On 4/25/24 15:27, Doug Berger wrote:
The UMAC_CMD register is written from different execution contexts and has insufficient synchronization protections to prevent possible corruption. Of particular concern are the acceses from the phy_device delayed work context used by the adjust_link call and the BH context that may be used by the ndo_set_rx_mode call.
A spinlock is added to the driver to protect contended register accesses (i.e. reg_lock) and it is used to synchronize accesses to UMAC_CMD.
Fixes: 1c1008c793fa ("net: bcmgenet: add main driver file") Cc: stable@vger.kernel.org Signed-off-by: Doug Berger opendmb@gmail.com
Acked-by: Florian Fainelli florian.fainelli@broadcom.com
As a bug fix this is totally fine. I believe there could be an improvement made in 'net-next' whereby we introduce an unimac_rmw_locked() or something that essentially does:
void unimac_rmw_locked(struct bcmgenet_priv *priv, u32 offset, u32 mask_clear, u32 mask_set) { u32 reg; spin_lock_bh(&priv->reg_lock); reg = bcmgenet_umac_readl(priv, offset); reg &= ~mask_clear; reg |= mask_set; bcmgenet_umac_writel(priv, reg, offset); spin_unlock_bh(&priv->reg_lock); }
At least a couple of callers could benefit from it. Thanks!