Some power systems do not have legacy ISA devices. So, /dev/port is not
a valid interface on these systems. User level tools such as kbdrate is
trying to access the device using this interface which is causing the
system crash.
This patch will fix this issue by not creating this interface on these
powerpc systems.
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
prom_update_property() currently fails if the property doesn't
actually exist yet which isn't what we want. Change to add-or-update
instead of update-only, then we can remove a lot duplicated lines.
Suggested-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add "memory" attribute in inline assembly language as a compiler
barrier to make sure 4.6.x GCC don't reorder mfmsr().
Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@vger.kernel.org
Just like the module loader, ftrace needs to be updated to use r12
instead of r11 with newer gcc's.
Signed-off-by: Roger Blofeld <blofeldus@yahoo.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@vger.kernel.org
If arch_validate_hwbkpt_settings() fails, bp->ctx won't be valid and the
kernel panics. Add a check to fix this.
Reported-by: Edjunior Barbosa Machado <emachado@linux.vnet.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This allows the linker to know that calls to them do not need to switch
TOC and stop errors like the following when linking large configurations:
powerpc64-linux-ld: drivers/built-in.o: In function `.gpiochip_is_requested':
(.text+0x4): sibling call optimization to `_savegpr0_29' does not allow automatic multiple TOCs; recompile with -mminimal-toc or -fno-optimize-sibling-calls, or make `_savegpr0_29' extern
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We have a request for a fast method of getting CPU and NUMA node IDs
from userspace. This patch implements a getcpu VDSO function,
similar to x86.
Ben suggested we use SPRG3 which is userspace readable. SPRG3 can be
modified by a KVM guest, so we save the SPRG3 value in the paca and
restore it when transitioning from the guest to the host.
I have a glibc patch that implements sched_getcpu on top of this.
Testing on a POWER7:
baseline: 538 cycles
vdso: 30 cycles
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Purely for cosmetic purposes, otherwise it can appear that we are in
single_step_pSeries() which is slightly confusing.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Currently the call to pseries_notify_cpuidle_add_cpu(), that takes
action on the cpuidle front when a cpu is added/removed
is being made from smp_xics_setup_cpu().
This caused lockdep issues as
reported https://lkml.org/lkml/2012/5/17/2
On addition of each cpu,
resources were cleared and re-allocated each time, all in critical
section as part of start_secondary() call were interrupts are disabled.
To resolve this issue, the pseries_notify_cpuidle_add_cpu() call is
is being replaced by a hotplug notifier which
would prevent cpuidle resources from being
released and allocated each time cpu is onlined in the critical code path.
It was fixed in https://lkml.org/lkml/2012/5/18/174.
Also it is essential to call cpuidle_enable/disable_device
between cpuidle_pause_and_lock() and
cpuidle_resume_and_unlock() when used externally
to avoid race conditions. Add support for CPU_ONLINE_FROZEN
and CPU_DEAD_FROZEN as part of hotplug notify event for
pseries_idle and unregister hotplug notifier
while exiting out. The above mentioned issues
are fixed as part of this patch.
Signed-off-by: Deepthi Dharwar <deepthi@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
When I "fixed" the CONFIG_TRACE_IRQFLAGS case on interrupt entry,
I screwed up a little bit with the test for user space vs. kernel.
The code is fine, there's just some dead code around it. I basically
removed the test and always create the added stack frame whether
coming from user or kernel since in any case we do need to save
a bunch of volatile registers or bad things would happen (we can
take page faults in the kernel for example).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Matt added BPF_JIT support in commit 0ca87f05, but currently none of our
defconfigs build it. Turn that sucker on.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Add the ability to inject IOMMU faults. We enable this per device
via a fail_iommu sysfs property, similar to fault injection on other
subsystems.
An example:
...
0003:01:00.1 Ethernet controller: Emulex Corporation OneConnect 10Gb NIC (be3) (rev 02)
To inject one error to this device:
echo 1 > /sys/bus/pci/devices/0003:01:00.1/fail_iommu
echo 1 > /sys/kernel/debug/fail_iommu/probability
echo 1 > /sys/kernel/debug/fail_iommu/times
As feared, the first failure injected on the be3 results in an
unrecoverable error, taking down both functions of the card
permanently:
be2net 0003:01:00.1: Unrecoverable error in the card
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The DMA API debug code has hooks to verify all DMA entries have been
freed at time of hot unplug. We need to call dma_debug_add_bus for
this to work.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Similar to PCI, separate the bus probe from device probe. This allows
us to attach bus notifiers for DMA debug and IOMMU fault injection
before devices have been probed.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
During boot we see a number of these warnings:
vio 30000000: Warning: IOMMU dma not supported: mask 0xffffffffffffffff, table unavailable
The reason for this is that we set IOMMU properties for all VIO
devices even if they are not DMA capable.
Only set DMA ops, table and mask for devices with a DMA window.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We use SIAR or regs->nip for the instruction pointer depending on
the PMU configuration, but we always use regs->nip in the callchain.
Use perf_instruction_pointer so the backtrace is consistent.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
At the moment we always use the SIAR if the PMU supports continuous
sampling. Unfortunately the SIAR and the PMU exception are not
synchronised for non marked events so we can end up with callchains
that dont make sense.
The following patch checks the HV and PR bits for samples coming from
userspace and always uses pt_regs for them. Userspace will never have
interrupts off so there is no real advantage to using the SIAR for
non marked events in userspace.
I had experimented with a patch that did a similar thing for kernel
samples but we lost a significant amount of information. I was
unable to profile any of our early exception code for example.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The logic to choose whether to use the SIAR or get the information
out of pt_regs is going to get more complicated, so do it once in
perf_read_regs.
We overload regs->result which is gross but we are already doing it
with regs->dsisr.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We want to access the MMCRA_SIHV and MMCRA_SIPR bits elsewhere so
create mmcra_sihv and mmcra_sipr which hide the differences between
the old and new layout of the bits.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Some macros use RA where when RA=R0 the values is 0, so make this
the enforced mnemonic in the macro.
Idea suggested by Andreas Schwab.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Enforce the use of R0-R31 in macros where possible now we have all the
fixes in.
R0-R31 macros are removed here so that can't be used anymore. They
should not be defined anywhere.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Now have ___PPC_RA/B/S/T we can use it in some places. These are
places where we can't use the existing defines which will soon enforce
R0-R31 usage.
The macros being changed here are being used in inline asm, which
can't convert to enforce the R0-R31 usage.
bpf_jit uses a mix of both generated and non-generated with the same
code, so just convert all these to use the ___PPC_R versions which
won't enforce R usage later.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
These are currently the same as __PPC_RA/B/S/T but we'll wrap them
soon.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We need to do this so we can enforce the name of a and b in called
macros PPC_RA/B later.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
These macros are using integers where they could be using logical
names since they take registers.
We are going to enforce this soon, so fix these up now.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
LOAD_REG_ADDR define is just a wrapper around real instructions so we
can just use real register names here (ie. lower case).
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
mtocrf define is just a wrapper around the real instructions so we can
just use real register names here (ie. lower case).
Also remove braces in macro so this is possible.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Move this duplicated definition to ppc_asm.h and remove the
braces which prevent the use of %rN register names
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Merge the defines of VCPU_GPR from different places.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Merge the defines of STACKFRAMESIZE, STK_REG, STK_PARAM from different
places.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Now all the fixes are in place, let's rock-n-roll!
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Anything that uses a constructed instruction (ie. from ppc-opcode.h),
need to use the new R0 macro, as %r0 is not going to work.
Also convert usages of macros where we are just determining an offset
(usually for a load/store), like:
std r14,STK_REG(r14)(r1)
Can't use STK_REG(r14) as %r14 doesn't work in the STK_REG macro since
it's just calculating an offset.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
The assembler doesn't take %r0 register arguments in braces, so remove them.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
We are going to use these later and convert r0 to %r0 etc.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
udbg_init_debug_opal() should be udbg_init_debug_opal_raw() as
the caller in arch/powerpc/kernel/udbg.c expects
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Newer gcc are being a bit blind here (it's pretty obvious we don't
reach the code path using the array if we haven't initialized the
pointer) but none of that is performance critical so let's just
silence it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
There was a typo, checking for CONFIG_TRACE_IRQFLAG instead of
CONFIG_TRACE_IRQFLAGS causing some useful debug code to not be
built
This in turns causes a build error on BookE 64-bit due to incorrect
semicolons at the end of a couple of macros, so let's fix that too
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@vger.kernel.org [v3.4]
Looks like we still have issues with pSeries and Cell idle code
vs. the lazy irq state. In fact, the reset fixes that went upstream
are exposing the problem more by causing BUG_ON() to trigger (which
this patch turns into a WARN_ON instead).
We need to be careful when using a variant of low power state that
has the side effect of turning interrupts back on, to properly set
all the SW & lazy state to look as if everything is enabled before
we enter the low power state with MSR:EE off as we will return with
MSR:EE on. If not, we have a discrepancy of state which can cause
things to go very wrong later on.
This patch moves the logic into a helper and uses it from the
pseries and cell idle code. The power4/970 idle code already got
things right (in assembly even !) so I'm not touching it. The power7
"bare metal" idle code is subtly different and correct. Remains PA6T
and some hypervisor based Cell platforms which have questionable
code in there, but they are mostly dead platforms so I'll fix them
when I manage to get final answers from the respective maintainers
about how the low power state actually works on them.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: stable@vger.kernel.org [v3.4]
A smallish fix for a lock dependency issue which affects a bunch of
Qualcomm boards that do unusually complicated things with their
regulators, the API is unlikely to be called by any other system.
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Merge tag 'regulator-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator
Pull regulator fix from Mark Brown:
"A smallish fix for a lock dependency issue which affects a bunch of
Qualcomm boards that do unusually complicated things with their
regulators, the API is unlikely to be called by any other system."
* tag 'regulator-3.5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: Fix recursive mutex lockdep warning
Don't call v4l2_ctrl_g_ctrl on ctrls which the model cam in question
does not have.
Reported-by: Frank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
[ Taken directly, since Mauro is on vacation ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'virtio-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
Pull minor virtio-balloon fix from Rusty Russell:
"Theoretical fix, which greatly simplifies upcoming balloon patches
which will go in via some vm tree."
* tag 'virtio-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
virtio-balloon: fix add/get API use
were reported by Fernando Guzman Lugo.
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Merge tag 'rpmsg-3.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/rpmsg
Pull rpmsg fixes from Ohad Ben-Cohen:
"Fixing two (somewhat rare) endpoint-related race issues, both of which
were reported by Fernando Guzman Lugo."
* tag 'rpmsg-3.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/rpmsg:
rpmsg: make sure inflight messages don't invoke just-removed callbacks
rpmsg: avoid premature deallocation of endpoints
from Shinya Kuribayashi.
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Merge tag 'hwspinlock-3.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/hwspinlock
Pull hwspinlock fix from Ohad Ben-Cohen:
"A single hwspinlock core fix for multiple hwspinlock devices
scenarios, from Shinya Kuribayashi."
* tag 'hwspinlock-3.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad/hwspinlock:
hwspinlock/core: use global ID to register hwspinlocks on multiple devices
Haren Myneni