chardev: force write all when recording replay logs

This is mostly a problem within avocado as serial generally isn't busy
enough to overfill pipes. However the consequences of recording a
failed write will haunt us on replay when the log will be out of sync
to the playback.

Fixes: https://gitlab.com/qemu-project/qemu/-/issues/2010
Acked-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20231211091346.14616-13-alex.bennee@linaro.org>
This commit is contained in:
Alex Bennée 2023-12-11 09:13:41 +00:00
parent 1f881ea4a4
commit 7b571ef3c7

View file

@ -171,6 +171,18 @@ int qemu_chr_write(Chardev *s, const uint8_t *buf, int len, bool write_all)
return res;
}
if (replay_mode == REPLAY_MODE_RECORD) {
/*
* When recording we don't want temporary conditions to
* perturb the result. By ensuring we write everything we can
* while recording we avoid playback being out of sync if it
* doesn't encounter the same temporary conditions (usually
* triggered by external programs not reading the chardev fast
* enough and pipes filling up).
*/
write_all = true;
}
res = qemu_chr_write_buffer(s, buf, len, &offset, write_all);
if (qemu_chr_replay(s) && replay_mode == REPLAY_MODE_RECORD) {