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| author | Robert Hancock <hancock@sedsystems.ca> | 2019-06-07 10:42:36 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-07-26 09:14:05 +0200 |
| commit | c7bf2df4504439480afce68e84490d5d976deebc (patch) | |
| tree | 765d183a5a2bbbbcf58f5d364b10cf45b1ca6c4b /drivers | |
| parent | fa4059c5497e42fd9b91da1d32e14792f998e985 (diff) | |
| download | linux-stable-c7bf2df4504439480afce68e84490d5d976deebc.tar.gz linux-stable-c7bf2df4504439480afce68e84490d5d976deebc.tar.bz2 linux-stable-c7bf2df4504439480afce68e84490d5d976deebc.zip | |
net: sfp: add mutex to prevent concurrent state checks
[ Upstream commit 2158e856f56bb762ef90f3ec244d41a519826f75 ]
sfp_check_state can potentially be called by both a threaded IRQ handler
and delayed work. If it is concurrently called, it could result in
incorrect state management. Add a st_mutex to protect the state - this
lock gets taken outside of code that checks and handle state changes, and
the existing sm_mutex nests inside of it.
Suggested-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Robert Hancock <hancock@sedsystems.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/phy/sfp.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c index 8807a806cc47..418522aa2f71 100644 --- a/drivers/net/phy/sfp.c +++ b/drivers/net/phy/sfp.c @@ -185,10 +185,11 @@ struct sfp { struct gpio_desc *gpio[GPIO_MAX]; bool attached; + struct mutex st_mutex; /* Protects state */ unsigned int state; struct delayed_work poll; struct delayed_work timeout; - struct mutex sm_mutex; + struct mutex sm_mutex; /* Protects state machine */ unsigned char sm_mod_state; unsigned char sm_dev_state; unsigned short sm_state; @@ -1718,6 +1719,7 @@ static void sfp_check_state(struct sfp *sfp) { unsigned int state, i, changed; + mutex_lock(&sfp->st_mutex); state = sfp_get_state(sfp); changed = state ^ sfp->state; changed &= SFP_F_PRESENT | SFP_F_LOS | SFP_F_TX_FAULT; @@ -1743,6 +1745,7 @@ static void sfp_check_state(struct sfp *sfp) sfp_sm_event(sfp, state & SFP_F_LOS ? SFP_E_LOS_HIGH : SFP_E_LOS_LOW); rtnl_unlock(); + mutex_unlock(&sfp->st_mutex); } static irqreturn_t sfp_irq(int irq, void *data) @@ -1773,6 +1776,7 @@ static struct sfp *sfp_alloc(struct device *dev) sfp->dev = dev; mutex_init(&sfp->sm_mutex); + mutex_init(&sfp->st_mutex); INIT_DELAYED_WORK(&sfp->poll, sfp_poll); INIT_DELAYED_WORK(&sfp->timeout, sfp_timeout); |