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| author | Rosen Penev <rosenp@gmail.com> | 2026-09-27 13:35:01 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-10-01 11:04:53 +0200 |
| commit | 8167c1f071426706c233e93ecfd13aba7d5c06c8 (patch) | |
| tree | 2c0cd5f5e1cc35eadee98d49fe034f96a88856ce /lib/test_fpu_glue.c | |
| download | linux-stable-8167c1f071426706c233e93ecfd13aba7d5c06c8.tar.gz linux-stable-8167c1f071426706c233e93ecfd13aba7d5c06c8.zip | |
tty: serial: mpc52xx_uart: move static declarations up.grafted
Avoid a compilation error so that they're not used before being
declared.
Fixes: 4d105880666a ("tty: serial: mpc52xx_uart: add bounds check for psc_num array index")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202609260356.tJWbd1WU-lkp@intel.com/
Signed-off-by: Rosen Penev <rosenp@gmail.com>
Link: https://patch.msgid.link/20260927203501.14105-1-rosenp@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'lib/test_fpu_glue.c')
| -rw-r--r-- | lib/test_fpu_glue.c | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/lib/test_fpu_glue.c b/lib/test_fpu_glue.c new file mode 100644 index 000000000..c05964263 --- /dev/null +++ b/lib/test_fpu_glue.c @@ -0,0 +1,63 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Test cases for using floating point operations inside a kernel module. + * + * This tests kernel_fpu_begin() and kernel_fpu_end() functions, especially + * when userland has modified the floating point control registers. The kernel + * state might depend on the state set by the userland thread that was active + * before a syscall. + * + * To facilitate the test, this module registers file + * /sys/kernel/debug/selftest_helpers/test_fpu, which when read causes a + * sequence of floating point operations. If the operations fail, either the + * read returns error status or the kernel crashes. + * If the operations succeed, the read returns "1\n". + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/debugfs.h> +#include <linux/fpu.h> + +#include "test_fpu.h" + +static int test_fpu_get(void *data, u64 *val) +{ + int status = -EINVAL; + + kernel_fpu_begin(); + status = test_fpu(); + kernel_fpu_end(); + + *val = 1; + return status; +} + +DEFINE_DEBUGFS_ATTRIBUTE(test_fpu_fops, test_fpu_get, NULL, "%lld\n"); +static struct dentry *selftest_dir; + +static int __init test_fpu_init(void) +{ + if (!kernel_fpu_available()) + return -EINVAL; + + selftest_dir = debugfs_create_dir("selftest_helpers", NULL); + if (IS_ERR(selftest_dir)) + return -ENOMEM; + + debugfs_create_file_unsafe("test_fpu", 0444, selftest_dir, NULL, + &test_fpu_fops); + + return 0; +} + +static void __exit test_fpu_exit(void) +{ + debugfs_remove(selftest_dir); +} + +module_init(test_fpu_init); +module_exit(test_fpu_exit); + +MODULE_DESCRIPTION("Test cases for floating point operations"); +MODULE_LICENSE("GPL"); |
