lkml.org 
[lkml]   [2013]   [Sep]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/2] hwrng: Return errors to upper levels in pseries-rng.c
Date
We don't expect to get errors from the hypervisor when reading the rng,
but if we do we should pass the error up to the hwrng driver. Otherwise
the hwrng driver will continue calling us forever.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
---
drivers/char/hw_random/pseries-rng.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/char/hw_random/pseries-rng.c b/drivers/char/hw_random/pseries-rng.c
index 9dbeed3..ab7ffde 100644
--- a/drivers/char/hw_random/pseries-rng.c
+++ b/drivers/char/hw_random/pseries-rng.c
@@ -17,6 +17,9 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/

+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/hw_random.h>
#include <asm/vio.h>
@@ -24,10 +27,15 @@

static int pseries_rng_data_read(struct hwrng *rng, u32 *data)
{
- if (plpar_hcall(H_RANDOM, (unsigned long *)data) != H_SUCCESS) {
- printk(KERN_ERR "pseries rng hcall error\n");
- return 0;
+ int rc;
+
+ rc = plpar_hcall(H_RANDOM, (unsigned long *)data);
+ if (rc != H_SUCCESS) {
+ pr_err_ratelimited("H_RANDOM call failed %d\n", rc);
+ return -EIO;
}
+
+ /* The hypervisor interface returns 64 bits */
return 8;
}

--
1.8.1.2


\
 
 \ /
  Last update: 2013-09-25 11:41    [W:0.796 / U:0.412 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site