3.16.57-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Horia Geantă <horia.geanta@xxxxxxx>
commit 225ece3e7dad4cfc44cca38ce7a3a80f255ea8f1 upstream.
In case DECO0 cannot be acquired - i.e. run_descriptor_deco0() fails
with -ENODEV, caam_probe() enters an endless loop:
run_descriptor_deco0
ret -ENODEV
-> instantiate_rng
-ENODEV, overwritten by -EAGAIN
ret -EAGAIN
-> caam_probe
-EAGAIN results in endless loop
It turns out the error path in instantiate_rng() is incorrect,
the checks are done in the wrong order.
Fixes: 1005bccd7a4a6 ("crypto: caam - enable instantiation of all RNG4 state handles")
Reported-by: Bryan O'Donoghue <pure.logic@xxxxxxxxxxxxxxxxx>
Suggested-by: Auer Lukas <lukas.auer@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Horia Geantă <horia.geanta@xxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/crypto/caam/ctrl.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
--- a/drivers/crypto/caam/ctrl.c
+++ b/drivers/crypto/caam/ctrl.c
@@ -196,12 +196,16 @@ static int instantiate_rng(struct device
* without any error (HW optimizations for later
* CAAM eras), then try again.
*/
+ if (ret)
+ break;
+
rdsta_val =
rd_reg32(&topregs->ctrl.r4tst[0].rdsta) & RDSTA_IFMASK;
- if (status || !(rdsta_val & (1 << sh_idx)))
+ if (status || !(rdsta_val & (1 << sh_idx))) {
ret = -EAGAIN;
- if (ret)
break;
+ }
+
dev_info(ctrldev, "Instantiated RNG4 SH%d\n", sh_idx);
/* Clear the contents before recreating the descriptor */
