The deadlock occured with three concurrently running threads: two
waiters calling pthread_cond_timedwait() and one signaller calling
pthread_cond_signal().
If waiter W1 hits its timeout, the signaller may have called
pthread_cond_signal(), detected this waiter and posted the internal
'signal_sem' concurrently. Then, the signaller waits for 'handshake_sem'
to ensure the waiter got woken up.
Waiter W1 can't consume the 'signal_sem' post by
'sem_wait(&c->signal_sem)' because another waiter W2 may have consumed
the post already above in sem_wait/timedwait(). Waiting for a post on
'signal_sem' would block the waiter W1 in perfect deadlock with
signaller on 'handshake_sem'. As W1 also owns 'counter_mutex' in this
situation, waiter W2 would block when trying to aquire 'counter_mutex'
and can't resolve the situation.
So, W1 does nothing in this case and we accept the spurious wakeup on
next pthread_cond_wait/timedwait().
* get rid of alarm abstraction
* get rid of Timeout::Time type
* get rid of pointer arguments
* get rid of _discard_timeout indirection
* get rid of 65th bit in stored time values
* get rid of Timeout_scheduler interface
* get rid of uninitialized deadlines
* get rid of default arguments
* get rid of Timeout::_periodic
* get rid of Timeout::Raw
* use list abstraction
* only one interface for timeout handlers
* rework locking scheme to be smp safe
* move all method definitions to CC file
* name mutexes more accurate
* fix when & how to set time-source timeout
* fix deadlocks
Fixes#3884
In case of contexts blocked in select() the monitor updates the
file-descriptor status, but if the entrypoint is just blocked for the
select handler, the status must be updated explicitly on
dispatch_select().
Like already done for terminal I/O controls use collect the information
by reading property files instead of using the old VFS ioctl interface.
Fixes#3888.
There is a type mismatch as in the FreeBSD contrib code the type of the
request is 'unsigned long'. So far, only I/O controls where the request
falls into the signed range where used and this was not a problem.
Some of the SNDCTL requests, however, have the bit set.
Fixes#3887.
This patch is a follow-up for the commit "libc: use monitor for fork".
It removes the use of the monitor mechanism from the
'Local_clone_service::close' RPC function because the fork_ep must stay
responsive for the destruction and creation of 'Child' objects.
Issue #3874
The combination of Net::Mac_address and
Genode::ascii_to(Net::Mac_address) required shaky quirks in several
places because GCC is not able to resolve the ascii_to overload if
base/xml_node.h was included to early. The current solution moves the
several ascii_to overloads "closer" to the Net types by putting them
into the Net namespace, where GCC reliably picks them up.
Hence, co-locating the ascii_to() utility with the overload type in the
same scope/namespace is good practice.
This patch removes the now obsolete <nic/xml_node.h> header file.
Introduce the managing_system privilege for components like the
platform_driver to allow it to call system management functionality
that is reserved by kernel or special firmware, e.g., ARM Trusted Firmware.
The former RAM resource configuration attribute `constrain_phys`,
which enabled to constrain the region of physical RAM to be used,
gets replaced by the new, broader managing_system configuration
attribute of a `start` node. It gets enforced by the sandbox library.
Ref #3816
Normally CLOCK_REALTIME is used. However libraries, like glib, want to
use CLOCK_MONOTONIC. To make those users happy add setting the clock.
Note, the pthread_cond implementation uses the POSIX semaphore API
internally that does not have means to set the clock. For this reason,
the private 'sem_set_clock' function is introduced.
Fixes#3846.
* add libsparkcrypto source-recipe
* provide ALI files through a new repository by mstein and add the repo
download to the libsparcrypto port-file
* remove dependencies to non-existent contrib ADB files from the library make
files
Fixes: #3852
This patch untangles the dependency of VFS operations that need RTC
information from the 'clock_gettime' libc function that must never be
called from the libc kernel context.
- The 'Rtc' class uses the VFS directly for reading the rtc file instead
of relying on libc functions.
- The 'Rtc' instance has become part of the 'Kernel' instead of
being construced as a side effect of the first call of
'clock_gettime'.
- Changed 'Rtc::read' to return a timespec value, which has a higher
precision than the formerly used time_t value.
- The 'Rtc::read' returns a value with the relative 'current_time'
already applied. The former handling of subsequent rtc-value
updates has been rewritten to become more logical.
- The 'Vfs_plugin' no longer calls 'clock_gettime' but the new
kernel-level 'Current_real_time' interface.
Issue #2635
This patch untangles the interplay of the base library and the libc
during the exit handling.
- The CXA ABI for the atexit handling is now provided by the libc.
For plain Genode components without libc dependency, __cxa_atexit
is a no-op, which is consistent with Genode's notion of components.
- The 'abort' implementation of the base library no longer calls
'genode_exit' but merely 'sleep_forever'. This way, the cxx library
no longer depends on a 'genode_exit' implementation.
- The libc provides 'atexit' support by storing metadata on the
libc kernel's heap now, thereby eliminating the former bounded
maximum number of atexit handlers.
- Shared-library dtors are no longer called via the atexit mechanism
by explicitly by the dynamic linker. This slightly changes the
call order of destructors (adjustment of the ldso test). Functions
marked as destructors are called after the atexit handlers now.
- The libc executes atexit handlers in the application context,
which supports the I/O operations in those handles, in particular
the closing of file descriptors.
Fixes#3851
For the time being, we put all spec and body files into the recipe although
there might be a (so far to us unknown) way to have only the API relevant files
in it.
Fixes#3849
* switch to a libsparkcrypto fork of m-stein
* switch to a libsparkcrypto state that makes some units pure that are used by
the consistent block encrypter, in order that the latter can become
completely pure
Ref #3849
* switch to fork of the Ada runtime provided by m-stein
* switch to a Ada-runtime state that provides the Exp_Int package (exponential
function on integers)
* adapt spark lib, symbols, and recipes to incorporate the Exp_Int package
Fixes#3848
* enable all common warnings through default value of CC_ADA_WARN
* treat warnings like errors through default value of CC_ADA_WARN_STRICT
* enable almost all style checks through default value of CC_ADA_WARN_STRICT
* style fixes for aes_cbc_4k
* disable strict warnings and style checks for libsparkcrypto and spark lib
Ref #3848
This patch prevents nitpicker from requesting a framebuffer and input
session by default because the regular use of nitpicker relies on the
capture-session and event-session interfaces by now.
For supporting the nested use of nitpicker via the gui_fb component, it
is still possible to enable the traditional behavior by explicitely
setting the 'request_input' and 'request_framebuffer' config attributes
to "yes".
Issue #3812
This remove the call to Io_progress_handler::handle_io_progress() from
wait_and_dispatch_one_io_signal() to prevent unexpected nesting
I/O-progress handling in case of custom dispatch loops (e.g., in libc).
The original intention of Io_progress_handler was to inform the
entrypoint just before blocking in the entrypoint loop.
Issue #2635
