3.13.11-ckt34 -stable review patch.  If anyone has any objections, please let 
me know.

---8<------------------------------------------------------------

From: Richard Cochran <[email protected]>

commit 1b9f23727abb92c5e58f139e7d180befcaa06fe0 upstream.

The posix_clock_poll function is supposed to return a bit mask of
POLLxxx values.  However, in case the hardware has disappeared (due to
hot plugging for example) this code returns -ENODEV in a futile
attempt to throw an error at the file descriptor level.  The kernel's
file_operations interface does not accept such error codes from the
poll method.  Instead, this function aught to return POLLERR.

The value -ENODEV does, in fact, contain the POLLERR bit (and almost
all the other POLLxxx bits as well), but only by chance.  This patch
fixes code to return a proper bit mask.

Credit goes to Markus Elfring for pointing out the suspicious
signed/unsigned mismatch.

Reported-by: Markus Elfring <[email protected]>
igned-off-by: Richard Cochran <[email protected]>
Cc: John Stultz <[email protected]>
Cc: Julia Lawall <[email protected]>
Link: 
http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Kamal Mostafa <[email protected]>
---
 kernel/time/posix-clock.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/time/posix-clock.c b/kernel/time/posix-clock.c
index ce033c7..9cff0ab 100644
--- a/kernel/time/posix-clock.c
+++ b/kernel/time/posix-clock.c
@@ -69,10 +69,10 @@ static ssize_t posix_clock_read(struct file *fp, char 
__user *buf,
 static unsigned int posix_clock_poll(struct file *fp, poll_table *wait)
 {
        struct posix_clock *clk = get_posix_clock(fp);
-       int result = 0;
+       unsigned int result = 0;
 
        if (!clk)
-               return -ENODEV;
+               return POLLERR;
 
        if (clk->ops.poll)
                result = clk->ops.poll(clk, fp, wait);
-- 
1.9.1

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