[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20240602141524.iap3b6w2dxilwzjg@skbuf>
Date: Sun, 2 Jun 2024 17:15:24 +0300
From: Vladimir Oltean <olteanv@...il.com>
To: Tristram.Ha@...rochip.com
Cc: Arun Ramadoss <arun.ramadoss@...rochip.com>,
Woojung Huh <woojung.huh@...rochip.com>,
Andrew Lunn <andrew@...n.ch>,
Vivien Didelot <vivien.didelot@...il.com>,
Florian Fainelli <f.fainelli@...il.com>,
"David S. Miller" <davem@...emloft.net>,
Eric Dumazet <edumazet@...gle.com>,
Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>,
UNGLinuxDriver@...rochip.com, netdev@...r.kernel.org,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH v1 net] net: dsa: microchip: fix wrong register write
when masking interrupt
On Thu, May 30, 2024 at 06:39:13PM -0700, Tristram.Ha@...rochip.com wrote:
> From: Tristram Ha <tristram.ha@...rochip.com>
>
> Initially the macro REG_SW_PORT_INT_MASK__4 is defined as 0x001C in
> ksz9477_reg.h and REG_PORT_INT_MASK is defined as 0x#01F. Because the
> global and port interrupt handling is about the same the new
> REG_SW_PORT_INT_MASK__1 is defined as 0x1F in ksz_common.h. This works
> as only the least significant bits have effect. As a result the 32-bit
> write needs to be changed to 8-bit.
>
> Fixes: e1add7dd6183 ("net: dsa: microchip: use common irq routines for girq and pirq")
> Signed-off-by: Tristram Ha <tristram.ha@...rochip.com>
> ---
> v1
> - clarify the reason to change the code
After v1 comes v2.
>
> drivers/net/dsa/microchip/ksz_common.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
> index 1e0085cd9a9a..3ad0879b00cd 100644
> --- a/drivers/net/dsa/microchip/ksz_common.c
> +++ b/drivers/net/dsa/microchip/ksz_common.c
> @@ -2185,7 +2185,7 @@ static void ksz_irq_bus_sync_unlock(struct irq_data *d)
> struct ksz_device *dev = kirq->dev;
> int ret;
>
> - ret = ksz_write32(dev, kirq->reg_mask, kirq->masked);
> + ret = ksz_write8(dev, kirq->reg_mask, kirq->masked);
> if (ret)
> dev_err(dev->dev, "failed to change IRQ mask\n");
>
> --
> 2.34.1
>
What is the user-visible functional impact of the 32-bit access? Justify
why this is a bug worth sending to stable kernels please.
FWIW, struct ksz_irq operates on 16-bit registers.
Powered by blists - more mailing lists