The frame-pointer-based backtrace does not work without enabling
-fno-omit-frame-pointer explicitly and in most cases leads to page
faults because non-pointer stack values are dereferenced during the
walk. The best we can do is to limit the backtrace walk to the stack of
the current thread to prevent page faults unrelated to the system state
without the use of the backtrace utility.
This commit introduces a printable Backtrace class usable in
Genode::log(), Genode::trace(), etc. The class is based on the new
function for_each_return_address(auto const &fn) that walks the stack in
its limits and calls fn() for each discovered return address on the
stack in the new os/include/os/backtrace.h. Archtecture-specific
stack-pointer retrieval and walk loops are implemented in dedicated
os/include/spec/<arch>/os/for_each_return_address.h files. Also, the
well-known Genode::backtrace() function (which logs the return-address
values) is provided for backwards compatibility.
Fixes#5078
The number of hash entries for TCP/UDP corresponds to the number of
sockets managed by the stack. In case there are more sockets than
entries available, buckets will be created to compensate for the lack of
space. The default values for TCP (524288) and UDP (65536) are meant for
the in kernel that manages all sockets of the user land and leads
to very large hash table allocations (>20MB) during initialization.
Since on Genode a component has its own instance of the IP stack or uses
the VFS server, we do not need these kind of large default settings.
issue #2181
This patch changes the unlink operation of the ram fs to defer the
destruction of a file until it is no longer referenced by any VFS handle.
When unlinked, the file no longer appears in the directory. But it can
still be opened and accessed.
With this change, a parent process of a Unix-like subsystem becomes able
to pass the content of an unlinked file to a forked child process. This
mechanism is required when using the 'exec' command in Tcl scripts.
Another use case is the 'tmpfile()' function.
Fixes#3577
The traced top instance was configured to be active every two seconds
whereas the trace test uses a grace time of only 1.5 seconds before
raising the FOREIGN state of a trace subject as an error.
The state of a trace subject can change only whenever the traced thread
passes a trace point. Hence, with the original configuration, the
release of top as trace subject can take up to two seconds. The patch
reduces the rate to 0.5 seconds to satisfy the expectation of
test-trace.
Following Github support removal for svn [1], dde_rump port fails to
prepare. This commit introduces a new install rule for ports,
'.sparse-git'. It performs a sparse-checkout on the port repository, only
fetching required files.
[1] https://github.blog/2023-01-20-sunsetting-subversion-support/
Co-authored-by: Benjamin Lamowski <benjamin.lamowski@genode-labs.com>
Issue genodelabs#5072
Issue genodelabs/goa#28
According to RFC 1812 ICMP Destination unreachable (Network unreachable)
does not quite our case of clients directly behind the router.
If a packet is to be forwarded to a host on a network that is directly
connected to the router (i.e., the router is the last-hop router) and
the router has ascertained that there is no path to the destination
host then the router MUST generate a Destination Unreachable, Code 1
(Host Unreachable) ICMP message.
Issue #4729
By using `mktime()`, which assumes local time, we render the `TZ`
environment variable ineffective. Instead, `timegm()` should be used to
set the real-time clock to UTC.
genodelabs/genode#5074
The management of Linux page structs is now tied to the life time of DMA
buffers. Thus, page structs are created when a buffer is allocated and
deallocated only when a buffer is freed - not on lx_emul_mem_free()
because DMA buffers are cached. Page struct refcounting was entirely
reworked in lx_emul/shadow/mm/page_alloc.c.
Fixes#4809
When multiple threads (EMT-0..X + nic_ep) enter the very same
critical section, the use of RTCritSectTryEnter may reflect the contention
case to the Network Model (E1000). Since no one notifies the model, when the
critical section is free again, solely the next packet/event triggered by the
guest will resume the former operation. This may lead to long delays until
packets are sent actually.
Instead of using the RTCritSectTryEnter use RTCritSecEnter to avoid the
situation. All of our network code is non blocking, so the network backend
will only be contented a short time.
Follow up commit to
Issue #5045
The devio API in the Linux kernel promised to be a stable layer for our
USB host controller drivers, but the additional bookkeeping and dynamic
allocations increase CPU overhead in a way that we do not accept further.
Therefore, we go a step back and process DMA transactions directly in and
out of the packet stream from the clients.
Fixgenodelabs/genode#5071
Per default Tslab checks that 8 slabs incl. overhead fit into one block.
If this is not desired the template parameter 'MIN_SLABS_PER_BLOCK' can
be used to control the minimum number of blocks.
Fixes#3834
The argument was originally designated to restrict the reach of the
trace monitor but the idea remained unimplemented. It is now superseded
by the use of the trace-session label as trace-subject filter.
Issue #847
This patch changes core's TRACE service to expose trace subjects only if
their PD label matches the label of the TRACE monitor. Hence, by default,
a trace monitor can only observe itself and its child components. Only
if the trace monitor's parent rewrites the trace-session's label, the
view of trace monitor can become broader. For example, when rewriting
the trace label to an empty string "", the trace monitor becomes able to
observe the sibling components hosted in the same init instance as the
trace monitor.
To grant a trace session the special privilege of obtaining a global
system view (including the kernel's trace subjects), the top-level init
has to rewrite the session's label to an empty string. At core, this
specific label "init -> " is handled as a special case that discharges
the filtering/namespacing of trace subjects.
Note that the trace-subject label as reported as subject info is now
given relative to the label of the trace session. As a nice side effect
of this change, the pkg/test-trace_logger works now when executed by the
depot_autopilot as well as via the test.run script.
Issue #847
This option is useful in cases where batching is configured and
failing to fetch a resource should not influence the over-all
result.
Issue genodelabs/genodians.org#32.
