[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <1388686249.9947.12.camel@bwh-desktop.uk.level5networks.com>
Date: Thu, 2 Jan 2014 18:10:49 +0000
From: Ben Hutchings <bhutchings@...arflare.com>
To: Jeff Kirsher <jeffrey.t.kirsher@...el.com>
CC: <davem@...emloft.net>, Mark Rustad <mark.d.rustad@...el.com>,
<netdev@...r.kernel.org>, <gospo@...hat.com>, <sassmann@...hat.com>
Subject: Re: [net-next 3/9] ixgbe: Check register reads for adapter removal
On Thu, 2014-01-02 at 01:33 -0800, Jeff Kirsher wrote:
> From: Mark Rustad <mark.d.rustad@...el.com>
>
> When CONFIG_IXGBE_LER is defined, check all register reads for
> adapter removal by checking the status register after any register
> read that returns 0xFFFFFFFF. Since the status register will never
> return 0xFFFFFFFF unless the adapter is removed, such a value from
> a status register read confirms the removal.
>
> Signed-off-by: Mark Rustad <mark.d.rustad@...el.com>
> Tested-by: Phil Schmitt <phillip.j.schmitt@...el.com>
> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@...el.com>
> ---
> drivers/net/ethernet/intel/ixgbe/ixgbe.h | 1 +
> drivers/net/ethernet/intel/ixgbe/ixgbe_common.h | 21 +++++++++++++
> drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 40 ++++++++++++++++++++++---
> 3 files changed, 58 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe.h b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
> index 9e9b8d0..ad34757 100644
> --- a/drivers/net/ethernet/intel/ixgbe/ixgbe.h
> +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe.h
[...]
> @@ -141,7 +150,19 @@ static inline void IXGBE_WRITE_REG64(struct ixgbe_hw *hw, u32 reg, u64 value)
>
> static inline u32 IXGBE_READ_REG(struct ixgbe_hw *hw, u32 reg)
> {
> +#ifdef CONFIG_IXGBE_LER
> + u8 __iomem *reg_addr = hw->hw_addr;
This should have an ACCESS_ONCE() so the compiler definitely won't read
hw->hw_addr a second time after it's been validated.
Ben.
> + u32 value;
> +
> + if (IXGBE_REMOVED(reg_addr))
> + return IXGBE_FAILED_READ_REG;
> + value = readl(reg_addr + reg);
> + if (unlikely(value == IXGBE_FAILED_READ_REG))
> + ixgbe_check_remove(hw, reg);
> + return value;
> +#else
> return readl(hw->hw_addr + reg);
> +#endif /* CONFIG_IXGBE_LER */
> }
[...]
--
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists