[PATCH 4.9 25/95] powerpc/powernv: Handle unknown OPAL errors in opal_nvram_write()

[Greg Kroah-Hartman]

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

------------------

From: Nicholas Piggin <npig...@gmail.com>

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: sta...@vger.kernel.org # v3.2+
Signed-off-by: Nicholas Piggin <npig...@gmail.com>
Reviewed-by: Vasant Hegde <hegdevas...@linux.vnet.ibm.com>
Acked-by: Stewart Smith <stew...@linux.ibm.com>
Signed-off-by: Michael Ellerman <m...@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 arch/powerpc/platforms/powernv/opal-nvram.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/arch/powerpc/platforms/powernv/opal-nvram.c
+++ b/arch/powerpc/platforms/powernv/opal-nvram.c
@@ -59,6 +59,10 @@ static ssize_t opal_nvram_write(char *bu
                if (rc == OPAL_BUSY_EVENT)
                        opal_poll_events(NULL);
        }
+
+       if (rc)
+               return -EIO;
+
        *index += count;
        return count;
 }