/Debug.h, but don't match the regex:
\\bdbgln_if\(|_DEBUG\\b
This regex is pessimistic, so there might be more files that don't check
for any real *_DEBUG macro. There seem to be no corner cases anyway.
In theory, one might use LibCPP to detect things like this
automatically, but let's do this one step after another.
This step would ideally not have been necessary (increases amount of
refactoring and templates necessary, which in turn increases build
times), but it gives us a couple of nice properties:
- SpinlockProtected inside Singleton (a very common combination) can now
obtain any lock rank just via the template parameter. It was not
previously possible to do this with SingletonInstanceCreator magic.
- SpinlockProtected's lock rank is now mandatory; this is the majority
of cases and allows us to see where we're still missing proper ranks.
- The type already informs us what lock rank a lock has, which aids code
readability and (possibly, if gdb cooperates) lock mismatch debugging.
- The rank of a lock can no longer be dynamic, which is not something we
wanted in the first place (or made use of). Locks randomly changing
their rank sounds like a disaster waiting to happen.
- In some places, we might be able to statically check that locks are
taken in the right order (with the right lock rank checking
implementation) as rank information is fully statically known.
This refactoring even more exposes the fact that Mutex has no lock rank
capabilites, which is not fixed here.
Using policy based design `SinglyLinkedList` and
`SinglyLinkedListWithCount` can be combined into one class which takes
a policy to determine how to keep track of the size of the list. The
default policy is to use list iteration to count the items in the list
each time. The `WithCount` form is a different policy which tracks the
size, but comes with the overhead of storing the count and
incrementing/decrementing on each modification.
This model is extensible to have other forms of counting by
implementing only a new policy instead of implementing a totally new
type.
These instances were detected by searching for files that include
Array.h, but don't match the regex:
\\b(Array(?!\.h>)|iota_array|integer_sequence_generate_array)\\b
These are the three symbols defined by Array.h.
In theory, one might use LibCPP to detect things like this
automatically, but let's do this one step after another.
If a page fault occurs while interrupts are disabled, we were wrongly
enabling interrupts right away in the page fault handler.
Instead, we should only do this if interrupts were enabled when the
page fault occurred.
We were already handling the rmdir("..") case by refusing to remove
directories that were not empty.
This patch removes a FIXME from January 2019 and adds a test. :^)
Dr. POSIX says that we should reject attempts to rmdir() the file named
"." so this patch does exactly that. We also add a test.
This solves a FIXME from January 2019. :^)
This has been done in multiple ways:
- Each time we modeset the resolution via the VirtIOGPU DisplayConnector
we ensure that the framebuffer is updated with the new resolution.
- Each time the cursor is updated we ensure that the framebuffer console
is marked dirty so the IO Work Queue task which is scheduled to check
if it is dirty, will flush the surface.
- We only initialize a framebuffer console after we ensure that at the
very least a DisplayConnector has being set with a known resolution.
- We only call GenericFramebufferConsole::enable() when enabling the
console after the important variables of the console (m_width, m_pitch
and m_height) have been set.
Check if the process we are currently running is in a jail, and if that
is the case, fail early with the EPERM error code.
Also, as Brian noted, we should also disallow attaching to a jail in
case of already running within a setid executable, as this leaves the
user with false thinking of being secure (because you can't exec new
setid binaries), but the current program is still marked setid, which
means that at the very least we gained permissions while we didn't
expect it, so let's block it.
The hand-written assembly does not compile under Clang due to register
size mismatches. Using a loop is slower (~6 instructions on O2 as
opposed to 2 with hand-written assembly), but using the pause
instruction makes this more efficient even under TCG.
For pause we use isb sy which will put the processor to sleep while the
pipeline is being flushed. This instruction is also used by Rust in spin
loops and found to be more efficient, as well as being a rough
equivalent to the x86 pause instruction which we also use here.
For wait_check we use yield, which is a hinted nop that is faster to
execute, and I leave a FIXME for processing SMP messages once we support
SMP.
These two changes probably make spin loops work on aarch64 :^)
This commit changes the init.cpp file to start and initialize the
Scheduler, and actually runs init_stage2. To show that it actually
works, another thread is spawned and executed simultaneously, by context
switching between the two!
This requires two new functions, context_first_init and
restore_context_and_eret. With this code in place, we are now running
the first idle thread! :^)
This changes the stack pointer to the initial_thread stack pointer, and
pushes two pointers onto the stack that point to the initial_thread. The
function then jumps to the ip of the initial_thread, which will be
thread_context_first_enter, and hangs there because that function is not
yet implemented.
This does not handle everything correctly yet, such as setting the
correct state for running userspace applications, however this should be
enough to get kernel scheduling to work.
These are architecture-specific anyway, so they belong in the Arch
directory. This commit also adds ThreadRegisters::set_initial_state to
factor out the logic in Thread.cpp.
I can't think of a reason why copying the Processor class makes sense,
so lets make sure it's not possible to do it by accident by declaring
the copy constructor as deleted.
This removes the x86 specific hlt instruction from the scheduler, and
allows us to run the scheduler code for aarch64 by implementing
Processor::wait_for_interrupt for aarch64.
This file does not contain any architecture specific implementations,
so we can move it to the Kernel base directory. Also update the relevant
include paths.
We are actually storing tpidr_el0, as can be seen in vector_table.S, but
the RegisterState.h incorrectly had tpidr_el1. This will probably save
some annoying debugging later on.
