In the past, the core-only privileged syscall `update_pd` was used only
to invalidate the TLB after removal of page-table entries.
By now, the whole TLB at least for one protection domain got invalidated,
but in preparation for optimization and upcomingARM v8 support,
it is necessary to deliver the virtual memory region that needs to get
invalidated. Moreover, the name of the call shall represent explicitely
that it is used to invalidate the TLB.
Ref #3405
Since gcc 8.3.0 generates SSE instructions into kernel code, the
kernel itself may raise FPU exceptions and/or corrupt user level FPU
contexts thereby. Both things are not feasible, and therefore, lazy FPU
switching becomes a no go for base-hw because we cannot avoid FPU
instructions because of the entanglement of base-hw, base, and the tool
chain (libgcc_eh.a).
issue #3365
Also disable TS (task switch) flag in cr0 during kernel initialization,
so FPU faults are not raised. This became necessary since GCC lately
aggressively generates FPU instructions at arbitrary places and also at
early kernel-bootstrapping stages.
fixes#3365
As far as possible remove usage of warning/error/log in the kernel,
otherwise the kernel context might try to take a lock hold by a core
thread, which results in a syscall to block.
Fix#3277
* Introduce 64-bit tick counter
* Let the timer always count when possible, also if it already fired
* Simplify the kernel syscall API to have one current time call,
which returns the elapsed microseconds since boot
- support to create multiple vCPUs
- support to implement Vm_session methods client side within base library
- adjust muen specific virtualbox4 version to compile/link
Issue #3111
This patch replaces the former prominent use of pointers by references
wherever feasible. This has the following benefits:
* The contract between caller and callee becomes more obvious. When
passing a reference, the contract says that the argument cannot be
a null pointer. The caller is responsible to ensure that. Therefore,
the use of reference eliminates the need to add defensive null-pointer
checks at the callee site, which sometimes merely exist to be on the
safe side. The bottom line is that the code becomes easier to follow.
* Reference members must be initialized via an object initializer,
which promotes a programming style that avoids intermediate object-
construction states. Within core, there are still a few pointers
as member variables left though. E.g., caused by the late association
of 'Platform_thread' objects with their 'Platform_pd' objects.
* If no pointers are present as member variables, we don't need to
manually provide declarations of a private copy constructor and
an assignment operator to avoid -Weffc++ errors "class ... has
pointer data members [-Werror=effc++]".
This patch also changes a few system bindings on NOVA and Fiasco.OC,
e.g., the return value of the global 'cap_map' accessor has become a
reference. Hence, the patch touches a few places outside of core.
Fixes#3135
This commit addresses several multiprocessing issues in base-hw:
* it reworks cross-cpu maintainance work for TLB invalidation by
introducing a generic Inter_processor_work and removes the so
called Cpu_domain_update
* thereby it solves the cross-cpu thread destruction, when the
corresponding thread is active on another cpu (fix#3043)
* it adds the missing TLB shootdown for x86 (fix#3042)
* on ARM it removes the TLB shootdown via IPIs, because this
is not needed on the multiprocessing ARM platforms we support
* it enables the per-cpu initialization of the kernel's cpu
objects, which means those object initialization is executed
by the proper cpu
* it rollbacks prior decision to make multiprocessing an aspect,
but puts back certain 'smp' mechanisms (like cross-cpu lock)
into the generic code base for simplicity reasons
The sinfo API now also exports PCI devices without logical IRQs.
Therefore, explicitly check interrupt count in get_msi_params() function
and ignore such devices.
The patch adjust the code of the base, base-<kernel>, and os repository.
To adapt existing components to fix violations of the best practices
suggested by "Effective C++" as reported by the -Weffc++ compiler
argument. The changes follow the patterns outlined below:
* A class with virtual functions can no longer publicly inherit base
classed without a vtable. The inherited object may either be moved
to a member variable, or inherited privately. The latter would be
used for classes that inherit 'List::Element' or 'Avl_node'. In order
to enable the 'List' and 'Avl_tree' to access the meta data, the
'List' must become a friend.
* Instead of adding a virtual destructor to abstract base classes,
we inherit the new 'Interface' class, which contains a virtual
destructor. This way, single-line abstract base classes can stay
as compact as they are now. The 'Interface' utility resides in
base/include/util/interface.h.
* With the new warnings enabled, all member variables must be explicitly
initialized. Basic types may be initialized with '='. All other types
are initialized with braces '{ ... }' or as class initializers. If
basic types and non-basic types appear in a row, it is nice to only
use the brace syntax (also for basic types) and align the braces.
* If a class contains pointers as members, it must now also provide a
copy constructor and assignment operator. In the most cases, one
would make them private, effectively disallowing the objects to be
copied. Unfortunately, this warning cannot be fixed be inheriting
our existing 'Noncopyable' class (the compiler fails to detect that
the inheriting class cannot be copied and still gives the error).
For now, we have to manually add declarations for both the copy
constructor and assignment operator as private class members. Those
declarations should be prepended with a comment like this:
/*
* Noncopyable
*/
Thread(Thread const &);
Thread &operator = (Thread const &);
In the future, we should revisit these places and try to replace
the pointers with references. In the presence of at least one
reference member, the compiler would no longer implicitly generate
a copy constructor. So we could remove the manual declaration.
Issue #465
Instead of changing the attributes (e.g., Xd bit) of the top-level page-tables,
set them to allow everything. Only leafs of the paging hierarchy are set
according to the paging attributes given by core. Otherwise, top-level page-
table attributes are changed during lifetime, which requires a TLB flush
operation (not intended in the semantic of the kernel/core).
This led to problems when using the non-executable features introduced by
issue #1723 in the recent past.
Recent work related to issue 1723 showed that there is potential
to get rid of code duplication in MMU fault handling especially
with regard to ARM cpus.
Emery Hemingway
Stefan Kalkowski
Sebastian Sumpf
Martin Stein
Christian Prochaska
Alexander Boettcher
Norman Feske
Christian Helmuth
Adrian-Ken Rueegsegger
Reto Buerki