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Subject[PATCH 0/2] net: Fix crashes due to activity during suspend
Date
	Hi all,

If an Ethernet device is used while the device is suspended, the system may
crash.

E.g. on sh73a0/kzm9g and r8a73a4/ape6evm, the external Ethernet chip is
driven by a PM controlled clock. If the Ethernet registers are accessed
while the clock is not running, the system will crash with an imprecise
external abort.

This patch series fixes two of such crashes:
1. The first patch prevents the PHY polling state machine from accessing
PHY registers while a device is suspended,
2. The second patch prevents the net core from trying to transmit packets
when an smsc911x device is suspended.

Both crashes can be reproduced on sh73a0/kzm9g and r8a73a4/ape6evm during
s2ram (rarely), or by using pm_test (more likely to trigger):

# echo 0 > /sys/module/printk/parameters/console_suspend
# echo platform > /sys/power/pm_test
# echo mem > /sys/power/state

With this series applied, my test systems survive a loop of 100 test
suspends.

Thanks for your comments!

Geert Uytterhoeven (2):
net: phy: Freeze PHY polling before suspending devices
net: smsc911x: Quiten netif during suspend

drivers/net/ethernet/smsc/smsc911x.c | 15 ++++++++++++++-
drivers/net/phy/phy.c | 12 +++++++-----
2 files changed, 21 insertions(+), 6 deletions(-)

--
2.7.4

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds

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