mirror of
https://github.com/freebsd/freebsd-src.git
synced 2024-12-04 08:09:08 +00:00
e012fe34cb
When multiple threads wish to report a tracing event to a debugger, both threads call ptracestop() and one thread will win the race to be the reporting thread (p->p_xthread). The debugger uses PT_LWPINFO with the process ID to determine which thread / LWP is reporting an event and the details of that event. This event is cleared as a side effect of the subsequent ptrace event that resumed the process (PT_CONTINUE, PT_STEP, etc.). However, ptrace() was clearing the event identified by the LWP ID passed to the resume request even if that wasn't the 'p_xthread'. This could result in clearing an event that had not yet been observed by the debugger and leaving the existing event for 'p_thread' pending so that it was reported a second time. Specifically, if the debugger stopped due to a software breakpoint in one thread, but then switched to another thread that was used to resume (e.g. if the user switched to a different thread and issued a step), the resume request (PT_STEP) cleared a pending event (if any) for the thread being stepped. However, the process immediately stopped and the first thread reported it's breakpoint event a second time. The debugger decremented the PC for "both" breakpoint events which resulted in the PC now pointing into the middle of an instruction (on x86) and a SIGILL fault when the process was resumed a second time. To fix, always clear the pending event for 'p_xthread' when resuming a process. ptrace() still honors the requested LWP ID when enabling single-stepping (PT_STEP) or setting a different PC (PT_CONTINUE). Reported by: GDB testsuite (gdb.threads/continue-pending-status.exp) Reviewed by: kib MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D12794 |
||
|---|---|---|
| .. | ||
| etc | ||
| freebsd_test_suite | ||
| sys | ||
| Kyuafile | ||
| Makefile | ||
| Makefile.depend | ||
| Makefile.inc0 | ||
| README | ||
src/tests: The FreeBSD test suite
=================================
To run the FreeBSD test suite:
(1) Make sure that kyua is installed:
pkg install kyua
(2) To run the tests:
kyua test -k /usr/tests/Kyuafile
(3) To see the test results:
kyua report
For further information on using the test suite, read tests(7):
man tests
Description of FreeBSD test suite
=================================
The build of the test suite is organized in the following manner:
* The build of all test artifacts is protected by the MK_TESTS knob.
The user can disable these with the WITHOUT_TESTS setting in
src.conf(5).
* The goal for /usr/tests/ (the installed test programs) is to follow
the same hierarchy as /usr/src/ wherever possible, which in turn drives
several of the design decisions described below. This simplifies the
discoverability of tests. We want a mapping such as:
/usr/src/bin/cp/ -> /usr/tests/bin/cp/
/usr/src/lib/libc/ -> /usr/tests/lib/libc/
/usr/src/usr.bin/cut/ -> /usr/tests/usr.bin/cut/
... and many more ...
* Test programs for specific utilities and libraries are located next
to the source code of such programs. For example, the tests for the
src/lib/libcrypt/ library live in src/lib/libcrypt/tests/. The tests/
subdirectory is optional and should, in general, be avoided.
* The src/tests/ hierarchy (this directory) provides generic test
infrastructure and glue code to join all test programs together into
a single test suite definition.
* The src/tests/ hierarchy also includes cross-functional test programs:
i.e. test programs that cover more than a single utility or library
and thus don't fit anywhere else in the tree. Consider this to follow
the same rationale as src/share/man/: this directory contains generic
manual pages while the manual pages that are specific to individual
tools or libraries live next to the source code.
In order to keep the src/tests/ hierarchy decoupled from the actual test
programs being installed --which is a worthy goal because it simplifies
the addition of new test programs and simplifies the maintenance of the
tree-- the top-level Kyuafile does not know which subdirectories may
exist upfront. Instead, such Kyuafile automatically detects, at
run-time, which */Kyuafile files exist and uses those directly.
Similarly, every directory in src/ that wants to install a Kyuafile to
just recurse into other subdirectories reuses this Kyuafile with
auto-discovery features. As an example, take a look at src/lib/tests/
whose sole purpose is to install a Kyuafile into /usr/tests/lib/.
The goal in this specific case is for /usr/tests/lib/ to be generated
entirely from src/lib/.
--
$FreeBSD$