The things that usually go wrong:
- wp fall through: add +, e.g.
apply (wp select_wp) -> apply (wp select_wp)+
- precondition: you can remove most hoare_pre, but wpc still needs it, and
sometimes the wp instance relies on being able to fit a rule to the
current non-schematic precondition. In that case, use "including no_pre"
to switch off the automatic hoare_pre application.
- very rarely there is a schematic postcondition that interferes with the
new trivial cleanup rules, because the rest of the script assumes some
specific state afterwards (shouldn't happen in a reasonable proof, but
not all proofs are reasonable..). In that case, (wp_once ...)+ should
emulate the old behaviour precisely.
New testfile for graph-refine export with new handling code. Also
some slight tweaks to some CRefine proofs that will be needed to
remove DONT_TRANSLATE markers from certain key places in the seL4
code. These proofs are also compatible with previous seL4.
* tcb_context rephrasing to (tcb_context o tcb_arch) and respectively
for set operations
* unfolding of reserved_irq for trivially solving most lemmas
* Changes to the inductive definition of integrity_obj to account for
tcb_arch and tcb_context new location
* Changes to the tcb examples in ExampleSystem to include tcb_arch
* Rephrasing of domain_sep_inv to accommodate the ReservedIRQ case
* Mostly rephrasing of tcb_context to (some form of) (tcb_context o tcb_arch)
* Trivial unfolding of handle_reserved_irq for hoare rules
* Examples in Example_Valid_State.thy were updated
* Nothing remarkable, mostly rephrasing of tcb_context and ReservedIRQ
handling
* Fun fact, some proofs are now shorter
tags: [VER-623][SELFOUR-413]
These changes to the automatons are required by:
SELFOUR-242: invert bitfield scheduler and optimise fast path
Details:
When we enter the kernel, the domain time left (ksDomainTime) is never zero.
If we entered on a timer interrupt, we may decrement it to zero before the
scheduler runs. If we do so, we set the scheduler state to choose_new_thread.
When choosing a new thread, the scheduler switches to a new domain if the
present one is required, and sets the new domain time left from domain_list
(ksDomSchedule).
When entering the kernel on a non-interrupt event, we never touch the domain
time left, which trivially preserves the new constraints.
To prove these, we had to ban a transition from kernel entry to kernel being
preempted when handling an interrupt event in InfoFlow. This is fine, as by
design handling interrupts is not meant to be preempted by interrupts.
UserOp_IF had its own way of extracting the XN bit from page tables.
This is now unified with the existing functions in ADT_AI, which also
means that the proof for XN bit equality is basically the same as for
pt_rights and pt_lift.
The fact that the C infoflow adt refines the abstract infoflow adt now only requires that given user operation is nonempty and not sane (nonempty and doesn't return an interrupt).
Also added some more general lemmas about fw_sim and refinement to lib/Simulation.thy.
Matthew Brecknell
Daniel Matichuk
Alejandro Gomez-Londono
Rafal Kolanski
Miki Tanaka
Gerwin Klein
Thomas Sewell
Xin,Gao
Japheth Lim
Matthew Brecknell
Joel Beeren
deang
David Greenaway