Since 6.10-rc1, Qualcomm machines with a serial port can easily lock up hard, for example, when stopping a getty on reboot. The first patch in this series fixes this severe regression by restoring the pre-6.10-rc1 behaviour of printing additional characters when flushing the tx buffer. The second patch fixes a long-standing issue in the GENI driver which can lead to a soft lock up when using software flow control and on suspend. The third patch, addresses the old issue with additional characters being printing when flushing the buffer. Note that timeouts used when clearing the tx fifo are a bit excessive since I'm reusing the current qcom_geni_serial_poll_bit() helper for now. I think at least the first patch should be merged for rc6 while we consider the best way forward to address the remaining issues. Doug has posted an alternative series of fixes here that depends on reworking the driver a fair bit here: https://lore.kernel.org/lkml/20240610222515.3023730-1-dianders@xxxxxxxxxxxx/ Johan Johan Hovold (3): serial: qcom-geni: fix hard lockup on buffer flush serial: qcom-geni: fix soft lockup on sw flow control and suspend serial: qcom-geni: fix garbage output after buffer flush drivers/tty/serial/qcom_geni_serial.c | 36 +++++++++++++++++++-------- 1 file changed, 25 insertions(+), 11 deletions(-) -- 2.44.1
