On Thu, Apr 1, 2021 at 9:12 AM Maciej Falkowski <maciej.falkowski9@xxxxxxxxx> 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@xxxxxxxxxx> 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@xxxxxxxxx> > 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
