powerpc/powernv: Handle unknown OPAL errors in opal_nvram_write()

commit 741de617661794246f84a21a02fc5e327bffc9ad upstream.

opal_nvram_write currently just assumes success if it encounters an
error other than OPAL_BUSY or OPAL_BUSY_EVENT. Have it return -EIO
on other errors instead.

Fixes: 628daa8d5abf ("powerpc/powernv: Add RTC and NVRAM support plus RTAS fallbacks")
Cc: stable@vger.kernel.org # v3.2+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Acked-by: Stewart Smith <stewart@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/powerpc/platforms/powernv/opal-nvram.c b/arch/powerpc/platforms/powernv/opal-nvram.c
index f9896fd5d04afa1acc62f6ca6e82e25edce65d85..4d68026e0e7c4ffd6351540d4aab78c29fbf8f2b 100644 (file)
--- a/arch/powerpc/platforms/powernv/opal-nvram.c
+++ b/arch/powerpc/platforms/powernv/opal-nvram.c
@@ -58,6 +58,10 @@ static ssize_t opal_nvram_write(char *buf, size_t count, loff_t *index)
                if (rc == OPAL_BUSY_EVENT)
                        opal_poll_events(NULL);
        }
+
+       if (rc)
+               return -EIO;
+
        *index += count;
        return count;
 }