[PATCH] IB/hfi1: Fix logical condition in msix_request_irq

[PATCH] IB/hfi1: Fix logical condition in msix_request_irq

[Nathan Chancellor]

Clang warns:

drivers/infiniband/hw/hfi1/msix.c:136:22: warning: overlapping
comparisons always evaluate to false [-Wtautological-overlap-compare]
        if (type < IRQ_SDMA && type >= IRQ_OTHER)
            ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~
1 warning generated.

It is impossible for something to be less than 0 (IRQ_SDMA) and greater
than or equal to 3 (IRQ_OTHER) at the same time. A logical OR should
have been used to keep the same logic as before.

Link: https://github.com/ClangBuiltLinux/linux/issues/841
Fixes: 13d2a8384bd9 ("IB/hfi1: Decouple IRQ name from type")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
---
 drivers/infiniband/hw/hfi1/msix.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/infiniband/hw/hfi1/msix.c b/drivers/infiniband/hw/hfi1/msix.c
index 4a620cf80588..db82db497b2c 100644
--- a/drivers/infiniband/hw/hfi1/msix.c
+++ b/drivers/infiniband/hw/hfi1/msix.c
@@ -133,7 +133,7 @@ static int msix_request_irq(struct hfi1_devdata *dd, void *arg,
 	if (nr == dd->msix_info.max_requested)
 		return -ENOSPC;
 
-	if (type < IRQ_SDMA && type >= IRQ_OTHER)
+	if (type < IRQ_SDMA || type >= IRQ_OTHER)
 		return -EINVAL;
 
 	irq = pci_irq_vector(dd->pcidev, nr);
-- 
2.25.0

Re: [PATCH] IB/hfi1: Fix logical condition in msix_request_irq

[Nick Desaulniers]

On Thu, Jan 16, 2020 at 2:27 PM Nathan Chancellor
<natechancellor@gmail.com> wrote:
>
> Clang warns:
>
> drivers/infiniband/hw/hfi1/msix.c:136:22: warning: overlapping
> comparisons always evaluate to false [-Wtautological-overlap-compare]
>         if (type < IRQ_SDMA && type >= IRQ_OTHER)
>             ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~
> 1 warning generated.
>
> It is impossible for something to be less than 0 (IRQ_SDMA) and greater
> than or equal to 3 (IRQ_OTHER) at the same time. A logical OR should
> have been used to keep the same logic as before.
>
> Link: https://github.com/ClangBuiltLinux/linux/issues/841
> Fixes: 13d2a8384bd9 ("IB/hfi1: Decouple IRQ name from type")
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Thanks for the patch. LGTM.
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>

> ---
>  drivers/infiniband/hw/hfi1/msix.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/infiniband/hw/hfi1/msix.c b/drivers/infiniband/hw/hfi1/msix.c
> index 4a620cf80588..db82db497b2c 100644
> --- a/drivers/infiniband/hw/hfi1/msix.c
> +++ b/drivers/infiniband/hw/hfi1/msix.c
> @@ -133,7 +133,7 @@ static int msix_request_irq(struct hfi1_devdata *dd, void *arg,
>         if (nr == dd->msix_info.max_requested)
>                 return -ENOSPC;
>
> -       if (type < IRQ_SDMA && type >= IRQ_OTHER)
> +       if (type < IRQ_SDMA || type >= IRQ_OTHER)

-- 
Thanks,
~Nick Desaulniers

Re: [PATCH] IB/hfi1: Fix logical condition in msix_request_irq

[Dennis Dalessandro]

On 1/16/2020 5:26 PM, Nathan Chancellor wrote:
> Clang warns:
> 
> drivers/infiniband/hw/hfi1/msix.c:136:22: warning: overlapping
> comparisons always evaluate to false [-Wtautological-overlap-compare]
>          if (type < IRQ_SDMA && type >= IRQ_OTHER)
>              ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~
> 1 warning generated.
> 
> It is impossible for something to be less than 0 (IRQ_SDMA) and greater
> than or equal to 3 (IRQ_OTHER) at the same time. A logical OR should
> have been used to keep the same logic as before.
> 
> Link: https://github.com/ClangBuiltLinux/linux/issues/841
> Fixes: 13d2a8384bd9 ("IB/hfi1: Decouple IRQ name from type")
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com>

Re: [PATCH] IB/hfi1: Fix logical condition in msix_request_irq

[Jason]

On Thu, Jan 16, 2020 at 03:26:58PM -0700, Nathan Chancellor wrote:
> Clang warns:
> 
> drivers/infiniband/hw/hfi1/msix.c:136:22: warning: overlapping
> comparisons always evaluate to false [-Wtautological-overlap-compare]
>         if (type < IRQ_SDMA && type >= IRQ_OTHER)
>             ~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~
> 1 warning generated.
> 
> It is impossible for something to be less than 0 (IRQ_SDMA) and greater
> than or equal to 3 (IRQ_OTHER) at the same time. A logical OR should
> have been used to keep the same logic as before.
> 
> Link: https://github.com/ClangBuiltLinux/linux/issues/841
> Fixes: 13d2a8384bd9 ("IB/hfi1: Decouple IRQ name from type")
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
> Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
> ---
>  drivers/infiniband/hw/hfi1/msix.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Applied to for-next, thanks

Jason