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Include instruction opcodes for divde and divdeu as macros.
Signed-off-by: Balamuruhan S <[email protected]>
Reviewed-by: Sandipan Das <[email protected]>
Acked-by: Naveen N. Rao <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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'arm/exynos', 'arm/smmu', 'ppc/pamu', 'x86/vt-d', 'x86/amd' and 'core' into next
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This adds a kernel command line option that can be used to disable GTSE support.
Disabling GTSE implies kernel will make hcalls to invalidate TLB entries.
This was done so that we can do VM migration between configs that enable/disable
GTSE support via hypervisor. To migrate a VM from a system that supports
GTSE to a system that doesn't, we can boot the guest with
radix_hcall_invalidate=on, thereby forcing the guest to use hcalls for TLB
invalidates.
The check for hcall availability is done in pSeries_setup_arch so that
the panic message appears on the console. This should only happen on
a hypervisor that doesn't force the guest to hash translation even
though it can't handle the radix GTSE=0 request via CAS. With
radix_hcall_invalidate=on if the hypervisor doesn't support hcall_rpt_invalidate
hcall it should force the LPAR to hash translation.
Signed-off-by: Aneesh Kumar K.V <[email protected]>
Tested-by: Bharata B Rao <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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commit: cf11e85fc08c ("mm: hugetlb: optionally allocate gigantic hugepages using cma")
added support for allocating gigantic hugepages using CMA. This patch
enables the same for powerpc
Signed-off-by: Aneesh Kumar K.V <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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There's a comment in time.h referring to CONFIG_POWER, which doesn't
exist. That confuses scripts/checkkconfigsymbols.py.
Presumably the comment was referring to a CONFIG_POWER vs CONFIG_PPC,
in which case for CONFIG_POWER we would #define __USE_RTC to 1. But
instead we have CONFIG_PPC_BOOK3S_601, and these days we have
IS_ENABLED().
So the comment is no longer relevant, drop it.
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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We have two uses of CONFIG_BOOK3S_601, which doesn't exist. Fix them
to use CONFIG_PPC_BOOK3S_601 which is the correct symbol.
Fixes: 12c3f1fd87bf ("powerpc/32s: get rid of CPU_FTR_601 feature")
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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This code was merged 11 years ago in commit 13363ab9b9d0 ("powerpc:
Add definitions used by exception handling on 64-bit Book3E") but was
never able to be built because CONFIG_BOOK3E_MMU_TLB_STATS never
existed. Remove it.
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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During memory hotplug and unplug, resize_hpt_for_hotplug() gets called
for both hash and radix guests but it should be called only for hash
guests. Though the call does nothing in the radix guest case, it is
cleaner to push this call into hash specific memory hotplug routines.
Reported-by: Nathan Lynch <[email protected]>
Signed-off-by: Bharata B Rao <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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KVM guests have certain restrictions and performance quirks when using
doorbells. This patch moves the EPAPR KVM guest test so it can be shared
with PSERIES, and uses that in doorbell setup code to apply the KVM
guest quirks and improves IPI performance for two cases:
- PowerVM guests may now use doorbells even if they are secure.
- KVM guests no longer use doorbells if XIVE is available.
There is a valid complaint that "KVM guest" is not a very reasonable
thing to test for, it's preferable for the hypervisor to advertise
particular behaviours to the guest so they could change if the
hypervisor implementation or configuration changes. However in this case
we were already assuming a KVM guest worst case, so this patch is about
containing those quirks. If KVM later advertises fast doorbells, we
should test for that and override the quirks.
Signed-off-by: Nicholas Piggin <[email protected]>
Tested-by: Cédric Le Goater <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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These are only called in one place for a given platform, so inline
them for performance.
Signed-off-by: Nicholas Piggin <[email protected]>
Tested-by: Cédric Le Goater <[email protected]>
[mpe: Fix build errors related to KVM]
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Commit 9908c826d5ed ("powerpc/perf: Add Power10 PMU feature to DT CPU
features") defines MMCRA_BHRB_DISABLE as `0x2000000000UL`. Binutils
version less than 2.28 doesn't support UL suffix.
arch/powerpc/kernel/cpu_setup_power.S: Assembler messages:
arch/powerpc/kernel/cpu_setup_power.S:250: Error: found 'L', expected: ')'
arch/powerpc/kernel/cpu_setup_power.S:250: Error: junk at end of line, first unrecognized character is `L'
arch/powerpc/kernel/cpu_setup_power.S:250: Error: found 'L', expected: ')'
arch/powerpc/kernel/cpu_setup_power.S:250: Error: found 'L', expected: ')'
arch/powerpc/kernel/cpu_setup_power.S:250: Error: junk at end of line, first unrecognized character is `L'
arch/powerpc/kernel/cpu_setup_power.S:250: Error: found 'L', expected: ')'
arch/powerpc/kernel/cpu_setup_power.S:250: Error: found 'L', expected: ')'
arch/powerpc/kernel/cpu_setup_power.S:250: Error: operand out of range (0x0000002000000000 is not between 0xffffffffffff8000 and 0x000000000000ffff)
Fix this by wrapping it with the `_UL` macro.
Fixes: 9908c826d5ed ("Add Power10 PMU feature to DT CPU features")
Suggested-by: Michael Ellerman <[email protected]>
Signed-off-by: Athira Rajeev <[email protected]>
Reviewed-by: Madhavan Srinivasan <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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When a memory slot is hot plugged to a SVM, PFNs associated with the
GFNs in that slot must be migrated to the secure-PFNs, aka device-PFNs.
Call kvmppc_uv_migrate_mem_slot() to accomplish this.
Disable page-merge for all pages in the memory slot.
Reviewed-by: Bharata B Rao <[email protected]>
Signed-off-by: Ram Pai <[email protected]>
[rearranged the code, and modified the commit log]
Signed-off-by: Laurent Dufour <[email protected]>
Signed-off-by: Paul Mackerras <[email protected]>
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all uses are conditional upon ELF_CORE_COPY_XFPREGS, which has not
been defined on any architecture since 2010
Signed-off-by: Al Viro <[email protected]>
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Drop the repeated word "the".
Signed-off-by: Randy Dunlap <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Drop the repeated word "a".
Signed-off-by: Randy Dunlap <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Drop the repeated word "in".
Signed-off-by: Randy Dunlap <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Drop the repeated word "the".
Signed-off-by: Randy Dunlap <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Drop the repeated words "file" and "the".
Signed-off-by: Randy Dunlap <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Drop the repeated word "use".
Signed-off-by: Randy Dunlap <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Drop the repeated word "per".
Signed-off-by: Randy Dunlap <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Drop the repeated word "below".
Signed-off-by: Randy Dunlap <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Align it with other architectures and none of the callers has
been interested its return
Signed-off-by: Li RongQing <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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When STRICT_KERNEL_RWX is set, we want to set NX bit on vmalloc
segments. But modules require exec.
Use a dedicated segment for modules. There is not much space
above kernel, and we don't waste vmalloc space to do alignment.
Therefore, we take the segment before PAGE_OFFSET for modules.
Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/eb8faba9148b6cf17c696ba776b4e8ee2f6313bf.1593428200.git.christophe.leroy@csgroup.eu
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User space stops at TASK_SIZE. At the moment, kernel space starts
at PAGE_OFFSET.
In order to use space between TASK_SIZE and PAGE_OFFSET for modules,
make TASK_SIZE the limit between user and kernel space.
Note that fault.c already considers TASK_SIZE as the boundary between
user and kernel space.
Signed-off-by: Christophe Leroy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/b38b52cd8dabbb56fbd6f9219d6f3cdccbb43b44.1593428200.git.christophe.leroy@csgroup.eu
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This implements smp_cond_load_relaxed() with the slowpath busy loop
using the preferred SMT priority pattern.
Signed-off-by: Nicholas Piggin <[email protected]>
Acked-by: Waiman Long <[email protected]>
[mpe: Make it 64-bit only to fix build errors on 32-bit]
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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This brings the behaviour of the uncontended fast path back to roughly
equivalent to simple spinlocks -- a single atomic op with lock hint.
Signed-off-by: Nicholas Piggin <[email protected]>
Acked-by: Waiman Long <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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This implements the generic paravirt qspinlocks using H_PROD and
H_CONFER to kick and wait.
This uses an un-directed yield to any CPU rather than the directed
yield to a pre-empted lock holder that paravirtualised simple
spinlocks use, that requires no kick hcall. This is something that
could be investigated and improved in future.
Performance results can be found in the commit which added queued
spinlocks.
Signed-off-by: Nicholas Piggin <[email protected]>
Acked-by: Peter Zijlstra (Intel) <[email protected]>
Acked-by: Waiman Long <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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These have shown significantly improved performance and fairness when
spinlock contention is moderate to high on very large systems.
With this series including subsequent patches, on a 16 socket 1536
thread POWER9, a stress test such as same-file open/close from all
CPUs gets big speedups, 11620op/s aggregate with simple spinlocks vs
384158op/s (33x faster), where the difference in throughput between
the fastest and slowest thread goes from 7x to 1.4x.
Thanks to the fast path being identical in terms of atomics and
barriers (after a subsequent optimisation patch), single threaded
performance is not changed (no measurable difference).
On smaller systems, performance and fairness seems to be generally
improved. Using dbench on tmpfs as a test (that starts to run into
kernel spinlock contention), a 2-socket OpenPOWER POWER9 system was
tested with bare metal and KVM guest configurations. Results can be
found here:
https://github.com/linuxppc/issues/issues/305#issuecomment-663487453
Observations are:
- Queued spinlocks are equal when contention is insignificant, as
expected and as measured with microbenchmarks.
- When there is contention, on bare metal queued spinlocks have better
throughput and max latency at all points.
- When virtualised, queued spinlocks are slightly worse approaching
peak throughput, but significantly better throughput and max latency
at all points beyond peak, until queued spinlock maximum latency
rises when clients are 2x vCPUs.
The regressions haven't been analysed very well yet, there are a lot
of things that can be tuned, particularly the paravirtualised locking,
but the numbers already look like a good net win even on relatively
small systems.
Signed-off-by: Nicholas Piggin <[email protected]>
Acked-by: Peter Zijlstra (Intel) <[email protected]>
Acked-by: Waiman Long <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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To prepare for queued spinlocks. This is a simple rename except to
update preprocessor guard name and a file reference.
Signed-off-by: Nicholas Piggin <[email protected]>
Acked-by: Waiman Long <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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These functions will be used by the queued spinlock implementation,
and may be useful elsewhere too, so move them out of spinlock.h.
Signed-off-by: Nicholas Piggin <[email protected]>
Acked-by: Waiman Long <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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pci-ioda.c is getting a bit unwieldly due to the amount of stuff jammed in
there. The SR-IOV support can be extracted easily enough and is mostly
standalone, so move it into a separate file.
This patch also moves the PowerNV SR-IOV specific fields from pci_dn and
moves them into a platform specific structure. I'm not sure how they ended
up in there in the first place, but leaking platform specifics into common
code has proven to be a terrible idea so far so lets stop doing that.
Signed-off-by: Oliver O'Halloran <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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The EEH core has a concept of a "PE tree" to support PowerNV. The PE tree
follows the PCI bus structures because a reset asserted on an upstream
bridge will be propagated to the downstream bridges. On pseries there's a
1-1 correspondence between what the guest sees are a PHB and a PE so the
"tree" is really just a single node.
Current the EEH core is reponsible for setting up this PE tree which it
does by traversing the pci_dn tree. The structure of the pci_dn tree
matches the bus tree on PowerNV which leads to the PE tree being "correct"
this setup method doesn't make a whole lot of sense and it's actively
confusing for the pseries case where it doesn't really do anything.
We want to remove the dependence on pci_dn anyway so this patch move
choosing where to insert a new PE into the platform code rather than
being part of the generic EEH code. For PowerNV this simplifies the
tree building logic and removes the use of pci_dn. For pseries we
keep the existing logic. I'm not really convinced it does anything
due to the 1-1 PE-to-PHB correspondence so every device under that
PHB should be in the same PE, but I'd rather not remove it entirely
until we've had a chance to look at it more deeply.
Signed-off-by: Oliver O'Halloran <[email protected]>
Reviewed-by: Alexey Kardashevskiy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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The naming of eeh_{add_to|remove_from}_parent_pe() doesn't really reflect
what they actually do. If the PE referred to be edev->pe_config_addr
already exists under that PHB then the edev is added to that PE. However,
if the PE doesn't exist the a new one is created for the edev.
The bulk of the implementation of eeh_add_to_parent_pe() covers that
second case. Similarly, most of eeh_remove_from_parent_pe() is
determining when it's safe to delete a PE.
Signed-off-by: Oliver O'Halloran <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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The edev->class_code field is never referenced anywhere except for the
platform specific probe functions. The same information is available in
the pci_dev for PowerNV and in the pci_dn on pseries so we can remove
the field.
Signed-off-by: Oliver O'Halloran <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Mechanical conversion of the eeh_ops interfaces to use eeh_dev to reference
a specific device rather than pci_dn. No functional changes.
Signed-off-by: Oliver O'Halloran <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Mechanical conversion of the eeh_ops interfaces to use eeh_dev to reference
a specific device rather than pci_dn. No functional changes.
Signed-off-by: Oliver O'Halloran <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Mechanical conversion of the eeh_ops interfaces to use eeh_dev to reference
a specific device rather than pci_dn. No functional changes.
Signed-off-by: Oliver O'Halloran <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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There's a bunch of strange things about this code. First up is that none of
the fields being written to are functional for a VF. The SR-IOV
specification lists then as "Reserved, but OS should preserve" so writing
new values to them doesn't do anything and is clearly wrong from a
correctness perspective.
However, since VFs are designed to be managed by the OS there is an
argument to be made that we should be saving and restoring some parts of
config space. We already sort of do that by saving the first 64 bytes of
config space in the eeh_dev (see eeh_dev->config_space[]). This is
inadequate since it doesn't even consider saving and restoring the PCI
capability structures. However, this is a problem with EEH in general and
that needs to be fixed for non-VF devices too.
There's no real reason to keep around this around so delete it.
Signed-off-by: Oliver O'Halloran <[email protected]>
Reviewed-by: Alexey Kardashevskiy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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This is used in precisely one place which is in pseries specific platform
code. There's no need to have the callback in eeh_ops since the platform
chooses the EEH PE addresses anyway. The PowerNV implementation has always
been a stub too so remove it.
Signed-off-by: Oliver O'Halloran <[email protected]>
Reviewed-by: Alexey Kardashevskiy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Drivers that do not support the PCI error handling callbacks are handled by
tearing down the device and re-probing them. If the device being removed is
a virtual function then we need to know the VF index so it can be removed
using the pci_iov_{add|remove}_virtfn() API.
Currently this is handled by looking up the pci_dn, and using the vf_index
that was stashed there when the pci_dn for the VF was created in
pcibios_sriov_enable(). We would like to eliminate the use of pci_dn
outside of pseries though so we need to provide the generic EEH code with
some other way to find the vf_index.
The easiest thing to do here is move the vf_index field out of pci_dn and
into eeh_dev. Currently pci_dn and eeh_dev are allocated and initialized
together so this is a fairly minimal change in preparation for splitting
pci_dn and eeh_dev in the future.
Signed-off-by: Oliver O'Halloran <[email protected]>
Reviewed-by: Alexey Kardashevskiy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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The only thing in this file is eeh_dev_init() which is allocates and
initialises an eeh_dev based on a pci_dn. This is only ever called from
pci_dn.c so move it into there and remove the file.
Signed-off-by: Oliver O'Halloran <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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This function is a one line wrapper around eeh_phb_pe_create() and despite
the name it doesn't create any eeh_dev structures. Replace it with direct
calls to eeh_phb_pe_create() since that does what it says on the tin
and removes a layer of indirection.
Signed-off-by: Oliver O'Halloran <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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So far Book3S Powerpc supported only one watchpoint. Power10 is
introducing 2nd DAWR. Enable 2nd DAWR support for Power10.
Availability of 2nd DAWR will depend on CPU_FTR_DAWR1.
Signed-off-by: Ravi Bangoria <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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2nd DAWR can be set/unset using H_SET_MODE hcall with resource value 5.
Enable powervm guest support with that. This has no effect on kvm guest
because kvm will return error if guest does hcall with resource value 5.
Signed-off-by: Ravi Bangoria <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Current H_SET_MODE hcall macro name for setting/resetting DAWR0 is
H_SET_MODE_RESOURCE_SET_DAWR. Add suffix 0 to macro name as well.
Signed-off-by: Ravi Bangoria <[email protected]>
Reviewed-by: Jordan Niethe <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Add new device-tree feature for 2nd DAWR. If this feature is present,
2nd DAWR is supported, otherwise not.
Signed-off-by: Ravi Bangoria <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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CPU_FTR_DAWR is by default enabled for host via CPU_FTRS_DT_CPU_BASE
(controlled by CONFIG_PPC_DT_CPU_FTRS). But cpu-features device-tree
node is not PAPR compatible and thus not yet used by kvm or pHyp
guests. Enable watchpoint functionality on power10 guest (both kvm
and powervm) by adding CPU_FTR_DAWR to CPU_FTRS_POWER10. Note that
this change does not enable 2nd DAWR support.
Signed-off-by: Ravi Bangoria <[email protected]>
Tested-by: Jordan Niethe <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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Signed-off-by: Ingo Molnar <[email protected]>
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From Nick's cover letter:
Linux powerpc new system call instruction and ABI
System Call Vectored (scv) ABI
==============================
The scv instruction is introduced with POWER9 / ISA3, it comes with an
rfscv counter-part. The benefit of these instructions is
performance (trading slower SRR0/1 with faster LR/CTR registers, and
entering the kernel with MSR[EE] and MSR[RI] left enabled, which can
reduce MSR updates. The scv instruction has 128 levels (not enough to
cover the Linux system call space).
Assignment and advertisement
----------------------------
The proposal is to assign scv levels conservatively, and advertise
them with HWCAP feature bits as we add support for more.
Linux has not enabled FSCR[SCV] yet, so executing the scv instruction
will cause the kernel to log a "SCV facility unavilable" message, and
deliver a SIGILL with ILL_ILLOPC to the process. Linux has defined a
HWCAP2 bit PPC_FEATURE2_SCV for SCV support, but does not set it.
This change allocates the zero level ('scv 0'), advertised with
PPC_FEATURE2_SCV, which will be used to provide normal Linux system
calls (equivalent to 'sc').
Attempting to execute scv with other levels will cause a SIGILL to be
delivered the same as before, but will not log a "SCV facility
unavailable" message (because the processor facility is enabled).
Calling convention
------------------
The proposal is for scv 0 to provide the standard Linux system call
ABI with the following differences from sc convention[1]:
- LR is to be volatile across scv calls. This is necessary because the
scv instruction clobbers LR. From previous discussion, this should
be possible to deal with in GCC clobbers and CFI.
- cr1 and cr5-cr7 are volatile. This matches the C ABI and would allow
the kernel system call exit to avoid restoring the volatile cr
registers (although we probably still would anyway to avoid
information leaks).
- Error handling: The consensus among kernel, glibc, and musl is to
move to using negative return values in r3 rather than CR0[SO]=1 to
indicate error, which matches most other architectures, and is
closer to a function call.
Notes
-----
- r0,r4-r8 are documented as volatile in the ABI, but the kernel patch
as submitted currently preserves them. This is to leave room for
deciding which way to go with these. Some small benefit was found by
preserving them[1] but I'm not convinced it's worth deviating from
the C function call ABI just for this. Release code should follow
the ABI.
Previous discussions:
https://lists.ozlabs.org/pipermail/linuxppc-dev/2020-April/208691.html
https://lists.ozlabs.org/pipermail/linuxppc-dev/2020-April/209268.html
[1] https://github.com/torvalds/linux/blob/master/Documentation/powerpc/syscall64-abi.rst
[2] https://lists.ozlabs.org/pipermail/linuxppc-dev/2020-April/209263.html
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On PAPR+ the hcall() on 0x1B0 is called H_DISABLE_AND_GET, but got
defined as H_DISABLE_AND_GETC instead.
This define was introduced with a typo in commit <b13a96cfb055>
("[PATCH] powerpc: Extends HCALL interface for InfiniBand usage"), and was
later used without having the typo noticed.
Signed-off-by: Leonardo Bras <[email protected]>
Acked-by: Paul Mackerras <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
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