When machine check real mode handler can not continue into host kernel
in V mode, it returns from the interrupt and we loose MCE event which
never gets logged. In such a situation queue up the MCE event so that
we can log it later when we get back into host kernel with r1 pointing to
kernel stack e.g. during syscall exit.
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Now that we handle machine check in linux, the MCE decoding should also
take place in linux host. This info is crucial to log before we go down
in case we can not handle the machine check errors. This patch decodes
and populates a machine check event which contain high level meaning full
MCE information.
We do this in real mode C code with ME bit on. The MCE information is still
available on emergency stack (in pt_regs structure format). Even if we take
another exception at this point the MCE early handler will allocate a new
stack frame on top of current one. So when we return back here we still have
our MCE information safe on current stack.
We use per cpu buffer to save high level MCE information. Each per cpu buffer
is an array of machine check event structure indexed by per cpu counter
mce_nest_count. The mce_nest_count is incremented every time we enter
machine check early handler in real mode to get the current free slot
(index = mce_nest_count - 1). The mce_nest_count is decremented once the
MCE info is consumed by virtual mode machine exception handler.
This patch provides save_mce_event(), get_mce_event() and release_mce_event()
generic routines that can be used by machine check handlers to populate and
retrieve the event. The routine release_mce_event() will free the event slot so
that it can be reused. Caller can invoke get_mce_event() with a release flag
either to release the event slot immediately OR keep it so that it can be
fetched again. The event slot can be also released anytime by invoking
release_mce_event().
This patch also updates kvm code to invoke get_mce_event to retrieve generic
mce event rather than paca->opal_mce_evt.
The KVM code always calls get_mce_event() with release flags set to false so
that event is available for linus host machine
If machine check occurs while we are in guest, KVM tries to handle the error.
If KVM is able to handle MC error successfully, it enters the guest and
delivers the machine check to guest. If KVM is not able to handle MC error, it
exists the guest and passes the control to linux host machine check handler
which then logs MC event and decides how to handle it in linux host. In failure
case, KVM needs to make sure that the MC event is available for linux host to
consume. Hence KVM always calls get_mce_event() with release flags set to false
and later it invokes release_mce_event() only if it succeeds to handle error.
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
usual for this cycle with lots of clean-up.
- Cross arch clean-up and consolidation of early DT scanning code.
- Clean-up and removal of arch prom.h headers. Makes arch specific
prom.h optional on all but Sparc.
- Addition of interrupts-extended property for devices connected to
multiple interrupt controllers.
- Refactoring of DT interrupt parsing code in preparation for deferred
probe of interrupts.
- ARM cpu and cpu topology bindings documentation.
- Various DT vendor binding documentation updates.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)
iQEcBAABAgAGBQJSgPQ4AAoJEMhvYp4jgsXif28H/1WkrXq5+lCFQZF8nbYdE2h0
R8PsfiJJmAl6/wFgQTsRel+ScMk2hiP08uTyqf2RLnB1v87gCF7MKVaLOdONfUDi
huXbcQGWCmZv0tbBIklxJe3+X3FIJch4gnyUvPudD1m8a0R0LxWXH/NhdTSFyB20
PNjhN/IzoN40X1PSAhfB5ndWnoxXBoehV/IVHVDU42vkPVbVTyGAw5qJzHW8CLyN
2oGTOalOO4ffQ7dIkBEQfj0mrgGcODToPdDvUQyyGZjYK2FY2sGrjyquir6SDcNa
Q4gwatHTu0ygXpyphjtQf5tc3ZCejJ/F0s3olOAS1ahKGfe01fehtwPRROQnCK8=
=GCbY
-----END PGP SIGNATURE-----
Merge tag 'devicetree-for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull devicetree updates from Rob Herring:
"DeviceTree updates for 3.13. This is a bit larger pull request than
usual for this cycle with lots of clean-up.
- Cross arch clean-up and consolidation of early DT scanning code.
- Clean-up and removal of arch prom.h headers. Makes arch specific
prom.h optional on all but Sparc.
- Addition of interrupts-extended property for devices connected to
multiple interrupt controllers.
- Refactoring of DT interrupt parsing code in preparation for
deferred probe of interrupts.
- ARM cpu and cpu topology bindings documentation.
- Various DT vendor binding documentation updates"
* tag 'devicetree-for-3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (82 commits)
powerpc: add missing explicit OF includes for ppc
dt/irq: add empty of_irq_count for !OF_IRQ
dt: disable self-tests for !OF_IRQ
of: irq: Fix interrupt-map entry matching
MIPS: Netlogic: replace early_init_devtree() call
of: Add Panasonic Corporation vendor prefix
of: Add Chunghwa Picture Tubes Ltd. vendor prefix
of: Add AU Optronics Corporation vendor prefix
of/irq: Fix potential buffer overflow
of/irq: Fix bug in interrupt parsing refactor.
of: set dma_mask to point to coherent_dma_mask
of: add vendor prefix for PHYTEC Messtechnik GmbH
DT: sort vendor-prefixes.txt
of: Add vendor prefix for Cadence
of: Add empty for_each_available_child_of_node() macro definition
arm/versatile: Fix versatile irq specifications.
of/irq: create interrupts-extended property
microblaze/pci: Drop PowerPC-ism from irq parsing
of/irq: Create of_irq_parse_and_map_pci() to consolidate arch code.
of/irq: Use irq_of_parse_and_map()
...
Code update interface for powernv platform. This provides
sysfs interface to pass new image, validate, update and
commit images.
This patch includes:
- Below OPAL APIs for code update
- opal_validate_flash()
- opal_manage_flash()
- opal_update_flash()
- Create below sysfs files under /sys/firmware/opal
- image : Interface to pass new FW image
- validate_flash : Validate candidate image
- manage_flash : Commit/Reject operations
- update_flash : Flash new candidate image
Updating Image:
"update_flash" is an interface to indicate flash new FW.
It just passes image SG list to FW. Actual flashing is done
during system reboot time.
Note:
- SG entry format:
I have kept version number to keep this list similar to what
PAPR is defined.
Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Create /sys/firmware/opal directory. We wil use this
interface to fetch opal error logs, firmware update, etc.
Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
pnv_pci_setup_bml_iommu was missing a byteswap of a device
tree property.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The powernv exception handlers are not ready to take exceptions
in little endian mode, so disable them.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When removing prom.h include by of.h, several OF headers will no longer
be implicitly included. Add explicit includes of of_*.h as needed.
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Grant Likely <grant.likely@linaro.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: linuxppc-dev@lists.ozlabs.org
Some machines might provide the console via a different mechanism
such as direct access to a UART from Linux, in which case OPAL
might not expose any console. In that case, the code would cause
a NULL dereference.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Address some of the trivial sparse warnings in arch/powerpc.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch implements a notifier to receive a notification on OPAL
event mask changes. The notifier is only called as a result of an OPAL
interrupt, which will happen upon reception of FSP messages or PCI errors.
Any event mask change detected as a result of opal_poll_events() will not
result in a notifier call.
[benh: changelog]
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We add a machine_shutdown hook that frees the OPAL interrupts
(so they get masked at the source and don't fire while kexec'ing)
and which triggers an IODA reset on all the PCIe host bridges
which will have the effect of blocking all DMAs and subsequent
PCIs interrupts.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
If the firmware returns an error such as "closed" (or hardware
error), we should drop characters.
Currently we only do that when a firmware compatible with OPAL v2
APIs is detected, in the code that calls opal_console_write_buffer_space(),
which didn't exist with OPAL v1 (or didn't work).
However, when enabling early debug consoles, the flag indicating
that v2 is supported isn't set yet, causing us, in case of errors
or closed console, to spin forever.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently, the OPAL exception vectors are registered before the feature
fixups are processed. This means that the now-firmware-owned vectors
will likely be overwritten by the kernel.
This change moves the exception registration code to an early initcall,
rather than at machine_init time.
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
OPAL can handle various interrupt for us such as Machine Checks (it
performs all sorts of recovery tasks and passes back control to us with
informations about the error), Hardware Management Interrupts and Softpatch
interrupts.
This wires up the mechanisms and prints out specific informations returned
by HAL when a machine check occurs.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We do the minimum which is to "pass" interrupts to HAL, which
makes the console smoother and will allow us to implement
interrupt based completion and console.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This adds a udbg and an hvc console backend for supporting a console
using the OPAL console interfaces.
On OPAL v1 we have hvc0 mapped to whatever console the system was
configured for (network or hvsi serial port) via the service
processor.
On OPAL v2 we have hvcN mapped to the Nth console provided by OPAL
which generally corresponds to:
hvc0 : network console (raw protocol)
hvc1 : serial port S1 (hvsi)
hvc2 : serial port S2 (hvsi)
Note: At this point, early debug console only works with OPAL v1
and shouldn't be enabled in a normal kernel.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add definition of OPAL interfaces along with the wrappers to call
into OPAL runtime and the early device-tree parsing hook to locate
the OPAL runtime firmware.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>