When we take an SLB multi-hit on bare metal, we see both the multi-hit
and parity error bits set in DSISR. The user manuals indicates this is
expected to always happen on Power8, whereas on Power9 it says a
multi-hit will "usually" also cause a parity error.

We decide what to do based on the various error tables in mce_power.c,
and because we process them in order and only report the first, we
currently always report a parity error but not the multi-hit, eg:

  Severe Machine check interrupt [Recovered]
    Initiator: CPU
    Error type: SLB [Parity]
      Effective address: c000000ffffd4300

Although this is correct, it leaves the user wondering why they got a
parity error. It would be clearer instead if we reported the
multi-hit because that is more likely to be simply a software bug,
whereas a true parity error is possibly an indication of a bad core.

We can do that simply by reordering the error tables so that multi-hit
appears before parity. That doesn't affect the error recovery at all,
because we flush the SLB either way.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

This was added to support an early version of Power8 that did not have
working doorbells. These machines were not publicly available, and all of
the internal users have long since upgraded.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Using 'at24' as fallback is now deprecated - use the full
'atmel,<model>' string.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Using compatible strings without the <manufacturer> part for at24 is
now deprecated. Use a correct 'atmel,<model>' value.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Using 'at' as the <manufacturer> part of the compatible string is now
deprecated. Use a correct string: 'atmel,<model>'.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

POWER9 does not support global pstate requests for the chip. So remove
the timer logic which slowly ramps down the global pstate in P9
platforms.
Signed-off-by: Shilpasri G Bhat <shilpa.bhat@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
[mpe: Drop NULL check before kfree(policy->driver_data)]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Enable kernel XZ compression option on BOOK3S_32. Tested on G4
PowerBook.
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
[mpe: Use one select under the PPC symbol guarded by if PPC_BOOK3S]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

In the quest to remove all stack VLA usage from the kernel[1], this
switches from an unchanging variable to a constant expression to
eliminate the VLA generation.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.comSigned-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The sketchy bypass uses 256M pages so add this page size as well.

This should cause no behavioral change but will be used later.

Fixes: 477afd6ea6 "powerpc/ioda: Use ibm,supported-tce-sizes for IOMMU page size mask"
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Memory reservation for crashkernel could fail if there are holes around
kdump kernel offset (128M). Fail gracefully in such cases and print an
error message.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Tested-by: David Gibson <dgibson@redhat.com>
Reviewed-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

In the quest to remove all stack VLA usage from the kernel[1], this
switches to using a stack size large enough for the saved routine and
adds a sanity check making sure the routine doesn't overflow into the
0x600 exception handler.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.comSigned-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

If a process exits without doing proper cleanup, there's a window
where an opencapi device can try to access the memory of the dying
process and may trigger a page fault. That's an expected scenario and
the ocxl driver holds a reference on the mm_struct of the process
until the opencapi device is notified of the process exiting.
However, if mm_users is already at 0, i.e. the address space of the
process has already been destroyed, the driver shouldn't try resolving
the page fault, as it will fail, but it can also try accessing already
freed data.

It is fixed by only calling the bottom half of the page fault handler
if mm_users is greater than 0 and get a reference on mm_users instead
of mm_count. Otherwise, we can safely return a translation fault to
the device, as its associated memory context is being removed. The
opencapi device will be properly cleaned up shortly after when closing
the file descriptors.

Fixes: 5ef3166e ("ocxl: Driver code for 'generic' opencapi devices")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Reviewed-By: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Fix two typos in the file header. Replacing the word 'priviledged'
by 'privileged' and 'exuecuted' by 'executed'.
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Gustavo Romero <gromero@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

There is a buffer overflow in dscr_inherit_test.c test. In main(), strncpy()'s
third argument is the length of the source, not the size of the destination
buffer, which makes strncpy() behaves like strcpy(), causing a buffer overflow
if argv[0] is bigger than LEN_MAX (100).

This patch maps 'prog' to the argv[0] memory region, removing the static
allocation and the LEN_MAX size restriction.
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Remove a few XSL/CX4 oddities which are no longer needed. A simple
revert of the initial commits was not possible (or not worth it) due
to the history of the code.
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Remove abandonned capi support for the Mellanox CX4.

This reverts commit a19bd79e.
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Remove abandonned capi support for the Mellanox CX4.

This reverts commit 4e56f858.
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Remove abandonned capi support for the Mellanox CX4.

This reverts commit 4361b034.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Remove abandonned capi support for the Mellanox CX4.

This reverts commit 317f5ef1.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Remove abandonned capi support for the Mellanox CX4.

This reverts commit b0b5e591.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Remove abandonned capi support for the Mellanox CX4.

This reverts commit 79384e4b.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Remove abandonned capi support for the Mellanox CX4.

This reverts commit cbce0917.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Remove abandonned capi support for the Mellanox CX4.

This reverts commit a2f67d5e.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Remove abandonned capi support for the Mellanox CX4.
The symbol 'cxl_set_translation_mode' is never called, so
ctx->real_mode is always false.

This reverts commit 7a0d85d3.
Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

debugfs doesn't support mmap(), so this code is never used.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

We use PHB in mode1 which uses bit 59 to select a correct DMA window.
However there is mode2 which uses bits 59:55 and allows up to 32 DMA
windows per a PE.

Even though documentation does not clearly specify that, it seems that
the actual hardware does not support bits 59:55 even in mode1, in other
words we can create a window as big as 1<<58 but DMA simply won't work.

This reduces the upper limit from 59 to 55 bits to let the userspace know
about the hardware limits.

Fixes: 7aafac11 "powerpc/powernv/ioda2: Gracefully fail if too many TCE levels requested"
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Signed-off-by: Michael Neuling <mikey@neuling.org>
Acked-by: Stewart Smith <stewart@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Signed-off-by: Michael Neuling <mikey@neuling.org>
Acked-by: Stewart Smith <stewart@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Commit 59f47eff ("powerpc/pci: Use of_irq_parse_and_map_pci() helper")
removed the 'oirq' variable, but kept memsetting it when the DEBUG macro is
defined.

When setting DEBUG macro for debugging purpose, the kernel fails to build since
'oirq' is not defined anymore.

This patch simply remove the debug block, since it does not seem to sense
now.

Fixes: 59f47eff ("powerpc/pci: Use of_irq_parse_and_map_pci() helper")
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

64-bit ELF v2 ABI specification for POWER describes, on section "General
Stack Frame Requirements", that the stack should use the following
instructions when compiled with backchain:

  mflr r0
  std  r0, 16(r1)
  stdu r1, -XX(r1)

Where XX is the frame size for that function, and this is the value
checkstack.pl will find the stack size for each function.

This patch also simplifies the entire Powerpc section, since just two
type of instructions are used, 'stdu' for 64 bits and 'stwu' for 32 bits
platform.
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The workaround has been removed. What stays is just code to find the
memory hole so the BATs can be configured properly in the function below.

Fixes: 57deb8fe ("powerpc/wii: Don't rely on the reserved memory hack")
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

get_monotonic_boottime() is deprecated, and may not be safe to call in
every context, as it has to read a hardware clocksource.

This changes xmon to print the time using ktime_get_coarse_boottime64()
instead, which avoids the old timespec type and the HW access.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Due to recent refactoring in EEH in:
commit b9fde58d ("powerpc/powernv: Rework EEH initialization on
powernv")
a misleading message was seen in the kernel message buffer:

[    0.108431] EEH: PowerNV platform initialized
[    0.589979] EEH: No capable adapters found

This happened due to the removal of the initialization delay for powernv
platform.

Even though the EEH infrastructure for the devices is eventually
initialized and still works just fine the eeh device probe step is
postponed in order to assure the PEs are created. Later
pnv_eeh_post_init does the probe devices job but at that point the
message was already shown right after eeh_init flow.

This patch introduces a new flag EEH_POSTPONED_PROBE to represent that
temporary state and avoid the message mentioned above and showing the
follow one instead:

[    0.107724] EEH: PowerNV platform initialized
[    4.844825] EEH: PCI Enhanced I/O Error Handling Enabled
Signed-off-by: Mauro S. M. Rodrigues <maurosr@linux.vnet.ibm.com>
Acked-by: Russell Currey <ruscur@russell.cc>
Tested-by: Venkat Rao B <vrbagal1@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Use new return type vm_fault_t for fault handler. For now, this is
just documenting that the function returns a VM_FAULT value rather
than an errno. Once all instances are converted, vm_fault_t will
become a distinct type.

Ref-> commit 1c8f4220 ("mm: change return type to vm_fault_t")

There is an existing bug when vm_insert_pfn() can return ENOMEM which
was ignored and VM_FAULT_NOPAGE returned as default. The new inline
vmf_insert_pfn() has removed this inefficiency by returning correct
vm_fault_ type.
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Pull btrfs fixes from David Sterba:
 "We have a few regression fixes for qgroup rescan status tracking and
  the vm_fault_t conversion that mixed up the error values"

* tag 'for-4.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix mount failure when qgroup rescan is in progress
  Btrfs: fix regression in btrfs_page_mkwrite() from vm_fault_t conversion
  btrfs: quota: Set rescan progress to (u64)-1 if we hit last leaf

Pull vfs fix from Al Viro:
 "Followup to procfs-seq_file series this window"

This fixes a memory leak by making sure that proc seq files release any
private data on close.  The 'proc_seq_open' has to be properly paired
with 'proc_seq_release' that releases the extra private data.

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  proc: add proc_seq_release

Pull staging/IIO fixes from Greg KH:
 "Here are a few small staging and IIO driver fixes for 4.18-rc3.

  Nothing major or big, all just fixes for reported problems since
  4.18-rc1. All of these have been in linux-next this week with no
  reported problems"

* tag 'staging-4.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: android: ion: Return an ERR_PTR in ion_map_kernel
  staging: comedi: quatech_daqp_cs: fix no-op loop daqp_ao_insn_write()
  iio: imu: inv_mpu6050: Fix probe() failure on older ACPI based machines
  iio: buffer: fix the function signature to match implementation
  iio: mma8452: Fix ignoring MMA8452_INT_DRDY
  iio: tsl2x7x/tsl2772: avoid potential division by zero
  iio: pressure: bmp280: fix relative humidity unit

Pull tty/serial fixes from Greg KH:
 "Here are five fixes for the tty core and some serial drivers.

  The tty core ones fix some security and other issues reported by the
  syzbot that I have taken too long in responding to (sorry Tetsuo!).

  The 8350 serial driver fix resolves an issue of devices that used to
  work properly stopping working as they shouldn't have been added to a
  blacklist.

  All of these have been in linux-next for a few days with no reported
  issues"

* tag 'tty-4.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  vt: prevent leaking uninitialized data to userspace via /dev/vcs*
  serdev: fix memleak on module unload
  serial: 8250_pci: Remove stalled entries in blacklist
  n_tty: Access echo_* variables carefully.
  n_tty: Fix stall at n_tty_receive_char_special().

Pull USB fixes from Greg KH:
 "Here is a number of USB gadget and other driver fixes for 4.18-rc3.

  There's a bunch of them here, most of them being gadget driver and
  xhci host controller fixes for reported issues (as normal), but there
  are also some new device ids, and some fixes for the typec code.

  There is an acpi core patch in here that was acked by the acpi
  maintainer as it is needed for the typec fixes in order to properly
  solve a problem in that driver.

  All of these have been in linux-next this week with no reported
  issues"

* tag 'usb-4.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (33 commits)
  usb: chipidea: host: fix disconnection detect issue
  usb: typec: tcpm: fix logbuffer index is wrong if _tcpm_log is re-entered
  typec: tcpm: Fix a msecs vs jiffies bug
  NFC: pn533: Fix wrong GFP flag usage
  usb: cdc_acm: Add quirk for Uniden UBC125 scanner
  staging/typec: fix tcpci_rt1711h build errors
  usb: typec: ucsi: Fix for incorrect status data issue
  usb: typec: ucsi: acpi: Workaround for cache mode issue
  acpi: Add helper for deactivating memory region
  usb: xhci: increase CRS timeout value
  usb: xhci: tegra: fix runtime PM error handling
  usb: xhci: remove the code build warning
  xhci: Fix kernel oops in trace_xhci_free_virt_device
  xhci: Fix perceived dead host due to runtime suspend race with event handler
  dwc2: gadget: Fix ISOC IN DDMA PID bitfield value calculation
  usb: gadget: dwc2: fix memory leak in gadget_init()
  usb: gadget: composite: fix delayed_status race condition when set_interface
  usb: dwc2: fix isoc split in transfer with no data
  usb: dwc2: alloc dma aligned buffer for isoc split in
  usb: dwc2: fix the incorrect bitmaps for the ports of multi_tt hub
  ...