From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: [PATCH net-next v2] ethtool: Protect {get,set}_phy_tunable with PHY device mutex Date: Tue, 22 Nov 2016 13:55:31 -0800 Message-ID: <20161122215531.18212-1-f.fainelli@gmail.com> Cc: davem@davemloft.net, bcm-kernel-feedback-list@broadcom.com, andrew@lunn.ch, allan.nielsen@microsemi.com, raju.lakkaraju@microsemi.com, vivien.didelot@savoirfairelinux.com, Florian Fainelli To: netdev@vger.kernel.org Return-path: Received: from mail-pg0-f65.google.com ([74.125.83.65]:33232 "EHLO mail-pg0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755213AbcKVVzu (ORCPT ); Tue, 22 Nov 2016 16:55:50 -0500 Received: by mail-pg0-f65.google.com with SMTP id 3so3149607pgd.0 for ; Tue, 22 Nov 2016 13:55:50 -0800 (PST) Sender: netdev-owner@vger.kernel.org List-ID: PHY drivers should be able to rely on the caller of {get,set}_tunable to have acquired the PHY device mutex, in order to both serialize against concurrent calls of these functions, but also against PHY state machine changes. All ethtool PHY-level functions do this, except {get,set}_tunable, so we make them consistent here as well. We need to update the Microsemi PHY driver in the same commit to avoid introducing either deadlocks, or lack of proper locking. Fixes: 968ad9da7e0e ("ethtool: Implements ETHTOOL_PHY_GTUNABLE/ETHTOOL_PHY_STUNABLE") Fixes: 310d9ad57ae0 ("net: phy: Add downshift get/set support in Microsemi PHYs driver") Signed-off-by: Florian Fainelli --- Changes in v2: - also patch drivers/net/phy/mscc.c in the same commit drivers/net/phy/mscc.c | 16 +++++----------- net/core/ethtool.c | 4 ++++ 2 files changed, 9 insertions(+), 11 deletions(-) diff --git a/drivers/net/phy/mscc.c b/drivers/net/phy/mscc.c index 92018ba6209e..7a3740c7bf6d 100644 --- a/drivers/net/phy/mscc.c +++ b/drivers/net/phy/mscc.c @@ -115,10 +115,9 @@ static int vsc85xx_downshift_get(struct phy_device *phydev, u8 *count) int rc; u16 reg_val; - mutex_lock(&phydev->lock); rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_EXTENDED); if (rc != 0) - goto out_unlock; + goto out; reg_val = phy_read(phydev, MSCC_PHY_ACTIPHY_CNTL); reg_val &= DOWNSHIFT_CNTL_MASK; @@ -128,9 +127,7 @@ static int vsc85xx_downshift_get(struct phy_device *phydev, u8 *count) *count = ((reg_val & ~DOWNSHIFT_EN) >> DOWNSHIFT_CNTL_POS) + 2; rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_STANDARD); -out_unlock: - mutex_unlock(&phydev->lock); - +out: return rc; } @@ -150,23 +147,20 @@ static int vsc85xx_downshift_set(struct phy_device *phydev, u8 count) count = (((count - 2) << DOWNSHIFT_CNTL_POS) | DOWNSHIFT_EN); } - mutex_lock(&phydev->lock); rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_EXTENDED); if (rc != 0) - goto out_unlock; + goto out; reg_val = phy_read(phydev, MSCC_PHY_ACTIPHY_CNTL); reg_val &= ~(DOWNSHIFT_CNTL_MASK); reg_val |= count; rc = phy_write(phydev, MSCC_PHY_ACTIPHY_CNTL, reg_val); if (rc != 0) - goto out_unlock; + goto out; rc = vsc85xx_phy_page_set(phydev, MSCC_PHY_PAGE_STANDARD); -out_unlock: - mutex_unlock(&phydev->lock); - +out: return rc; } diff --git a/net/core/ethtool.c b/net/core/ethtool.c index e9b4556751ff..0adb3bec5b5a 100644 --- a/net/core/ethtool.c +++ b/net/core/ethtool.c @@ -2466,7 +2466,9 @@ static int get_phy_tunable(struct net_device *dev, void __user *useraddr) data = kmalloc(tuna.len, GFP_USER); if (!data) return -ENOMEM; + mutex_lock(&phydev->lock); ret = phydev->drv->get_tunable(phydev, &tuna, data); + mutex_unlock(&phydev->lock); if (ret) goto out; useraddr += sizeof(tuna); @@ -2501,7 +2503,9 @@ static int set_phy_tunable(struct net_device *dev, void __user *useraddr) ret = -EFAULT; if (copy_from_user(data, useraddr, tuna.len)) goto out; + mutex_lock(&phydev->lock); ret = phydev->drv->set_tunable(phydev, &tuna, data); + mutex_unlock(&phydev->lock); out: kfree(data); -- 2.9.3