This matches x86_64's behaviour in common_trap_exit. (called from
thread_context_first_enter)
Currently thread_context_first_enter is only called when creating new
processes from scratch, in which case this doesn't change the actual
behaviour. But once thread_context_first_enter is called as part of
execve support, this will ensure the Thread's m_current_trap is set
correctly to the new trap frame.
When we execute in userspace, the exception level is EL0, so to handle
exceptions, such as interrupts, and syscalls, we need to add handlers to
vector_table.S. For now we only support running userspace applications
in AArch64 mode, so this commit only adds the handlers for that mode.
Until now the kernel was always executing with SP_EL0, as this made the
initial dropping to EL1 a bit easier. This commit changes this behaviour
to use the corresponding SP_ELx for each exception level.
To make sure that the execution of the C++ code can continue, the
current stack pointer is copied into the corresponding SP_ELx just
before dropping an exception level.
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! :^)
As there is no need for a Prekernel on aarch64, the Prekernel code was
moved into Kernel itself. The functionality remains the same.
SERENITY_KERNEL_AND_INITRD in run.sh specifies a kernel and an inital
ramdisk to be used by the emulator. This is needed because aarch64
does not need a Prekernel and the other ones do.
2022-03-12 14:54:12 -08:00
Renamed from Kernel/Prekernel/Arch/aarch64/vector_table.S (Browse further)