For low slice, max addr should be less than 4G. Without limiting this correctly
we will end up with a low slice mask which has 17th bit set. This is not
a problem with the current code because our low slice mask is of type u16. But
in later patch I am switching low slice mask to u64 type and having the 17bit
set result in wrong slice mask which in turn results in mmap failures.
Reviewed-by: NPaul Mackerras <paulus@ozlabs.org>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

BOOKE code is dead code as per the Kconfig details. So make it simpler
by enabling MM_SLICE only for book3s_64. The changes w.r.t nohash is just
removing deadcode. W.r.t ppc64, 4k without hugetlb will now enable MM_SLICE.
But that is good, because we reduce one extra variant which probably is not
getting tested much.
Reviewed-by: NPaul Mackerras <paulus@ozlabs.org>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

sam440ep_setup_rtc() is just called by machine_device_initcall() so make
it __init.
Signed-off-by: NYang Shi <yang.shi@windriver.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

With the unnecessary restriction to reserve memory for fadump at the
top of RAM forgone, update the documentation accordingly.
Signed-off-by: NHari Bathini <hbathini@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Currently, the area to preserve boot memory is reserved at the top of
RAM. This leaves fadump vulnerable to memory hot-remove operations. As
memory for fadump has to be reserved early in the boot process, fadump
can't be registered after a memory hot-remove operation. Though this
problem can't be eleminated completely, the impact can be minimized by
reserving memory at an offset closer to bottom of the RAM. The offset
for fadump memory reservation can be any value greater than fadump boot
memory size.
Signed-off-by: NHari Bathini <hbathini@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

OPAL returns OPAL_WRONG_STATE upon failing to provide sensor data due to
core sleeping/offline. Add a check in opal_get_sensor_data() for sensor
read failure with OPAL_WRONG_STATE return code and return -EIO.
Signed-off-by: NVipin K Parashar <vipin@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

For the current task, the kernel stack would only tell the last time the
process was rescheduled, if ever. Use the current stack pointer for the
current task.

Otherwise, every once in a while, the stacktrace printed when reading
/proc/self/stack would look like the process is running in userspace,
while it's not, which some may consider as a bug.

This is also consistent with some other architectures, like x86 and arm,
at least.
Signed-off-by: NThadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

cpu_ready_for_interrupts() is called after feature patching, so there's
no need to use early_cpu_has_feature().
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The config option for the POWER8 crc32c recently changed from
CONFIG_CRYPT_CRC32C_VPMSUM to CONFIG_CRYPTO_CRC32C_VPMSUM. Update
the configs.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Most people use perf these days, so save about 31kB by making oprofile
a module.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

It turns out cloud-config uses ISO9660 filesystems to inject
configuration data into cloud images. The cloud-config failures when
ISO9660_FS is not enabled are cryptic, and building it in makes
mainline testing easier, so re-enable it.
Signed-off-by: NAnton Blanchard <anton@samba.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

POWER9 adds form 1 scoms. The form of the indirection is specified in
the top nibble of the scom address.

Currently we do some (ugly) bit mangling so that we can fit a 64 bit
scom address into the debugfs interface. The current code only shifts
the top bit (indirect bit).

This patch changes it to shift the whole top nibble so that the form
of the indirection is also shifted.

This patch is backwards compatible with older scoms.

(This change isn't required in the arch/powerpc/platforms/powernv/opal-prd.c
scom interface as it passes the whole 64bit scom address without any bit
mangling)
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Currently the code to perform an OPAL call is duplicated between the
normal path and path taken when tracepoints are enabled. There's no
real need for this and combining them makes opal_tracepoint_entry
considerably easier to understand.
Signed-off-by: NOliver O'Halloran <oohall@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Currently the xmon debugger is set only via kernel boot command-line.
It's disabled by default, and can be enabled with "xmon=on" on the
command-line. Also, xmon may be accessed via sysrq mechanism.
But we cannot enable/disable xmon in runtime, it needs kernel reload.

This patch introduces a debugfs entry for xmon, allowing user to query
its current state and change it if desired. Basically, the "xmon" file
to read from/write to is under the debugfs mount point, on powerpc
directory. It's a simple attribute, value 0 meaning xmon is disabled
and value 1 the opposite. Writing these states to the file will take
immediate effect in the debugger.
Signed-off-by: NGuilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The xmon parameter nobt was added long time ago, by commit 26c8af5f
("[POWERPC] print backtrace when entering xmon"). The problem that time
was that during a crash in a machine with USB keyboard, xmon wouldn't
respond to commands from the keyboard, so printing the backtrace wouldn't
be possible.

Idea then was to show automatically the backtrace on xmon crash for the
first time it's invoked (if it recovers, next time xmon won't show
backtrace automatically). The nobt parameter was added _only_ to prevent
this automatic trace show. Seems long time ago USB keyboards didn't work
that well!

We don't need this parameter anymore, the feature of auto showing the
backtrace is interesting (imagine a case of auto-reboot script),
so this patch extends the functionality, by always showing the backtrace
automatically when xmon is invoked; it removes the nobt parameter too.

Also, this patch fixes __initdata placement on xmon_early and replaces
__initcall() with modern device_initcall() on sysrq handler.
Signed-off-by: NGuilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Once xmon is triggered by sysrq-x, it is enabled always afterwards even
if it is disabled during boot. This will cause a system reset interrupt
fail to dump. So keep xmon in its original state after exit.

We have several ways to set xmon on or off.
1) by a build config CONFIG_XMON_DEFAULT.
2) by a boot cmdline with xmon or xmon=early or xmon=on to enable xmon
and xmon=off to disable xmon. This value will override that in step 1.
3) by a debugfs interface, as proposed in this patchset.
And this value can override those in step 1 and 2.
Signed-off-by: NPan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Signed-off-by: NGuilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

POWER8 uses bit 36 in SRR1 like POWER9 for i-side machine checks, and
contains several conditions for link timeouts that are not currently
handled.
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Move the handling (corrective action) of machine checks to the table
based evaluation.

This changes P7 and P8 ERAT flushing from using SLB flush to using ERAT
flush.
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Have machine types define i-side and d-side tables to describe their
machine check encodings, and match entries to evaluate (for reporting)
machine checks.

Functionality is mostly unchanged (tested with a userspace harness), but
it does make a change in that it no longer records DAR as the effective
address for those errors where it is specified to be invalid (which is a
reporting change only).
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Use the flush function introduced with the POWER9 machine check handler
for POWER7 and 8, rather than open coding it multiple times in callers.

There is a specific ERAT flush type introduced for POWER9, but the
POWER7-8 ERAT errors continue to do SLB flushing (which also flushes
ERAT), so as not to introduce functional changes with this cleanup
patch.
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Print the faulting address of the machine check that may help with
debugging. The effective address reported can be a target memory address
rather than the faulting instruction address.

Fix up a dangling bracket while here.
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

We'd like to eventually remove NO_IRQ on powerpc, so remove usages of it
from electra_cf.c which is a powerpc-only driver.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Submitters of device tree binding documentation may forget to CC
the subsystem maintainer if this is missing.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Add declarations for:
  - __mfdcr, __mtdcr (if CONFIG_PPC_DCR_NATIVE=y; through <asm/dcr.h>)
  - switch_mmu_context (if CONFIG_PPC_BOOK3S_64=n; through <asm/mmu_context.h>)
Signed-off-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The symbols exported for use by MOL/rtlinux aren't getting CRCs and I
was about to fix that. But MOL is dead upstream, and the latest work on
it was to make it use KVM instead of its own kernel module. So remove
them instead.
Signed-off-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Since the fault retry is now handled earlier, we can release the
mmap_sem lock earlier too and remove later unlocking previously done in
mm_fault_error().
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NLaurent Dufour <ldufour@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

In do_page_fault() if handle_mm_fault() returns VM_FAULT_RETRY, retry
the page fault handling before anything else.

This would simplify the handling of the mmap_sem lock in this part of
the code.
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NLaurent Dufour <ldufour@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Move mmap_sem releasing in the do_sigbus()'s unique caller : mm_fault_error()

No functional changes.
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NLaurent Dufour <ldufour@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

PNV_IODA_PE_DEV is only used for NPU devices (emulated PCI bridges
representing NVLink). These are added to IOMMU groups with corresponding
NVIDIA devices after all non-NPU PEs are setup; a special helper -
pnv_pci_ioda_setup_iommu_api() - handles this in pnv_pci_ioda_fixup().

The pnv_pci_ioda2_setup_dma_pe() helper sets up DMA for a PE. It is called
for VFs (so it does not handle NPU case) and PCI bridges but only
IODA1 and IODA2 types. An NPU bridge has its own type id (PNV_PHB_NPU)
so pnv_pci_ioda2_setup_dma_pe() cannot be called on NPU and therefore
(pe->flags & PNV_IODA_PE_DEV) is always "false".

This removes not used iommu_add_device(). This should not cause any
behavioral change.
Signed-off-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The iommu_table_ops callbacks are declared CPU endian as they take and
return "unsigned long"; underlying hardware tables are big-endian.

However get() was missing be64_to_cpu(), this adds the missing conversion.

The only caller of this is crash dump at arch/powerpc/kernel/iommu.c,
iommu_table_clear() which only compares TCE to zero so this change
should not cause behavioral change.
Signed-off-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: NDavid Gibson <david@gibson.dropbear.id.au>
Acked-by: NGavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Sparse emits a warning: symbol 'prepare_ftrace_return' was not
declared. Should it be static? prepare_ftrace_return() is called from
assembler and should not be static.

Add a prototype for it to asm-prototypes.h and include that in ftrace.c.
Signed-off-by: NTobin C. Harding <me@tobin.cc>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Sparse emits two symbol not declared warnings for swsusp.c. The two
functions, save_processor_state() and restore_processor_state() are
declared already in suspend.h, so include it.
Signed-off-by: NTobin C. Harding <me@tobin.cc>
Reviewed-by: NDaniel Axtens <dja@axtens.net>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

struct hcall_stats is only used in hvCall_inst.c, so move it there.
Signed-off-by: NTobin C. Harding <me@tobin.cc>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This is a very basic test of the new cache shape AUXV entries. All it
does at the moment is look for the entries and error out if we don't
find all the ones we expect. Primarily intended for folks bringing up a
new chip to check that the cache info is making it all the way to
userspace correctly.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Refactor the AUXV routines so they are more composable. In a future test
we want to look for many AUXV entries and we don't want to have to read
/proc/self/auxv each time.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Fix an assembler error when the THREAD_SIZE is greater than 16k.
Signed-off-by: NHamish Martin <hamish.martin@alliedtelesis.co.nz>
Reviewed-by: NChris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Shift the logic for defining THREAD_SHIFT logic to Kconfig in order to
allow override by users.
Signed-off-by: NHamish Martin <hamish.martin@alliedtelesis.co.nz>
Reviewed-by: NChris Packham <chris.packham@alliedtelesis.co.nz>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

This BUG_ON() triggered for me once at shutdown, and I don't see a
reason for the check.  The code correctly checks whether the swap slot
cache is usable or not, so an uninitialized swap slot cache is not
actually problematic afaik.

I've temporarily just switched the BUG_ON() to a WARN_ON_ONCE(), since
I'm not sure why that seemingly pointless check was there.  I suspect
the real fix is to just remove it entirely, but for now we'll warn about
it but not bring the machine down.

Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>