* [PATCH] ARM: OMAP: Fix use of possibly uninitialized irq variable
@ 2021-04-01 16:11 Maciej Falkowski
2021-04-01 16:45 ` Nathan Chancellor
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Maciej Falkowski @ 2021-04-01 16:11 UTC (permalink / raw)
To: khilman, aaro.koskinen, tony, linux
Cc: linux-omap, linux-arm-kernel, linux-kernel, clang-built-linux,
maciej.falkowski9
The current control flow of IRQ number assignment to `irq` variable
allows a request of IRQ of unspecified value,
generating a warning under Clang compilation with omap1_defconfig on linux-next:
arch/arm/mach-omap1/pm.c:656:11: warning: variable 'irq' is used uninitialized whenever
'if' condition is false [-Wsometimes-uninitialized]
else if (cpu_is_omap16xx())
^~~~~~~~~~~~~~~~~
./arch/arm/mach-omap1/include/mach/soc.h:123:30: note: expanded from macro 'cpu_is_omap16xx'
^~~~~~~~~~~~~
arch/arm/mach-omap1/pm.c:658:18: note: uninitialized use occurs here
if (request_irq(irq, omap_wakeup_interrupt, 0, "peripheral wakeup",
^~~
arch/arm/mach-omap1/pm.c:656:7: note: remove the 'if' if its condition is always true
else if (cpu_is_omap16xx())
^~~~~~~~~~~~~~~~~~~~~~
arch/arm/mach-omap1/pm.c:611:9: note: initialize the variable 'irq' to silence this warning
int irq;
^
= 0
1 warning generated.
The patch provides a default value to the `irq` variable
along with a validity check.
Signed-off-by: Maciej Falkowski <maciej.falkowski9@gmail.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/1324
---
arch/arm/mach-omap1/pm.c | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/arch/arm/mach-omap1/pm.c b/arch/arm/mach-omap1/pm.c
index 2c1e2b32b9b3..a745d64d4699 100644
--- a/arch/arm/mach-omap1/pm.c
+++ b/arch/arm/mach-omap1/pm.c
@@ -655,9 +655,13 @@ static int __init omap_pm_init(void)
irq = INT_7XX_WAKE_UP_REQ;
else if (cpu_is_omap16xx())
irq = INT_1610_WAKE_UP_REQ;
- if (request_irq(irq, omap_wakeup_interrupt, 0, "peripheral wakeup",
- NULL))
- pr_err("Failed to request irq %d (peripheral wakeup)\n", irq);
+ else
+ irq = -1;
+
+ if (irq >= 0) {
+ if (request_irq(irq, omap_wakeup_interrupt, 0, "peripheral wakeup", NULL))
+ pr_err("Failed to request irq %d (peripheral wakeup)\n", irq);
+ }
/* Program new power ramp-up time
* (0 for most boards since we don't lower voltage when in deep sleep)
--
2.26.3
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH] ARM: OMAP: Fix use of possibly uninitialized irq variable
2021-04-01 16:11 [PATCH] ARM: OMAP: Fix use of possibly uninitialized irq variable Maciej Falkowski
@ 2021-04-01 16:45 ` Nathan Chancellor
2021-04-01 19:05 ` Nick Desaulniers
2021-05-18 6:32 ` Tony Lindgren
2 siblings, 0 replies; 4+ messages in thread
From: Nathan Chancellor @ 2021-04-01 16:45 UTC (permalink / raw)
To: Maciej Falkowski
Cc: khilman, aaro.koskinen, tony, linux, linux-omap,
linux-arm-kernel, linux-kernel, clang-built-linux
On Thu, Apr 01, 2021 at 06:11:27PM +0200, Maciej Falkowski wrote:
> The current control flow of IRQ number assignment to `irq` variable
> allows a request of IRQ of unspecified value,
> generating a warning under Clang compilation with omap1_defconfig on linux-next:
>
> arch/arm/mach-omap1/pm.c:656:11: warning: variable 'irq' is used uninitialized whenever
> 'if' condition is false [-Wsometimes-uninitialized]
> else if (cpu_is_omap16xx())
> ^~~~~~~~~~~~~~~~~
> ./arch/arm/mach-omap1/include/mach/soc.h:123:30: note: expanded from macro 'cpu_is_omap16xx'
> ^~~~~~~~~~~~~
> arch/arm/mach-omap1/pm.c:658:18: note: uninitialized use occurs here
> if (request_irq(irq, omap_wakeup_interrupt, 0, "peripheral wakeup",
> ^~~
> arch/arm/mach-omap1/pm.c:656:7: note: remove the 'if' if its condition is always true
> else if (cpu_is_omap16xx())
> ^~~~~~~~~~~~~~~~~~~~~~
> arch/arm/mach-omap1/pm.c:611:9: note: initialize the variable 'irq' to silence this warning
> int irq;
> ^
> = 0
> 1 warning generated.
>
> The patch provides a default value to the `irq` variable
> along with a validity check.
>
Might be worth a fixes tag:
Fixes: b75ca5217743 ("ARM: OMAP: replace setup_irq() by request_irq()")
> Signed-off-by: Maciej Falkowski <maciej.falkowski9@gmail.com>
> Link: https://github.com/ClangBuiltLinux/linux/issues/1324
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
> ---
> arch/arm/mach-omap1/pm.c | 10 +++++++---
> 1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm/mach-omap1/pm.c b/arch/arm/mach-omap1/pm.c
> index 2c1e2b32b9b3..a745d64d4699 100644
> --- a/arch/arm/mach-omap1/pm.c
> +++ b/arch/arm/mach-omap1/pm.c
> @@ -655,9 +655,13 @@ static int __init omap_pm_init(void)
> irq = INT_7XX_WAKE_UP_REQ;
> else if (cpu_is_omap16xx())
> irq = INT_1610_WAKE_UP_REQ;
> - if (request_irq(irq, omap_wakeup_interrupt, 0, "peripheral wakeup",
> - NULL))
> - pr_err("Failed to request irq %d (peripheral wakeup)\n", irq);
> + else
> + irq = -1;
> +
> + if (irq >= 0) {
> + if (request_irq(irq, omap_wakeup_interrupt, 0, "peripheral wakeup", NULL))
> + pr_err("Failed to request irq %d (peripheral wakeup)\n", irq);
> + }
>
> /* Program new power ramp-up time
> * (0 for most boards since we don't lower voltage when in deep sleep)
> --
> 2.26.3
>
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] ARM: OMAP: Fix use of possibly uninitialized irq variable
2021-04-01 16:11 [PATCH] ARM: OMAP: Fix use of possibly uninitialized irq variable Maciej Falkowski
2021-04-01 16:45 ` Nathan Chancellor
@ 2021-04-01 19:05 ` Nick Desaulniers
2021-05-18 6:32 ` Tony Lindgren
2 siblings, 0 replies; 4+ messages in thread
From: Nick Desaulniers @ 2021-04-01 19:05 UTC (permalink / raw)
To: Maciej Falkowski
Cc: khilman, aaro.koskinen, tony, Russell King, linux-omap,
Linux ARM, LKML, clang-built-linux
On Thu, Apr 1, 2021 at 9:12 AM Maciej Falkowski
<maciej.falkowski9@gmail.com> wrote:
>
> The current control flow of IRQ number assignment to `irq` variable
> allows a request of IRQ of unspecified value,
> generating a warning under Clang compilation with omap1_defconfig on linux-next:
>
> arch/arm/mach-omap1/pm.c:656:11: warning: variable 'irq' is used uninitialized whenever
> 'if' condition is false [-Wsometimes-uninitialized]
> else if (cpu_is_omap16xx())
> ^~~~~~~~~~~~~~~~~
> ./arch/arm/mach-omap1/include/mach/soc.h:123:30: note: expanded from macro 'cpu_is_omap16xx'
> ^~~~~~~~~~~~~
> arch/arm/mach-omap1/pm.c:658:18: note: uninitialized use occurs here
> if (request_irq(irq, omap_wakeup_interrupt, 0, "peripheral wakeup",
> ^~~
> arch/arm/mach-omap1/pm.c:656:7: note: remove the 'if' if its condition is always true
> else if (cpu_is_omap16xx())
> ^~~~~~~~~~~~~~~~~~~~~~
> arch/arm/mach-omap1/pm.c:611:9: note: initialize the variable 'irq' to silence this warning
> int irq;
> ^
> = 0
> 1 warning generated.
Ooh, yeah if cpu_is_omap15xx() then irq is unused uninitialized; I
don't see any INT_1610_WAKE_UP_REQ-equlivalent for
INT_15XX_WAKE_UP_REQ.
Ok, LGTM.
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
I agree with Nathan on the Fixes tag.
>
> The patch provides a default value to the `irq` variable
> along with a validity check.
>
> Signed-off-by: Maciej Falkowski <maciej.falkowski9@gmail.com>
> Link: https://github.com/ClangBuiltLinux/linux/issues/1324
> ---
> arch/arm/mach-omap1/pm.c | 10 +++++++---
> 1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm/mach-omap1/pm.c b/arch/arm/mach-omap1/pm.c
> index 2c1e2b32b9b3..a745d64d4699 100644
> --- a/arch/arm/mach-omap1/pm.c
> +++ b/arch/arm/mach-omap1/pm.c
> @@ -655,9 +655,13 @@ static int __init omap_pm_init(void)
> irq = INT_7XX_WAKE_UP_REQ;
> else if (cpu_is_omap16xx())
> irq = INT_1610_WAKE_UP_REQ;
> - if (request_irq(irq, omap_wakeup_interrupt, 0, "peripheral wakeup",
> - NULL))
> - pr_err("Failed to request irq %d (peripheral wakeup)\n", irq);
> + else
> + irq = -1;
> +
> + if (irq >= 0) {
> + if (request_irq(irq, omap_wakeup_interrupt, 0, "peripheral wakeup", NULL))
> + pr_err("Failed to request irq %d (peripheral wakeup)\n", irq);
> + }
>
> /* Program new power ramp-up time
> * (0 for most boards since we don't lower voltage when in deep sleep)
> --
--
Thanks,
~Nick Desaulniers
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] ARM: OMAP: Fix use of possibly uninitialized irq variable
2021-04-01 16:11 [PATCH] ARM: OMAP: Fix use of possibly uninitialized irq variable Maciej Falkowski
2021-04-01 16:45 ` Nathan Chancellor
2021-04-01 19:05 ` Nick Desaulniers
@ 2021-05-18 6:32 ` Tony Lindgren
2 siblings, 0 replies; 4+ messages in thread
From: Tony Lindgren @ 2021-05-18 6:32 UTC (permalink / raw)
To: Maciej Falkowski
Cc: khilman, aaro.koskinen, linux, linux-omap, linux-arm-kernel,
linux-kernel, clang-built-linux
* Maciej Falkowski <maciej.falkowski9@gmail.com> [210401 19:13]:
> The current control flow of IRQ number assignment to `irq` variable
> allows a request of IRQ of unspecified value,
> generating a warning under Clang compilation with omap1_defconfig on linux-next:
>
> arch/arm/mach-omap1/pm.c:656:11: warning: variable 'irq' is used uninitialized whenever
> 'if' condition is false [-Wsometimes-uninitialized]
> else if (cpu_is_omap16xx())
> ^~~~~~~~~~~~~~~~~
> ./arch/arm/mach-omap1/include/mach/soc.h:123:30: note: expanded from macro 'cpu_is_omap16xx'
> ^~~~~~~~~~~~~
> arch/arm/mach-omap1/pm.c:658:18: note: uninitialized use occurs here
> if (request_irq(irq, omap_wakeup_interrupt, 0, "peripheral wakeup",
> ^~~
> arch/arm/mach-omap1/pm.c:656:7: note: remove the 'if' if its condition is always true
> else if (cpu_is_omap16xx())
> ^~~~~~~~~~~~~~~~~~~~~~
> arch/arm/mach-omap1/pm.c:611:9: note: initialize the variable 'irq' to silence this warning
> int irq;
> ^
> = 0
Thanks applying into fixes.
Tony
^ permalink raw reply [flat|nested] 4+ messages in thread
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2021-04-01 16:45 ` Nathan Chancellor
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