2023-04-07 07:27:00

by Denis Plotnikov

[permalink] [raw]
Subject: [PATCH net-next v2] qlcnic: check pci_reset_function result

Static code analyzer complains to unchecked return value.
The result of pci_reset_function() is unchecked.
Despite, the issue is on the FLR supported code path and in that
case reset can be done with pcie_flr(), the patch uses less invasive
approach by adding the result check of pci_reset_function().

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 7e2cf4feba05 ("qlcnic: change driver hardware interface mechanism")
Signed-off-by: Denis Plotnikov <[email protected]>
---
drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c
index 87f76bac2e463..eb827b86ecae8 100644
--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c
@@ -628,7 +628,13 @@ int qlcnic_fw_create_ctx(struct qlcnic_adapter *dev)
int i, err, ring;

if (dev->flags & QLCNIC_NEED_FLR) {
- pci_reset_function(dev->pdev);
+ err = pci_reset_function(dev->pdev);
+ if (err) {
+ dev_err(&dev->pdev->dev,
+ "Adapter reset failed (%d). Please reboot\n",
+ err);
+ return err;
+ }
dev->flags &= ~QLCNIC_NEED_FLR;
}

--
2.25.1


2023-04-07 09:07:32

by Simon Horman

[permalink] [raw]
Subject: Re: [PATCH net-next v2] qlcnic: check pci_reset_function result

On Fri, Apr 07, 2023 at 10:18:49AM +0300, Denis Plotnikov wrote:
> Static code analyzer complains to unchecked return value.
> The result of pci_reset_function() is unchecked.
> Despite, the issue is on the FLR supported code path and in that
> case reset can be done with pcie_flr(), the patch uses less invasive
> approach by adding the result check of pci_reset_function().
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> Fixes: 7e2cf4feba05 ("qlcnic: change driver hardware interface mechanism")
> Signed-off-by: Denis Plotnikov <[email protected]>

Thanks Denis,

With reference to,

Link: https://lore.kernel.org/all/20230405193708.GA3632282@bhelgaas/

I think this is the best approach in lieu of feedback from those
with knowledge of the hardware / testing on the hardware.

Reviewed-by: Simon Horman <[email protected]>

> ---
> drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c
> index 87f76bac2e463..eb827b86ecae8 100644
> --- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c
> +++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c
> @@ -628,7 +628,13 @@ int qlcnic_fw_create_ctx(struct qlcnic_adapter *dev)
> int i, err, ring;
>
> if (dev->flags & QLCNIC_NEED_FLR) {
> - pci_reset_function(dev->pdev);
> + err = pci_reset_function(dev->pdev);
> + if (err) {
> + dev_err(&dev->pdev->dev,
> + "Adapter reset failed (%d). Please reboot\n",
> + err);
> + return err;
> + }
> dev->flags &= ~QLCNIC_NEED_FLR;
> }
>
> --
> 2.25.1
>

2023-04-07 15:40:11

by Bjorn Helgaas

[permalink] [raw]
Subject: Re: [PATCH net-next v2] qlcnic: check pci_reset_function result

On Fri, Apr 07, 2023 at 11:01:14AM +0200, Simon Horman wrote:
> On Fri, Apr 07, 2023 at 10:18:49AM +0300, Denis Plotnikov wrote:
> > Static code analyzer complains to unchecked return value.
> > The result of pci_reset_function() is unchecked.
> > Despite, the issue is on the FLR supported code path and in that
> > case reset can be done with pcie_flr(), the patch uses less invasive
> > approach by adding the result check of pci_reset_function().

Text could possibly be smoothed out a bit, e.g.:

Static code analyzer complains that the result of
pci_reset_function() is unchecked. Check it and return error if
it fails because the driver relies on the device being reset.

> > Found by Linux Verification Center (linuxtesting.org) with SVACE.
> >
> > Fixes: 7e2cf4feba05 ("qlcnic: change driver hardware interface mechanism")
> > Signed-off-by: Denis Plotnikov <[email protected]>
>
> Thanks Denis,
>
> With reference to,
>
> Link: https://lore.kernel.org/all/20230405193708.GA3632282@bhelgaas/
>
> I think this is the best approach in lieu of feedback from those
> with knowledge of the hardware / testing on the hardware.

Agreed, looks good to me, too. It doesn't look like there's much
activity in this driver (except wider-scale cleanups, etc), so I doubt
anybody could be confident that relying pcie_flr() would be safe.

Seem a *little* weird that this reset is done in .ndo_open() instead
of once at probe-time, but that's a much bigger question and not worth
worrying about.

Reviewed-by: Bjorn Helgaas <[email protected]>

> Reviewed-by: Simon Horman <[email protected]>
>
> > ---
> > drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c | 8 +++++++-
> > 1 file changed, 7 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c
> > index 87f76bac2e463..eb827b86ecae8 100644
> > --- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c
> > +++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_ctx.c
> > @@ -628,7 +628,13 @@ int qlcnic_fw_create_ctx(struct qlcnic_adapter *dev)
> > int i, err, ring;
> >
> > if (dev->flags & QLCNIC_NEED_FLR) {
> > - pci_reset_function(dev->pdev);
> > + err = pci_reset_function(dev->pdev);
> > + if (err) {
> > + dev_err(&dev->pdev->dev,
> > + "Adapter reset failed (%d). Please reboot\n",
> > + err);
> > + return err;
> > + }
> > dev->flags &= ~QLCNIC_NEED_FLR;
> > }
> >
> > --
> > 2.25.1
> >

2023-04-11 11:35:31

by Simon Horman

[permalink] [raw]
Subject: Re: [PATCH net-next v2] qlcnic: check pci_reset_function result

On Tue, Apr 11, 2023 at 01:24:33PM +0200, Paolo Abeni wrote:
> On Fri, 2023-04-07 at 10:18 +0300, Denis Plotnikov wrote:
> > Static code analyzer complains to unchecked return value.
> > The result of pci_reset_function() is unchecked.
> > Despite, the issue is on the FLR supported code path and in that
> > case reset can be done with pcie_flr(), the patch uses less invasive
> > approach by adding the result check of pci_reset_function().
> >
> > Found by Linux Verification Center (linuxtesting.org) with SVACE.
> >
> > Fixes: 7e2cf4feba05 ("qlcnic: change driver hardware interface mechanism")
> > Signed-off-by: Denis Plotnikov <[email protected]>
>
> Any special reason to target the net-next tree? This looks like a -net
> candidate to me?

FWIIW, net would be fine by me.
Sorry for not noticing this during earlier review.

2023-04-11 11:35:49

by Paolo Abeni

[permalink] [raw]
Subject: Re: [PATCH net-next v2] qlcnic: check pci_reset_function result

On Fri, 2023-04-07 at 10:18 +0300, Denis Plotnikov wrote:
> Static code analyzer complains to unchecked return value.
> The result of pci_reset_function() is unchecked.
> Despite, the issue is on the FLR supported code path and in that
> case reset can be done with pcie_flr(), the patch uses less invasive
> approach by adding the result check of pci_reset_function().
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> Fixes: 7e2cf4feba05 ("qlcnic: change driver hardware interface mechanism")
> Signed-off-by: Denis Plotnikov <[email protected]>

Any special reason to target the net-next tree? This looks like a -net
candidate to me?

Thanks!

Paolo

2023-04-12 07:44:22

by patchwork-bot+netdevbpf

[permalink] [raw]
Subject: Re: [PATCH net-next v2] qlcnic: check pci_reset_function result

Hello:

This patch was applied to netdev/net.git (main)
by David S. Miller <[email protected]>:

On Fri, 7 Apr 2023 10:18:49 +0300 you wrote:
> Static code analyzer complains to unchecked return value.
> The result of pci_reset_function() is unchecked.
> Despite, the issue is on the FLR supported code path and in that
> case reset can be done with pcie_flr(), the patch uses less invasive
> approach by adding the result check of pci_reset_function().
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> [...]

Here is the summary with links:
- [net-next,v2] qlcnic: check pci_reset_function result
https://git.kernel.org/netdev/net/c/7573099e10ca

You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html