This patch replaces the exception-based error propagation by the use of
'Attempt' return values, which eliminates side effects of the exception
handling - cxx_heap allocations - from code paths that are used by the
the cxx_heap itself (when growing the cxx_heap).
It thereby fixes the failure of the sub_rm test at the "attach RAM ds to
any position at sub rm - this should fail" step.
Fixes#4953
This patch replaces the internal use 'env_deprecated()' from the
implementation of the thread API in the base library. It also
replaces the global accessor 'main_thread_cap' by the explicit
propagation of the main-thread's capability to the single point of
use via a new 'init_thread_bootstap' function.
Issue #4784
The new 'init_platform' function performs the platform-specific
component-local low-level initialization. It allows for the
differentiation between core and regular components as well as
kernel-dependent peculiarities.
This patch introduces a consistent notion of a 'Platform'. Within core,
the 'Platform' contains the kernel-specific initialization. Outside
core, the platform sets up the interplay with the parent component. In
all cases, the platform is constructed while running on the initial
stack.
Issue #4784
Tracing must be inhibited in attach/detach as RPC trace points may
trigger attachment of trace dataspaces, which would result in nested
mutex acquisition.
This prevents errors in test-trace_logger like follows.
[init -> depot_autopilot] 0.140 [init -> dynamic_rom] Error: deadlock ahead, mutex=0x500e6f00, return ip=0x50053ed7
Fixes#4607
Introduce two new cache maintainance functions:
* cache_clean_invalidate_data
* cache_invalidate_data
used to flush or invalidate data-cache lines.
Both functions are typically empty, accept for the ARM architecture.
The commit provides implementations for the base-hw kernel, and Fiasco.OC.
Fixes#4207
This patch simplifies the use of the clone system call for creating
processes and threads. Until now, the binding used an opaque pointer
argument to pass context information to the newly created process or
thread. However, upon close inspection, this is not a strict
requirement.
A newly created thread accesses its contextual information by
using its stack pointer as key. The pointer argument is not used.
The creation of processes is strictly serialized because the
intermediate stack used in-between clone and execve is a global
variable. Since we rely on the serialization anyway, we can pass the
context information of a new process via a global variable as well.
This change simplifies the syscall binding for the upcoming AARCH64
support, which would otherwise require us to deal with the notion
of TLS on Linux.
Issue #4136
base-linux uses seccomp to reduce the available system calls
to the minimum set needed to run base-linux. There are still
some syscalls that allow accessing global state which should
be further reduced.
The combination of seccomp and socket descriptor caps should
provide an intermediate level of security for base-linux
thereby enabling base-linux as a migration path from using
the Linux kernel to the use of microkernel-based Genode.
Fixes#3581
This patch largely reverts the commit "base: lay groundwork for
base-linux caps change" because the use of 'epoll' instead of 'select'
alleviated the need to allocate large FD sets, which motivated the
introduction of the 'Native_context' hook.
Related to issue #3581
On Linux, Genode used to represent each RPC object by a socket
descriptor of the receiving thread (entrypoint) and a globally-unique
value that identifies the object. Because the latter was transferred as
plain message payload, clients had to be trusted to not forge the
values. For this reason, Linux could not be considered as a productive
Genode base platform but remained merely a development vehicle.
This patch changes the RPC mechanism such that each RPC object is
represented by a dedicated socket pair. Entrypoints wait on a set of
the local ends of the socket pairs of all RPC objects managed by the
respective entrypoint. The epoll kernel interface is used as the
underlying mechanism to wait for a set of socket descriptors at the
server side.
When delegating a capability, the remote end of the socket pair is
transferred to the recipient along with a plaintext copy of the
socket-descriptor value of the local end. The latter value serves as a
hint for re-identifiying a capability whenever it is delegated back to
its origin. Note that the client is not trusted to preserve this
information. The integrity of the hint value is protected by comparing
the inode values of incoming and already present capablities at the
originating site (whenever the capability is invoked or presented to the
owner of the RPC object).
The new mechanism effectively equips base-linux with Genode's capablity
model as described in the Chapter 3 of the Genode Foundations book.
That said, the sandboxing of components cannot be assumed at this point
because each component has still direct access to the Linux system-call
interface.
This patch is based on the extensive exploration work conducted by
Stefan Thoeni who strongly motivated the inclusion of this feature into
Genode.
Issue #3581
This restores behavior introduced in
commit cb232891bf
Author: Norman Feske <norman.feske@genode-labs.com>
Date: Tue May 10 11:55:25 2016 +0200
Fix noux.run on base-linux
but removed by issue #2829.
Related to issue #1938
This commit removes APIs that were previously marked as deprecated. This
change has the following implications:
- The use of the global 'env()' accessor is not possible anymore.
- Boolean accessor methods are no longer prefixed with 'is_'. E.g.,
instead of 'is_valid()', use 'valid()'.
- The last traces of 'Ram_session' are gone now. The 'Env::ram()'
accessor returns the 'Ram_allocator' interface, which is a subset of
the 'Pd_session' interface.
- All connection constructors need the 'Env' as argument.
- The 'Reporter' constructor needs an 'Env' argument now because the
reporter creates a report connection.
- The old overload 'Child_policy::resolve_session_request' that returned
a 'Service' does not exist anymore.
- The base/printf.h header has been removed, use base/log.h instead.
- The old notion of 'Signal_dispatcher' is gone. Use 'Signal_handler'.
- Transitional headers like os/server.h, cap_session/,
volatile_object.h, os/attached*_dataspace.h, signal_rpc_dispatcher.h
have been removed.
- The distinction between 'Thread_state' and 'Thread_state_base' does
not exist anymore.
- The header cpu_thread/capability.h along with the type definition of
'Cpu_thread_capability' has been removed. Use the type
'Thread_capability' define in cpu_session/cpu_session.h instead.
- Several XML utilities (i.e., at os/include/decorator) could be removed
because their functionality is nowadays covered by util/xml_node.h.
- The 'os/ram_session_guard.h' has been removed.
Use 'Constrained_ram_allocator' provided by base/ram_allocator.h instead.
Issue #1987
This patch adjusts the implementation of the base library and core such
that the code no longer relies on deprecated APIs except for very few
cases, mainly to keep those deprecated APIs in tact for now.
The most prominent changes are:
- Removing the use of base/printf.h
- Removing of the log backend for printf. The 'Console' with the
format-string parser is still there along with 'snprintf.h' because
the latter is still used at a few places, most prominently the
'Connection' classes.
- Removing the notion of a RAM session, which does not exist in
Genode anymore. Still the types were preserved (by typedefs to
PD session) to keep up compatibility. But this transition should
come to an end now.
- Slight rennovation of core's tracing service, e.g., the use of an
Attached_dataspace as the Argument_buffer.
- Reducing the reliance on global accessors like deprecated_env() or
core_env(). Still there is a longish way to go to eliminate all such
calls. A useful pattern (or at least a stop-gap solution) is to
pass the 'Env' to the individual compilation units via init functions.
- Avoiding the use of the old 'Child_policy::resolve_session_request'
interface that returned a 'Service' instead of a 'Route'.
Issue #1987
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 patch removes the detection of statically linked executables from
the base framework. It thereby fixes the corner cases encountered with
Sculpt when obtaining the binaries of the runtime from the depot_rom
service that is hosted within the runtime.
Statically linked binaries and hybrid Linux/Genode (lx_hybrid) binaries
can still be started by relabeling the ROM-session route of "ld.lib.so"
to the binary name, pretending that the binary is the dynamic linker.
This can be achieved via init's label rewriting mechanism:
<route>
<service name="ROM" unscoped_label="ld.lib.so">
<parent label="test-platform"/> </service>
</route>
However, as this is quite cryptic and would need to be applied for all
lx_hybrid components, the patch adds a shortcut to init's configuration.
One can simply add the 'ld="no"' attribute to the <start> node of the
corresponding component:
<start name="test-platform" ld="no"/>
Fixes#2866
The native CPU client holds a capability reference and the reference
counter of the capability can reach its limit when many threads are
successively created and destroyed (destroyed by the Linux kernel).
Fixes#2886
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
The 'Stack_area_ram_session' is now a 'Stack_area_ram_allocator', which
simplifies the code and remove a dependency from the 'Ram_session'
interface, which we want to remove after all.
Issue #2407
This patch reduces the number of exception types by facilitating
globally defined exceptions for common usage patterns shared by most
services. In particular, RPC functions that demand a session-resource
upgrade not longer reflect this condition via a session-specific
exception but via the 'Out_of_ram' or 'Out_of_caps' types.
Furthermore, the 'Parent::Service_denied', 'Parent::Unavailable',
'Root::Invalid_args', 'Root::Unavailable', 'Service::Invalid_args',
'Service::Unavailable', and 'Local_service::Factory::Denied' types have
been replaced by the single 'Service_denied' exception type defined in
'session/session.h'.
This consolidation eases the error handling (there are fewer exceptions
to handle), alleviates the need to convert exceptions along the
session-creation call chain, and avoids possible aliasing problems
(catching the wrong type with the same name but living in a different
scope).
This patch enables warnings if one of the deprecate functions that rely
in the implicit use of the global Genode::env() accessor are called.
For the time being, some places within the base framework continue
to rely on the global function while omitting the warning by calling
'env_deprecated' instead of 'env'.
Issue #1987