Like replay_linux.py, reverse_debugging.py starts the vm with console
set but does not interact with it (e.g., with wait_for_console_pattern).
In this situation, the console should have a drainer attached so the
socket does not fill. replay_linux.py has a drainer, but it is missing
from reverse_debugging.py.
Per analysis in Link: this can cause the console socket/pipe to fill and
QEMU get stuck in qemu_chr_write_buffer, leading to strange test case
failures (ppc64 fails because it prints a lot to console in early bios).
Attaching a drainer prevents this.
Note, this commit does not fix bugs introduced by the commits referenced
in the first two Fixes: tags, but together those commits conspire to
irritate the problem and cause test case failure, which this commit
fixes.
Link: https://lore.kernel.org/qemu-devel/ZVT-bY9YOr69QTPX@redhat.com/
Fixes: 1d4796cd00 ("python/machine: use socketpair() for console connections")
Fixes: 761a13b239 ("tests/avocado: ppc64 reverse debugging tests for pseries and powernv")
Fixes: be52eca309 ("tests/acceptance: add reverse debugging test")
Tested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-ID: <20231116115354.228678-1-npiggin@gmail.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
These machines run reverse-debugging well enough to pass basic tests.
Wire them up.
Reviewed-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
The reverse-debugging test creates a trace, then replays it and:
1. Steps the first 10 instructions and records their addresses.
2. Steps backward and verifies their addresses match.
3. Runs to (near) the end of the trace.
4. Sets breakpoints on the first 10 instructions.
5. Continues backward and verifies execution stops at the last
breakpoint.
Step 5 breaks if any of the other 9 breakpoints are re-executed in the
trace after the 10th instruction is run, because those will be
unexpectedly hit when reverse continuing. This situation does arise
with the ppc pseries machine, the SLOF bios branches to its own entry
point.
Deal with this by switching steps 3 and 4, so the trace will be run to
the end *or* one of the breakpoints being re-executed. Step 5 then
reverses from there to the 10th instruction will not hit a breakpoint in
between, by definition.
Another step is added between steps 2 and 3, which steps forward over
the first 10 instructions and verifies their addresses, to support this.
Reviewed-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
This allows the test to be skipped when TCG is not present in the QEMU
binary.
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
In the discussion about renaming the `tests/acceptance` [1], the
conclusion was that the folders inside `tests` are related to the
framework running the tests and not directly related to the type of
the tests.
This changes the folder to `tests/avocado` and adjusts the MAKEFILE, the
CI related files and the documentation.
[1] https://lists.gnu.org/archive/html/qemu-devel/2021-05/msg06553.html
Reviewed-by: Niek Linnenbank <nieklinnenbank@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Willian Rampazzo <willianr@redhat.com>
Message-Id: <20211105155354.154864-3-willianr@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2021-11-08 17:00:22 +01:00
Renamed from tests/acceptance/reverse_debugging.py (Browse further)
