6.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Doug Brown <doug@xxxxxxxxxxxxx> commit c5603e2a621dac10c5e21cc430848ebcfa6c7e01 upstream. This reverts commit 7bfb915a597a301abb892f620fe5c283a9fdbd77. This commit broke pxa and omap-serial, because it inhibited them from calling stop_tx() if their TX FIFOs weren't completely empty. This resulted in these two drivers hanging during transmits because the TX interrupt would stay enabled, and a new TX interrupt would never fire. Cc: stable@xxxxxxxxxxxxxxx Fixes: 7bfb915a597a ("serial: core: only stop transmit when HW fifo is empty") Signed-off-by: Doug Brown <doug@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20240606195632.173255-2-doug@xxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/linux/serial_core.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -789,8 +789,7 @@ enum UART_TX_FLAGS { if (pending < WAKEUP_CHARS) { \ uart_write_wakeup(__port); \ \ - if (!((flags) & UART_TX_NOSTOP) && pending == 0 && \ - __port->ops->tx_empty(__port)) \ + if (!((flags) & UART_TX_NOSTOP) && pending == 0) \ __port->ops->stop_tx(__port); \ } \ \