RE: [PATCH] qed: fix qed_fill_link() error handling

From: Yuval Mintz
Date: Wed Jun 01 2016 - 06:55:13 EST


> > I think both solutions are equally valid/elegant.
> >
> > Arnd?
>
> I think we can just remove the IS_ENABLED() check there and define the
> IS_PF() macro conditionally to become 'true' if CONFIG_QED_SRIOV is not set,
> like some other drivers do
>
> diff --git a/drivers/net/ethernet/qlogic/qed/qed_main.c
> b/drivers/net/ethernet/qlogic/qed/qed_main.c
> index 287f61c20c19..756176525cf9 100644
> --- a/drivers/net/ethernet/qlogic/qed/qed_main.c
> +++ b/drivers/net/ethernet/qlogic/qed/qed_main.c
> @@ -1110,7 +1110,7 @@ static int qed_get_link_data(struct qed_hwfn *hwfn,
> {
> void *p;
>
> - if (IS_ENABLED(CONFIG_QED_SRIOV) && !IS_PF(hwfn->cdev)) {
> + if (!IS_PF(hwfn->cdev)) {
> qed_vf_get_link_params(hwfn, params);
> qed_vf_get_link_state(hwfn, link);
> qed_vf_get_link_caps(hwfn, link_caps); diff --git
> a/drivers/net/ethernet/qlogic/qed/qed_sriov.h
> b/drivers/net/ethernet/qlogic/qed/qed_sriov.h
> index c8667c65e685..c90b2b6ad969 100644
> --- a/drivers/net/ethernet/qlogic/qed/qed_sriov.h
> +++ b/drivers/net/ethernet/qlogic/qed/qed_sriov.h
> @@ -12,11 +12,13 @@
> #include "qed_vf.h"
> #define QED_VF_ARRAY_LENGTH (3)
>
> +#ifdef CONFIG_QED_SRIOV
> #define IS_VF(cdev) ((cdev)->b_is_vf)
> #define IS_PF(cdev) (!((cdev)->b_is_vf))
> -#ifdef CONFIG_QED_SRIOV
> #define IS_PF_SRIOV(p_hwfn) (!!((p_hwfn)->cdev->p_iov_info))
> #else
> +#define IS_VF(cdev) (0)
> +#define IS_PF(cdev) (1)
> #define IS_PF_SRIOV(p_hwfn) (0)
> #endif
> #define IS_PF_SRIOV_ALLOC(p_hwfn) (!!((p_hwfn)->pf_iov_info))
>
> I don't see why that isn't already the case actually. If this is ok, I'll send an
> updated patch.
>
> For the PF case, we still need to fix the qed_mcp_get_link_params() failure case,
> so the rest of my patch is needed anyway, regardless of how we address the
> warning.
>
> Arnd

I think that would be unsafe with current qede -
qede currently publishes its VFs' PCI device-id as part its MODULE_DEVICE_TABLE,
even if CONFIG_QED_SRIOV isn't enabled [might be the wrong thing to do, but that
how it goes].
Without changing this, if for some reason we'd have an assigned VF to a VM
whose kernel isn't compiled with CONFIG_QED_SRIOV [which is an odd config],
that VM is likely to miserably crash.