2022-08-22 11:26:57

by Kshitiz Varshney

Subject: [PATCH v1] Moving IRQ handler registering after imx_rngc_irq_mask_clear()

Issue:
While servicing interrupt, if the IRQ happens to be because of a SEED_DONE
due to a previous boot stage, you end up completing the completion
prematurely, hence causing kernel to crash while booting.

Fix:
Moving IRQ handler registering after imx_rngc_irq_mask_clear()

Fixes: 1d5449445bd0 (hwrng: mx-rngc - add a driver for Freescale RNGC)
Signed-off-by: Kshitiz Varshney <[email protected]>
---
drivers/char/hw_random/imx-rngc.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
index 53e571c4f283..0b71ed850809 100644
--- a/drivers/char/hw_random/imx-rngc.c
+++ b/drivers/char/hw_random/imx-rngc.c
@@ -272,14 +272,6 @@ static int imx_rngc_probe(struct platform_device *pdev)

init_completion(&rngc->rng_op_done);

- ret = devm_request_irq(&pdev->dev,
- irq, imx_rngc_irq, 0, pdev->name, (void *)rngc);
- if (ret) {
- dev_err(rngc->dev, "Can't get interrupt working.\n");
- goto err;
- }
-
-
rngc->rng.name = pdev->name;
rngc->rng.init = imx_rngc_init;
rngc->rng.read = imx_rngc_read;
@@ -291,6 +283,14 @@ static int imx_rngc_probe(struct platform_device *pdev)

imx_rngc_irq_mask_clear(rngc);

+
+ ret = devm_request_irq(&pdev->dev,
+ irq, imx_rngc_irq, 0, pdev->name, (void *)rngc);
+
+ if (ret) {
+ dev_err(rngc->dev, "Can't get interrupt working.\n");
+ goto err;
+ }
if (self_test) {
ret = imx_rngc_self_test(rngc);
if (ret) {
--
2.25.1

2022-09-02 11:01:48

by Herbert Xu

Subject: Re: [PATCH v1] Moving IRQ handler registering after imx_rngc_irq_mask_clear()

On Mon, Aug 22, 2022 at 01:19:03PM +0200, Kshitiz Varshney wrote:
> Issue:
> While servicing interrupt, if the IRQ happens to be because of a SEED_DONE
> due to a previous boot stage, you end up completing the completion
> prematurely, hence causing kernel to crash while booting.
>
> Fix:
> Moving IRQ handler registering after imx_rngc_irq_mask_clear()
>
> Fixes: 1d5449445bd0 (hwrng: mx-rngc - add a driver for Freescale RNGC)
> Signed-off-by: Kshitiz Varshney <[email protected]>
> ---
> drivers/char/hw_random/imx-rngc.c | 16 ++++++++--------
> 1 file changed, 8 insertions(+), 8 deletions(-)

Patch applied. Thanks.
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt