diminished takes two caps and asserts that one is equal to the other
except that one may have fewer rights. We remove this definition and all
references to it, replacing diminished with equality.
Prior to this commit the kernel would always trigger a full reschedule
on setPriority. This change allows the kernel to attempt a direct
switch, avoiding invoking the scheduler.
Fixes a case where a thread can go from Running->Inactive->Restart and
use a restart PC that is out of date. An out of date restart PC occurs
when a thread was transitioned to running after being in a blocked
state, but was never scheduled and so did not execute the traps code
that updates the restart PC.
This also renames relevant register names for consistency across
architectures (FaultIP and NextIP).
arm ainvs: cleanup
Abbreviate Hoare triples that do not care about the return value and
whose pre and post conditions are the same.
x64 ainvs: cleanup
ainvs: cleanup
x64 ainvs: cleanup
drefine: cleanup
A lot of the proofs in SysInit and DRefine previously had to unfold opt_object,
which was really just an alias for cdl_objects with the arguments in the
opposite order! This commit deletes opt_object in favour of using cdl_objects
directly, which should slightly reduce the burden of unfolding.
Session-qualified imports will be required for Isabelle2018 and help clarify
the structure of sessions in the build tree.
This commit mainly adds a new set of sessions for lib/, including a Lib
session that includes most theories in lib/ and a few separate sessions for
parts that have dependencies beyond CParser or are separate AFP sessions.
The group "lib" collects all lib/ sessions.
As a consequence, other theories should use lib/ theories by session name,
not by path, which in turns means spec and proof sessions should also refer
to each other by session name, not path, to avoid duplicate theory errors in
theory merges later.
While the numerical value is arch dependent, the definition and symbolic value
are not. This commit factors out the symbolic computation and only unfolds the
numeric value in the architecture dependent spec.
A handle of fiddly proofs change slightly. A common offender involves
tcb_cap_cases, which should be unfolded with the ran_tcb_cap_cases
rule where possible rather than with tcb_cap_cases_def.
ARM setCurrentPD was recently refactored as part of multi-VM support for
ARM_HYP. The Haskell was updated correctly, and the C was not.
Unfortunately, setCurrentPD was manually redefined in MachineOps.thy for
ARM hiding the change, making the C look correct when it wasn't.
We scrap the second definition of setCurrentPD, load it from the Haskell,
and have an abstract set_current_pd that's a bit simpler to refine down
from.
The proofs are updated for the above change and the update to the C
setCurrentPD that was breaking on KZM.
This patch adds a generic "post_cap_deletion" step that is called by
finalise_slot. Previous to this, the only caps which had actions
required at this stage were IRQHandlerCaps -- it was required that the
IRQ bitmap be updated after the cap itself was removed (as the
invariants state that for any existing IRQHandlerCap, the corresponding
bit in the IRQ bitmap must be set).
By genericising this, we add the capacity for new, arch-specific post
cap deletion actions to occur in the future.
message_info structs have 20 bit labels. On 32-bit systems, the label
does not need to be masked as there are no extra padding bits in the
struct, but this is not true for 64-bit systems. As a result, the
haskell needs to mask msgLabelBits (=20) when extracting the label in
messageInfoFromWord.
in addition to the a_type ATCB simplification, the following two are now in the simpset:
"a_type (Endpoint x) = AEndpoint"
"a_type (Notification v) = ANTFN"
This removes an ifdef present in invokeTCB_(Copy|Write)Registers, and
adds the function Arch_postModifyRegisters which does nothing on any
arch except x86-64.
Colloquially known as "invert-fastpath".
Update verification efforts on ARM for the following seL4 changes:
- scheduling decisions done in possibleSwitchTo are moved to the
scheduler
- possibleSwitchTo only checks whether the candidate is valid for a
fast switch, not its priority, accepting possible candidates
immmediately as a switch-to scheduler action
- the scheduler checks the candidate against the current thread and
against the bitmaps before making a decision
- attemptSwitchTo and switchIfRequiredTo are gone
- scheduler is now more complicated, and numerous proofs related to it
are rewritten from scratch
- fast path now checks ready queues via the scheduler bitmaps
- L2 scheduler bitmap order reversed for better cache locality
Many iterations between the kernel and verification teams were needed
to get this right.
This was broken a long while back because arch_switch_to_idle_thread
might sometimes be skipped in the implementation if the idle thread
was previously scheduled. Putting the same behaviour in the most
abstract (unit) specification is pretty easy, and it's not clear why
it wasn't done earlier.
This updates the proofs for a change in the C code. The IRQ control
syscall now returns an error whenever the IRQ parameter is not a valid
IRQ value. Previously, the syscall threw away some higher-order bits
before checking for IRQ validity.
Incidentally, the C now only uses the name `irq` for variables of type
`irq_t`, and `irq_w` for variables of type `word_t`. This avoids trouble
with c-parser name mangling.
Gerwin Klein
Victor Phan
Corey Lewis
MiladKetabi
Amirreza Zarrabi
Michael McInerney
Michael Sproul
Japheth Lim
Santiago Bautista
Edward Pierzchalski
Mitchell Buckley
Thomas Sewell
Matthew Brecknell
Rafal Kolanski
Joel Beeren
Miki Tanaka