Unify handling of UTCBs. The utcb of the main thread is with commit
ea38aad30e at a fixed location - per convention.
So we can remove all the ugly code to transfer the utcb address during process
creation.
To do so also the UTCB of the main thread of Core must be inside Genode's
thread context area to handle it the same way. Unfortunately the UTCB of the
main thread of Core can't be chosen, it is defined by the kernel.
Possible solutions:
- make virtual address of first thread UTCB configurable in hypervisor
- map the utcb of the first thread inside Core to the desired location
This commit implements the second option.
Kernel patch: make utcb map-able
With the patch the Utcb of the main thread of Core is map-able.
Fixes#374
Noux actually uses the sp variable during thread creation and expects to be
set accordingly. This wasn't the case for the main thread, it was ever set
to the address of the main thread UTCB.
Patch prevents following bugs:
* In sleep_forever the thread return from semaphore down if cap is revoked
during destruction of a thread. This causes an endless loop consuming time
not available for other threads.
* In lock_helper and cap_sel_alloc the thread return from the lock() method
even if the semaphore down call failed because of an revoked semaphore.
This lead to the situation that a thread subject to de-construction returns
from the lock method, but not holding the lock, entering the critical section
and modifying state inside the critical section. Another thread in parallel
already in the critical section or entering the critical section also
modifies the state. This lead to curious bugs ...
* thread_nova, thread_start, irq_session
Detect early bugs if the SM is gone unexpectedly where it should never
happen.
It now can hold a right bit used during IPC to demote rights of the to be
transfered capability.
The local_name field in the native_capability type is not needed anymore
in NOVA. Simplify the class, remove it from constructors and adapt all
invocations in base-nova.
Unfortunately local_name in struct Raw is still used in generic base code
(process.cc, reload_parent_cap.cc), however has no effect in base-nova.
Kernel patch:
Introduce a transfer item type to express that a cap should be translated
and if this fails to map it instead.
It would be possible without this combined transfer item type however
with additional overhead. In this case Genode/NOVA would
have to map and translate all caps used as parameter in IPC. It would look
like this:
* If the map and translation succeed, the cap at the new cap index
would have to be revoked. Then the translated cap index can be used.
* If the map succeeds and the translation fails then the mapped cap index
can be used.
* It would become complicated when multiple caps are mapped and translated
and only some of the translation succeed. In such cases Genode would have
to figure out the right relation of translated/mapped and not
translated/mapped caps. It would require to make some assumption about the
order how translated/mapped caps are reported at the UTCB by the kernel.
All the points above lead to the decision to create a separate transfer item
type for that.
Genode:
Most the times the translation succeeds, mapping of caps happens either
seldom. This takes now a bit the pressure of not enough aligned receive
cap windows as described in issue #247.
The patch mainly adds adjustments to handle the
translated and mapped caps correctly especially during freeing of the
receive window (don't free translated cap indexes).
Fixes#268
Check that there is enough room for a typed item on the
UTCB. Otherwise deny to add the item and return false.
Enable explicitly a return unused warning to get the right
attention.
Use git to get recent kernels from github. Adjust NOVA patch to compile
with recent github version. Patch and use makefile of NOVA microkernel
to avoid duplicated (and outdated) makefile in Genode
Furthermore, this patch adds support for using NOVA on x86_64. The
generic part of the syscall bindings has been moved to
'base-nova/include/nova/syscall-generic.h'. The 32/64-bit specific
parts are located at 'base-nova/include/32bit/nova/syscalls.h' and
'base-nova/include/64bit/nova/syscalls.h' respectively.
On x86_64, the run environment boots qemu using the Pulsar boot loader
because GRUB legacy does not support booting 64bit ELF executables.
In addition to the NOVA-specific changes in base-nova, this patch
rectifies compile-time warnings or build errors in the 'ports' and
'libports' repositories that are related to NOVA x86_64 (i.e., Vancouver
builds for 32bit only and needed an adaptation to NOVAs changed
bindings)
Fixes#233, fixes#234
