linux/drivers
Supriya Karanth 39287076e4 usb: musb: Reselect index reg in interrupt context
musb INDEX register is getting modified/corrupted during temporary
un-locking in a SMP system. Set this register with proper value
after re-acquiring the lock

Scenario:
---------
CPU1 is handling a data transfer completion interrupt received for
the CLASS1 EP
CPU2 is handling a CLASS2 thread which is queuing data to musb for
transfer

Below is the error sequence:

         CPU1                   |             CPU2
--------------------------------------------------------------------
Data transfer completion inter- |
rupt recieved.                  |
                                |
musb INDEX reg set to CLASS1 EP |
                                |
musb LOCK is acquired.          |
                                |
                                | CLASS2 thread queues data.
                                |
                                | CLASS2 thread tries to acquire musb
                                | LOCK but lock is already taken by
                                | CLASS1, so CLASS2 thread is
                                | spinning.
                                |
From Interrupt Context musb     |
giveback function is called     |
                                |
The giveback function releases  | CLASS2 thread now acquires LOCK
LOCK                            |
                                |
ClASS1 Request's completion cal-| ClASS2 schedules the data transfer and
lback is called                 | sets the MUSB INDEX to Class2 EP number
                                |
Interrupt handler for CLASS1 EP |
tries to acquire LOCK and is    |
spinning                        |
                                |
Interrupt for Class1 EP acquires| Class2 completes the scheduling etc and
the MUSB LOCK                   | releases the musb LOCK
                                |
Interrupt for Class1 EP schedul-|
es the next data transfer       |
but musb INDEX register is still|
set to CLASS2 EP                |

Since the MUSB INDEX register is set to a different endpoint, we
read and modify the wrong registers. Hence data transfer will not
happen properly. This results in unpredictable behavior

So, the MUSB INDEX register is set to proper value again when
interrupt re-acquires the lock

Cc: stable@vger.kernel.org
Signed-off-by: Supriya Karanth <supriya.karanth@stericsson.com>
Signed-off-by: Praveena Nadahally <praveen.nadahally@stericsson.com>
Reviewed-by: srinidhi kasagar <srinidhi.kasagar@stericsson.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
2012-02-24 12:23:02 +02:00
..
accessibility module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
acpi Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2012-01-18 15:51:48 -08:00
amba Merge branch 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm 2012-01-08 13:10:57 -08:00
ata [libata] ata_piix: Add Toshiba Satellite Pro A120 to the quirks list 2012-01-17 20:50:53 -05:00
atm module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
auxdisplay
base Merge branch 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm 2012-01-16 15:02:30 -08:00
bcma bcma: connect the bcma bus suspend/resume to the bcma driver suspend/resume 2012-01-17 09:54:08 -05:00
block nvme: fix merge error due to change of 'make_request_fn' fn type 2012-01-18 15:41:27 -08:00
bluetooth module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
cdrom block: add and use scsi_blk_cmd_ioctl 2012-01-14 15:07:24 -08:00
char tpm: fix (ACPI S3) suspend regression 2012-01-18 15:50:17 -08:00
clk
clocksource Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm 2012-01-06 18:15:25 -08:00
connector
cpufreq Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq 2012-01-11 18:53:33 -08:00
cpuidle
crypto Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2012-01-10 22:01:27 -08:00
dca
devfreq
dio
dma Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma 2012-01-17 18:40:24 -08:00
edac module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
eisa
firewire module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
firmware Merge commit '070680218379e15c1901f4bf21b98e3cbf12b527' into stable/for-linus-fixes-3.3 2012-01-12 11:53:55 -05:00
gpio gpio: tps65910: Use correct offset for gpio initialization 2012-01-18 13:48:43 -07:00
gpu nouveau: Support Optimus models for vga_switcheroo 2012-01-13 09:09:15 +00:00
hid module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
hv Merge branch 'usb-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb 2012-01-09 12:09:47 -08:00
hwmon hwmon: (adm1031) Fix coding style issues 2012-01-16 22:51:48 +01:00
hwspinlock
i2c Merge branches 'for-33/i2c/eg20t' and 'for-33/i2c/omap' into for-linus/i2c-33 2012-01-17 23:30:41 +00:00
ide block: add and use scsi_blk_cmd_ioctl 2012-01-14 15:07:24 -08:00
idle Merge branches 'einj', 'intel_idle', 'misc', 'srat' and 'turbostat-ivb' into release 2012-01-18 01:15:54 -05:00
ieee802154
infiniband Merge branch 'for-next-merge' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2012-01-18 16:29:42 -08:00
input Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1 2012-01-14 12:32:16 -08:00
iommu Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu 2012-01-10 11:08:21 -08:00
isdn Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1 2012-01-14 12:32:16 -08:00
leds Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1 2012-01-14 12:32:16 -08:00
lguest lguest: Make sure interrupt is allocated ok by lguest_setup_irq 2012-01-12 15:44:47 +10:30
macintosh module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
mca
md Merge branch 'for-3.3/core' of git://git.kernel.dk/linux-block 2012-01-15 12:24:45 -08:00
media Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2012-01-18 12:53:54 -08:00
memstick module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
message SCSI updates for post 3.2 merge window 2012-01-10 10:36:08 -08:00
mfd Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1 2012-01-14 12:32:16 -08:00
misc Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma 2012-01-17 18:40:24 -08:00
mmc Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma 2012-01-17 18:40:24 -08:00
mtd Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma 2012-01-17 18:40:24 -08:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-01-17 22:26:41 -08:00
nfc Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core 2012-01-07 12:03:30 -08:00
nubus
of 2nd set of device tree changes for v3.3 2012-01-14 13:25:55 -08:00
oprofile Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2012-01-06 08:02:58 -08:00
parisc Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci 2012-01-11 18:50:26 -08:00
parport Autogenerated GPG tag for Rusty D1ADB8F1: 15EE 8D6C AB0E 7F0C F999 BFCB D920 0E6C D1AD B8F1 2012-01-14 12:32:16 -08:00
pci Merge branch 'for-linus' of git://selinuxproject.org/~jmorris/linux-security 2012-01-14 18:36:33 -08:00
pcmcia Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2012-01-14 13:05:21 -08:00
pinctrl pinctrl: remove unnecessary max pin number 2012-01-03 09:10:09 +01:00
platform module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
pnp PNP: work around Dell 1536/1546 BIOS MMCONFIG bug that breaks USB 2012-01-06 12:11:20 -08:00
power module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
pps
ps3
ptp
rapidio
regulator Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6 2012-01-13 20:43:32 -08:00
rtc Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6 2012-01-13 20:43:32 -08:00
s390 module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
sbus
scsi SCSI updates on 20120118 2012-01-18 12:35:17 -08:00
sfi
sh SH/R-Mobile updates for 3.3 merge window. 2012-01-11 23:29:20 -08:00
sn
spi Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma 2012-01-17 18:40:24 -08:00
ssb
staging Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2012-01-15 12:49:56 -08:00
target
tc
telephony
thermal
tty Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma 2012-01-17 18:40:24 -08:00
uio Merge branch 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci 2012-01-11 18:50:26 -08:00
usb usb: musb: Reselect index reg in interrupt context 2012-02-24 12:23:02 +02:00
uwb Merge branch 'usb-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb 2012-01-09 12:09:47 -08:00
vhost vhost-net: add module alias (v2.1) 2012-01-13 10:12:23 -08:00
video Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma 2012-01-17 18:40:24 -08:00
virt
virtio virtio: balloon: Add freeze, restore handlers to support S4 2012-01-12 15:44:47 +10:30
vlynq
w1
watchdog module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
xen xen: using EXPORT_SYMBOL requires including export.h 2012-01-18 15:37:49 -08:00
zorro misc latin1 to utf8 conversions 2012-01-02 13:04:55 +01:00
Kconfig
Makefile mmc: sdhci-pci: add platform data 2012-01-11 23:58:47 -05:00