Re: [PATCH v4 3/3] lib/test_crc: Add test cases for crc calculation

[Andrew Morton]

On Thu, 19 Jul 2018 00:55:45 +0800 Coly Li <colyli@xxxxxxx> wrote:

> This patch adds a kernel module to test the consistency of multiple crc
> calculation in Linux kernel. It is enabled with CONFIG_TEST_CRC enabled.
> 
> The test results are printed into kernel message, which look like,
> 
> test_crc: crc64_be: FAILED (0x03d4d0d85685d9a1, expected 0x3d4d0d85685d9a1f)
> 
> kernel 0day system has framework to check kernel message, then the above
> result can be handled by 0day system. If crc calculation inconsistency
> happens, it can be detected quite soon.
> 
> lib/test_crc.c is a testing frame work for many crc consistency
> testings. For now, there is only one test caes for crc64_be().

Some tweaks.



From: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Subject: lib-test_crc-add-test-cases-for-crc-calculation-fix

make two globals static, regularize code layout, remove unneeded initialization

Cc: Coly Li <colyli@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 lib/test_crc.c |   11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff -puN lib/test_crc.c~lib-test_crc-add-test-cases-for-crc-calculation-fix lib/test_crc.c
--- a/lib/test_crc.c~lib-test_crc-add-test-cases-for-crc-calculation-fix
+++ a/lib/test_crc.c
@@ -25,8 +25,8 @@ struct crc_test_record {
 	void	(*handler)(struct crc_test_record *rec);
 };
 
-int failed_tests;
-int total_tests;
+static int failed_tests;
+static int total_tests;
 
 static void chk_and_msg(const char *name, u64 crc, u64 expval)
 {
@@ -68,9 +68,6 @@ static int __init test_crc_init(void)
 {
 	int i;
 
-	failed_tests = 0;
-	total_tests = 0;
-
 	pr_info("Kernel CRC consistency testing:\n");
 	for (i = 0; test_data[i].name; i++)
 		test_data[i].handler(&test_data[i]);
@@ -85,7 +82,9 @@ static int __init test_crc_init(void)
 }
 late_initcall(test_crc_init);
 
-static void __exit test_crc_exit(void) { }
+static void __exit test_crc_exit(void)
+{
+}
 module_exit(test_crc_exit);
 
 MODULE_DESCRIPTION("CRC consistency testing driver");
_