While checking powersaving mode in machine check handler at 0x200, we
clobber CFAR register. Fix it by saving and restoring it during beq/bgt.
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
I noticed this when testing setarch. No, we don't magically
support a big endian userspace on a little endian kernel.
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The ppc_rtas() syscall allows userspace to interact directly with RTAS.
For the moment, it assumes every thing is big endian and returns either
EINVAL or EFAULT when called in a little endian environment.
As suggested by Benjamin, to avoid bugs when userspace wants to pass
a non 32 bit value to RTAS, it is far better to stick with a simple
rationale: ppc_rtas() should be called with a big endian rtas_args
structure.
With this patch, it is now up to userspace to forge big endian arguments,
as expected by RTAS.
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Our netfilter options are stale and important things like masquerading
are no longer enabled. Instead of trying to keep up with any updates,
set CONFIG_NETFILTER_ADVANCED=n on ppc64* and pseries* defconfigs.
This enables the most common netfilter modules for us.
While here, enable the network bridge module which is heavily used in
KVM setups.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We also set it to be enabled always. This helps in wider testing
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We have generic code like the one in get_futex_key that assume that
a local_irq_disable prevents a parallel THP split. Support that by
adding a dummy smp call function after setting _PAGE_SPLITTING. Code
paths like get_user_pages_fast still need to check for _PAGE_SPLITTING
after disabling IRQ which indicate that a parallel THP splitting is
ongoing. Now if they don't find _PAGE_SPLITTING set, then we can be
sure that parallel split will now block in pmdp_splitting flush
until we enables IRQ
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The facility unavailable exception can be triggered from userspace by
accessing PMU registers when EBB is not enabled. This causes the
included pr_err() to run, hence spamming the kernel log buffer.
This avoids this by rate limiting these messages.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently we reject events which have the L3 bank == 1, such as
0x000084918F, because the cache field is non-zero.
However that is incorrect, because although the bank is non-zero, the
value we would write into MMCRC is zero, and so we can count the event.
So fix the check to ignore the bank selector when checking whether the
cache selector is non-zero.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
gpci and 24x7 expose some device specific attributes. Add some
documentation for them.
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The commit adds a Kconfig option which allows the hv_gpci and hv_24x7
PMUs, added in the preceeding commits, to be built.
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This provides a basic interface between hv_24x7 and perf. Similar to
the one provided for gpci, it lacks transaction support and does not
list any events.
Example usage via perf tool:
perf stat -e 'hv_24x7/domain=2,offset=8,starting_index=0,lpar=0xffffffff/' -r 0 -C 0 -x ' ' sleep 0.1
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This provides a basic link between perf and hv_gpci. Notably, it does
not yet support transactions and does not list any events (they can
still be manually composed).
Example usage via perf tool:
perf stat -e 'hv_gpci/counter_info_version=3,offset=0,length=8,secondary_index=0,starting_index=0xffffffff,request=0x10/' -r 0 -C 0 -x ' ' sleep 0.1
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add two macros which generate functions to extract the relevent bits
from event->attr.config{,1,2}.
EVENT_DEFINE_RANGE() defines an accessor for a range of bits in the
event, as well as a "max" function that gives the maximum value of the
field based on the bit width.
EVENT_DEFINE_RANGE_FORMAT() defines the accessor & max routine and also
a format attribute for use in the PMU's attr_groups.
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
[mpe: move to powerpc, ugly but descriptive macro names]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This exposes a simple way to grab the firmware provided
collect_priveliged, ga, expanded, and lab capability bits. All of these
bits come in from the same gpci request, so we've exposed all of them.
Only the collect_priveliged bit is really used by the hv-gpci/hv-24x7
code, the other bits are simply exposed in sysfs to inform the user.
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
24x7 (also called hv_24x7 or H_24X7) is an interface to obtain
performance counters from the hypervisor. These counters do not have a
fixed format/possition and are instead documented in a "24x7 Catalog",
which is provided by the hypervisor (that interface is also documented
paritialy in the included hv-24x7-catalog.h and fully in at
https://raw.githubusercontent.com/jmesmon/catalog-24x7/master/hv-24x7-catalog.h ).
The 24x7 data access is simply a copy operation into a 4 dimentional
array of 64bit counters (from hypervisor to kernel memory). There is no
interupt triggered on overflow, these are completely disjoint from the
typical power pmu.
This method of obtaining performance counters from the hypervisor is
intended to paritialy replace the gpci interface.
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
"H_GetPerformanceCounterInfo" (refered to as hv_gpci or just gpci from
here on) is an interface to retrieve specific performance counters and
other data from the hypervisor. All outputs have a fixed format. This
header only describes the portions of the interface that we plan on
using in linux at this time.
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
bin_attributes created/updated in create_files() (such as those listed
via (struct device).attribute_groups) were not placed under the
specified group, and instead appeared in the base kobj directory.
Fix this by making bin_attributes use creating code similar to normal
attributes.
A quick grep shows that no one is using bin_attrs in a named attribute
group yet, so we can do this without breaking anything in usespace.
Note that I do not add is_visible() support to
bin_attributes, though that could be done as well.
This is a copy of the patch already merged in Greg's tree.
Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The previous commit added constraint and register handling to allow
processes using EBB (Event Based Branches) to request access to the BHRB
(Branch History Rolling Buffer).
With that in place we can allow processes using EBB to access the BHRB.
This is achieved by setting BHRBA in MMCR0 when we enable EBB access. We
must also clear BHRBA when we are disabling.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We want a way for users of EBB (Event Based Branches) to also access the
BHRB (Branch History Rolling Buffer). EBB does not interoperate with our
existing BHRB support, which is wired into the generic Linux branch
stack sampling support.
To support EBB & BHRB we add three new bits to the event code. The first
bit indicates that the event wants access to the BHRB, and the other two
bits indicate the desired IFM (Instruction Filtering Mode).
We allow multiple events to request access to the BHRB, but they must
agree on the IFM value. Events which are not interested in the BHRB can
also interoperate with events which do.
Finally we program the desired IFM value into MMCRA. Although we do this
for every event, we know that the value will be identical for all events
that request BHRB access.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We only need to mask the EBB bit out of the event for the check of the
special PMC 5 & 6 events. So use a local to do it just for that code,
rather than changing the event value for the life of the function.
While we're there move the set of mask and value after all the checks.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Rather than using PERF_EVENT_CONFIG_EBB_SHIFT everywhere, add an
EVENT_EBB_SHIFT like every other event and use that.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Although we already block EBB events which request sampling using
sample_period, technically it's possible for an event to set sample_type
but not sample_period.
Nothing terrible will happen if an EBB event does specify sample_type,
but it signals a major confusion on the part of userspace, and so we do
them the favor of rejecting it.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Some power8 revisions have a hardware bug where we can lose a PMU
exception, this commit adds a workaround to detect the bad condition and
rectify the situation.
See the comment in the commit for a full description.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Some power8 revisions have a hardware bug where we can lose a
Performance Monitor (PMU) exception under certain circumstances.
We will be adding a workaround for this case, see the next commit for
details. The observed behaviour is that writing PMAO doesn't cause an
exception as we would expect, hence the name of the feature.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently the sysrq ShowRegs command does not print any PMU registers as
we have an empty definition for perf_event_print_debug(). This patch
defines perf_event_print_debug() to print various PMU registers.
Example output:
CPU: 0 PMU registers, ppmu = POWER7 n_counters = 6
PMC1: 00000000 PMC2: 00000000 PMC3: 00000000 PMC4: 00000000
PMC5: 00000000 PMC6: 00000000 PMC7: deadbeef PMC8: deadbeef
MMCR0: 0000000080000000 MMCR1: 0000000000000000 MMCRA: 0f00000001000000
SIAR: 0000000000000000 SDAR: 0000000000000000 SIER: 0000000000000000
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
[mpe: Fix 32 bit build and rework formatting for compactness]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patchset adds some missing event list for POWER7 PMU raw
events which are exported through sysfs interface. Also updates
the ABI documentation to add all the sysfs exported raw events.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Alistair Popple has volunteered to take over maintainership of the ppc4xx
stuff upstream. Switch the MAINTAINERS entry over to him.
Signed-off-by: Josh Boyer <jwboyer@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch adds basic kernel enablement for reading power values, fan
speed rpm and temperature values on powernv platforms which will
be exported to user space through sysfs interface.
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.vnet.ibm.com>
Signed-off-by: Neelesh Gupta <neelegup@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch enables fetching of various platform sensor data through
OPAL and expects a sensor handle from the driver to pass to OPAL.
Signed-off-by: Neelesh Gupta <neelegup@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch enables reading and updating of system parameters through
OPAL call.
Signed-off-by: Neelesh Gupta <neelegup@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch adds support for notifying the clients of their request
completion. Clients request for the token before making OPAL call
and then wait for the response.
This patch uses messaging infrastructure to pull the data to linux
by registering itself for the message type OPAL_MSG_ASYNC_COMP.
Signed-off-by: Neelesh Gupta <neelegup@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Now that the arch_{spin,read,write}_relax macros default to cpu_relax(),
remove the redundant definitions for parisc.
Cc: Helge Deller <deller@gmx.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Helge Deller <deller@gmx.de>
We seem to be nearly the only platform which does not provide the
sys_utimes syscall. Adding it now makes our life much easier with
userspace applications (like dietlibc and e2fsprogs) since we then
behave like all other platforms too and don't need extra patches which
are hard to get upstream anyway because we are not a mainstream
architecture.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v3.13
The attached change removes the unused and experimental
CONFIG_PARISC_TMPALIAS code. It doesn't work and I don't believe it will
ever be used.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
STI console is used on parisc and m68k HP machines. This patch partly reverts
my previous commit and as such restores the fonts for the m68k machines.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # v3.13
This is mostly a few additional fixes from Lars-Peter, a new driver and
cleaning up a git failure with merging the Intel branch (combined with
an xargs failure to pay attention to error codes). The history lists a
bunch of additional commits for the branch but the content of those
commits is actually present already but not recorded in history due to
git failing. Unfortunately xargs is used in the merge script and it
doesn't do a good job of noticing errors from the commands it invokes.
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Merge tag 'asoc-v3.15-2' into asoc-next
ASoC: Updates for v3.15
This is mostly a few additional fixes from Lars-Peter, a new driver and
cleaning up a git failure with merging the Intel branch (combined with
an xargs failure to pay attention to error codes). The history lists a
bunch of additional commits for the branch but the content of those
commits is actually present already but not recorded in history due to
git failing. Unfortunately xargs is used in the merge script and it
doesn't do a good job of noticing errors from the commands it invokes.
# gpg: Signature made Thu 13 Mar 2014 14:25:44 GMT using RSA key ID 7EA229BD
# gpg: Good signature from "Mark Brown <broonie@sirena.org.uk>"
# gpg: aka "Mark Brown <broonie@debian.org>"
# gpg: aka "Mark Brown <broonie@kernel.org>"
# gpg: aka "Mark Brown <broonie@tardis.ed.ac.uk>"
# gpg: aka "Mark Brown <broonie@linaro.org>"
# gpg: aka "Mark Brown <Mark.Brown@linaro.org>"
Quite a busy release for ASoC this time, more on janitorial work than
exciting new features but welcome nontheless:
- Lots of cleanups from Takashi for enumerations; the original API for
these was error prone so he's refactored lots of code to use more
modern APIs which avoid issues.
- Elimination of the ASoC level wrappers for I2C and SPI moving us
closer to converting to regmap completely and avoiding some
randconfig hassle.
- Provide both manually and transparently locked DAPM APIs rather than
a mix of the two fixing some concurrency issues.
- Start converting CODEC drivers to use separate bus interface drivers
rather than having them all in one file helping avoid dependency
issues.
- DPCM support for Intel Haswell and Bay Trail platforms.
- Lots of work on improvements for simple-card, DaVinci and the Renesas
rcar drivers.
- New drivers for Analog Devices ADAU1977, TI PCM512x and parts of the
CSR SiRF SoC.
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Merge tag 'asoc-v3.15' into asoc-next
ASoC: Updates for v3.15
Quite a busy release for ASoC this time, more on janitorial work than
exciting new features but welcome nontheless:
- Lots of cleanups from Takashi for enumerations; the original API for
these was error prone so he's refactored lots of code to use more
modern APIs which avoid issues.
- Elimination of the ASoC level wrappers for I2C and SPI moving us
closer to converting to regmap completely and avoiding some
randconfig hassle.
- Provide both manually and transparently locked DAPM APIs rather than
a mix of the two fixing some concurrency issues.
- Start converting CODEC drivers to use separate bus interface drivers
rather than having them all in one file helping avoid dependency
issues.
- DPCM support for Intel Haswell and Bay Trail platforms.
- Lots of work on improvements for simple-card, DaVinci and the Renesas
rcar drivers.
- New drivers for Analog Devices ADAU1977, TI PCM512x and parts of the
CSR SiRF SoC.
# gpg: Signature made Wed 12 Mar 2014 23:05:45 GMT using RSA key ID 7EA229BD
# gpg: Good signature from "Mark Brown <broonie@sirena.org.uk>"
# gpg: aka "Mark Brown <broonie@debian.org>"
# gpg: aka "Mark Brown <broonie@kernel.org>"
# gpg: aka "Mark Brown <broonie@tardis.ed.ac.uk>"
# gpg: aka "Mark Brown <broonie@linaro.org>"
# gpg: aka "Mark Brown <Mark.Brown@linaro.org>"
The changes in "ASoC: pcm: free path list before exiting from error
conditions" actually introduced both double frees (in case where the
path list was allocated but empty) and frees of unallocated memory (in
cases where the error being handled was -ENOMEM. Drop the commit for
now.
Fixes: e4ad1accb (ASoC: pcm: free path list before exiting from error conditions)
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Mark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org
We can get false negative from __lookup_mnt() if an unrelated vfsmount
gets moved. In that case legitimize_mnt() is guaranteed to fail,
and we will fall back to non-RCU walk... unless we end up running
into a hard error on a filesystem object we wouldn't have reached
if not for that false negative. IOW, delaying that check until
the end of pathname resolution is wrong - we should recheck right
after we attempt to cross the mountpoint. We don't need to recheck
unless we see d_mountpoint() being true - in that case even if
we have just raced with mount/umount, we can simply go on as if
we'd come at the moment when the sucker wasn't a mountpoint; if we
run into a hard error as the result, it was a legitimate outcome.
__lookup_mnt() returning NULL is different in that respect, since
it might've happened due to operation on completely unrelated
mountpoint.
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In all callchains leading to prepend_name(), the value left in *buflen
is eventually discarded unused if prepend_name() has returned a negative.
So we are free to do what prepend() does, and subtract from *buflen
*before* checking for underflow (which turns into checking the sign
of subtraction result, of course).
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
