shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-04 18:19:28 +09:00
Code Issues Packages Projects Releases Wiki Activity

net: sfp: add mutex to prevent concurrent state checks

Browse Source 
[ Upstream commit 2158e856f5 ]

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>
This commit is contained in:
Robert Hancock
2019-06-07 10:42:36 -06:00
committed by Greg Kroah-Hartman
parent 0dd8efba83
commit 1ee7774527
1 changed files with 5 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
drivers/net/phy/sfp.c
View File

@@ -115,10 +115,11 @@ 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;
@@ -738,6 +739,7 @@ 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;
@@ -763,6 +765,7 @@ 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)
@@ -793,6 +796,7 @@ 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);