linux/drivers
Vaibhav Jain 1b5df59e50 cxl: Fix possible idr warning when contexts are released
An idr warning is reported when a context is release after the capi card
is unbound from the cxl driver via sysfs. Below are the steps to
reproduce:

1. Create multiple afu contexts in an user-space application using libcxl.
2. Unbind capi card from cxl using command of form
   echo <capi-card-pci-addr> > /sys/bus/pci/drivers/cxl-pci/unbind
3. Exit/kill the application owning afu contexts.

After above steps a warning message is usually seen in the kernel logs
of the form "idr_remove called for id=<context-id> which is not
allocated."

This is caused by the function cxl_release_afu which destroys the
contexts_idr table. So when a context is release no entry for context pe
is found in the contexts_idr table and idr code prints this warning.

This patch fixes this issue by increasing & decreasing the ref-count on
the afu device when a context is initialized or when its freed
respectively. This prevents the afu from being released until all the
afu contexts have been released. The patch introduces two new functions
namely cxl_afu_get/put that manage the ref-count on the afu device.

Also the patch removes code inside cxl_dev_context_init that increases ref
on the afu device as its guaranteed to be alive during this function.

Reported-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-24 14:21:27 +11:00
..
accessibility
acpi Merge branches 'acpi-smbus', 'acpi-ec' and 'acpi-pci' 2015-11-20 01:22:52 +01:00
amba
android
ata SCSI misc on 20151113 2015-11-13 20:35:54 -08:00
atm
auxdisplay
base Merge branch 'pm-sleep' 2015-11-20 01:22:33 +01:00
bcma
block Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2015-11-13 09:24:40 -08:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-11-10 18:11:41 -08:00
bus ARM: SoC driver updates for v4.4 2015-11-10 15:00:03 -08:00
cdrom
char ipmi watchdog : add panic_wdt_timeout parameter 2015-11-16 06:28:43 -06:00
clk h8300 update for v4.4 2015-11-12 15:26:39 -08:00
clocksource clocksource: Disallow drivers for ARCH_USES_GETTIMEOFFSET 2015-11-16 19:07:08 +01:00
connector mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd 2015-11-06 17:50:42 -08:00
cpufreq Merge branches 'pm-cpufreq' and 'acpi-cppc' 2015-11-20 01:22:10 +01:00
cpuidle
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2015-11-17 09:40:05 -08:00
dca
devfreq
dio
dma dmaengine: at_hdmac: use %pad format string for dma_addr_t 2015-11-16 09:21:05 +05:30
dma-buf dma-buf/fence: add fence_wait_any_timeout function v2 2015-10-30 01:16:16 -04:00
edac asm-generic cleanups 2015-11-06 14:22:15 -08:00
eisa
extcon Merge branches 'ib-extcon-mfd-4.4', 'ib-mfd-i2c-v4.4', 'ib-mfd-power-4.4', 'ib-mfd-regmap-4.4' and 'ib-mfd-regulator-4.4' into ibs-for-mfd-merged 2015-10-26 14:48:22 +00:00
firewire IEEE 1394 subsystem patch: 2015-11-11 10:21:34 -08:00
firmware ARM: SoC driver updates for v4.4 2015-11-10 15:00:03 -08:00
fmc
fpga fpga: socfpga: Fix check of return value of devm_request_irq 2015-10-29 15:20:25 -07:00
gpio asm-generic cleanups 2015-11-06 14:22:15 -08:00
gpu Merge tag 'drm-intel-fixes-2015-11-19' of git://anongit.freedesktop.org/drm-intel into drm-fixes 2015-11-20 09:45:31 +10:00
hid HID: wacom: fixup quirks setup for WACOM_DEVICETYPE_PAD 2015-11-17 00:24:14 +01:00
hsi hsi: controllers:remove redundant code 2015-10-30 16:10:40 +01:00
hv drivers/hv: share Hyper-V SynIC constants with userspace 2015-11-04 16:24:33 +01:00
hwmon hwmon: (scpi) skip unsupported sensors properly 2015-11-16 09:59:50 -08:00
hwspinlock
hwtracing Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2015-11-13 20:04:17 -08:00
i2c i2c: i801: add Intel Lewisburg device IDs 2015-11-20 16:22:21 +01:00
ide mm, page_alloc: rename __GFP_WAIT to __GFP_RECLAIM 2015-11-06 17:50:42 -08:00
idle
iio First set of IIO fixes for the 4.4 cycle. 2015-11-18 13:15:50 -08:00
infiniband SCSI misc on 20151113 2015-11-13 20:35:54 -08:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2015-11-13 21:41:14 -08:00
iommu s390/pci_dma: handle dma table failures 2015-11-09 09:10:49 +01:00
ipack
irqchip irqchip/gic: Add save/restore of the active state 2015-11-17 14:25:59 +01:00
isdn TTY/Serial driver patches for 4.4-rc1 2015-11-04 21:35:12 -08:00
leds spi: Updates for v4.4 2015-11-05 13:15:12 -08:00
lguest
lightnvm block: change ->make_request_fn() and users to return a queue cookie 2015-11-07 10:40:46 -07:00
macintosh
mailbox mailbox: mailbox-test: avoid reading iomem twice 2015-11-04 14:03:04 +05:30
mcb mcb: Destroy IDA on module unload 2015-10-29 09:02:16 +09:00
md Merge branch 'for-4.4/io-poll' of git://git.kernel.dk/linux-block 2015-11-10 17:23:49 -08:00
media various: fix pci_set_dma_mask return value checking 2015-11-20 16:17:32 -08:00
memory ARM: SoC driver updates for v4.4 2015-11-10 15:00:03 -08:00
memstick
message SCSI queue for 4.4. 2015-11-12 07:06:18 -05:00
mfd asm-generic cleanups 2015-11-06 14:22:15 -08:00
misc cxl: Fix possible idr warning when contexts are released 2015-11-24 14:21:27 +11:00
mmc mmc: remove bondage between REQ_META and reliable write 2015-11-09 14:04:52 +01:00
mtd mtd: nand: fix shutdown/reboot for multi-chip systems 2015-11-16 10:51:39 -08:00
net various: fix pci_set_dma_mask return value checking 2015-11-20 16:17:32 -08:00
nfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-11-10 18:11:41 -08:00
ntb NTB: fix 32-bit compiler warning 2015-11-08 16:24:43 -05:00
nubus
nvdimm libnvdimm, pmem: fix size trim in pmem_direct_access() 2015-11-12 09:55:23 -08:00
nvme NVMe: add support for Apple NVMe controller 2015-11-11 09:36:57 -07:00
nvmem
of More power management and ACPI updates for v4.4-rc1 2015-11-12 11:50:33 -08:00
oprofile
parisc pci: remove pci_dma_supported 2015-11-10 16:32:11 -08:00
parport
pci Merge branches 'acpi-smbus', 'acpi-ec' and 'acpi-pci' 2015-11-20 01:22:52 +01:00
pcmcia
perf arm64 updates for 4.4: 2015-11-04 14:47:13 -08:00
phy phy: qcom-ufs: fix build error when the component is built as a module 2015-11-09 17:44:24 -05:00
pinctrl This is the bulk of GPIO changes for v4.4: 2015-11-02 12:59:12 -08:00
platform platform/chrome: Branch for v4.4 2015-11-13 21:53:18 -08:00
pnp
power - New Device Support 2015-11-06 10:23:50 -08:00
powercap
pps
ps3
ptp
pwm pwm: Changes for v4.4-rc1 2015-11-11 09:16:10 -08:00
rapidio
ras
regulator spi: Updates for v4.4 2015-11-05 13:15:12 -08:00
remoteproc
reset
rpmsg
rtc RTC for 4.4 2015-11-10 10:01:21 -08:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2015-11-18 08:59:29 -08:00
sbus
scsi SCSI misc on 20151113 2015-11-13 20:35:54 -08:00
sfi
sh drivers: sh: Get rid of CONFIG_ARCH_SHMOBILE_MULTI 2015-11-17 02:12:46 +09:00
sn
soc ARM: SoC driver updates for v4.4 2015-11-10 15:00:03 -08:00
spi Merge remote-tracking branches 'spi/topic/s3c64xx', 'spi/topic/ti-qspi' and 'spi/topic/txx9' into spi-next 2015-11-04 11:02:16 +00:00
spmi char/misc drivers for 4.4-rc1 2015-11-04 22:15:15 -08:00
ssb ssb: add Kconfig entry for compiling SoC related code 2015-10-28 21:05:21 +02:00
staging Revert "Staging: wilc1000: coreconfigurator: Drop unneeded wrapper functions" 2015-11-18 13:22:44 -08:00
target SCSI misc on 20151113 2015-11-13 20:35:54 -08:00
tc
thermal thermal: rockchip: fix compile error 2015-11-11 19:52:39 -08:00
thunderbolt
tty serial: export fsl8250_handle_irq 2015-11-20 16:19:54 -08:00
uio
usb usblp: do not set TASK_INTERRUPTIBLE before lock 2015-11-19 16:31:42 -08:00
uwb driver core update for 4.4-rc1 2015-11-04 21:50:37 -08:00
vfio VFIO updates for v4.4-rc1 2015-11-13 17:05:32 -08:00
vhost Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2015-11-13 20:04:17 -08:00
video fbdev changes for 4.4 2015-11-10 10:00:09 -08:00
virt
virtio
vlynq
vme char/misc drivers for 4.4-rc1 2015-11-04 22:15:15 -08:00
w1 power supply and reset changes for the v4.4 series 2015-11-05 12:28:15 -08:00
watchdog Merge git://www.linux-watchdog.org/linux-watchdog 2015-11-10 10:11:12 -08:00
xen Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2015-11-13 20:04:17 -08:00
zorro
Kconfig char/misc drivers for 4.4-rc1 2015-11-04 22:15:15 -08:00
Makefile char/misc drivers for 4.4-rc1 2015-11-04 22:15:15 -08:00