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SubjectRE: [PATCH v2] qed: fix qed_fill_link() error handling
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> gcc warns about qed_fill_link possibly accessing uninitialized data:
>
> drivers/net/ethernet/qlogic/qed/qed_main.c: In function 'qed_fill_link':
> drivers/net/ethernet/qlogic/qed/qed_main.c:1170:35: error: 'link_caps' may be
> used uninitialized in this function [-Werror=maybe-uninitialized]
>
> While this warning is only about the specific case of CONFIG_QED_SRIOV being
> disabled but the function getting called for a VF (which should never happen),
> another possibility is that qed_mcp_get_*() fails without returning data.
>
> This rearranges the code so we bail out in either of the two cases and print a
> warning instead of accessing the uninitialized data.
>
> The qed_link_output structure remains untouched in this case, but all callers first
> call memset() on it, so at least we are not leaking stack data then.
>
> As discussed, we also use a compile-time check to ensure we never use any of
> the VF code if CONFIG_QED_SRIOV is disabled, and the PCI device table is
> updated to no longer bind to virtual functions in that configuration.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
>
> ---
> On Wednesday, June 1, 2016 11:10:30 AM CEST Yuval Mintz wrote:
> > Actually, I think VF probe should gracefully fail in that case, as
> > qed_vf_hw_prepare() would simply return -EINVAL.
> > But I can honestly say I've never tested this flow, and I agree
> > there's no reason to allow VF probe in case we're not supporting SRIOV.
>
> ok
>
> > So I guess removing the PCI ID and defining IS_PF to be true in case
> > CONFIG_QED_SRIOV isn't set is the right way to go.
> > Do you want to revise your patch, or do you want me to do it?
>
> I've done the patch below now, please either Ack or modify it the way you like
> and forward it.
>
> Thanks,
>
> Arnd

Perhaps it would have made more sense as a 2-part series; But I'm content with
the changes themselves. I'd let Dave decide whether he wants it split.

Thanks for taking the time fixing this.

Acked-by: Yuval Mintz <Yuval.Mintz@qlogic.com>

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