[PATCH V2] kdb: match return value to function signature

From: Nicholas Mc Guire
Date: Tue May 12 2015 - 10:58:37 EST


kdb_task_state_string() introduced in the initial commit 5d5314d6795f
("kdb: core for kgdb back end (1 of 2)") returns unsigned long (a bit
array of states) but intermediately it is being assigned to a long which
make static code checkers unhappy and also does not help readability
(technically there is no reason to use a signed type here).

Type-checking coccinelle spatches are being used to locate type mismatches
between function signatures and return values in this case it produced:
./kernel/debug/kdb/kdb_support.c:611 WARNING: return of wrong type
unsigned long != long

Patch was compile tested with x86_64_defconfig + CONFIG_KGDB=y,
CONFIG_KGDB_KDB=y

Patch is against 4.1-rc3 (localversion-next is -next-20150512)

Signed-off-by: Nicholas Mc Guire <hofrat@xxxxxxxxx>
---

V2: As suggested by Daniel Thompson <daniel.thompson@xxxxxxxxxx> rather
than reformatting the entire comment just drop the type information

All (5) call-sites of kdb_task_state_string() were checked and all are
expecting an unsigned long as the function signature provides - so this
change should have no effect as automatic type conversion did not make
the signed type visible externally and internally the signed nature was
not in use.

Doc fixup: just remove the type information here.

kernel/debug/kdb/kdb_support.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/debug/kdb/kdb_support.c b/kernel/debug/kdb/kdb_support.c
index d35cc2d..80a2a098 100644
--- a/kernel/debug/kdb/kdb_support.c
+++ b/kernel/debug/kdb/kdb_support.c
@@ -544,7 +544,7 @@ int kdb_putword(unsigned long addr, unsigned long word, size_t size)
* Returns:
* Mask for process state.
* Notes:
- * The mask folds data from several sources into a single long value, so
+ * The mask folds data from several sources into a single value, so
* be careful not to overlap the bits. TASK_* bits are in the LSB,
* special cases like UNRUNNABLE are in the MSB. As of 2.6.10-rc1 there
* is no overlap between TASK_* and EXIT_* but that may not always be
@@ -560,7 +560,7 @@ int kdb_putword(unsigned long addr, unsigned long word, size_t size)

unsigned long kdb_task_state_string(const char *s)
{
- long res = 0;
+ unsigned long res = 0;
if (!s) {
s = kdbgetenv("PS");
if (!s)
--
1.7.10.4

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