[PATCH] mei: mei-amt-version: remove unneeded call of mei_deinit()

From: Paul Bolle
Date: Fri Jan 03 2014 - 12:10:40 EST


On Fri, 2014-01-03 at 16:34 +0000, David Howells wrote:
> Paul Bolle <pebolle@xxxxxxxxxx> wrote:
> > But it turns out that call of mei_deinit() isn't needed at all. All of
> > the members of mei_cl will be set later in mei_init() and none will be
> > used before they are set. So we can simply drop this call of
> > mei_deinit()."
> >
> > Is that analysis (still) correct?
>
> It looks true as the code stands. Can you send me your patch?

Sure. Below the scissors (hope I've typed those correctly).


Paul Bolle
-------->8-------
From: Paul Bolle <pebolle@xxxxxxxxxx>

Building mei-amt-version.o triggers a GCC warning:
Documentation/misc-devices/mei/mei-amt-version.c: In function 'main':
Documentation/misc-devices/mei/mei-amt-version.c:103:5: warning: 'acmd.fd' is used uninitialized in this function [-Wuninitialized]
if (cl->fd != -1)
^
Documentation/misc-devices/mei/mei-amt-version.c:443:21: note: 'acmd.fd' was declared here
struct amt_host_if acmd;
^

GCC is correct. See, the call chain that GCC detects must be
main()
amt_host_if_init()
mei_init()
mei_deinit()

But when we enter mei_deinit() struct amt_host_if acmd is still
unitialized. That makes the test for (effectively) amt_host_if->mei_cl->fd
bogus.

But it turns out that call of mei_deinit() isn't needed at all. All of
the members of mei_cl will be set later in mei_init() and none will be
used before they are set. So we can simply drop this call of
mei_deinit().

Signed-off-by: Paul Bolle <pebolle@xxxxxxxxxx>
---
Documentation/misc-devices/mei/mei-amt-version.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/Documentation/misc-devices/mei/mei-amt-version.c b/Documentation/misc-devices/mei/mei-amt-version.c
index 49e4f77..57d0d87 100644
--- a/Documentation/misc-devices/mei/mei-amt-version.c
+++ b/Documentation/misc-devices/mei/mei-amt-version.c
@@ -115,8 +115,6 @@ static bool mei_init(struct mei *me, const uuid_le *guid,
struct mei_client *cl;
struct mei_connect_client_data data;

- mei_deinit(me);
-
me->verbose = verbose;

me->fd = open("/dev/mei", O_RDWR);
--
1.8.4.2

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