NeilBrown c8c00a6915 Remove deadlock potential in md_open ... A recent commit: commit 449aad3e25 introduced the possibility of an A-B/B-A deadlock between bd_mutex and reconfig_mutex. __blkdev_get holds bd_mutex while calling md_open which takes reconfig_mutex, do_md_run is always called with reconfig_mutex held, and it now takes bd_mutex in the call the revalidate_disk. This potential deadlock was not caught by lockdep due to the use of mutex_lock_interruptible_nexted which was introduced by commit d63a5a74de do avoid a warning of an impossible deadlock. It is quite possible to split reconfig_mutex in to two locks. One protects the array data structures while it is being reconfigured, the other ensures that an array is never even partially open while it is being deactivated. In particular, the second lock prevents an open from completing between the time when do_md_stop checks if there are any active opens, and the time when the array is either set read-only, or when ->pers is set to NULL. So we can be certain that no IO is in flight as the array is being destroyed. So create a new lock, open_mutex, just to ensure exclusion between 'open' and 'stop'. This avoids the deadlock and also avoids the lockdep warning mentioned in commit d63a5a74d Reported-by: "Mike Snitzer" <snitzer@gmail.com> Reported-by: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: NeilBrown <neilb@suse.de>		2009-08-10 12:50:52 +10:00
..
accessibility
acpi	Merge branch 'misc-2.6.31' into release	2009-08-02 12:55:51 -04:00
amba	[ARM] amba: fix amba device resources	2009-07-05 22:39:08 +01:00
ata	libata: accept late unlocking of HPA	2009-07-28 21:07:09 -04:00
atm
auxdisplay
base	driver core: sysdev: do not send KOBJ_ADD uevent if kobject_init_and_add fails	2009-07-28 13:45:22 -07:00
block	mg_disk: Add missing ready status check on mg_write()	2009-07-28 08:57:33 +02:00
bluetooth	headers: smp_lock.h redux	2009-07-12 12:22:34 -07:00
cdrom
char	Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6	2009-08-04 15:39:43 -07:00
clocksource	clocksource: sh_tmu: Make undefined TCOR behaviour less undefined.	2009-06-24 21:08:11 +09:00
connector	connector: maintainer/mail update.	2009-07-21 12:43:51 -07:00
cpufreq	[CPUFREQ] Make cpufreq suspend code conditional on powerpc.	2009-08-04 14:32:11 -04:00
cpuidle
crypto
dca
dio
dma	Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx	2009-07-30 16:46:31 -07:00
edac	amd64_edac: print debug statements only on error	2009-08-04 12:10:06 +02:00
eisa
firewire	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6	2009-07-06 14:03:44 -07:00
firmware
gpio	headers: smp_lock.h redux	2009-07-12 12:22:34 -07:00
gpu	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel	2009-08-07 19:03:59 -07:00
hid	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid	2009-07-22 09:30:07 -07:00
hwmon	hwmon: (asus_atk0110) Fix upper limit readings	2009-07-28 16:31:39 +02:00
i2c	i2c-omap: OMAP3430 Silicon Errata 1.153	2009-07-30 01:03:24 +01:00
ide	ide-tape: Don't leak kernel stack information	2009-07-21 20:36:25 -07:00
idle
ieee1394	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6	2009-07-06 14:03:44 -07:00
ieee802154
infiniband	Merge branches 'ehca', 'misc', 'mlx4', 'mthca' and 'nes' into for-linus	2009-06-23 10:38:47 -07:00
input	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input	2009-08-07 10:42:14 -07:00
isdn	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6	2009-08-04 15:38:34 -07:00
leds	Update Yoichi Yuasa's e-mail address	2009-07-03 15:45:29 +01:00
lguest	lguest and virtio: cleanup struct definitions to Linux style.	2009-07-30 16:03:46 +09:30
macintosh	powerpc/pmac: Fix DMA ops for MacIO devices	2009-06-26 14:37:25 +10:00
mca
md	Remove deadlock potential in md_open	2009-08-10 12:50:52 +10:00
media	V4L/DVB (12303): cx23885: check pointers before dereferencing in dprintk macro	2009-07-24 14:03:32 -03:00
memstick
message	fusion: mptsas, fix lock imbalance	2009-06-22 08:54:14 -05:00
mfd	mfd: twl4030 irq fixes	2009-08-04 20:31:32 +02:00
misc	cb710: use SG_MITER_TO_SG/SG_MITER_FROM_SG	2009-07-31 12:28:46 +02:00
mmc	drivers/mmc: correct error-handling code	2009-08-07 10:39:56 -07:00
mtd	mtd: mtdblock: introduce mtdblks_lock	2009-08-03 14:25:00 +01:00
net	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6	2009-08-04 15:38:34 -07:00
nubus
of	of/mdio: Add support function for Ethernet fixed-link property	2009-07-22 09:27:18 -07:00
oprofile	oprofile: reset bt_lost_no_mapping with other stats	2009-07-10 12:35:36 +02:00
parisc	parisc: hppb.c - fix printk format strings	2009-08-02 15:42:39 +02:00
parport	parport/serial: add support for NetMos 9901 Multi-IO card	2009-06-30 18:55:59 -07:00
pci	intel-iommu: Fix enabling snooping feature by mistake	2009-08-06 11:35:50 +01:00
pcmcia	Remove multiple KERN_ prefixes from printk formats	2009-07-08 10:30:03 -07:00
platform	Merge branch 'bugzilla-13825' into release	2009-08-02 12:36:01 -04:00
pnp	Merge branches 'acerhdf', 'acpi-pci-bind', 'bjorn-pci-root', 'bugzilla-12904', 'bugzilla-13121', 'bugzilla-13396', 'bugzilla-13533', 'bugzilla-13612', 'c3_lock', 'hid-cleanups', 'misc-2.6.31', 'pdc-leak-fix', 'pnpacpi', 'power_nocheck', 'thinkpad_acpi', 'video' and 'wmi' into release	2009-06-24 01:19:50 -04:00
power	Merge git://git.infradead.org/users/cbou/battery-2.6.31	2009-07-30 16:45:53 -07:00
pps
ps3
rapidio
regulator
rtc	rtc: mark if rtc-cmos drivers were successfully registered	2009-07-29 19:10:35 -07:00
s390	Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6	2009-08-04 15:38:10 -07:00
sbus
scsi	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6	2009-08-04 15:38:34 -07:00
serial	Merge master.kernel.org:/home/rmk/linux-2.6-arm	2009-08-07 10:46:51 -07:00
sh
sn
spi	spi: omap2_mcspi rxdma bugfix	2009-07-29 19:10:35 -07:00
ssb	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6	2009-07-09 20:33:18 -07:00
staging	Staging: rspiusb: Fix buffer overflow	2009-08-07 16:12:03 -07:00
tc
telephony	headers: smp_lock.h redux	2009-07-12 12:22:34 -07:00
thermal
uio
usb	USB: fix oops on disconnect in cdc-acm	2009-08-07 16:05:14 -07:00
uwb
video	i.MX31: fix framebuffer locking regressions	2009-08-07 10:39:56 -07:00
virtio	virtio: refactor find_vqs	2009-07-30 16:03:45 +09:30
vlynq	vlynq: fix typo in Kconfig to enable debugging	2009-07-06 13:57:03 -07:00
w1	drivers/w1/masters/omap_hdq.c: fix missing mutex unlock	2009-08-07 10:39:55 -07:00
watchdog	Merge master.kernel.org:/home/rmk/linux-2.6-arm	2009-08-07 10:46:51 -07:00
xen	xen: Use kcalloc() in xen_init_IRQ()	2009-07-01 11:19:47 +02:00
zorro
Kconfig
Makefile