linux/drivers
Asier Llano 1e4e0767ec net/mpc5200: Fix locking on fec_mpc52xx driver
Fix the locking scheme on the fec_mpc52xx driver.  This device can
receive IRQs from three sources; the FEC itself, the tx DMA, and the
rx DMA.  Mutual exclusion was handled by taking a spin_lock() in the
critical regions, but because the handlers are run with IRQs enabled,
spin_lock() is insufficient and the driver can end up interrupting
a critical region anyway from another IRQ.

Asier Llano discovered that this occurs when an error IRQ is raised
in the middle of handling rx irqs which resulted in an sk_buff memory
leak.

In addition, locking is spotty at best in the driver and inspection
revealed quite a few places with insufficient locking.

This patch is based on Asier's initial work, but reworks a number of
things so that locks are held for as short a time as possible, so
that spin_lock_irqsave() is used everywhere, and so the locks are
dropped when calling into the network stack (because the lock only
protects the hardware interface; not the network stack).

Boot tested on a lite5200 with an NFS root.  Has not been performance
tested.

Signed-off-by: Asier Llano <a.llano@ziv.es>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-12-08 20:29:10 -08:00
..
accessibility
acpi
amba
ata Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev 2009-12-08 08:18:01 -08:00
atm atm: [he] adjust tests to account for sk_wmem_alloc changes 2009-12-08 20:22:31 -08:00
auxdisplay
base
block
bluetooth
cdrom
char Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl-2.6 2009-12-08 07:38:50 -08:00
clocksource
connector
cpufreq
cpuidle
crypto
dca
dio
dma
edac
eisa
firewire Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6 2009-12-08 08:13:10 -08:00
firmware
gpio
gpu
hid
hwmon
i2c i2c-stub: Allow user to disable some commands 2009-12-06 17:06:29 +01:00
ide Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev 2009-12-08 08:18:01 -08:00
idle
ieee1394 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6 2009-12-08 08:13:10 -08:00
ieee802154
infiniband
input Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 2009-12-08 08:15:29 -08:00
isdn
leds Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 2009-12-08 08:15:29 -08:00
lguest
macintosh
mca
md Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl-2.6 2009-12-08 07:38:50 -08:00
media Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6 2009-12-08 07:47:46 -08:00
memstick
message
mfd Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 2009-12-08 08:15:29 -08:00
misc Merge branch 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging 2009-12-08 08:12:16 -08:00
mmc Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 2009-12-08 08:15:29 -08:00
mtd Merge branch 'for-2.6.33' of git://git.kernel.dk/linux-2.6-block 2009-12-08 08:19:16 -08:00
net net/mpc5200: Fix locking on fec_mpc52xx driver 2009-12-08 20:29:10 -08:00
nubus
of
oprofile
parisc
parport Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k 2009-12-08 08:13:35 -08:00
pci
pcmcia Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 2009-12-08 08:15:29 -08:00
platform
pnp
power
pps
ps3
rapidio
regulator
rtc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k 2009-12-08 08:13:35 -08:00
s390 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2009-12-08 07:55:01 -08:00
sbus
scsi Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl-2.6 2009-12-08 07:38:50 -08:00
serial Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm 2009-12-08 08:12:43 -08:00
sfi
sh
sn
spi Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 2009-12-08 08:15:29 -08:00
ssb
staging Merge branch 'for-2.6.33' of git://git.kernel.dk/linux-2.6-block 2009-12-08 08:19:16 -08:00
tc
telephony
thermal
uio
usb Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 2009-12-08 08:15:29 -08:00
uwb
video Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 2009-12-08 08:15:29 -08:00
virtio
vlynq
w1
watchdog Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6 2009-12-08 08:15:29 -08:00
xen
zorro
Kconfig
Makefile