Compiling with CONFIG_PPC_POWERNV=y and KVM disabled currently gives
an error like this:

  CC      arch/powerpc/kernel/dbell.o
In file included from arch/powerpc/kernel/dbell.c:20:0:
arch/powerpc/include/asm/kvm_ppc.h: In function ‘xics_on_xive’:
arch/powerpc/include/asm/kvm_ppc.h:625:9: error: implicit declaration of function ‘xive_enabled’ [-Werror=implicit-function-declaration]
  return xive_enabled() && cpu_has_feature(CPU_FTR_HVMODE);
         ^
cc1: all warnings being treated as errors
scripts/Makefile.build:276: recipe for target 'arch/powerpc/kernel/dbell.o' failed
make[3]: *** [arch/powerpc/kernel/dbell.o] Error 1

Fix this by making the xics_on_xive() definition conditional on the
same symbol (CONFIG_KVM_BOOK3S_64_HANDLER) that determines whether we
include <asm/xive.h> or not, since that's the header that defines
xive_enabled().

Fixes: 03f95332 ("KVM: PPC: Book3S: Allow XICS emulation to work in nested hosts using XIVE")
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>

When the hash MMU is active the AMR, IAMR and UAMOR are used for
pkeys. The AMR is directly writable by user space, and the UAMOR masks
those writes, meaning both registers are effectively user register
state. The IAMR is used to create an execute only key.

Also we must maintain the value of at least the AMR when running in
process context, so that any memory accesses done by the kernel on
behalf of the process are correctly controlled by the AMR.

Although we are correctly switching all registers when going into a
guest, on returning to the host we just write 0 into all regs, except
on Power9 where we restore the IAMR correctly.

This could be observed by a user process if it writes the AMR, then
runs a guest and we then return immediately to it without
rescheduling. Because we have written 0 to the AMR that would have the
effect of granting read/write permission to pages that the process was
trying to protect.

In addition, when using the Radix MMU, the AMR can prevent inadvertent
kernel access to userspace data, writing 0 to the AMR disables that
protection.

So save and restore AMR, IAMR and UAMOR.

Fixes: cf43d3b2 ("powerpc: Enable pkey subsystem")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: NRussell Currey <ruscur@russell.cc>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Acked-by: NPaul Mackerras <paulus@ozlabs.org>

The anon fd's ops releases the KVM reference in the release hook.
However we reference the KVM object after we create the fd so there is
small window when the release function can be called and
dereferenced the KVM object which potentially may free it.

It is not a problem at the moment as the file is created and KVM is
referenced under the KVM lock and the release function obtains the same
lock before dereferencing the KVM (although the lock is not held when
calling kvm_put_kvm()) but it is potentially fragile against future changes.

This references the KVM object before creating a file.
Signed-off-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>

Currently trying to build without IOMMU support will fail:

  (.text+0x1380): undefined reference to `kvmppc_h_get_tce'
  (.text+0x1384): undefined reference to `kvmppc_rm_h_put_tce'
  (.text+0x149c): undefined reference to `kvmppc_rm_h_stuff_tce'
  (.text+0x14a0): undefined reference to `kvmppc_rm_h_put_tce_indirect'

This happens because turning off IOMMU support will prevent
book3s_64_vio_hv.c from being built because it is only built when
SPAPR_TCE_IOMMU is set, which depends on IOMMU support.

Fix it using ifdefs for the undefined references.

Fixes: 76d837a4 ("KVM: PPC: Book3S PR: Don't include SPAPR TCE code on non-pseries platforms")
Signed-off-by: NJordan Niethe <jniethe5@gmail.com>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>

This adds an "in_guest" parameter to machine_check_print_event_info()
so that we can avoid trying to translate guest NIP values into
symbolic form using the host kernel's symbol table.
Reviewed-by: NAravinda Prasad <aravinda@linux.vnet.ibm.com>
Reviewed-by: NMahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This makes the handling of machine check interrupts that occur inside
a guest simpler and more robust, with less done in assembler code and
in real mode.

Now, when a machine check occurs inside a guest, we always get the
machine check event struct and put a copy in the vcpu struct for the
vcpu where the machine check occurred.  We no longer call
machine_check_queue_event() from kvmppc_realmode_mc_power7(), because
on POWER8, when a vcpu is running on an offline secondary thread and
we call machine_check_queue_event(), that calls irq_work_queue(),
which doesn't work because the CPU is offline, but instead triggers
the WARN_ON(lazy_irq_pending()) in pnv_smp_cpu_kill_self() (which
fires again and again because nothing clears the condition).

All that machine_check_queue_event() actually does is to cause the
event to be printed to the console.  For a machine check occurring in
the guest, we now print the event in kvmppc_handle_exit_hv()
instead.

The assembly code at label machine_check_realmode now just calls C
code and then continues exiting the guest.  We no longer either
synthesize a machine check for the guest in assembly code or return
to the guest without a machine check.

The code in kvmppc_handle_exit_hv() is extended to handle the case
where the guest is not FWNMI-capable.  In that case we now always
synthesize a machine check interrupt for the guest.  Previously, if
the host thinks it has recovered the machine check fully, it would
return to the guest without any notification that the machine check
had occurred.  If the machine check was caused by some action of the
guest (such as creating duplicate SLB entries), it is much better to
tell the guest that it has caused a problem.  Therefore we now always
generate a machine check interrupt for guests that are not
FWNMI-capable.
Reviewed-by: NAravinda Prasad <aravinda@linux.vnet.ibm.com>
Reviewed-by: NMahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

kvmhv_p9_guest_entry() implements a fast-path guest entry for Power9
when guest and host are both running with the Radix MMU.

Currently in that path we don't save the host AMR (Authority Mask
Register) value, and we always restore 0 on return to the host. That
is OK at the moment because the AMR is not used for storage keys with
the Radix MMU.

However we plan to start using the AMR on Radix to prevent the kernel
from reading/writing to userspace outside of copy_to/from_user(). In
order to make that work we need to save/restore the AMR value.

We only restore the value if it is different from the guest value,
which is already in the register when we exit to the host. This should
mean we rarely need to actually restore the value when running a
modern Linux as a guest, because it will be using the same value as
us.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
Tested-by: NRussell Currey <ruscur@russell.cc>

grow_halt_poll_ns() have a strange behaviour in case
(vcpu->halt_poll_ns != 0) &&
(vcpu->halt_poll_ns < halt_poll_ns_grow_start).

In this case, vcpu->halt_poll_ns will be multiplied by grow factor
(halt_poll_ns_grow) which will require several grow iteration in order
to reach a value bigger than halt_poll_ns_grow_start.
This means that growing vcpu->halt_poll_ns from value of 0 is slower
than growing it from a positive value less than halt_poll_ns_grow_start.
Which is misleading and inaccurate.

Fix issue by changing grow_halt_poll_ns() to set vcpu->halt_poll_ns
to halt_poll_ns_grow_start in any case that
(vcpu->halt_poll_ns < halt_poll_ns_grow_start).
Regardless if vcpu->halt_poll_ns is 0.

use READ_ONCE to get a consistent number for all cases.
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: NLiran Alon <liran.alon@oracle.com>
Signed-off-by: NNir Weiner <nir.weiner@oracle.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The hard-coded value 10000 in grow_halt_poll_ns() stands for the initial
start value when raising up vcpu->halt_poll_ns.
It actually sets the first timeout to the first polling session.
This value has significant effect on how tolerant we are to outliers.
On the standard case, higher value is better - we will spend more time
in the polling busyloop, handle events/interrupts faster and result
in better performance.
But on outliers it puts us in a busy loop that does nothing.
Even if the shrink factor is zero, we will still waste time on the first
iteration.
The optimal value changes between different workloads. It depends on
outliers rate and polling sessions length.
As this value has significant effect on the dynamic halt-polling
algorithm, it should be configurable and exposed.
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: NLiran Alon <liran.alon@oracle.com>
Signed-off-by: NNir Weiner <nir.weiner@oracle.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

grow_halt_poll_ns() have a strange behavior in case
(halt_poll_ns_grow == 0) && (vcpu->halt_poll_ns != 0).

In this case, vcpu->halt_pol_ns will be set to zero.
That results in shrinking instead of growing.

Fix issue by changing grow_halt_poll_ns() to not modify
vcpu->halt_poll_ns in case halt_poll_ns_grow is zero
Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: NLiran Alon <liran.alon@oracle.com>
Signed-off-by: NNir Weiner <nir.weiner@oracle.com>
Suggested-by: NLiran Alon <liran.alon@oracle.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

kvm_arch_memslots_updated() is at this point in time an x86-specific
hook for handling MMIO generation wraparound.  x86 stashes 19 bits of
the memslots generation number in its MMIO sptes in order to avoid
full page fault walks for repeat faults on emulated MMIO addresses.
Because only 19 bits are used, wrapping the MMIO generation number is
possible, if unlikely.  kvm_arch_memslots_updated() alerts x86 that
the generation has changed so that it can invalidate all MMIO sptes in
case the effective MMIO generation has wrapped so as to avoid using a
stale spte, e.g. a (very) old spte that was created with generation==0.

Given that the purpose of kvm_arch_memslots_updated() is to prevent
consuming stale entries, it needs to be called before the new generation
is propagated to memslots.  Invalidating the MMIO sptes after updating
memslots means that there is a window where a vCPU could dereference
the new memslots generation, e.g. 0, and incorrectly reuse an old MMIO
spte that was created with (pre-wrap) generation==0.

Fixes: e59dbe09 ("KVM: Introduce kvm_arch_memslots_updated()")
Cc: <stable@vger.kernel.org>
Signed-off-by: NSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This adds an entry to the kvm_stats_debugfs directory which provides the
number of large (2M or 1G) pages which have been used to setup the guest
mappings, for radix guests.
Signed-off-by: NSuraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>

The SPAPR TCE KVM device references all hardware IOMMU tables assigned to
some IOMMU group to ensure that in-kernel KVM acceleration of H_PUT_TCE
can work. The tables are references when an IOMMU group gets registered
with the VFIO KVM device by the KVM_DEV_VFIO_GROUP_ADD ioctl;
KVM_DEV_VFIO_GROUP_DEL calls into the dereferencing code
in kvm_spapr_tce_release_iommu_group() which walks through the list of
LIOBNs, finds a matching IOMMU table and calls kref_put() when found.

However that code stops after the very first successful derefencing
leaving other tables referenced till the SPAPR TCE KVM device is destroyed
which normally happens on guest reboot or termination so if we do hotplug
and unplug in a loop, we are leaking IOMMU tables here.

This removes a premature return to let kvm_spapr_tce_release_iommu_group()
find and dereference all attached tables.

Fixes: 121f80ba ("KVM: PPC: VFIO: Add in-kernel acceleration for VFIO")
Signed-off-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>

Devices on the KVM_FAST_MMIO_BUS by definition have length zero and are
thus used for notification purposes rather than data transfer. For
example eventfd for virtio devices.

This means that when emulating mmio instructions which target devices on
this bus we can immediately handle them and return without needing to load
the instruction from guest memory.

For now we restrict this to stores as this is the only use case at
present.

For a normal guest the effect is negligible, however for a nested guest
we save on the order of 5us per access.
Signed-off-by: NSuraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>

Currently, the KVM code assumes that if the host kernel is using the
XIVE interrupt controller (the new interrupt controller that first
appeared in POWER9 systems), then the in-kernel XICS emulation will
use the XIVE hardware to deliver interrupts to the guest.  However,
this only works when the host is running in hypervisor mode and has
full access to all of the XIVE functionality.  It doesn't work in any
nested virtualization scenario, either with PR KVM or nested-HV KVM,
because the XICS-on-XIVE code calls directly into the native-XIVE
routines, which are not initialized and cannot function correctly
because they use OPAL calls, and OPAL is not available in a guest.

This means that using the in-kernel XICS emulation in a nested
hypervisor that is using XIVE as its interrupt controller will cause a
(nested) host kernel crash.  To fix this, we change most of the places
where the current code calls xive_enabled() to select between the
XICS-on-XIVE emulation and the plain XICS emulation to call a new
function, xics_on_xive(), which returns false in a guest.

However, there is a further twist.  The plain XICS emulation has some
functions which are used in real mode and access the underlying XICS
controller (the interrupt controller of the host) directly.  In the
case of a nested hypervisor, this means doing XICS hypercalls
directly.  When the nested host is using XIVE as its interrupt
controller, these hypercalls will fail.  Therefore this also adds
checks in the places where the XICS emulation wants to access the
underlying interrupt controller directly, and if that is XIVE, makes
the code use the virtual mode fallback paths, which call generic
kernel infrastructure rather than doing direct XICS access.
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>
Reviewed-by: NCédric Le Goater <clg@kaod.org>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>

The header search path -I. in kernel Makefiles is very suspicious;
it allows the compiler to search for headers in the top of $(srctree),
where obviously no header file exists.

Commit 46f43c6e ("KVM: powerpc: convert marker probes to event
trace") first added these options, but they are completely useless.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>

Replace kmalloc_node and memset with kzalloc_node
Signed-off-by: Nwangbo <wang.bo116@zte.com.cn>
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>

Recent kernels, since commit e15a4fea ("powerpc/64s/hash: Add
some SLB debugging tests", 2018-10-03) use the slbfee. instruction,
which PR KVM currently does not have code to emulate.  Consequently
recent kernels fail to boot under PR KVM.  This adds emulation of
slbfee., enabling these kernels to boot successfully.
Signed-off-by: NPaul Mackerras <paulus@ozlabs.org>

When binding an SCM volume to a physical address the hypervisor has the
option to return early with a continue token with the expectation that
the guest will resume the bind operation until it completes. A quirk of
this interface is that the bind address will only be returned by the
first bind h-call and the subsequent calls will return
0xFFFF_FFFF_FFFF_FFFF for the bind address.

We currently do not save the address returned by the first h-call. As a
result we will use the junk address as the base of the bound region if
the hypervisor decides to split the bind across multiple h-calls. This
bug was found when testing with very large SCM volumes where the bind
process would take more time than they hypervisor's internal h-call time
limit would allow. This patch fixes the issue by saving the bind address
from the first call.

Cc: stable@vger.kernel.org
Fixes: b5beae5e ("powerpc/pseries: Add driver for PAPR SCM regions")
Signed-off-by: NOliver O'Halloran <oohall@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

With support for split pmd lock, we use pmd page pmd_huge_pte pointer
to store the deposited page table. In those config when we move page
tables we need to make sure we move the deposited page table to the
correct pmd page. Otherwise this can result in crash when we withdraw
of deposited page table because we can find the pmd_huge_pte NULL.

eg:

  __split_huge_pmd+0x1070/0x1940
  __split_huge_pmd+0xe34/0x1940 (unreliable)
  vma_adjust_trans_huge+0x110/0x1c0
  __vma_adjust+0x2b4/0x9b0
  __split_vma+0x1b8/0x280
  __do_munmap+0x13c/0x550
  sys_mremap+0x220/0x7e0
  system_call+0x5c/0x70

Fixes: 675d9952 ("powerpc/book3s64: Enable split pmd ptlock.")
Cc: stable@vger.kernel.org # v4.18+
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Commit 8ce5f841 ("of: Remove struct device_node.type pointer")
removed struct device_node.type pointer, but the conversion to use
of_node_is_type() accessor was missed in chrp_init_IRQ().

Fixes: 8ce5f841 ("of: Remove struct device_node.type pointer")
Reported-by: Nkbuild test robot <lkp@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Acked-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NRob Herring <robh@kernel.org>

Recently in commit fbf508da ("powerpc: split compat syscall table
out from native table") we changed the layout of the system call
table. Instead of having two entries for each syscall number, one for
the regular entry point and one for the compat entry point, we now
have separate tables for regular and compat entry points.

This inadvertently broke syscall tracing (CONFIG_FTRACE_SYSCALLS),
because our implementation of arch_syscall_addr() knew about the
layout of the table (it did nr * 2).

We can fix it just by dropping our version of arch_syscall_addr() and
using the generic version which does:

	return (unsigned long)sys_call_table[nr];

Fixes: fbf508da ("powerpc: split compat syscall table out from native table")
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Commit 3be2df00 ("powerpc/pseries/npu: Enable platform support")
added a call to pnv_npu2_init() in pseries code. This causes a build
break if we build with CONFIG_PPC_PSERIES && !CONFIG_PPC_POWERNV:

  powerpc64le-pc-linux-gnu-ld: arch/powerpc/platforms/pseries/pci.o: in function `pSeries_final_fixup':
  pci.c:(.init.text+0x1b0): undefined reference to `pnv_npu2_init'

This commit therefore wraps that line in an ifdef, so that pseries
builds without powernv.

Fixes: 3be2df00 ("powerpc/pseries/npu: Enable platform support")
Signed-off-by: NJason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
[mpe: Frob change log a bit to blame a different commit]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

My recent commit to fix the printf warnings in ocm.c got the format
specifier wrong, because I copied it from the documentation without
realising the square brackets are not meant as literals.

This results in the address being suffixed with a literal "[p]".

Actually tested this time:

  # cat info /sys/kernel/debug/ppc4xx_ocm
  PhysAddr     : 0x0000000400040000
  ...
  NC.PhysAddr  : 0x0000000400040000
  ...
  C.PhysAddr   : 0x0000000000000000

Fixes: 52b88fa1 ("powerpc/4xx/ocm: Fix phys_addr_t printf warnings")
Reported-by: NChristian Lamparter <chunkeey@gmail.com>
Tested-by: NChristian Lamparter <chunkeey@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

With a recent change around IOMMU group, a system with an opencapi
adapter is no longer booting and we get a kernel oops:

  BUG: Kernel NULL pointer dereference at 0x00000028
  Faulting instruction address: 0xc0000000000aa38c
  ...
  NIP pnv_try_setup_npu_table_group+0x1c/0x1a0
  LR  pnv_pci_ioda_fixup+0x1f8/0x660
  Call Trace:
    pnv_try_setup_npu_table_group+0x60/0x
    pnv_pci_ioda_fixup+0x20c/0x660
    pcibios_resource_survey+0x2c8/0x31c
    pcibios_init+0xb0/0xe4
    do_one_initcall+0x64/0x264
    kernel_init_freeable+0x36c/0x468
    kernel_init+0x2c/0x148
    ret_from_kernel_thread+0x5c/0x68

An opencapi device is using a device PE, so the current code breaks
because pe->pbus is not defined.

More generally, there's no need to define an IOMMU group for opencapi,
as the device sends real addresses directly (admittedly, the
virtualization story is yet to be written). So let's fix it by
skipping the IOMMU group setup for opencapi PHBs.

Fixes: 0bd97167 ("powerpc/powernv/npu: Add compound IOMMU groups")
Signed-off-by: NFrederic Barrat <fbarrat@linux.ibm.com>
Reviewed-by: NGreg Kurz <groug@kaod.org>
Reviewed-by: NAndrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Commit e1c3743e ("powerpc/tm: Set MSR[TS] just prior to recheckpoint")
moved a code block around and this block uses a 'msr' variable outside of
the CONFIG_PPC_TRANSACTIONAL_MEM, however the 'msr' variable is declared
inside a CONFIG_PPC_TRANSACTIONAL_MEM block, causing a possible error when
CONFIG_PPC_TRANSACTION_MEM is not defined.

	error: 'msr' undeclared (first use in this function)

This is not causing a compilation error in the mainline kernel, because
'msr' is being used as an argument of MSR_TM_ACTIVE(), which is defined as
the following when CONFIG_PPC_TRANSACTIONAL_MEM is *not* set:

	#define MSR_TM_ACTIVE(x) 0

This patch just fixes this issue avoiding the 'msr' variable usage outside
the CONFIG_PPC_TRANSACTIONAL_MEM block, avoiding trusting in the
MSR_TM_ACTIVE() definition.

Cc: stable@vger.kernel.org
Reported-by: NChristoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Fixes: e1c3743e ("powerpc/tm: Set MSR[TS] just prior to recheckpoint")
Signed-off-by: NBreno Leitao <leitao@debian.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Commit 8c8c10b9 ("powerpc/8xx: fix handling of early NULL pointer
dereference") moved the loading of r6 earlier in the code. As some
functions are called inbetween, r6 needs to be loaded again with the
address of swapper_pg_dir in order to set PTE pointers for
the Abatron BDI.

Fixes: 8c8c10b9 ("powerpc/8xx: fix handling of early NULL pointer dereference")
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

There is a typo so we accidentally allocate enough memory for a pointer
when we wanted to allocate enough for a struct.

Fixes: 0bd97167 ("powerpc/powernv/npu: Add compound IOMMU groups")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

We already need to zero out memory for dma_alloc_coherent(), as such
using dma_zalloc_coherent() is superflous. Phase it out.

This change was generated with the following Coccinelle SmPL patch:

@ replace_dma_zalloc_coherent @
expression dev, size, data, handle, flags;
@@

-dma_zalloc_coherent(dev, size, handle, flags)
+dma_alloc_coherent(dev, size, handle, flags)
Suggested-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NLuis Chamberlain <mcgrof@kernel.org>
[hch: re-ran the script on the latest tree]
Signed-off-by: NChristoph Hellwig <hch@lst.de>

On each sample, Monitor Mode Control Register A (MMCRA) content is
saved in pt_regs. MMCRA does not have a entry as-is in the pt_regs but
instead, MMCRA content is saved in the "dsisr" register of pt_regs.

Patch adds another entry to the perf_regs structure to include the
"MMCRA" printing which internally maps to the "dsisr" of pt_regs.

It also check for the MMCRA availability in the platform and present
value accordingly

mpe: This was the 2nd patch in a series with commit 333804dc
("powerpc/perf: Update perf_regs structure to include SIER") but I
accidentally only merged the 1st patch, so merge this one now.
Signed-off-by: NMadhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Now that Kbuild automatically creates asm-generic wrappers for missing
mandatory headers, it is redundant to list the same headers in
generic-y and mandatory-y.
Suggested-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NSam Ravnborg <sam@ravnborg.org>

These comments are leftovers of commit fcc8487d ("uapi: export all
headers under uapi directories").

Prior to that commit, exported headers must be explicitly added to
header-y. Now, all headers under the uapi/ directories are exported.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>

Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label".

The jump label is controlled by HAVE_JUMP_LABEL, which is defined
like this:

  #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
  # define HAVE_JUMP_LABEL
  #endif

We can improve this by testing 'asm goto' support in Kconfig, then
make JUMP_LABEL depend on CC_HAS_ASM_GOTO.

Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will
match to the real kernel capability.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: NSedat Dilek <sedat.dilek@gmail.com>

Patch series "Add support for fast mremap".

This series speeds up the mremap(2) syscall by copying page tables at
the PMD level even for non-THP systems.  There is concern that the extra
'address' argument that mremap passes to pte_alloc may do something
subtle architecture related in the future that may make the scheme not
work.  Also we find that there is no point in passing the 'address' to
pte_alloc since its unused.  This patch therefore removes this argument
tree-wide resulting in a nice negative diff as well.  Also ensuring
along the way that the enabled architectures do not do anything funky
with the 'address' argument that goes unnoticed by the optimization.

Build and boot tested on x86-64.  Build tested on arm64.  The config
enablement patch for arm64 will be posted in the future after more
testing.

The changes were obtained by applying the following Coccinelle script.
(thanks Julia for answering all Coccinelle questions!).
Following fix ups were done manually:
* Removal of address argument from  pte_fragment_alloc
* Removal of pte_alloc_one_fast definitions from m68k and microblaze.

// Options: --include-headers --no-includes
// Note: I split the 'identifier fn' line, so if you are manually
// running it, please unsplit it so it runs for you.

virtual patch

@pte_alloc_func_def depends on patch exists@
identifier E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
type T2;
@@

 fn(...
- , T2 E2
 )
 { ... }

@pte_alloc_func_proto_noarg depends on patch exists@
type T1, T2, T3, T4;
identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

(
- T3 fn(T1, T2);
+ T3 fn(T1);
|
- T3 fn(T1, T2, T4);
+ T3 fn(T1, T2);
)

@pte_alloc_func_proto depends on patch exists@
identifier E1, E2, E4;
type T1, T2, T3, T4;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

(
- T3 fn(T1 E1, T2 E2);
+ T3 fn(T1 E1);
|
- T3 fn(T1 E1, T2 E2, T4 E4);
+ T3 fn(T1 E1, T2 E2);
)

@pte_alloc_func_call depends on patch exists@
expression E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

 fn(...
-,  E2
 )

@pte_alloc_macro depends on patch exists@
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
identifier a, b, c;
expression e;
position p;
@@

(
- #define fn(a, b, c) e
+ #define fn(a, b) e
|
- #define fn(a, b) e
+ #define fn(a) e
)

Link: http://lkml.kernel.org/r/20181108181201.88826-2-joelaf@google.comSigned-off-by: NJoel Fernandes (Google) <joel@joelfernandes.org>
Suggested-by: NKirill A. Shutemov <kirill@shutemov.name>
Acked-by: NKirill A. Shutemov <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

These two architectures actually had an intentional use of the 'type'
argument to access_ok() just to avoid warnings.

I had actually noticed the powerpc one, but forgot to then fix it up.
And I missed the sparc32 case entirely.

This is hopefully all of it.
Reported-by: NMathieu Malaterre <malat@debian.org>
Reported-by: NGuenter Roeck <linux@roeck-us.net>
Fixes: 96d4f267 ("Remove 'type' argument from access_ok() function")
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In commit 05a4ab82 ("powerpc/uaccess: fix warning/error with
access_ok()") an attempt was made to remove a warning by referencing
the variable `type`. However in commit 96d4f267 ("Remove 'type'
argument from access_ok() function") the variable `type` has been
removed, breaking the build:

  arch/powerpc/include/asm/uaccess.h:66:32: error: ‘type’ undeclared (first use in this function)

This essentially reverts commit 05a4ab82 ("powerpc/uaccess: fix
warning/error with access_ok()") to fix the error.

Fixes: 96d4f267 ("Remove 'type' argument from access_ok() function")
Signed-off-by: NMathieu Malaterre <malat@debian.org>
[mpe: Reword change log slightly.]
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access.  But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model.  And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

 - csky still had the old "verify_area()" name as an alias.

 - the iter_iov code had magical hardcoded knowledge of the actual
   values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
   really used it)

 - microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something.  Any missed conversion should be trivially fixable, though.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

checkpatch.pl reports the following:

  WARNING: struct kgdb_arch should normally be const
  #28: FILE: arch/mips/kernel/kgdb.c:397:
  +struct kgdb_arch arch_kgdb_ops = {

This report makes sense, as all other ops struct, this
one should also be const. This patch does the change.

Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: x86@kernel.org
Acked-by: NDaniel Thompson <daniel.thompson@linaro.org>
Acked-by: NPaul Burton <paul.burton@mips.com>
Signed-off-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Acked-by: NBorislav Petkov <bp@suse.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>

When I had lockdep turned on and dropped into kgdb I got a nice splat
on my system.  Specifically it hit:
  DEBUG_LOCKS_WARN_ON(current->hardirq_context)

Specifically it looked like this:
  sysrq: SysRq : DEBUG
  ------------[ cut here ]------------
  DEBUG_LOCKS_WARN_ON(current->hardirq_context)
  WARNING: CPU: 0 PID: 0 at .../kernel/locking/lockdep.c:2875 lockdep_hardirqs_on+0xf0/0x160
  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.19.0 #27
  pstate: 604003c9 (nZCv DAIF +PAN -UAO)
  pc : lockdep_hardirqs_on+0xf0/0x160
  ...
  Call trace:
   lockdep_hardirqs_on+0xf0/0x160
   trace_hardirqs_on+0x188/0x1ac
   kgdb_roundup_cpus+0x14/0x3c
   kgdb_cpu_enter+0x53c/0x5cc
   kgdb_handle_exception+0x180/0x1d4
   kgdb_compiled_brk_fn+0x30/0x3c
   brk_handler+0x134/0x178
   do_debug_exception+0xfc/0x178
   el1_dbg+0x18/0x78
   kgdb_breakpoint+0x34/0x58
   sysrq_handle_dbg+0x54/0x5c
   __handle_sysrq+0x114/0x21c
   handle_sysrq+0x30/0x3c
   qcom_geni_serial_isr+0x2dc/0x30c
  ...
  ...
  irq event stamp: ...45
  hardirqs last  enabled at (...44): [...] __do_softirq+0xd8/0x4e4
  hardirqs last disabled at (...45): [...] el1_irq+0x74/0x130
  softirqs last  enabled at (...42): [...] _local_bh_enable+0x2c/0x34
  softirqs last disabled at (...43): [...] irq_exit+0xa8/0x100
  ---[ end trace adf21f830c46e638 ]---

Looking closely at it, it seems like a really bad idea to be calling
local_irq_enable() in kgdb_roundup_cpus().  If nothing else that seems
like it could violate spinlock semantics and cause a deadlock.

Instead, let's use a private csd alongside
smp_call_function_single_async() to round up the other CPUs.  Using
smp_call_function_single_async() doesn't require interrupts to be
enabled so we can remove the offending bit of code.

In order to avoid duplicating this across all the architectures that
use the default kgdb_roundup_cpus(), we'll add a "weak" implementation
to debug_core.c.

Looking at all the people who previously had copies of this code,
there were a few variants.  I've attempted to keep the variants
working like they used to.  Specifically:
* For arch/arc we passed NULL to kgdb_nmicallback() instead of
  get_irq_regs().
* For arch/mips there was a bit of extra code around
  kgdb_nmicallback()

NOTE: In this patch we will still get into trouble if we try to round
up a CPU that failed to round up before.  We'll try to round it up
again and potentially hang when we try to grab the csd lock.  That's
not new behavior but we'll still try to do better in a future patch.
Suggested-by: NDaniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>

The function kgdb_roundup_cpus() was passed a parameter that was
documented as:

> the flags that will be used when restoring the interrupts. There is
> local_irq_save() call before kgdb_roundup_cpus().

Nobody used those flags.  Anyone who wanted to temporarily turn on
interrupts just did local_irq_enable() and local_irq_disable() without
looking at them.  So we can definitely remove the flags.
Signed-off-by: NDouglas Anderson <dianders@chromium.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>