2020-01-16 23:26:55

by Nathan Chancellor

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

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 <[email protected]>
---
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

2020-01-16 23:28:11

by Nick Desaulniers

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

On Thu, Jan 16, 2020 at 2:27 PM Nathan Chancellor
<[email protected]> 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 <[email protected]>

Thanks for the patch. LGTM.
Reviewed-by: Nick Desaulniers <[email protected]>

> ---
> 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

2020-01-17 17:15:56

by Dennis Dalessandro

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

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 <[email protected]>

Acked-by: Dennis Dalessandro <[email protected]>

2020-01-25 19:38:02

by Jason Gunthorpe

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

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 <[email protected]>
> Reviewed-by: Nick Desaulniers <[email protected]>
> Acked-by: Dennis Dalessandro <[email protected]>
> ---
> drivers/infiniband/hw/hfi1/msix.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)

Applied to for-next, thanks

Jason