linux/drivers/misc/cxl
Vaibhav Jain ea9a26d117 cxl: Force context lock during EEH flow
During an eeh event when the cxl card is fenced and card sysfs attr
perst_reloads_same_image is set following warning message is seen in the
kernel logs:

  Adapter context unlocked with 0 active contexts
  ------------[ cut here ]------------
  WARNING: CPU: 12 PID: 627 at
  ../drivers/misc/cxl/main.c:325 cxl_adapter_context_unlock+0x60/0x80 [cxl]

Even though this warning is harmless, it clutters the kernel log
during an eeh event. This warning is triggered as the EEH callback
cxl_pci_error_detected doesn't obtain a context-lock before forcibly
detaching all active context and when context-lock is released during
call to cxl_configure_adapter from cxl_pci_slot_reset, a warning in
cxl_adapter_context_unlock is triggered.

To fix this warning, we acquire the adapter context-lock via
cxl_adapter_context_lock() in the eeh callback
cxl_pci_error_detected() once all the virtual AFU PHBs are notified
and their contexts detached. The context-lock is released in
cxl_pci_slot_reset() after the adapter is successfully reconfigured
and before the we call the slot_reset callback on slice attached
device-drivers.

Fixes: 70b565bbdb ("cxl: Prevent adapter reset if an active context exists")
Cc: stable@vger.kernel.org # v4.9+
Reported-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Tested-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-02 22:41:41 +10:00
..
api.c cxl: Keep track of mm struct associated with a context 2017-04-13 23:34:29 +10:00
base.c cxl: Add support for interrupts on the Mellanox CX4 2016-07-14 20:27:08 +10:00
context.c cxl: Add psl9 specific code 2017-04-13 23:34:31 +10:00
cxl.h cxl: Add psl9 specific code 2017-04-13 23:34:31 +10:00
debugfs.c cxl: Add psl9 specific code 2017-04-13 23:34:31 +10:00
fault.c cxl: Add psl9 specific code 2017-04-13 23:34:31 +10:00
file.c cxl: Keep track of mm struct associated with a context 2017-04-13 23:34:29 +10:00
flash.c cxl: static-ify variables to fix sparse warnings 2016-06-16 22:49:27 +10:00
guest.c cxl: Add psl9 specific code 2017-04-13 23:34:31 +10:00
hcalls.c cxl: Remove unused values in bare-metal environment. 2017-04-13 23:34:28 +10:00
hcalls.h cxl: Add guest-specific code 2016-03-09 23:36:52 +11:00
irq.c cxl: Add psl9 specific code 2017-04-13 23:34:31 +10:00
Kconfig cxl: remove dead Kconfig options 2016-07-19 20:12:29 +10:00
main.c cxl: Keep track of mm struct associated with a context 2017-04-13 23:34:29 +10:00
Makefile cxl: Fix build when CONFIG_DEBUG_FS=n 2017-02-03 21:59:26 +11:00
native.c cxl: Add psl9 specific code 2017-04-13 23:34:31 +10:00
of.c cxl: replace loop with for_each_child_of_node(), remove unneeded of_node_put() 2016-10-04 16:19:23 +11:00
pci.c cxl: Force context lock during EEH flow 2017-05-02 22:41:41 +10:00
phb.c cxl: Fix error handling in _cxl_pci_associate_default_context() 2016-11-18 22:41:08 +11:00
sysfs.c cxl: Prevent adapter reset if an active context exists 2016-10-19 20:35:39 +11:00
trace.c cxl: Add tracepoints 2015-01-22 17:31:51 +11:00
trace.h cxl: Add psl9 specific code 2017-04-13 23:34:31 +10:00
vphb.c cxl: fix nested locking hang during EEH hotplug 2017-02-21 21:32:52 +11:00