From f95dabef4c70e27e5114f4802fe6234ff82ce406 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Wed, 25 Sep 2013 19:24:17 +1000 Subject: [PATCH] hwrng: Return errors to upper levels in pseries-rng.c 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 Signed-off-by: Benjamin Herrenschmidt --- 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 5f1197929f0c..b761459a3436 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 #include #include #include @@ -25,10 +28,15 @@ 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; }