Commit graph

144021 commits

Author SHA1 Message Date
Nicholas Piggin d50614fa45 powerpc/64s: Explicitly add vector features to CPU_FTRS_POSSIBLE
ALTIVEC and VSX features are not added by to default to the POWERx CPU
feature sets because they are intended to be enabled by firmware.
Currently they end up in CPU_FTRS_POSSIBLE due to their inclusion in
other the set for other CPUs, eg. PPC970.

But they should be added individually to the CPU_FTRS_POSSIBLE set,
because if we reduce the set of CPUs that are built-for they may
disappear from the possible mask.

It already contains CPU_FTR_VSX, so add ALTIVEC. The _COMP features
should be used because they won't be present if compiled out.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add detail to change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:48 +11:00
Nicholas Piggin b842bd0f7a powerpc/64s: Add all POWER9 features to CPU_FTRS_ALWAYS
It's not a bug to have features missing in CPU_FTR_ALWAYS, but it is a
missed opportunity for optimisation.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:48 +11:00
Mark Greer 147704534e powerpc/boot: Remove duplicate typedefs from libfdt_env.h
When building a uImage or zImage using ppc6xx_defconfig and some other
defconfigs, the following error occurs with GCC 4.5.1:

  /arch/powerpc/boot/libfdt_env.h:10:13: error: redefinition of typedef 'uint32_t'
  /arch/powerpc/boot/types.h:21:13: note: previous declaration of 'uint32_t' was here
  /arch/powerpc/boot/libfdt_env.h:11:13: error: redefinition of typedef 'uint64_t'
  /arch/powerpc/boot/types.h:22:13: note: previous declaration of 'uint64_t' was here

The problem is that commit 656ad58ef1 (powerpc/boot: Add OPAL
console to epapr wrappers) adds typedefs for uint32_t and uint64_t to
type.h but doesn't remove the pre-existing (and now duplicate)
typedefs from libfdt_env.h.

Fix the error by removing the duplicate typedefs from libfdt_env.h

Signed-off-by: Mark Greer <mgreer@animalcreek.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:47 +11:00
Nicholas Piggin 8c1c7fb0b5 powerpc/64s/idle: avoid sync for KVM state when waking from idle
When waking from a CPU idle instruction (e.g., nap or stop), the sync
for ordering the KVM secondary thread state can be avoided if there
wakeup is coming from a kernel context rather than KVM context.

This improves performance for ping-pong benchmark with the stop0 idle
state by 0.46% for 2 threads in the same core, and 1.02% for different
cores.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:47 +11:00
Nicholas Piggin 3d4fbffdd7 powerpc/64s/idle: POWER9 implement a separate idle stop function for hotplug
Implement a new function to invoke stop, power9_offline_stop, which is
like power9_idle_stop but used by the cpu hotplug code.

Move KVM secondary state manipulation code to the offline case.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:46 +11:00
Nicholas Piggin d40b6768e4 powerpc/64s: sreset panic if there is no debugger or crash dump handlers
system_reset_exception does most of its own crash handling now,
invoking the debugger or crash dumps if they are registered. If not,
then it goes through to die() to print stack traces, and then is
supposed to panic (according to comments).

However after die() prints oopses, it does its own handling which
doesn't allow system_reset_exception to panic (e.g., it may just
kill the current process). This patch causes sreset exceptions to
return from die after it prints messages but before acting.

This also stops die from invoking the debugger on 0x100 crashes.
system_reset_exception similarly calls the debugger. It had been
thought this was harmless (because if the debugger was disabled,
neither call would fire, and if it was enabled the first call
would return). However in some cases like xmon 'X' command, the
debugger returns 0, which currently causes it to be entered
again (first in system_reset_exception, then in die), which is
confusing.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:46 +11:00
Nicholas Piggin 15b4dd7981 powerpc/64s: return more carefully from sreset NMI
System Reset, being an NMI, must return more carefully than other
interrupts. It has traditionally returned via the nromal return
from exception path, but that has a number of problems.

- r13 does not get restored if returning to kernel. This is for
  interrupts which may cause a context switch, which sreset will
  never do. Interrupting OPAL (which uses a different r13) is one
  place where this causes breakage.

- It may cause several other problems returning to kernel with
  preempt or TIF_EMULATE_STACK_STORE if it hits at the wrong time.

It's safer just to have a simple restore and return, like machine
check which is the other NMI.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:45 +11:00
Michael Neuling f0295e047f powerpc/eeh: Fix race with driver un/bind
The current EEH callbacks can race with a driver unbind. This can
result in a backtraces like this:

  EEH: Frozen PHB#0-PE#1fc detected
  EEH: PE location: S000009, PHB location: N/A
  CPU: 2 PID: 2312 Comm: kworker/u258:3 Not tainted 4.15.6-openpower1 #2
  Workqueue: nvme-wq nvme_reset_work [nvme]
  Call Trace:
    dump_stack+0x9c/0xd0 (unreliable)
    eeh_dev_check_failure+0x420/0x470
    eeh_check_failure+0xa0/0xa4
    nvme_reset_work+0x138/0x1414 [nvme]
    process_one_work+0x1ec/0x328
    worker_thread+0x2e4/0x3a8
    kthread+0x14c/0x154
    ret_from_kernel_thread+0x5c/0xc8
  nvme nvme1: Removing after probe failure status: -19
  <snip>
  cpu 0x23: Vector: 300 (Data Access) at [c000000ff50f3800]
      pc: c0080000089a0eb0: nvme_error_detected+0x4c/0x90 [nvme]
      lr: c000000000026564: eeh_report_error+0xe0/0x110
      sp: c000000ff50f3a80
     msr: 9000000000009033
     dar: 400
   dsisr: 40000000
    current = 0xc000000ff507c000
    paca    = 0xc00000000fdc9d80   softe: 0        irq_happened: 0x01
      pid   = 782, comm = eehd
  Linux version 4.15.6-openpower1 (smc@smc-desktop) (gcc version 6.4.0 (Buildroot 2017.11.2-00008-g4b6188e)) #2 SM                                             P Tue Feb 27 12:33:27 PST 2018
  enter ? for help
    eeh_report_error+0xe0/0x110
    eeh_pe_dev_traverse+0xc0/0xdc
    eeh_handle_normal_event+0x184/0x4c4
    eeh_handle_event+0x30/0x288
    eeh_event_handler+0x124/0x170
    kthread+0x14c/0x154
    ret_from_kernel_thread+0x5c/0xc8

The first part is an EEH (on boot), the second half is the resulting
crash. nvme probe starts the nvme_reset_work() worker thread. This
worker thread starts touching the device which see a device error
(EEH) and hence queues up an event in the powerpc EEH worker
thread. nvme_reset_work() then continues and runs
nvme_remove_dead_ctrl_work() which results in unbinding the driver
from the device and hence releases all resources. At the same time,
the EEH worker thread starts doing the EEH .error_detected() driver
callback, which no longer works since the resources have been freed.

This fixes the problem in the same way the generic PCIe AER code (in
drivers/pci/pcie/aer/aerdrv_core.c) does. It makes the EEH code hold
the device_lock() while performing the driver EEH callbacks and
associated code. This ensures either the callbacks are no longer
register, or if they are registered the driver will not be removed
from underneath us.

This has been broken forever. The EEH call backs were first introduced
in 2005 (in 77bd741561) but it's not clear if a lock was needed back
then.

Fixes: 77bd741561 ("[PATCH] powerpc: PCI Error Recovery: PPC64 core recovery routines")
Cc: stable@vger.kernel.org # v2.6.16+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:45 +11:00
Thiago Jung Bauermann bf8a1abc3d powerpc/kexec_file: Fix error code when trying to load kdump kernel
kexec_file_load() on powerpc doesn't support kdump kernels yet, so it
returns -ENOTSUPP in that case.

I've recently learned that this errno is internal to the kernel and
isn't supposed to be exposed to userspace. Therefore, change to
-EOPNOTSUPP which is defined in an uapi header.

This does indeed make kexec-tools happier. Before the patch, on
ppc64le:

  # ~bauermann/src/kexec-tools/build/sbin/kexec -s -p /boot/vmlinuz
  kexec_file_load failed: Unknown error 524

After the patch:

  # ~bauermann/src/kexec-tools/build/sbin/kexec -s -p /boot/vmlinuz
  kexec_file_load failed: Operation not supported

Fixes: a0458284f0 ("powerpc: Add support code for kexec_file_load()")
Cc: stable@vger.kernel.org # v4.10+
Reported-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Reviewed-by: Simon Horman <horms@verge.net.au>
Reviewed-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:44 +11:00
Jonathan Neuschäfer 7e1405917c powerpc/mm/32: Remove the reserved memory hack
This hack, introduced in commit c5df7f7751 ("powerpc: allow ioremap
within reserved memory regions") is now unnecessary.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:44 +11:00
Jonathan Neuschäfer 57deb8fea0 powerpc/wii: Don't rely on the reserved memory hack
Because the two memory blocks (usually called MEM1 and MEM2) are not
merged anymore, __request_region in kernel/resource.c will correctly
allow reserving regions in the physical address space between MEM1 and
MEM2, where many important peripherals are (GPIO, MMC, USB, ...).

A previous change to __ioremap_caller in arch/powerpc/mm/pgtable_32.c
ensures that multiple memblocks are properly considered in ioremap; this
makes it unnecessary to set __allow_ioremap_reserved.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:43 +11:00
Jonathan Neuschäfer 2bbf63264a powerpc/mm/32: Use page_is_ram to check for RAM
On systems where there is MMIO space between different blocks of RAM in
the physical address space, __ioremap_caller did not allow mapping these
MMIO areas, because they were below the end RAM and thus considered RAM
as well.  Use the memblock-based page_is_ram function, which returns
false for such MMIO holes.

v2:
  Keep the check for p < virt_to_phys(high_memory). On 32-bit systems
  with high memory (memory above physical address 4GiB), the high memory
  is expected to be available though ioremap. The high_memory variable
  marks the end of low memory; comparing against it means that only
  ioremap requests for low RAM will be denied.
  Reported by Michael Ellerman.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:43 +11:00
Jonathan Neuschäfer f65e67c7e3 powerpc/mm: Use memblock API for PPC32 page_is_ram
To support accurate checking for different blocks of memory on PPC32,
use the same memblock-based approach that's already used on PPC64 also
on PPC32.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:42 +11:00
Jonathan Neuschäfer 2615c93e5f powerpc/mm: Simplify page_is_ram by using memblock_is_memory
Instead of open-coding the search in page_is_ram, call memblock_is_memory.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:42 +11:00
Jonathan Neuschäfer 041413b88d powerpc/wii.dts: Add drive slot LED
The Wii has a blue LED in the disk drive slot, which is controlled via a
GPIO line. Add this LED to wii.dts, and mark it as a panic-indicator.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:41 +11:00
Jonathan Neuschäfer 80873a0b3a powerpc/wii.dts: Add GPIO line names
These are the GPIO line names on a Nintendo Wii, as documented in:
https://wiibrew.org/wiki/Hardware/Hollywood_GPIOs

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:40 +11:00
Jonathan Neuschäfer 9693d5709f powerpc/wii.dts: Add ngpios property
The Hollywood GPIO controller supports 32 GPIOs, but on the Wii, only 24
are used.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:40 +11:00
Jonathan Neuschäfer 9cbaaec1cf powerpc/wii: Explicitly configure GPIO owner for poweroff pin
The Hollywood chipset's GPIO controller has two sets of registers: One
for access by the PowerPC CPU, and one for access by the ARM coprocessor
(but both are accessible from the PPC because the memory firewall
(AHBPROT) is usually disabled when booting Linux, today).

The wii_power_off function currently assumes that the poweroff GPIO pin
is configured for use via the ARM side, but the upcoming GPIO driver
configures all pins for use via the PPC side, breaking poweroff.

Configure the owner register explicitly in wii_power_off to make
wii_power_off work with and without the new GPIO driver.

I think the Wii can be switched to the generic gpio-poweroff driver,
after the GPIO driver is merged.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:39 +11:00
Jonathan Neuschäfer 7ab96c0a08 powerpc/wii: Probe the whole devicetree
Previously, wii_device_probe would only initialize devices under the
/hollywood node. After this patch, platform devices placed outside of
/hollywood will also be initialized.

The intended usecase for this are devices located outside of the
Hollywood chip, such as GPIO LEDs and GPIO buttons.

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:39 +11:00
Michael Ellerman 1d0afc0d5a powerpc/64e: Fix oops due to deferral of paca allocation
On 64-bit Book3E systems, in setup_tlb_core_data() we reference other
CPUs pacas. But in commit 59f577743d ("powerpc/64: Defer paca
allocation until memory topology is discovered") the allocation of
non-boot-CPU pacas was deferred until later in boot.

This leads to an oops:

  CPU maps initialized for 1 thread per core
  Unable to handle kernel paging request for data at address 0x8888888888888918
  Faulting instruction address: 0xc000000000e2f0d0
  Oops: Kernel access of bad area, sig: 11 [#1]
  NIP .setup_tlb_core_data+0xdc/0x160
  Call Trace:
    .setup_tlb_core_data+0x5c/0x160 (unreliable)
    .setup_arch+0x80/0x348
    .start_kernel+0x7c/0x598
    start_here_common+0x1c/0x40

Luckily setup_tlb_core_data() is called immediately prior to
smp_setup_pacas(). So simply switching their order is sufficient to
fix the oops and seems unlikely to have any other unwanted side
effects.

Fixes: 59f577743d ("powerpc/64: Defer paca allocation until memory topology is discovered")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:38 +11:00
Aneesh Kumar K.V ca9a16c3bc powerpc/kvm: Fix guest boot failure on Power9 since DAWR changes
SLOF checks for 'sc 1' (hypercall) support by issuing a hcall with
H_SET_DABR. Since the recent commit e8ebedbf31 ("KVM: PPC: Book3S
HV: Return error from h_set_dabr() on POWER9") changed H_SET_DABR to
return H_UNSUPPORTED on Power9, we see guest boot failures, the
symptom is the boot seems to just stop in SLOF, eg:

  SLOF ***************************************************************
  QEMU Starting
   Build Date = Sep 24 2017 12:23:07
   FW Version = buildd@ release 20170724
  <no further output>

SLOF can cope if H_SET_DABR returns H_HARDWARE. So wwitch the return
value to H_HARDWARE instead of H_UNSUPPORTED so that we don't break
the guest boot.

That does mean we return a different error to PowerVM in this case,
but that's probably not a big concern.

Fixes: e8ebedbf31 ("KVM: PPC: Book3S HV: Return error from h_set_dabr() on POWER9")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-01 00:47:13 +11:00
Michael Ellerman f437c51748 Merge branch 'topic/paca' into next
Bring in yet another series that touches KVM code, and might need to
be merged into the kvm-ppc branch to resolve conflicts.

This required some changes in pnv_power9_force_smt4_catch/release()
due to the paca array becomming an array of pointers.
2018-03-31 09:09:36 +11:00
Aneesh Kumar K.V 872a100a49 powerpc/mm/hash: Don't memset pgd table if not needed
We need to zero-out pgd table only if we share the slab cache with
pud/pmd level caches. With the support of 4PB, we don't share the slab
cache anymore. Instead of removing the code completely hide it within
an #ifdef. We don't need to do this with any other page table level,
because they all allocate table of double the size and we take of
initializing the first half corrrectly during page table zap.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Consolidate multiple #if / #ifdef into one]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:39 +11:00
Aneesh Kumar K.V c2b4d8b741 powerpc/mm/hash64: Increase the VA range
This patch increases the max virtual (effective) address value to 4PB.
With 4K page size config we continue to limit ourself to 64TB.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Keep the H_PGTABLE_RANGE test, update it to work]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:38 +11:00
Aneesh Kumar K.V f384796c40 powerpc/mm: Add support for handling > 512TB address in SLB miss
For addresses above 512TB we allocate additional mmu contexts. To make
it all easy, addresses above 512TB are handled with IR/DR=1 and with
stack frame setup.

The mmu_context_t is also updated to track the new extended_ids. To
support upto 4PB we need a total 8 contexts.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Minor formatting tweaks and comment wording, switch BUG to WARN
      in get_ea_context().]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:38 +11:00
Aneesh Kumar K.V 0dea04b288 powerpc/mm/slice: Consolidate return path in slice_get_unmapped_area()
In a following patch, on finding a free area we will need to do
allocatinon of extra contexts as needed. Consolidating the return path
for slice_get_unmapped_area() will make that easier.

Split into a separate patch to make review easy.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:37 +11:00
Aneesh Kumar K.V 1a2f778970 powerpc/mm/keys: Move pte bits to correct headers
Memory keys are supported only with hash translation mode. Instead of
using #ifdef in generic code move the key related pte bits to
respective headers

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:36 +11:00
Frederic Barrat 16b19f1a03 powerpc/xive: Fix wrong xmon output caused by typo
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:36 +11:00
Nicholas Piggin 0bfdf59890 powerpc/64: Fix smp_wmb barrier definition use use lwsync consistently
asm/barrier.h is not always included after asm/synch.h, which meant
it was missing __SUBARCH_HAS_LWSYNC, so in some files smp_wmb() would
be eieio when it should be lwsync. kernel/time/hrtimer.c is one case.

__SUBARCH_HAS_LWSYNC is only used in one place, so just fold it in
to where it's used. Previously with my small simulator config, 377
instances of eieio in the tree. After this patch there are 55.

Fixes: 46d075be58 ("powerpc: Optimise smp_wmb")
Cc: stable@vger.kernel.org # v2.6.29+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:34 +11:00
Wei Yongjun 9a2c1d31e6 powerpc/4xx: Fix error return code in ppc4xx_msi_probe()
Fix to return a negative error code from the error handling
case instead of 0, as done elsewhere in this function.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
[mpe: Add missing ';' to make it compile]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:34 +11:00
Ram Pai f208638680 powerpc/mm: Fix thread_pkey_regs_init()
thread_pkey_regs_init() initializes the pkey related registers
instead of initializing the fields in the task structures.  Fortunately
those key related registers are re-set to zero when the task
gets scheduled on the cpu. However its good to fix this glaringly
visible error.

Fixes: 06bb53b338 ("powerpc: store and restore the pkey state across context switches")
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:33 +11:00
Naveen N. Rao e6e133c47e powerpc/kprobes: Fix call trace due to incorrect preempt count
Michael Ellerman reported the following call trace when running
ftracetest:

  BUG: using __this_cpu_write() in preemptible [00000000] code: ftracetest/6178
  caller is opt_pre_handler+0xc4/0x110
  CPU: 1 PID: 6178 Comm: ftracetest Not tainted 4.15.0-rc7-gcc6x-gb2cd1df #1
  Call Trace:
  [c0000000f9ec39c0] [c000000000ac4304] dump_stack+0xb4/0x100 (unreliable)
  [c0000000f9ec3a00] [c00000000061159c] check_preemption_disabled+0x15c/0x170
  [c0000000f9ec3a90] [c000000000217e84] opt_pre_handler+0xc4/0x110
  [c0000000f9ec3af0] [c00000000004cf68] optimized_callback+0x148/0x170
  [c0000000f9ec3b40] [c00000000004d954] optinsn_slot+0xec/0x10000
  [c0000000f9ec3e30] [c00000000004bae0] kretprobe_trampoline+0x0/0x10

This is showing up since OPTPROBES is now enabled with CONFIG_PREEMPT.

trampoline_probe_handler() considers itself to be a special kprobe
handler for kretprobes. In doing so, it expects to be called from
kprobe_handler() on a trap, and re-enables preemption before returning a
non-zero return value so as to suppress any subsequent processing of the
trap by the kprobe_handler().

However, with optprobes, we don't deal with special handlers (we ignore
the return code) and just try to re-enable preemption causing the above
trace.

To address this, modify trampoline_probe_handler() to not be special.
The only additional processing done in kprobe_handler() is to emulate
the instruction (in this case, a 'nop'). We adjust the value of
regs->nip for the purpose and delegate the job of re-enabling
preemption and resetting current kprobe to the probe handlers
(kprobe_handler() or optimized_callback()).

Fixes: 8a2d71a3f2 ("powerpc/kprobes: Disable preemption before invoking probe handler for optprobes")
Cc: stable@vger.kernel.org # v4.15+
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:33 +11:00
Nicholas Piggin 741de61766 powerpc/powernv: Handle unknown OPAL errors in opal_nvram_write()
opal_nvram_write currently just assumes success if it encounters an
error other than OPAL_BUSY or OPAL_BUSY_EVENT. Have it return -EIO
on other errors instead.

Fixes: 628daa8d5a ("powerpc/powernv: Add RTC and NVRAM support plus RTAS fallbacks")
Cc: stable@vger.kernel.org # v3.2+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Acked-by: Stewart Smith <stewart@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:32 +11:00
Mauricio Faria de Oliveira 0f9bdfe3c7 powerpc/pseries: Fix clearing of security feature flags
The H_CPU_BEHAV_* flags should be checked for in the 'behaviour' field
of 'struct h_cpu_char_result' -- 'character' is for H_CPU_CHAR_*
flags.

Found by playing around with QEMU's implementation of the hypercall:

  H_CPU_CHAR=0xf000000000000000
  H_CPU_BEHAV=0x0000000000000000

  This clears H_CPU_BEHAV_FAVOUR_SECURITY and H_CPU_BEHAV_L1D_FLUSH_PR
  so pseries_setup_rfi_flush() disables 'rfi_flush'; and it also
  clears H_CPU_CHAR_L1D_THREAD_PRIV flag. So there is no RFI flush
  mitigation at all for cpu_show_meltdown() to report; but currently
  it does:

  Original kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/meltdown
    Mitigation: RFI Flush

  Patched kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/meltdown
    Not affected

  H_CPU_CHAR=0x0000000000000000
  H_CPU_BEHAV=0xf000000000000000

  This sets H_CPU_BEHAV_BNDS_CHK_SPEC_BAR so cpu_show_spectre_v1() should
  report vulnerable; but currently it doesn't:

  Original kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/spectre_v1
    Not affected

  Patched kernel:

    # cat /sys/devices/system/cpu/vulnerabilities/spectre_v1
    Vulnerable

Brown-paper-bag-by: Michael Ellerman <mpe@ellerman.id.au>
Fixes: f636c14790 ("powerpc/pseries: Set or clear security feature flags")
Signed-off-by: Mauricio Faria de Oliveira <mauricfo@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:31 +11:00
Nicholas Piggin 29ab6c4708 powerpc/mm: Pass node id into create_section_mapping
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Move __map_kernel_page_nid() inside #ifdef SPARSEMEM_VMEMMAP]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:07:10 +11:00
Nicholas Piggin 2ad452ffaa powerpc/64s/radix: Allocate kernel page tables node-local if possible
Try to allocate kernel page tables for direct mapping and vmemmap
according to the node of the memory they will map. The node is not
available for the linear map in early boot, so use range allocation
to allocate the page tables from the region they map, which is
effectively node-local.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fix build error in radix__create_section_mapping()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:07:09 +11:00
Nicholas Piggin 0633dafcf8 powerpc/64s/radix: Split early page table mapping to its own function
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:07:09 +11:00
Nicholas Piggin f3865f9a71 powerpc/64: Allocate per-cpu stacks node-local if possible
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:07:08 +11:00
Nicholas Piggin 4890aea65a powerpc/64: Allocate pacas per node
Per-node allocations are possible on 64s with radix that does
not have the bolted SLB limitation.

Hash would be able to do the same if all CPUs had the bottom of
their node-local memory bolted as well. This is left as an
exercise for the reader.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add dummy definition of boot_cpuid for !SMP]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:06:44 +11:00
Nicholas Piggin 59f577743d powerpc/64: Defer paca allocation until memory topology is discovered
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Rename the dummy allocate_pacas() to fix 32-bit build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:28 +11:00
Nicholas Piggin 9f593f131e powerpc/setup: Add cpu_to_phys_id array
Build an array that finds hardware CPU number from logical CPU
number in firmware CPU discovery. Use that rather than setting
paca of other CPUs directly, to begin with. Subsequent patch will
not have pacas allocated at this point.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fix SMP=n build by adding #ifdef in arch_match_cpu_phys_id()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:27 +11:00
Nicholas Piggin c0abd0c745 powerpc/64: move default SPR recording
Move this into the early setup code, and don't iterate over CPU masks.
We don't want to call into sysfs so early from setup, and a future patch
won't initialize CPU masks by the time this is called.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fold in incremental fix from Nick for DSCR handling]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:26 +11:00
Nicholas Piggin 9bd9be006c powerpc/mm/numa: move numa topology discovery earlier
Split sparsemem initialisation from basic numa topology discovery.
Move the parsing earlier in boot, before pacas are allocated.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:26 +11:00
Nicholas Piggin 384e806784 powerpc/64s: Allocate slb_shadow structures individually
slb_shadow structures are avoided for radix environment.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:24 +11:00
Nicholas Piggin 499dcd4137 powerpc/64s: Allocate LPPACAs individually
We no longer allocate lppacas in an array, so this patch removes the
1kB static alignment for the structure, and enforces the PAPR
alignment requirements at allocation time. We can not reduce the 1kB
allocation size however, due to existing KVM hypervisors.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:24 +11:00
Nicholas Piggin d2e60075a3 powerpc/64: Use array of paca pointers and allocate pacas individually
Change the paca array into an array of pointers to pacas. Allocate
pacas individually.

This allows flexibility in where the PACAs are allocated. Future work
will allocate them node-local. Platforms that don't have address limits
on PACAs would be able to defer PACA allocations until later in boot
rather than allocate all possible ones up-front then freeing unused.

This is slightly more overhead (one additional indirection) for cross
CPU paca references, but those aren't too common.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:23 +11:00
Nicholas Piggin 8e0b634b13 powerpc/64s: Do not allocate lppaca if we are not virtualized
The "lppaca" is a structure registered with the hypervisor. This is
unnecessary when running on non-virtualised platforms. One field from
the lppaca (pmcregs_in_use) is also used by the host, so move the host
part out into the paca (lppaca field is still updated in
guest mode).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fix non-pseries build with some #ifdefs]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:22 +11:00
Michael Ellerman 0834d627fb powerpc/mpic: Check if cpu_possible() in mpic_physmask()
In mpic_physmask() we loop over all CPUs up to 32, then get the hard
SMP processor id of that CPU.

Currently that's possibly walking off the end of the paca array, but
in a future patch we will change the paca array to be an array of
pointers, and in that case we will get a NULL for missing CPUs and
oops. eg:

  Unable to handle kernel paging request for data at address 0x88888888888888b8
  Faulting instruction address: 0xc00000000004e380
  Oops: Kernel access of bad area, sig: 11 [#1]
  ...
  NIP .mpic_set_affinity+0x60/0x1a0
  LR  .irq_do_set_affinity+0x48/0x100

Fix it by checking the CPU is possible, this also fixes the code if
there are gaps in the CPU numbering which probably never happens on
mpic systems but who knows.

Debugged-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-30 23:34:22 +11:00
Michael Ellerman 95dff480bb Merge branch 'fixes' into next
Merge our fixes branch from the 4.16 cycle.

There were a number of important fixes merged, in particular some Power9
workarounds that we want in next for testing purposes. There's also been
some conflicting changes in the CPU features code which are best merged
and tested before going upstream.
2018-03-28 22:59:50 +11:00
Michael Ellerman c0b346729b Merge branch 'topic/ppc-kvm' into next
Merge the DAWR series, which touches arch code and KVM code and may need
to be merged into the kvm-ppc tree.
2018-03-27 23:55:49 +11:00