Kernel/linux-next
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git synced 2025-01-18 06:15:12 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

net: phy: fix race in genphy_update_link

Browse Source 
In phy_start_aneg() autoneg is started, and immediately after that
link and autoneg status are read. As reported in [0] it can happen that
at time of this read the PHY has reset the "aneg complete" bit but not
yet the "link up" bit, what can result in a false link-up detection.
To fix this don't report link as up if we're in aneg mode and PHY
doesn't signal "aneg complete".

[0] https://marc.info/?t=156413509900003&r=1&w=2

Fixes: 4950c2ba49cc ("net: phy: fix autoneg mismatch case in genphy_read_status")
Reported-by: liuyonglong <liuyonglong@huawei.com>
Tested-by: liuyonglong <liuyonglong@huawei.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Heiner Kallweit 2019-07-31 23:05:10 +02:00 committed by David S. Miller
parent 2802d2cf24
commit aa6b195615
1 changed files with 6 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

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

@ -1774,6 +1774,12 @@ done:
phydev->link = status & BMSR_LSTATUS ? 1 : 0;
phydev->autoneg_complete = status & BMSR_ANEGCOMPLETE ? 1 : 0;
/* Consider the case that autoneg was started and "aneg complete"
* bit has been reset, but "link up" bit not yet.
*/
if (phydev->autoneg == AUTONEG_ENABLE && !phydev->autoneg_complete)
phydev->link = 0;
return 0;
}
EXPORT_SYMBOL(genphy_update_link);