2016-05-26 09:35:00

by Maxime Coquelin

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Subject: [PATCH] hwrng: stm32: fix maybe uninitialized variable warning

This patch fixes the following warning:
drivers/char/hw_random/stm32-rng.c: In function 'stm32_rng_read':
drivers/char/hw_random/stm32-rng.c:82:19: warning: 'sr' may be used
uninitialized in this function

Reported-by: Sudip Mukherjee <[email protected]>
Suggested-by: Arnd Bergmann <[email protected]>
Cc: Daniel Thompson <[email protected]>
Signed-off-by: Maxime Coquelin <[email protected]>
---
drivers/char/hw_random/stm32-rng.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/char/hw_random/stm32-rng.c b/drivers/char/hw_random/stm32-rng.c
index 92a810648bd0..63d84e6f1891 100644
--- a/drivers/char/hw_random/stm32-rng.c
+++ b/drivers/char/hw_random/stm32-rng.c
@@ -69,8 +69,12 @@ static int stm32_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
}

/* If error detected or data not ready... */
- if (sr != RNG_SR_DRDY)
+ if (sr != RNG_SR_DRDY) {
+ if (WARN_ONCE(sr & (RNG_SR_SEIS | RNG_SR_CEIS),
+ "bad RNG status - %x\n", sr))
+ writel_relaxed(0, priv->base + RNG_SR);
break;
+ }

*(u32 *)data = readl_relaxed(priv->base + RNG_DR);

@@ -79,10 +83,6 @@ static int stm32_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
max -= sizeof(u32);
}

- if (WARN_ONCE(sr & (RNG_SR_SEIS | RNG_SR_CEIS),
- "bad RNG status - %x\n", sr))
- writel_relaxed(0, priv->base + RNG_SR);
-
pm_runtime_mark_last_busy((struct device *) priv->rng.priv);
pm_runtime_put_sync_autosuspend((struct device *) priv->rng.priv);

--
1.9.1


2016-05-27 13:47:01

by Daniel Thompson

[permalink] [raw]
Subject: Re: [PATCH] hwrng: stm32: fix maybe uninitialized variable warning

On 26/05/16 10:34, Maxime Coquelin wrote:
> This patch fixes the following warning:
> drivers/char/hw_random/stm32-rng.c: In function 'stm32_rng_read':
> drivers/char/hw_random/stm32-rng.c:82:19: warning: 'sr' may be used
> uninitialized in this function
>
> Reported-by: Sudip Mukherjee <[email protected]>
> Suggested-by: Arnd Bergmann <[email protected]>
> Cc: Daniel Thompson <[email protected]>

Reviewed-by: Daniel Thompson <[email protected]>


> Signed-off-by: Maxime Coquelin <[email protected]>
> ---
> drivers/char/hw_random/stm32-rng.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/char/hw_random/stm32-rng.c b/drivers/char/hw_random/stm32-rng.c
> index 92a810648bd0..63d84e6f1891 100644
> --- a/drivers/char/hw_random/stm32-rng.c
> +++ b/drivers/char/hw_random/stm32-rng.c
> @@ -69,8 +69,12 @@ static int stm32_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
> }
>
> /* If error detected or data not ready... */
> - if (sr != RNG_SR_DRDY)
> + if (sr != RNG_SR_DRDY) {
> + if (WARN_ONCE(sr & (RNG_SR_SEIS | RNG_SR_CEIS),
> + "bad RNG status - %x\n", sr))
> + writel_relaxed(0, priv->base + RNG_SR);
> break;
> + }
>
> *(u32 *)data = readl_relaxed(priv->base + RNG_DR);
>
> @@ -79,10 +83,6 @@ static int stm32_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
> max -= sizeof(u32);
> }
>
> - if (WARN_ONCE(sr & (RNG_SR_SEIS | RNG_SR_CEIS),
> - "bad RNG status - %x\n", sr))
> - writel_relaxed(0, priv->base + RNG_SR);
> -
> pm_runtime_mark_last_busy((struct device *) priv->rng.priv);
> pm_runtime_put_sync_autosuspend((struct device *) priv->rng.priv);
>
>

2016-05-31 10:18:14

by Herbert Xu

[permalink] [raw]
Subject: Re: [PATCH] hwrng: stm32: fix maybe uninitialized variable warning

On Thu, May 26, 2016 at 11:34:57AM +0200, Maxime Coquelin wrote:
> This patch fixes the following warning:
> drivers/char/hw_random/stm32-rng.c: In function 'stm32_rng_read':
> drivers/char/hw_random/stm32-rng.c:82:19: warning: 'sr' may be used
> uninitialized in this function
>
> Reported-by: Sudip Mukherjee <[email protected]>
> Suggested-by: Arnd Bergmann <[email protected]>
> Cc: Daniel Thompson <[email protected]>
> Signed-off-by: Maxime Coquelin <[email protected]>

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