u-boot/test/bootm.c
Sean Anderson ba9aa40bb3 bootm: Fix Linux silent console on newer kernels
Linux determines its console based on several sources:

1. the console command line parameter
2. device tree (e.g. /chosen/stdout-path)
3. various other board- and arch-specific sources

If the console parameter specifies a real console (e.g. ttyS0) then that is
used as /dev/console. However, if it does not specify a real console (e.g.
ttyDoesntExist) then *nothing* will be used as /dev/console.
Reading/writing it will return ENODEV. Additionally, no other source will
be used as a console source.

Linux commit ab4af56ae250 ("printk/console: Allow to disable console output
by using console="" or console=null") recently changed the semantics of the
parameter. Previously, specifying console="" would be treated like
specifying some other bad console. This commit changed things so that it
added /dev/ttynull as a console (if available).  However, it also allows
for other console sources. If the device tree specifies a console (such as
if U-Boot and Linux share a device tree), then it will be used in addition
to /dev/ttynull. This can result in a non-silent console.

To avoid this, explicitly set ttynull as the console. This will disable
other console sources. If CONFIG_NULL_TTY is disabled, then this will have
the same behavior as in the past (no output, and writing /dev/console
returns ENODEV).

[1] and [2] have additional background on this kernel change.

[1] https://lore.kernel.org/all/20201006025935.GA597@jagdpanzerIV.localdomain/
[2] https://lore.kernel.org/all/20201111135450.11214-1-pmladek@suse.com/

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
2022-06-06 18:01:21 -04:00

249 lines
7.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Tests for bootm routines
*
* Copyright 2020 Google LLC
*/
#include <common.h>
#include <bootm.h>
#include <asm/global_data.h>
#include <test/suites.h>
#include <test/test.h>
#include <test/ut.h>
DECLARE_GLOBAL_DATA_PTR;
#define BOOTM_TEST(_name, _flags) UNIT_TEST(_name, _flags, bootm_test)
enum {
BUF_SIZE = 1024,
};
#define CONSOLE_STR "console=/dev/ttyS0"
/* Test cmdline processing where nothing happens */
static int bootm_test_nop(struct unit_test_state *uts)
{
char buf[BUF_SIZE];
*buf = '\0';
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, true));
ut_asserteq_str("", buf);
strcpy(buf, "test");
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, true));
ut_asserteq_str("test", buf);
return 0;
}
BOOTM_TEST(bootm_test_nop, 0);
/* Test cmdline processing when out of space */
static int bootm_test_nospace(struct unit_test_state *uts)
{
char buf[BUF_SIZE];
/* Zero buffer size */
*buf = '\0';
ut_asserteq(-ENOSPC, bootm_process_cmdline(buf, 0, true));
/* Buffer string not terminated */
memset(buf, 'a', BUF_SIZE);
ut_asserteq(-ENOSPC, bootm_process_cmdline(buf, BUF_SIZE, true));
/* Not enough space to copy string */
memset(buf, '\0', BUF_SIZE);
memset(buf, 'a', BUF_SIZE / 2);
ut_asserteq(-ENOSPC, bootm_process_cmdline(buf, BUF_SIZE, true));
/* Just enough space */
memset(buf, '\0', BUF_SIZE);
memset(buf, 'a', BUF_SIZE / 2 - 1);
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, true));
return 0;
}
BOOTM_TEST(bootm_test_nospace, 0);
/* Test silent processing */
static int bootm_test_silent(struct unit_test_state *uts)
{
char buf[BUF_SIZE];
/* 'silent_linux' not set should do nothing */
env_set("silent_linux", NULL);
strcpy(buf, CONSOLE_STR);
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SILENT));
ut_asserteq_str(CONSOLE_STR, buf);
ut_assertok(env_set("silent_linux", "no"));
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SILENT));
ut_asserteq_str(CONSOLE_STR, buf);
ut_assertok(env_set("silent_linux", "yes"));
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SILENT));
ut_asserteq_str("console=ttynull", buf);
/* Empty buffer should still add the string */
*buf = '\0';
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SILENT));
ut_asserteq_str("console=ttynull", buf);
/* Check nothing happens when do_silent is false */
*buf = '\0';
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, 0));
ut_asserteq_str("", buf);
/* Not enough space */
*buf = '\0';
ut_asserteq(-ENOSPC, bootm_process_cmdline(buf, 15, BOOTM_CL_SILENT));
/* Just enough space */
*buf = '\0';
ut_assertok(bootm_process_cmdline(buf, 16, BOOTM_CL_SILENT));
/* add at end */
strcpy(buf, "something");
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SILENT));
ut_asserteq_str("something console=ttynull", buf);
/* change at start */
strcpy(buf, CONSOLE_STR " something");
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SILENT));
ut_asserteq_str("console=ttynull something", buf);
return 0;
}
BOOTM_TEST(bootm_test_silent, 0);
/* Test substitution processing */
static int bootm_test_subst(struct unit_test_state *uts)
{
char buf[BUF_SIZE];
/* try with an unset variable */
ut_assertok(env_set("var", NULL));
strcpy(buf, "some${var}thing");
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SUBST));
ut_asserteq_str("something", buf);
/* Replace with shorter string */
ut_assertok(env_set("var", "bb"));
strcpy(buf, "some${var}thing");
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SUBST));
ut_asserteq_str("somebbthing", buf);
/* Replace with same-length string */
ut_assertok(env_set("var", "abc"));
strcpy(buf, "some${var}thing");
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SUBST));
ut_asserteq_str("someabcthing", buf);
/* Replace with longer string */
ut_assertok(env_set("var", "abcde"));
strcpy(buf, "some${var}thing");
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SUBST));
ut_asserteq_str("someabcdething", buf);
/* Check it is case sensitive */
ut_assertok(env_set("VAR", NULL));
strcpy(buf, "some${VAR}thing");
ut_assertok(bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SUBST));
ut_asserteq_str("something", buf);
/* Check too long - need 12 bytes for each string */
strcpy(buf, "some${var}thing");
ut_asserteq(-ENOSPC,
bootm_process_cmdline(buf, 12 * 2 - 1, BOOTM_CL_SUBST));
/* Check just enough space */
strcpy(buf, "some${var}thing");
ut_assertok(bootm_process_cmdline(buf, 16 * 2, BOOTM_CL_SUBST));
ut_asserteq_str("someabcdething", buf);
/*
* Check the substition string being too long. This results in a string
* of 12 (13 bytes). We need enough space for that plus the original
* "a${var}c" string of 9 bytes. So 12 + 9 = 21 bytes.
*/
ut_assertok(env_set("var", "1234567890"));
strcpy(buf, "a${var}c");
ut_asserteq(-ENOSPC, bootm_process_cmdline(buf, 21, BOOTM_CL_SUBST));
strcpy(buf, "a${var}c");
ut_asserteq(0, bootm_process_cmdline(buf, 22, BOOTM_CL_SUBST));
/* Check multiple substitutions */
ut_assertok(env_set("var", "abc"));
strcpy(buf, "some${var}thing${bvar}else");
ut_asserteq(0, bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SUBST));
ut_asserteq_str("someabcthingelse", buf);
/* Check multiple substitutions */
ut_assertok(env_set("bvar", "123"));
strcpy(buf, "some${var}thing${bvar}else");
ut_asserteq(0, bootm_process_cmdline(buf, BUF_SIZE, BOOTM_CL_SUBST));
ut_asserteq_str("someabcthing123else", buf);
return 0;
}
BOOTM_TEST(bootm_test_subst, 0);
/* Test silent processing in the bootargs variable */
static int bootm_test_silent_var(struct unit_test_state *uts)
{
env_set("bootargs", NULL);
ut_assertok(bootm_process_cmdline_env(BOOTM_CL_SUBST));
ut_assertnull(env_get("bootargs"));
ut_assertok(env_set("bootargs", "some${var}thing"));
ut_assertok(bootm_process_cmdline_env(BOOTM_CL_SUBST));
ut_asserteq_str("something", env_get("bootargs"));
return 0;
}
BOOTM_TEST(bootm_test_silent_var, 0);
/* Test substitution processing in the bootargs variable */
static int bootm_test_subst_var(struct unit_test_state *uts)
{
env_set("bootargs", NULL);
ut_assertok(bootm_process_cmdline_env(BOOTM_CL_SILENT));
ut_asserteq_str("console=ttynull", env_get("bootargs"));
ut_assertok(env_set("var", "abc"));
ut_assertok(env_set("bootargs", "some${var}thing"));
ut_assertok(bootm_process_cmdline_env(BOOTM_CL_SILENT));
ut_asserteq_str("some${var}thing console=ttynull", env_get("bootargs"));
return 0;
}
BOOTM_TEST(bootm_test_subst_var, 0);
/* Test substitution and silent console processing in the bootargs variable */
static int bootm_test_subst_both(struct unit_test_state *uts)
{
ut_assertok(env_set("silent_linux", "yes"));
env_set("bootargs", NULL);
ut_assertok(bootm_process_cmdline_env(BOOTM_CL_ALL));
ut_asserteq_str("console=ttynull", env_get("bootargs"));
ut_assertok(env_set("bootargs", "some${var}thing " CONSOLE_STR));
ut_assertok(env_set("var", "1234567890"));
ut_assertok(bootm_process_cmdline_env(BOOTM_CL_ALL));
ut_asserteq_str("some1234567890thing console=ttynull", env_get("bootargs"));
return 0;
}
BOOTM_TEST(bootm_test_subst_both, 0);
int do_ut_bootm(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
{
struct unit_test *tests = UNIT_TEST_SUITE_START(bootm_test);
const int n_ents = UNIT_TEST_SUITE_COUNT(bootm_test);
return cmd_ut_category("bootm", "bootm_test_", tests, n_ents,
argc, argv);
}