diff --git a/meta-oe/recipes-test/linux-serial-test/files/0002-linux-serial-test.c-fix-potential-hang-in-while-loop.patch b/meta-oe/recipes-test/linux-serial-test/files/0002-linux-serial-test.c-fix-potential-hang-in-while-loop.patch new file mode 100644 index 0000000000..f0b7f65a60 --- /dev/null +++ b/meta-oe/recipes-test/linux-serial-test/files/0002-linux-serial-test.c-fix-potential-hang-in-while-loop.patch @@ -0,0 +1,60 @@ +From 9cf6c1d80c2f159dbb69967fbe934bf6de73c9e8 Mon Sep 17 00:00:00 2001 +From: Max Krummenacher +Date: Tue, 5 Aug 2025 09:35:06 +0200 +Subject: [PATCH 2/2] linux-serial-test.c: fix potential hang in while loop + +process_read_data() assumes that we can always wait for reception +of 1024 chars. However that is not true if one sets the number of +chars with the '-w' cmdline parameter or chars are lost. Maybe there +are other reasons. + +Replace the magic number of 1024 by calculating the number of expected +chars from _cl_tx_bytes. + +Brake a possible infinite while loop by adding a timeout to the loop +calculated from the expected chars times chartime. + +Upstream-Status: Submitted [https://github.com/cbrake/linux-serial-test/pull/61/] +Fixes: 7fd1057f8a95 ("Add loop to read all data in rcv buffer") +Signed-off-by: Max Krummenacher +Signed-off-by: Emanuele Ghidoli +--- + linux-serial-test.c | 14 ++++++++++++-- + 1 file changed, 12 insertions(+), 2 deletions(-) + +diff --git a/linux-serial-test.c b/linux-serial-test.c +index c2c8882d601b..294f53882570 100644 +--- a/linux-serial-test.c ++++ b/linux-serial-test.c +@@ -543,8 +543,13 @@ static unsigned char next_count_value(unsigned char c) + static void process_read_data(void) + { + unsigned char rb[1024]; ++ int loopcounter = 0; + int actual_read_count = 0; +- while (actual_read_count < 1024) { ++ int expected_read_count = _cl_tx_bytes == 0 ? 1024 : _cl_tx_bytes; ++ /* time for one char at current baudrate in us */ ++ int chartime = 1000000 * (8 + _cl_parity + 1 + _cl_2_stop_bit) / _cl_baud; ++ ++ while (actual_read_count < expected_read_count) { + int c = read(_fd, &rb, sizeof(rb)); + if (c > 0) { + if (_cl_rx_dump) { +@@ -577,7 +582,12 @@ static void process_read_data(void) + if (errno != EAGAIN) { + perror("read failed"); + } +- continue; // Retry the read ++ ++ if (loopcounter++ < expected_read_count) { ++ usleep(chartime); ++ continue; // Retry the read ++ } ++ break; + } else { + break; + } +-- +2.43.0 + diff --git a/meta-oe/recipes-test/linux-serial-test/linux-serial-test_git.bb b/meta-oe/recipes-test/linux-serial-test/linux-serial-test_git.bb index 66511bd9c3..7a206319e7 100644 --- a/meta-oe/recipes-test/linux-serial-test/linux-serial-test_git.bb +++ b/meta-oe/recipes-test/linux-serial-test/linux-serial-test_git.bb @@ -5,6 +5,7 @@ LIC_FILES_CHKSUM = "file://LICENSES/MIT;md5=544799d0b492f119fa04641d1b8868ed" SRC_URI = "git://github.com/cbrake/linux-serial-test.git;protocol=https;branch=master \ file://0001-linux-serial-test.c-fix-returned-error-code.patch \ + file://0002-linux-serial-test.c-fix-potential-hang-in-while-loop.patch \ " PV = "0+git" SRCREV = "1a81f3c7be086ee01a9be8589a606426276c86d5"