linux/drivers
Nicholas Bellinger 77d4c74506 target: Make core_disable_device_list_for_node use pre-refactoring lock ordering
So after kicking around commit 547ac4c9c90 around a bit more, a tcm_qla2xxx LUN
unlink OP has generated the following warning:

[   50.386625] qla2xxx [0000:07:00.0]-00af:0: Performing ISP error recovery - ha=ffff880263774000.
[   70.572988] qla2xxx [0000:07:00.0]-8038:0: Cable is unplugged...
[  126.527531] ------------[ cut here ]------------
[  126.532677] WARNING: at kernel/softirq.c:159 local_bh_enable_ip+0x41/0x8c()
[  126.540433] Hardware name: S5520HC
[  126.544248] Modules linked in: tcm_vhost ib_srpt ib_cm ib_sa ib_mad ib_core tcm_qla2xxx tcm_loop tcm_fc libfc iscsi_target_mod target_core_pscsi target_core_file target_core_iblock target_core_mod configfs ipv6 iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi dm_round_robin dm_multipath scsi_dh loop i2c_i801 kvm_intel kvm crc32c_intel i2c_core microcode joydev button iomemory_vsl(O) pcspkr ext3 jbd uhci_hcd lpfc ata_piix libata ehci_hcd qla2xxx mlx4_core scsi_transport_fc scsi_tgt igb [last unloaded: scsi_wait_scan]
[  126.595567] Pid: 3283, comm: unlink Tainted: G           O 3.5.0-rc2+ #33
[  126.603128] Call Trace:
[  126.605853]  [<ffffffff81026b91>] ? warn_slowpath_common+0x78/0x8c
[  126.612737]  [<ffffffff8102c342>] ? local_bh_enable_ip+0x41/0x8c
[  126.619433]  [<ffffffffa03582a2>] ? core_disable_device_list_for_node+0x70/0xe3 [target_core_mod]
[  126.629323]  [<ffffffffa035849f>] ? core_clear_lun_from_tpg+0x88/0xeb [target_core_mod]
[  126.638244]  [<ffffffffa0362ec1>] ? core_tpg_post_dellun+0x17/0x48 [target_core_mod]
[  126.646873]  [<ffffffffa03575ee>] ? core_dev_del_lun+0x26/0x8c [target_core_mod]
[  126.655114]  [<ffffffff810bcbd1>] ? dput+0x27/0x154
[  126.660549]  [<ffffffffa0359aa0>] ? target_fabric_port_unlink+0x3b/0x41 [target_core_mod]
[  126.669661]  [<ffffffffa034a698>] ? configfs_unlink+0xfc/0x14a [configfs]
[  126.677224]  [<ffffffff810b5979>] ? vfs_unlink+0x58/0xb7
[  126.683141]  [<ffffffff810b6ef3>] ? do_unlinkat+0xbb/0x142
[  126.689253]  [<ffffffff81330c75>] ? page_fault+0x25/0x30
[  126.695170]  [<ffffffff81335df9>] ? system_call_fastpath+0x16/0x1b
[  126.702053] ---[ end trace 2f8e5b0a9ec797ef ]---
[  126.756336] qla2xxx [0000:07:00.0]-00af:0: Performing ISP error recovery - ha=ffff880263774000.
[  146.942414] qla2xxx [0000:07:00.0]-8038:0: Cable is unplugged...

So this warning triggered because device_list disable logic is now
holding nacl->device_list_lock w/ spin_lock_irqsave before obtaining
port->sep_alua_lock with only spin_lock_bh..

The original disable logic obtains *deve ahead of dropping the entry
from deve->alua_port_list and then obtains ->device_list_lock to do the
remaining work.  Also, I'm pretty sure this particular warning is being
generated by a demo-mode session in tcm_qla2xxx, and not by explicit
NodeACL MappedLUNs.  The Initiator MappedLUNs are already protected by a
seperate configfs symlink reference back se_lun->lun_group, and the
demo-mode se_node_acl (and associated ->device_list[]) is released
during se_portal_group->tpg_group shutdown.

The following patch drops the extra functional change to disable logic
in commit 547ac4c9c90

Cc: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-07-16 17:35:24 -07:00
..
accessibility
acpi Merge branches 'bugfix-battery', 'bugfix-misc', 'bugfix-rafael', 'bugfix-turbostat', 'bugfix-video' and 'workaround-pss' into release 2012-06-04 00:48:41 -04:00
amba arm-soc: driver specific updates 2012-05-26 12:22:27 -07:00
ata arm-soc: clock driver changes 2012-05-26 12:42:29 -07:00
atm solos-pci: Fix DMA support 2012-05-24 16:22:53 -04:00
auxdisplay
base Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-06-01 10:34:35 -07:00
bcma Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-05-24 11:54:29 -07:00
block mtip32xx: Changes to sysfs entries 2012-05-31 08:46:50 +02:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-05-24 11:54:29 -07:00
cdrom
char char/agp: add another Ironlake host bridge 2012-06-06 17:05:29 +02:00
clk arm-soc: soc specific changes, part 2 2012-05-26 13:05:55 -07:00
clocksource clocksource: em_sti: Add DT support 2012-05-25 11:32:06 +02:00
connector
cpufreq
cpuidle
crypto arm-soc: clock driver changes 2012-05-26 12:42:29 -07:00
dca
devfreq Power management updates for 3.5 2012-05-23 14:07:06 -07:00
dio
dma arm-soc: device tree conversions, part 2 2012-05-26 12:57:47 -07:00
edac Merge branch 'x86/trampoline' into x86/urgent 2012-05-30 12:11:32 -07:00
eisa
extcon Driver core pull for 3.5-rc1 2012-05-22 16:02:13 -07:00
firewire IEEE 1394 (FireWire) subsystem updates post v3.4: 2012-05-24 12:57:47 -07:00
firmware
gpio gpio/samsung: fix the typo 'exynos5_xxx' instead of 'exonys5_xxx' 2012-06-03 21:21:01 -07:00
gpu Revert "drm/i915/crt: Do not rely upon the HPD presence pin" 2012-06-08 14:53:06 -07:00
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2012-05-22 19:22:50 -07:00
hsi
hv Driver core pull for 3.5-rc1 2012-05-22 16:02:13 -07:00
hwmon hwmon/sch56xx: Depend on watchdog for watchdog core functions 2012-05-30 07:56:20 +02:00
hwspinlock
i2c i2c: Add generic I2C multiplexer using pinctrl API 2012-06-04 16:49:43 +02:00
ide
idle
ieee802154 drivers/ieee802154: IEEE 802.15.4 loopback driver 2012-05-16 15:17:08 -04:00
iio
infiniband srpt: use target_execute_cmd for WRITEs in srpt_handle_rdma_comp 2012-07-16 17:35:18 -07:00
input i2c: Split I2C_M_NOSTART support out of I2C_FUNC_PROTOCOL_MANGLING 2012-05-30 10:55:34 +02:00
iommu iommu/amd: Fix deadlock in ppr-handling error path 2012-06-04 12:47:44 +02:00
isdn Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-05-24 11:54:29 -07:00
leds leds: add LM3533 LED driver 2012-05-29 16:22:32 -07:00
lguest
macintosh
md md: 2 fixes for 3.5-rc 2012-06-06 09:49:28 -07:00
media arm-soc: clock driver changes 2012-05-26 12:42:29 -07:00
memory
memstick
message Merge branch 'akpm' (Andrew's patch-bomb) 2012-05-31 18:10:18 -07:00
mfd ARM: ux500: Provide regulator support for SMSC911x via Device Tree 2012-06-01 02:04:46 +02:00
misc MFD changes for 3.5 2012-05-29 11:53:11 -07:00
mmc arm-soc: device tree conversions, part 2 2012-05-26 12:57:47 -07:00
mtd UBI: correct ubi_wl_flush locking 2012-06-07 15:22:21 +03:00
net InfiniBand/RDMA fixes for 3.5-rc2, all in hardware drivers: 2012-06-06 10:45:21 -07:00
nfc NFC: potential integer overflow problem in check_crc() 2012-05-25 11:16:16 -04:00
nubus
of Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2012-05-29 18:27:19 -07:00
oprofile
parisc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2012-05-22 19:22:50 -07:00
parport Driver core pull for 3.5-rc1 2012-05-22 16:02:13 -07:00
pci Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2012-05-29 18:27:19 -07:00
pcmcia
pinctrl pinctrl-nomadik: Allow Device Tree driver probing 2012-06-01 02:03:25 +02:00
platform drivers/platform/x86/acerhdf.c: correct Boris' mail address 2012-06-07 14:43:55 -07:00
pnp
power A bunch of fixes for v3.5, nothing extraordinary. 2012-05-31 12:10:15 -07:00
pps
ps3
ptp Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2012-05-22 19:22:50 -07:00
rapidio rapidio/tsi721: add DMA engine support 2012-05-31 17:49:31 -07:00
regulator MFD changes for 3.5 2012-05-29 11:53:11 -07:00
remoteproc IOMMU Updates for Linux 3.5 2012-05-30 08:49:28 -07:00
rpmsg
rtc Merge branches 'bugfix-battery', 'bugfix-misc', 'bugfix-rafael', 'bugfix-turbostat', 'bugfix-video' and 'workaround-pss' into release 2012-06-04 00:48:41 -04:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2012-05-31 10:51:10 -07:00
sbus
scsi target: remove transport_generic_handle_cdb_map 2012-07-16 17:35:21 -07:00
sfi
sh sh: intc: Kill off special reservation interface. 2012-05-22 19:07:55 +09:00
sn
spi arm-soc: soc specific changes, part 2 2012-05-26 13:05:55 -07:00
ssb ssb: add PCI IDs 0x4322 and 43222 2012-05-16 12:46:37 -04:00
staging Frontswap provides a "transcendent memory" interface for swap pages. 2012-06-04 12:28:45 -07:00
target target: Make core_disable_device_list_for_node use pre-refactoring lock ordering 2012-07-16 17:35:24 -07:00
tc
thermal
tty tty: Revert the tty locking series, it needs more work 2012-06-02 15:21:43 -07:00
uio
usb target: remove transport_generic_handle_cdb_map 2012-07-16 17:35:21 -07:00
uwb
vhost Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-05-16 22:17:37 -04:00
video fbdev updates for 3.5 2012-06-01 16:57:51 -07:00
virt
virtio virtio-mmio: Devices parameter parsing 2012-05-22 12:16:15 +09:30
vlynq
vme
w1 arm-soc: clock driver changes 2012-05-26 12:42:29 -07:00
watchdog watchdog: iTCO_wdt.c: fix printk format warnings 2012-05-30 08:16:48 +02:00
xen Frontswap provides a "transcendent memory" interface for swap pages. 2012-06-04 12:28:45 -07:00
zorro
Kconfig Staging tree pull request for 3.5-rc1 2012-05-22 16:34:21 -07:00
Makefile arm-soc: driver specific updates 2012-05-26 12:22:27 -07:00