Commit Graph

415 Commits

Author SHA1 Message Date
Linus Torvalds 5ad18b2e60 Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull force_sig() argument change from Eric Biederman:
 "A source of error over the years has been that force_sig has taken a
  task parameter when it is only safe to use force_sig with the current
  task.

  The force_sig function is built for delivering synchronous signals
  such as SIGSEGV where the userspace application caused a synchronous
  fault (such as a page fault) and the kernel responded with a signal.

  Because the name force_sig does not make this clear, and because the
  force_sig takes a task parameter the function force_sig has been
  abused for sending other kinds of signals over the years. Slowly those
  have been fixed when the oopses have been tracked down.

  This set of changes fixes the remaining abusers of force_sig and
  carefully rips out the task parameter from force_sig and friends
  making this kind of error almost impossible in the future"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits)
  signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus
  signal: Remove the signal number and task parameters from force_sig_info
  signal: Factor force_sig_info_to_task out of force_sig_info
  signal: Generate the siginfo in force_sig
  signal: Move the computation of force into send_signal and correct it.
  signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal
  signal: Remove the task parameter from force_sig_fault
  signal: Use force_sig_fault_to_task for the two calls that don't deliver to current
  signal: Explicitly call force_sig_fault on current
  signal/unicore32: Remove tsk parameter from __do_user_fault
  signal/arm: Remove tsk parameter from __do_user_fault
  signal/arm: Remove tsk parameter from ptrace_break
  signal/nds32: Remove tsk parameter from send_sigtrap
  signal/riscv: Remove tsk parameter from do_trap
  signal/sh: Remove tsk parameter from force_sig_info_fault
  signal/um: Remove task parameter from send_sigtrap
  signal/x86: Remove task parameter from send_sigtrap
  signal: Remove task parameter from force_sig_mceerr
  signal: Remove task parameter from force_sig
  signal: Remove task parameter from force_sigsegv
  ...
2019-07-08 21:48:15 -07:00
Michael Neuling a278e7ea60 powerpc: Fix compile issue with force DAWR
If you compile with KVM but without CONFIG_HAVE_HW_BREAKPOINT you fail
at linking with:
  arch/powerpc/kvm/book3s_hv_rmhandlers.o:(.text+0x708): undefined reference to `dawr_force_enable'

This was caused by commit c1fe190c06 ("powerpc: Add force enable of
DAWR on P9 option").

This moves a bunch of code around to fix this. It moves a lot of the
DAWR code in a new file and creates a new CONFIG_PPC_DAWR to enable
compiling it.

Fixes: c1fe190c06 ("powerpc: Add force enable of DAWR on P9 option")
Signed-off-by: Michael Neuling <mikey@neuling.org>
[mpe: Minor formatting in set_dawr()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-07-03 15:19:35 +10:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Eric W. Biederman 2e1661d267 signal: Remove the task parameter from force_sig_fault
As synchronous exceptions really only make sense against the current
task (otherwise how are you synchronous) remove the task parameter
from from force_sig_fault to make it explicit that is what is going
on.

The two known exceptions that deliver a synchronous exception to a
stopped ptraced task have already been changed to
force_sig_fault_to_task.

The callers have been changed with the following emacs regular expression
(with obvious variations on the architectures that take more arguments)
to avoid typos:

force_sig_fault[(]\([^,]+\)[,]\([^,]+\)[,]\([^,]+\)[,]\W+current[)]
->
force_sig_fault(\1,\2,\3)

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-29 09:31:43 -05:00
Nicholas Piggin e2b36d5917 powerpc/64: Don't trace code that runs with the soft irq mask unreconciled
"Reconciling" in terms of interrupt handling, is to bring the soft irq
mask state in to synch with the hardware, after an interrupt causes
MSR[EE] to be cleared (while the soft mask may be enabled, and hard
irqs not marked disabled).

General kernel code should not be called while unreconciled, because
local_irq_disable, etc. manipulations can cause surprising irq traces,
and it's fragile because the soft irq code does not really expect to
be called in this situation.

When exiting from an interrupt, MSR[EE] is cleared to prevent races,
but soft irq state is enabled for the returned-to context, so this is
now an unreconciled state. restore_math is called in this state, and
that can be ftraced, and the ftrace subsystem disables local irqs.

Mark restore_math and its callees as notrace. Restore a sanity check
in the soft irq code that had to be disabled for this case, by commit
4da1f79227 ("powerpc/64: Disable irq restore warning for now").

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:58:11 +10:00
Mathieu Malaterre a5ae043de7 powerpc/64s: Remove 'dummy_copy_buffer'
In commit 2bf1071a8d ("powerpc/64s: Remove POWER9 DD1 support") the
function __switch_to remove usage for 'dummy_copy_buffer'. Since it is
not used anywhere else, remove it completely.

This remove the following warning:
  arch/powerpc/kernel/process.c:1156:17: error: 'dummy_copy_buffer' defined but not used

Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-01 12:08:44 +10:00
Michael Ellerman bdc7c970bc Merge branch 'topic/ppc-kvm' into next
Merge our topic branch shared with KVM. In particular this includes the
rewrite of the idle code into C.
2019-04-30 22:52:03 +10:00
Michael Neuling c1fe190c06 powerpc: Add force enable of DAWR on P9 option
This adds a flag so that the DAWR can be enabled on P9 via:
  echo Y > /sys/kernel/debug/powerpc/dawr_enable_dangerous

The DAWR was previously force disabled on POWER9 in:
  9654153158 powerpc: Disable DAWR in the base POWER9 CPU features
Also see Documentation/powerpc/DAWR-POWER9.txt

This is a dangerous setting, USE AT YOUR OWN RISK.

Some users may not care about a bad user crashing their box
(ie. single user/desktop systems) and really want the DAWR.  This
allows them to force enable DAWR.

This flag can also be used to disable DAWR access. Once this is
cleared, all DAWR access should be cleared immediately and your
machine once again safe from crashing.

Userspace may get confused by toggling this. If DAWR is force
enabled/disabled between getting the number of breakpoints (via
PTRACE_GETHWDBGINFO) and setting the breakpoint, userspace will get an
inconsistent view of what's available. Similarly for guests.

For the DAWR to be enabled in a KVM guest, the DAWR needs to be force
enabled in the host AND the guest. For this reason, this won't work on
POWERVM as it doesn't allow the HCALL to work. Writes of 'Y' to the
dawr_enable_dangerous file will fail if the hypervisor doesn't support
writing the DAWR.

To double check the DAWR is working, run this kernel selftest:
  tools/testing/selftests/powerpc/ptrace/ptrace-hwbreak.c
Any errors/failures/skips mean something is wrong.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-20 22:20:45 +10:00
Aneesh Kumar K.V f89bd8ba83 powerpc/mm/radix: Don't do SLB preload when using the radix MMU
Add radix_enabled() check to avoid SLB preload with radix translation.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-20 22:02:26 +10:00
Christophe Leroy a7916a1de5 powerpc: regain entire stack space
thread_info is not anymore in the stack, so the entire stack
can now be used.

There is also no risk anymore of corrupting task_cpu(p) with a
stack overflow so the patch removes the test.

When doing this, an explicit test for NULL stack pointer is
needed in validate_sp() as it is not anymore implicitely covered
by the sizeof(thread_info) gap.

In the meantime, with the previous patch all pointers to the stacks
are not anymore pointers to thread_info so this patch changes them
to void*

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy ed1cd6deb0 powerpc: Activate CONFIG_THREAD_INFO_IN_TASK
This patch activates CONFIG_THREAD_INFO_IN_TASK which
moves the thread_info into task_struct.

Moving thread_info into task_struct has the following advantages:
  - It protects thread_info from corruption in the case of stack
    overflows.
  - Its address is harder to determine if stack addresses are leaked,
    making a number of attacks more difficult.

This has the following consequences:
  - thread_info is now located at the beginning of task_struct.
  - The 'cpu' field is now in task_struct, and only exists when
    CONFIG_SMP is active.
  - thread_info doesn't have anymore the 'task' field.

This patch:
  - Removes all recopy of thread_info struct when the stack changes.
  - Changes the CURRENT_THREAD_INFO() macro to point to current.
  - Selects CONFIG_THREAD_INFO_IN_TASK.
  - Modifies raw_smp_processor_id() to get ->cpu from current without
    including linux/sched.h to avoid circular inclusion and without
    including asm/asm-offsets.h to avoid symbol names duplication
    between ASM constants and C constants.
  - Modifies klp_init_thread_info() to take a task_struct pointer
    argument.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add task_stack.h to livepatch.h to fix build fails]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy 05b98791ec powerpc: Replace current_thread_info()->task with current
We have a few places that use current_thread_info()->task to access
current. This won't work with THREAD_INFO_IN_TASK so fix them now.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy 018cce33c5 powerpc: prep stack walkers for THREAD_INFO_IN_TASK
[text copied from commit 9bbd4c56b0
("arm64: prep stack walkers for THREAD_INFO_IN_TASK")]

When CONFIG_THREAD_INFO_IN_TASK is selected, task stacks may be freed
before a task is destroyed. To account for this, the stacks are
refcounted, and when manipulating the stack of another task, it is
necessary to get/put the stack to ensure it isn't freed and/or re-used
while we do so.

This patch reworks the powerpc stack walking code to account for this.
When CONFIG_THREAD_INFO_IN_TASK is not selected these perform no
refcounting, and this should only be a structural change that does not
affect behaviour.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Move try_get_task_stack() below tsk == NULL check in show_stack()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Mark Cave-Ayland fe1ef6bcdb powerpc: Fix 32-bit KVM-PR lockup and host crash with MacOS guest
Commit 8792468da5 "powerpc: Add the ability to save FPU without
giving it up" unexpectedly removed the MSR_FE0 and MSR_FE1 bits from
the bitmask used to update the MSR of the previous thread in
__giveup_fpu() causing a KVM-PR MacOS guest to lockup and panic the
host kernel.

Leaving FE0/1 enabled means unrelated processes might receive FPEs
when they're not expecting them and crash. In particular if this
happens to init the host will then panic.

eg (transcribed):
  qemu-system-ppc[837]: unhandled signal 8 at 12cc9ce4 nip 12cc9ce4 lr 12cc9ca4 code 0
  systemd[1]: unhandled signal 8 at 202f02e0 nip 202f02e0 lr 001003d4 code 0
  Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b

Reinstate these bits to the MSR bitmask to enable MacOS guests to run
under 32-bit KVM-PR once again without issue.

Fixes: 8792468da5 ("powerpc: Add the ability to save FPU without giving it up")
Cc: stable@vger.kernel.org # v4.6+
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:15 +11:00
Steven Rostedt (VMware) 0fad8bfef7 powerpc/frace: Use ftrace_graph_get_ret_stack() instead of curr_ret_stack
The structure of the ret_stack array on the task struct is going to
change, and accessing it directly via the curr_ret_stack index will no
longer give the ret_stack entry that holds the return address. To access
that, architectures must now use ftrace_graph_get_ret_stack() to get the
associated ret_stack that matches the saved return address.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@lists.ozlabs.org
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-22 08:20:45 -05:00
Linus Torvalds b69f9e17a5 powerpc fixes for 4.20 #2
Some things that I missed due to travel, or that came in late.
 
 Two fixes also going to stable:
 
  - A revert of a buggy change to the 8xx TLB miss handlers.
 
  - Our flushing of SPE (Signal Processing Engine) registers on fork was broken.
 
 Other changes:
 
  - A change to the KVM decrementer emulation to use proper APIs.
 
  - Some cleanups to the way we do code patching in the 8xx code.
 
  - Expose the maximum possible memory for the system in /proc/powerpc/lparcfg.
 
  - Merge some updates from Scott: "a couple device tree updates, and a fix for a
    missing prototype warning."
 
 A few other minor fixes and a handful of fixes for our selftests.
 
 Thanks to:
   Aravinda Prasad, Breno Leitao, Camelia Groza, Christophe Leroy, Felipe Rechia,
   Joel Stanley, Naveen N. Rao, Paul Mackerras, Scott Wood, Tyrel Datwyler.
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Merge tag 'powerpc-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "Some things that I missed due to travel, or that came in late.

  Two fixes also going to stable:

   - A revert of a buggy change to the 8xx TLB miss handlers.

   - Our flushing of SPE (Signal Processing Engine) registers on fork
     was broken.

  Other changes:

   - A change to the KVM decrementer emulation to use proper APIs.

   - Some cleanups to the way we do code patching in the 8xx code.

   - Expose the maximum possible memory for the system in
     /proc/powerpc/lparcfg.

   - Merge some updates from Scott: "a couple device tree updates, and a
     fix for a missing prototype warning"

  A few other minor fixes and a handful of fixes for our selftests.

  Thanks to: Aravinda Prasad, Breno Leitao, Camelia Groza, Christophe
  Leroy, Felipe Rechia, Joel Stanley, Naveen N. Rao, Paul Mackerras,
  Scott Wood, Tyrel Datwyler"

* tag 'powerpc-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (21 commits)
  selftests/powerpc: Fix compilation issue due to asm label
  selftests/powerpc/cache_shape: Fix out-of-tree build
  selftests/powerpc/switch_endian: Fix out-of-tree build
  selftests/powerpc/pmu: Link ebb tests with -no-pie
  selftests/powerpc/signal: Fix out-of-tree build
  selftests/powerpc/ptrace: Fix out-of-tree build
  powerpc/xmon: Relax frame size for clang
  selftests: powerpc: Fix warning for security subdir
  selftests/powerpc: Relax L1d miss targets for rfi_flush test
  powerpc/process: Fix flush_all_to_thread for SPE
  powerpc/pseries: add missing cpumask.h include file
  selftests/powerpc: Fix ptrace tm failure
  KVM: PPC: Use exported tb_to_ns() function in decrementer emulation
  powerpc/pseries: Export maximum memory value
  powerpc/8xx: Use patch_site for perf counters setup
  powerpc/8xx: Use patch_site for memory setup patching
  powerpc/code-patching: Add a helper to get the address of a patch_site
  Revert "powerpc/8xx: Use L1 entry APG to handle _PAGE_ACCESSED for CONFIG_SWAP"
  powerpc/8xx: add missing header in 8xx_mmu.c
  powerpc/8xx: Add DT node for using the SEC engine of the MPC885
  ...
2018-11-02 09:19:35 -07:00
Linus Torvalds 685f7e4f16 powerpc updates for 4.20
Notable changes:
 
  - A large series to rewrite our SLB miss handling, replacing a lot of fairly
    complicated asm with much fewer lines of C.
 
  - Following on from that, we now maintain a cache of SLB entries for each
    process and preload them on context switch. Leading to a 27% speedup for our
    context switch benchmark on Power9.
 
  - Improvements to our handling of SLB multi-hit errors. We now print more debug
    information when they occur, and try to continue running by flushing the SLB
    and reloading, rather than treating them as fatal.
 
  - Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9).
 
  - Add support for physical memory up to 2PB in the linear mapping on 64-bit
    Book3S. We only support up to 512TB as regular system memory, otherwise the
    percpu allocator runs out of vmalloc space.
 
  - Add stack protector support for 32 and 64-bit, with a per-task canary.
 
  - Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP.
 
  - Support recognising "big cores" on Power9, where two SMT4 cores are presented
    to us as a single SMT8 core.
 
  - A large series to cleanup some of our ioremap handling and PTE flags.
 
  - Add a driver for the PAPR SCM (storage class memory) interface, allowing
    guests to operate on SCM devices (acked by Dan).
 
  - Changes to our ftrace code to handle very large kernels, where we need to use
    a trampoline to get to ftrace_caller().
 
 Many other smaller enhancements and cleanups.
 
 Thanks to:
   Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton Blanchard, Aravinda
   Prasad, Bartlomiej Zolnierkiewicz, Benjamin Herrenschmidt, Breno Leitao,
   Cédric Le Goater, Christophe Leroy, Christophe Lombard, Dan Carpenter, Daniel
   Axtens, Finn Thain, Gautham R. Shenoy, Gustavo Romero, Haren Myneni, Hari
   Bathini, Jia Hongtao, Joel Stanley, John Allen, Laurent Dufour, Madhavan
   Srinivasan, Mahesh Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael
   Bringmann, Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan
   Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran,
   Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab, Rob Herring, Sam
   Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan Johnson, Stephen Rothwell,
   Stewart Smith, Suraj Jitindar Singh, Tyrel Datwyler, Vaibhav Jain, Vasant
   Hegde, YueHaibing, zhong jiang,
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Merge tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - A large series to rewrite our SLB miss handling, replacing a lot of
     fairly complicated asm with much fewer lines of C.

   - Following on from that, we now maintain a cache of SLB entries for
     each process and preload them on context switch. Leading to a 27%
     speedup for our context switch benchmark on Power9.

   - Improvements to our handling of SLB multi-hit errors. We now print
     more debug information when they occur, and try to continue running
     by flushing the SLB and reloading, rather than treating them as
     fatal.

   - Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9).

   - Add support for physical memory up to 2PB in the linear mapping on
     64-bit Book3S. We only support up to 512TB as regular system
     memory, otherwise the percpu allocator runs out of vmalloc space.

   - Add stack protector support for 32 and 64-bit, with a per-task
     canary.

   - Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP.

   - Support recognising "big cores" on Power9, where two SMT4 cores are
     presented to us as a single SMT8 core.

   - A large series to cleanup some of our ioremap handling and PTE
     flags.

   - Add a driver for the PAPR SCM (storage class memory) interface,
     allowing guests to operate on SCM devices (acked by Dan).

   - Changes to our ftrace code to handle very large kernels, where we
     need to use a trampoline to get to ftrace_caller().

  And many other smaller enhancements and cleanups.

  Thanks to: Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton
  Blanchard, Aravinda Prasad, Bartlomiej Zolnierkiewicz, Benjamin
  Herrenschmidt, Breno Leitao, Cédric Le Goater, Christophe Leroy,
  Christophe Lombard, Dan Carpenter, Daniel Axtens, Finn Thain, Gautham
  R. Shenoy, Gustavo Romero, Haren Myneni, Hari Bathini, Jia Hongtao,
  Joel Stanley, John Allen, Laurent Dufour, Madhavan Srinivasan, Mahesh
  Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael Bringmann,
  Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan
  Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver
  O'Halloran, Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab,
  Rob Herring, Sam Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan
  Johnson, Stephen Rothwell, Stewart Smith, Suraj Jitindar Singh, Tyrel
  Datwyler, Vaibhav Jain, Vasant Hegde, YueHaibing, zhong jiang"

* tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (221 commits)
  Revert "selftests/powerpc: Fix out-of-tree build errors"
  powerpc/msi: Fix compile error on mpc83xx
  powerpc: Fix stack protector crashes on CPU hotplug
  powerpc/traps: restore recoverability of machine_check interrupts
  powerpc/64/module: REL32 relocation range check
  powerpc/64s/radix: Fix radix__flush_tlb_collapsed_pmd double flushing pmd
  selftests/powerpc: Add a test of wild bctr
  powerpc/mm: Fix page table dump to work on Radix
  powerpc/mm/radix: Display if mappings are exec or not
  powerpc/mm/radix: Simplify split mapping logic
  powerpc/mm/radix: Remove the retry in the split mapping logic
  powerpc/mm/radix: Fix small page at boundary when splitting
  powerpc/mm/radix: Fix overuse of small pages in splitting logic
  powerpc/mm/radix: Fix off-by-one in split mapping logic
  powerpc/ftrace: Handle large kernel configs
  powerpc/mm: Fix WARN_ON with THP NUMA migration
  selftests/powerpc: Fix out-of-tree build errors
  powerpc/time: no steal_time when CONFIG_PPC_SPLPAR is not selected
  powerpc/time: Only set CONFIG_ARCH_HAS_SCALED_CPUTIME on PPC64
  powerpc/time: isolate scaled cputime accounting in dedicated functions.
  ...
2018-10-26 14:36:21 -07:00
Felipe Rechia e901378578 powerpc/process: Fix flush_all_to_thread for SPE
Fix a bug introduced by the creation of flush_all_to_thread() for
processors that have SPE (Signal Processing Engine) and use it to
compute floating-point operations.

>From userspace perspective, the problem was seen in attempts of
computing floating-point operations which should generate exceptions.
For example:

  fork();
  float x = 0.0 / 0.0;
  isnan(x);           // forked process returns False (should be True)

The operation above also should always cause the SPEFSCR FINV bit to
be set. However, the SPE floating-point exceptions were turned off
after a fork().

Kernel versions prior to the bug used flush_spe_to_thread(), which
first saves SPEFSCR register values in tsk->thread and then calls
giveup_spe(tsk).

After commit 579e633e76, the save_all() function was called first
to giveup_spe(), and then the SPEFSCR register values were saved in
tsk->thread. This would save the SPEFSCR register values after
disabling SPE for that thread, causing the bug described above.

Fixes 579e633e76 ("powerpc: create flush_all_to_thread()")
Signed-off-by: Felipe Rechia <felipe.rechia@datacom.com.br>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-26 21:58:58 +11:00
Linus Torvalds ba9f6f8954 Merge branch 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull siginfo updates from Eric Biederman:
 "I have been slowly sorting out siginfo and this is the culmination of
  that work.

  The primary result is in several ways the signal infrastructure has
  been made less error prone. The code has been updated so that manually
  specifying SEND_SIG_FORCED is never necessary. The conversion to the
  new siginfo sending functions is now complete, which makes it
  difficult to send a signal without filling in the proper siginfo
  fields.

  At the tail end of the patchset comes the optimization of decreasing
  the size of struct siginfo in the kernel from 128 bytes to about 48
  bytes on 64bit. The fundamental observation that enables this is by
  definition none of the known ways to use struct siginfo uses the extra
  bytes.

  This comes at the cost of a small user space observable difference.
  For the rare case of siginfo being injected into the kernel only what
  can be copied into kernel_siginfo is delivered to the destination, the
  rest of the bytes are set to 0. For cases where the signal and the
  si_code are known this is safe, because we know those bytes are not
  used. For cases where the signal and si_code combination is unknown
  the bits that won't fit into struct kernel_siginfo are tested to
  verify they are zero, and the send fails if they are not.

  I made an extensive search through userspace code and I could not find
  anything that would break because of the above change. If it turns out
  I did break something it will take just the revert of a single change
  to restore kernel_siginfo to the same size as userspace siginfo.

  Testing did reveal dependencies on preferring the signo passed to
  sigqueueinfo over si->signo, so bit the bullet and added the
  complexity necessary to handle that case.

  Testing also revealed bad things can happen if a negative signal
  number is passed into the system calls. Something no sane application
  will do but something a malicious program or a fuzzer might do. So I
  have fixed the code that performs the bounds checks to ensure negative
  signal numbers are handled"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (80 commits)
  signal: Guard against negative signal numbers in copy_siginfo_from_user32
  signal: Guard against negative signal numbers in copy_siginfo_from_user
  signal: In sigqueueinfo prefer sig not si_signo
  signal: Use a smaller struct siginfo in the kernel
  signal: Distinguish between kernel_siginfo and siginfo
  signal: Introduce copy_siginfo_from_user and use it's return value
  signal: Remove the need for __ARCH_SI_PREABLE_SIZE and SI_PAD_SIZE
  signal: Fail sigqueueinfo if si_signo != sig
  signal/sparc: Move EMT_TAGOVF into the generic siginfo.h
  signal/unicore32: Use force_sig_fault where appropriate
  signal/unicore32: Generate siginfo in ucs32_notify_die
  signal/unicore32: Use send_sig_fault where appropriate
  signal/arc: Use force_sig_fault where appropriate
  signal/arc: Push siginfo generation into unhandled_exception
  signal/ia64: Use force_sig_fault where appropriate
  signal/ia64: Use the force_sig(SIGSEGV,...) in ia64_rt_sigreturn
  signal/ia64: Use the generic force_sigsegv in setup_frame
  signal/arm/kvm: Use send_sig_mceerr
  signal/arm: Use send_sig_fault where appropriate
  signal/arm: Use force_sig_fault where appropriate
  ...
2018-10-24 11:22:39 +01:00
Nicholas Piggin 5434ae7462 powerpc/64s/hash: Add a SLB preload cache
When switching processes, currently all user SLBEs are cleared, and a
few (exec_base, pc, and stack) are preloaded. In trivial testing with
small apps, this tends to miss the heap and low 256MB segments, and it
will also miss commonly accessed segments on large memory workloads.

Add a simple round-robin preload cache that just inserts the last SLB
miss into the head of the cache and preloads those at context switch
time. Every 256 context switches, the oldest entry is removed from the
cache to shrink the cache and require fewer slbmte if they are unused.

Much more could go into this, including into the SLB entry reclaim
side to track some LRU information etc, which would require a study of
large memory workloads. But this is a simple thing we can do now that
is an obvious win for common workloads.

With the full series, process switching speed on the context_switch
benchmark on POWER9/hash (with kernel speculation security masures
disabled) increases from 140K/s to 178K/s (27%).

POWER8 does not change much (within 1%), it's unclear why it does not
see a big gain like POWER9.

Booting to busybox init with 256MB segments has SLB misses go down
from 945 to 69, and with 1T segments 900 to 21. These could almost all
be eliminated by preloading a bit more carefully with ELF binary
loading.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Nicholas Piggin 425d331462 powerpc/64s/hash: Provide arch_setup_exec() hooks for hash slice setup
This will be used by the SLB code in the next patch, but for now this
sets the slb_addr_limit to the correct size for 32-bit tasks.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Nicholas Piggin 4c2de74cc8 powerpc/64: Interrupts save PPR on stack rather than thread_struct
PPR is the odd register out when it comes to interrupt handling, it is
saved in current->thread.ppr while all others are saved on the stack.

The difficulty with this is that accessing thread.ppr can cause a SLB
fault, but the SLB fault handler implementation in C change had
assumed the normal exception entry handlers would not cause an SLB
fault.

Fix this by allocating room in the interrupt stack to save PPR.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14 18:04:09 +11:00
Christophe Leroy df13102f82 powerpc/process: Constify the number of insns printed by show instructions functions.
instructions_to_print var is assigned value 16 and there is no
way to change it.

This patch replaces it by a constant.

Reviewed-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-13 22:21:25 +11:00
Christophe Leroy fb2d9505c0 powerpc/process: Fix interleaved output in show_user_instructions()
When two processes crash at the same time, we sometimes encounter
interleaving in the middle of a line:

  init[1]: segfault (11) at 0 nip 0 lr 0 code 1
  init[1]: code: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
  init[74]: segfault (11) at 10a74 nip 1000c198 lr 100078c8 code 1 in sh[10000000+14000]
  XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
  init[1]: code: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
  init[74]: code: 90010024 bf61000c 91490a7c 3fa01002 3be00000 7d3e4b78 3bbd0c20 3b600000
  init[74]: code: 3b9d0040 7c7fe02e 2f830000 419e0028 <89230000> 2f890000 41be001c 4b7f6e79

This patch fixes it by preparing complete lines in a buffer and
printing it at once.

Fixes: 88b0fe1757 ("powerpc: Add show_user_instructions()")
Reviewed-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Use seq_buf_printf() not seq_buf_puts() which doesn't NULL terminate]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-13 22:21:25 +11:00
Christophe Leroy c9386bfd37 powerpc/process: Add missing include of stacktrace.h
As spotted by sparse:

  arch/powerpc/kernel/process.c:1302:6: warning: symbol 'show_user_instructions' was not declared. Should it be static?

Fixes: 88b0fe1757 ("powerpc: Add show_user_instructions()")
Reviewed-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-13 22:21:25 +11:00
Christophe Leroy 3b35bd48b8 powerpc/process: Fix sparse address space warnings
This patch fixes the following warnings, which are leftovers
from when __get_user() was replaced by probe_kernel_address().

arch/powerpc/kernel/process.c:1287:22: warning: incorrect type in argument 2 (different address spaces)
arch/powerpc/kernel/process.c:1287:22:    expected void const *src
arch/powerpc/kernel/process.c:1287:22:    got unsigned int [noderef] <asn:1>*<noident>
arch/powerpc/kernel/process.c:1319:21: warning: incorrect type in argument 2 (different address spaces)
arch/powerpc/kernel/process.c:1319:21:    expected void const *src
arch/powerpc/kernel/process.c:1319:21:    got unsigned int [noderef] <asn:1>*<noident>

Fixes: 7b051f665c ("powerpc: Use probe_kernel_address in show_instructions")
Reviewed-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-13 22:21:25 +11:00
Michael Ellerman 9b7e4d601b Merge branch 'fixes' into next
Merge our fixes branch. It has a few important fixes that are needed for
futher testing and also some commits that will conflict with content in
next.
2018-10-09 16:51:05 +11:00
Michael Ellerman a932ed3b71 powerpc: Don't print kernel instructions in show_user_instructions()
Recently we implemented show_user_instructions() which dumps the code
around the NIP when a user space process dies with an unhandled
signal. This was modelled on the x86 code, and we even went so far as
to implement the exact same bug, namely that if the user process
crashed with its NIP pointing into the kernel we will dump kernel text
to dmesg. eg:

  bad-bctr[2996]: segfault (11) at c000000000010000 nip c000000000010000 lr 12d0b0894 code 1
  bad-bctr[2996]: code: fbe10068 7cbe2b78 7c7f1b78 fb610048 38a10028 38810020 fb810050 7f8802a6
  bad-bctr[2996]: code: 3860001c f8010080 48242371 60000000 <7c7b1b79> 4082002c e8010080 eb610048

This was discovered on x86 by Jann Horn and fixed in commit
342db04ae7 ("x86/dumpstack: Don't dump kernel memory based on usermode RIP").

Fix it by checking the adjusted NIP value (pc) and number of
instructions against USER_DS, and bail if we fail the check, eg:

  bad-bctr[2969]: segfault (11) at c000000000010000 nip c000000000010000 lr 107930894 code 1
  bad-bctr[2969]: Bad NIP, not dumping instructions.

Fixes: 88b0fe1757 ("powerpc: Add show_user_instructions()")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-05 23:18:12 +10:00
Breno Leitao 5c784c8414 powerpc/tm: Remove msr_tm_active()
Currently msr_tm_active() is a wrapper around MSR_TM_ACTIVE() if
CONFIG_PPC_TRANSACTIONAL_MEM is set, or it is just a function that
returns false if CONFIG_PPC_TRANSACTIONAL_MEM is not set.

This function is not necessary, since MSR_TM_ACTIVE() just do the same and
could be used, removing the dualism and simplifying the code.

This patchset remove every instance of msr_tm_active() and replaced it
by MSR_TM_ACTIVE().

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-03 15:40:05 +10:00
Michael Ellerman 54be0b9c7c Revert "convert SLB miss handlers to C" and subsequent commits
This reverts commits:
  5e46e29e6a ("powerpc/64s/hash: convert SLB miss handlers to C")
  8fed04d0f6 ("powerpc/64s/hash: remove user SLB data from the paca")
  655deecf67 ("powerpc/64s/hash: SLB allocation status bitmaps")
  2e1626744e ("powerpc/64s/hash: provide arch_setup_exec hooks for hash slice setup")
  89ca4e126a ("powerpc/64s/hash: Add a SLB preload cache")

This series had a few bugs, and the fixes are not all trivial. So
revert most of it for now.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-03 15:32:49 +10:00
Eric W. Biederman f383d8b4ae signal/powerpc: Use force_sig_fault where appropriate
Reviewed-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-09-21 15:53:56 +02:00
Nicholas Piggin 89ca4e126a powerpc/64s/hash: Add a SLB preload cache
When switching processes, currently all user SLBEs are cleared, and a
few (exec_base, pc, and stack) are preloaded. In trivial testing with
small apps, this tends to miss the heap and low 256MB segments, and it
will also miss commonly accessed segments on large memory workloads.

Add a simple round-robin preload cache that just inserts the last SLB
miss into the head of the cache and preloads those at context switch
time. Every 256 context switches, the oldest entry is removed from the
cache to shrink the cache and require fewer slbmte if they are unused.

Much more could go into this, including into the SLB entry reclaim
side to track some LRU information etc, which would require a study of
large memory workloads. But this is a simple thing we can do now that
is an obvious win for common workloads.

With the full series, process switching speed on the context_switch
benchmark on POWER9/hash (with kernel speculation security masures
disabled) increases from 140K/s to 178K/s (27%).

POWER8 does not change much (within 1%), it's unclear why it does not
see a big gain like POWER9.

Booting to busybox init with 256MB segments has SLB misses go down
from 945 to 69, and with 1T segments 900 to 21. These could almost all
be eliminated by preloading a bit more carefully with ELF binary
loading.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 22:01:56 +10:00
Nicholas Piggin 2e1626744e powerpc/64s/hash: provide arch_setup_exec hooks for hash slice setup
This will be used by the SLB code in the next patch, but for now this
sets the slb_addr_limit to the correct size for 32-bit tasks.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19 22:01:56 +10:00
Murilo Opsfelder Araujo 88b0fe1757 powerpc: Add show_user_instructions()
show_user_instructions() is a slightly modified version of
show_instructions() that allows userspace instruction dump.

This will be useful within show_signal_msg() to dump userspace
instructions of the faulty location.

Here is a sample of what show_user_instructions() outputs:

  pandafault[10850]: code: 4bfffeec 4bfffee8 3c401002 38427f00 fbe1fff8 f821ffc1 7c3f0b78 3d22fffe
  pandafault[10850]: code: 392988d0 f93f0020 e93f0020 39400048 <99490000> 39200000 7d234b78 383f0040

The current->comm and current->pid printed can serve as a glue that
links the instructions dump to its originator, allowing messages to be
interleaved in the logs.

Signed-off-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-08-08 00:32:30 +10:00
Christophe Leroy b5ac51d747 powerpc: declare set_breakpoint() static
set_breakpoint() is only used in process.c so make it static

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-30 22:48:18 +10:00
Cyril Bur edd00b8307 powerpc/tm: Remove struct thread_info param from tm_reclaim_thread()
Since commit dc3106690b ("powerpc: tm: Always use fp_state and
vr_state to store live registers") tm_reclaim_thread() doesn't use the
parameter anymore, both callers have to bother getting it as they have
no need for a struct thread_info either.

Just remove it and adjust the callers.

Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-24 22:03:23 +10:00
Ram Pai c76662e825 powerpc/pkeys: Save the pkey registers before fork
When a thread forks the contents of AMR, IAMR, UAMOR registers in the
newly forked thread are not inherited.

Save the registers before forking, for content of those
registers to be automatically copied into the new thread.

Fixes: cf43d3b264 ("powerpc: Enable pkey subsystem")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-24 21:34:47 +10:00
Nicholas Piggin 2bf1071a8d powerpc/64s: Remove POWER9 DD1 support
POWER9 DD1 was never a product. It is no longer supported by upstream
firmware, and it is not effectively supported in Linux due to lack of
testing.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
[mpe: Remove arch_make_huge_pte() entirely]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-16 11:37:21 +10:00
Linus Torvalds c90fca951e powerpc updates for 4.18
Notable changes:
 
  - Support for split PMD page table lock on 64-bit Book3S (Power8/9).
 
  - Add support for HAVE_RELIABLE_STACKTRACE, so we properly support live
    patching again.
 
  - Add support for patching barrier_nospec in copy_from_user() and syscall entry.
 
  - A couple of fixes for our data breakpoints on Book3S.
 
  - A series from Nick optimising TLB/mm handling with the Radix MMU.
 
  - Numerous small cleanups to squash sparse/gcc warnings from Mathieu Malaterre.
 
  - Several series optimising various parts of the 32-bit code from Christophe Leroy.
 
  - Removal of support for two old machines, "SBC834xE" and "C2K" ("GEFanuc,C2K"),
    which is why the diffstat has so many deletions.
 
 And many other small improvements & fixes.
 
 There's a few out-of-area changes. Some minor ftrace changes OK'ed by Steve, and
 a fix to our powernv cpuidle driver. Then there's a series touching mm, x86 and
 fs/proc/task_mmu.c, which cleans up some details around pkey support. It was
 ack'ed/reviewed by Ingo & Dave and has been in next for several weeks.
 
 Thanks to:
   Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Al Viro, Andrew
   Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Arnd Bergmann, Balbir Singh,
   Cédric Le Goater, Christophe Leroy, Christophe Lombard, Colin Ian King, Dave
   Hansen, Fabio Estevam, Finn Thain, Frederic Barrat, Gautham R. Shenoy, Haren
   Myneni, Hari Bathini, Ingo Molnar, Jonathan Neuschäfer, Josh Poimboeuf,
   Kamalesh Babulal, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Greer, Mathieu
   Malaterre, Matthew Wilcox, Michael Neuling, Michal Suchanek, Naveen N. Rao,
   Nicholas Piggin, Nicolai Stange, Olof Johansson, Paul Gortmaker, Paul
   Mackerras, Peter Rosin, Pridhiviraj Paidipeddi, Ram Pai, Rashmica Gupta, Ravi
   Bangoria, Russell Currey, Sam Bobroff, Samuel Mendoza-Jonas, Segher
   Boessenkool, Shilpasri G Bhat, Simon Guo, Souptick Joarder, Stewart Smith,
   Thiago Jung Bauermann, Torsten Duwe, Vaibhav Jain, Wei Yongjun, Wolfram Sang,
   Yisheng Xie, YueHaibing.
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Merge tag 'powerpc-4.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - Support for split PMD page table lock on 64-bit Book3S (Power8/9).

   - Add support for HAVE_RELIABLE_STACKTRACE, so we properly support
     live patching again.

   - Add support for patching barrier_nospec in copy_from_user() and
     syscall entry.

   - A couple of fixes for our data breakpoints on Book3S.

   - A series from Nick optimising TLB/mm handling with the Radix MMU.

   - Numerous small cleanups to squash sparse/gcc warnings from Mathieu
     Malaterre.

   - Several series optimising various parts of the 32-bit code from
     Christophe Leroy.

   - Removal of support for two old machines, "SBC834xE" and "C2K"
     ("GEFanuc,C2K"), which is why the diffstat has so many deletions.

  And many other small improvements & fixes.

  There's a few out-of-area changes. Some minor ftrace changes OK'ed by
  Steve, and a fix to our powernv cpuidle driver. Then there's a series
  touching mm, x86 and fs/proc/task_mmu.c, which cleans up some details
  around pkey support. It was ack'ed/reviewed by Ingo & Dave and has
  been in next for several weeks.

  Thanks to: Akshay Adiga, Alastair D'Silva, Alexey Kardashevskiy, Al
  Viro, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Arnd
  Bergmann, Balbir Singh, Cédric Le Goater, Christophe Leroy, Christophe
  Lombard, Colin Ian King, Dave Hansen, Fabio Estevam, Finn Thain,
  Frederic Barrat, Gautham R. Shenoy, Haren Myneni, Hari Bathini, Ingo
  Molnar, Jonathan Neuschäfer, Josh Poimboeuf, Kamalesh Babulal,
  Madhavan Srinivasan, Mahesh Salgaonkar, Mark Greer, Mathieu Malaterre,
  Matthew Wilcox, Michael Neuling, Michal Suchanek, Naveen N. Rao,
  Nicholas Piggin, Nicolai Stange, Olof Johansson, Paul Gortmaker, Paul
  Mackerras, Peter Rosin, Pridhiviraj Paidipeddi, Ram Pai, Rashmica
  Gupta, Ravi Bangoria, Russell Currey, Sam Bobroff, Samuel
  Mendoza-Jonas, Segher Boessenkool, Shilpasri G Bhat, Simon Guo,
  Souptick Joarder, Stewart Smith, Thiago Jung Bauermann, Torsten Duwe,
  Vaibhav Jain, Wei Yongjun, Wolfram Sang, Yisheng Xie, YueHaibing"

* tag 'powerpc-4.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (251 commits)
  powerpc/64s/radix: Fix missing ptesync in flush_cache_vmap
  cpuidle: powernv: Fix promotion from snooze if next state disabled
  powerpc: fix build failure by disabling attribute-alias warning in pci_32
  ocxl: Fix missing unlock on error in afu_ioctl_enable_p9_wait()
  powerpc-opal: fix spelling mistake "Uniterrupted" -> "Uninterrupted"
  powerpc: fix spelling mistake: "Usupported" -> "Unsupported"
  powerpc/pkeys: Detach execute_only key on !PROT_EXEC
  powerpc/powernv: copy/paste - Mask SO bit in CR
  powerpc: Remove core support for Marvell mv64x60 hostbridges
  powerpc/boot: Remove core support for Marvell mv64x60 hostbridges
  powerpc/boot: Remove support for Marvell mv64x60 i2c controller
  powerpc/boot: Remove support for Marvell MPSC serial controller
  powerpc/embedded6xx: Remove C2K board support
  powerpc/lib: optimise PPC32 memcmp
  powerpc/lib: optimise 32 bits __clear_user()
  powerpc/time: inline arch_vtime_task_switch()
  powerpc/Makefile: set -mcpu=860 flag for the 8xx
  powerpc: Implement csum_ipv6_magic in assembly
  powerpc/32: Optimise __csum_partial()
  powerpc/lib: Adjust .balign inside string functions for PPC32
  ...
2018-06-07 10:23:33 -07:00
Alastair D'Silva 71cc64a85d powerpc: use task_pid_nr() for TID allocation
The current implementation of TID allocation, using a global IDR, may
result in an errant process starving the system of available TIDs.
Instead, use task_pid_nr(), as mentioned by the original author. The
scenario described which prevented it's use is not applicable, as
set_thread_tidr can only be called after the task struct has been
populated.

In the unlikely event that 2 threads share the TID and are waiting,
all potential outcomes have been determined safe.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:40:31 +10:00
Alastair D'Silva 3449f191ca powerpc: Use TIDR CPU feature to control TIDR allocation
Switch the use of TIDR on it's CPU feature, rather than assuming it
is available based on architecture.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:40:31 +10:00
Nicholas Piggin 3130a7bb6e powerpc/64: change softe to irqmask in show_regs and xmon
When the soft enabled flag was changed to a soft disable mask, xmon
and register dump code was not updated to reflect that, which is
confusing ('SOFTE: 1' previously meant interrupts were soft enabled,
currently it means the opposite, the general interrupt type has been
disabled).

Fix this by using the name irqmask, and printing it in hex.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:40:30 +10:00
Nicholas Piggin 3d3a6021dd powerpc/pseries: lparcfg calculate PURR on demand
For SPLPAR, lparcfg provides a sum of PURR registers for all CPUs.
Currently this is done by reading PURR in context switch and timer
interrupt, and storing that into a per-CPU variable. These are summed
to provide the value.

This does not work with all timer schemes (e.g., NO_HZ_FULL), and it
is sub-optimal for performance because it reads the PURR register on
every context switch, although that's been difficult to distinguish
from noise in the contxt_switch microbenchmark.

This patch implements the sum by calling a function on each CPU, to
read and add PURR values of each CPU.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:40:27 +10:00
Nicholas Piggin 36d632ea83 powerpc/64: remove start_tb and accum_tb from thread_struct
These fields are only written to.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-06-03 20:40:26 +10:00
Simon Guo d1c7211281 powerpc: Export msr_check_and_set() to modules
PR KVM will need to reuse msr_check_and_set().
This patch exports this API for reuse.

Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-24 16:03:24 +10:00
Eric W. Biederman 3eb0f5193b signal: Ensure every siginfo we send has all bits initialized
Call clear_siginfo to ensure every stack allocated siginfo is properly
initialized before being passed to the signal sending functions.

Note: It is not safe to depend on C initializers to initialize struct
siginfo on the stack because C is allowed to skip holes when
initializing a structure.

The initialization of struct siginfo in tracehook_report_syscall_exit
was moved from the helper user_single_step_siginfo into
tracehook_report_syscall_exit itself, to make it clear that the local
variable siginfo gets fully initialized.

In a few cases the scope of struct siginfo has been reduced to make it
clear that siginfo siginfo is not used on other paths in the function
in which it is declared.

Instances of using memset to initialize siginfo have been replaced
with calls clear_siginfo for clarity.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-04-25 10:40:51 -05:00
Nicholas Piggin 252988cbf0 powerpc: Don't write to DABR on >= Power8 if DAWR is disabled
flush_thread() calls __set_breakpoint() via set_debug_reg_defaults()
without checking ppc_breakpoint_available(). On Power8 or later CPUs
which have the DAWR feature disabled that will cause a write to the
DABR which is incorrect as those CPUs don't have a DABR.

Fix it two ways, by checking ppc_breakpoint_available() in
set_debug_reg_defaults(), and also by reworking __set_breakpoint() to
only write to DABR on Power7 or earlier.

Fixes: 9654153158 ("powerpc: Disable DAWR in the base POWER9 CPU features")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Rework the logic in __set_breakpoint()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-03 21:50:08 +10:00
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
Michael Neuling 404b27d66e powerpc: Add ppc_breakpoint_available()
Add ppc_breakpoint_available() to determine if a breakpoint is
available currently via the DAWR or DABR.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-27 23:52:43 +11:00
Mathieu Malaterre 1cdf039bf8 powerpc/kernel: Make function __giveup_fpu() static
__giveup_fpu() is never called outside process.c, so it can be static.
That also means we don't need an empty definition in switch_to.h

Signed-off-by: Mathieu Malaterre <malat@debian.org>
[mpe: Also drop the empty version, rewrite change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13 15:50:35 +11:00
Linus Torvalds 03f51d4efa powerpc updates for 4.16
Highlights:
 
  - Enable support for memory protection keys aka "pkeys" on Power7/8/9 when
    using the hash table MMU.
 
  - Extend our interrupt soft masking to support masking PMU interrupts as well
    as "normal" interrupts, and then use that to implement local_t for a ~4x
    speedup vs the current atomics-based implementation.
 
  - A new driver "ocxl" for "Open Coherent Accelerator Processor Interface
    (OpenCAPI)" devices.
 
  - Support for new device tree properties on PowerVM to describe hotpluggable
    memory and devices.
 
  - Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 64-bit VDSO.
 
  - Freescale updates from Scott:
      "Contains fixes for CPM GPIO and an FSL PCI erratum workaround, plus a
       minor cleanup patch."
 
 As well as quite a lot of other changes all over the place, and small fixes and
 cleanups as always.
 
 Thanks to:
   Alan Modra, Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple, Andreas
   Schwab, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman
   Khandual, Anton Blanchard, Arnd Bergmann, Balbir Singh, Benjamin
   Herrenschmidt, Bhaktipriya Shridhar, Bryant G. Ly, Cédric Le Goater,
   Christophe Leroy, Christophe Lombard, Cyril Bur, David Gibson, Desnes A. Nunes
   do Rosario, Dmitry Torokhov, Frederic Barrat, Geert Uytterhoeven, Guilherme G.
   Piccoli, Gustavo A. R. Silva, Gustavo Romero, Ivan Mikhaylov, Joakim
   Tjernlund, Joe Perches, Josh Poimboeuf, Juan J. Alvarez, Julia Cartwright,
   Kamalesh Babulal, Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre,
   Michael Bringmann, Michael Hanselmann, Michael Neuling, Nathan Fontenot,
   Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Philippe Bergheaud, Ram Pai,
   Russell Currey, Santosh Sivaraj, Scott Wood, Seth Forshee, Simon Guo, Stewart
   Smith, Sukadev Bhattiprolu, Thiago Jung Bauermann, Vaibhav Jain, Vasyl
   Gomonovych.
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Merge tag 'powerpc-4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Highlights:

   - Enable support for memory protection keys aka "pkeys" on Power7/8/9
     when using the hash table MMU.

   - Extend our interrupt soft masking to support masking PMU interrupts
     as well as "normal" interrupts, and then use that to implement
     local_t for a ~4x speedup vs the current atomics-based
     implementation.

   - A new driver "ocxl" for "Open Coherent Accelerator Processor
     Interface (OpenCAPI)" devices.

   - Support for new device tree properties on PowerVM to describe
     hotpluggable memory and devices.

   - Add support for CLOCK_{REALTIME/MONOTONIC}_COARSE to the 64-bit
     VDSO.

   - Freescale updates from Scott: fixes for CPM GPIO and an FSL PCI
     erratum workaround, plus a minor cleanup patch.

  As well as quite a lot of other changes all over the place, and small
  fixes and cleanups as always.

  Thanks to: Alan Modra, Alastair D'Silva, Alexey Kardashevskiy,
  Alistair Popple, Andreas Schwab, Andrew Donnellan, Aneesh Kumar K.V,
  Anju T Sudhakar, Anshuman Khandual, Anton Blanchard, Arnd Bergmann,
  Balbir Singh, Benjamin Herrenschmidt, Bhaktipriya Shridhar, Bryant G.
  Ly, Cédric Le Goater, Christophe Leroy, Christophe Lombard, Cyril Bur,
  David Gibson, Desnes A. Nunes do Rosario, Dmitry Torokhov, Frederic
  Barrat, Geert Uytterhoeven, Guilherme G. Piccoli, Gustavo A. R. Silva,
  Gustavo Romero, Ivan Mikhaylov, Joakim Tjernlund, Joe Perches, Josh
  Poimboeuf, Juan J. Alvarez, Julia Cartwright, Kamalesh Babulal,
  Madhavan Srinivasan, Mahesh Salgaonkar, Mathieu Malaterre, Michael
  Bringmann, Michael Hanselmann, Michael Neuling, Nathan Fontenot,
  Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Philippe Bergheaud,
  Ram Pai, Russell Currey, Santosh Sivaraj, Scott Wood, Seth Forshee,
  Simon Guo, Stewart Smith, Sukadev Bhattiprolu, Thiago Jung Bauermann,
  Vaibhav Jain, Vasyl Gomonovych"

* tag 'powerpc-4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (199 commits)
  powerpc/mm/radix: Fix build error when RADIX_MMU=n
  macintosh/ams-input: Use true and false for boolean values
  macintosh: change some data types from int to bool
  powerpc/watchdog: Print the NIP in soft_nmi_interrupt()
  powerpc/watchdog: regs can't be null in soft_nmi_interrupt()
  powerpc/watchdog: Tweak watchdog printks
  powerpc/cell: Remove axonram driver
  rtc-opal: Fix handling of firmware error codes, prevent busy loops
  powerpc/mpc52xx_gpt: make use of raw_spinlock variants
  macintosh/adb: Properly mark continued kernel messages
  powerpc/pseries: Fix cpu hotplug crash with memoryless nodes
  powerpc/numa: Ensure nodes initialized for hotplug
  powerpc/numa: Use ibm,max-associativity-domains to discover possible nodes
  powerpc/kernel: Block interrupts when updating TIDR
  powerpc/powernv/idoa: Remove unnecessary pcidev from pci_dn
  powerpc/mm/nohash: do not flush the entire mm when range is a single page
  powerpc/pseries: Add Initialization of VF Bars
  powerpc/pseries/pci: Associate PEs to VFs in configure SR-IOV
  powerpc/eeh: Add EEH notify resume sysfs
  powerpc/eeh: Add EEH operations to notify resume
  ...
2018-02-02 10:01:04 -08:00
Sukadev Bhattiprolu 384dfd627f powerpc/kernel: Block interrupts when updating TIDR
clear_thread_tidr() is called in interrupt context as a part of delayed
put of the task structure (i.e as a part of timer interrupt). To prevent
a deadlock, block interrupts when holding vas_thread_id_lock to set/
clear TIDR for a task.

Fixes: ec233ede4c ("powerpc: Add support for setting SPRN_TIDR")
Cc: stable@vger.kernel.org # v4.15+
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-27 20:54:57 +11:00
Eric W. Biederman f71dd7dc2d signal/ptrace: Add force_sig_ptrace_errno_trap and use it where needed
There are so many places that build struct siginfo by hand that at
least one of them is bound to get it wrong.  A handful of cases in the
kernel arguably did just that when using the errno field of siginfo to
pass no errno values to userspace.  The usage is limited to a single
si_code so at least does not mess up anything else.

Encapsulate this questionable pattern in a helper function so
that the userspace ABI is preserved.

Update all of the places that use this pattern to use the new helper
function.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-22 19:07:11 -06:00
Eric W. Biederman 47355040d2 signal/powerpc: Remove unnecessary signal_code parameter of do_send_trap
signal_code is always TRAP_HWBKPT

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2018-01-22 19:07:10 -06:00
Michael Ellerman ebf0b6a8b1 Merge branch 'fixes' into next
Merge our fixes branch from the 4.15 cycle.

Unusually the fixes branch saw some significant features merged,
notably the RFI flush patches, so we want the code in next to be
tested against that, to avoid any surprises when the two are merged.

There's also some other work on the panic handling that was reverted
in fixes and we now want to do properly in next, which would conflict.

And we also fix a few other minor merge conflicts.
2018-01-21 23:21:14 +11:00
Ram Pai 06bb53b338 powerpc: store and restore the pkey state across context switches
Store and restore the AMR, IAMR and UAMOR register state of the task
before scheduling out and after scheduling in, respectively.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-20 22:59:00 +11:00
Christophe Lombard b1db551324 cxl: Add support for ASB_Notify on POWER9
The POWER9 core supports a new feature: ASB_Notify which requires the
support of the Special Purpose Register: TIDR.

The ASB_Notify command, generated by the AFU, will attempt to
wake-up the host thread identified by the particular LPID:PID:TID.

This patch assign a unique TIDR (thread id) for the current thread which
will be used in the process element entry.

Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Philippe Bergheaud <felix@linux.vnet.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Reviewed-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 23:19:37 +11:00
Madhavan Srinivasan c2e480ba82 powerpc/64: Add #defines for paca->soft_enabled flags
Two #defines IRQS_ENABLED and IRQS_DISABLED are added to be used when
updating paca->soft_enabled. Replace the hardcoded values used when
updating paca->soft_enabled with IRQ_(EN|DIS)ABLED #define. No logic
change.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-19 22:36:56 +11:00
Benjamin Herrenschmidt 2271db20e4 powerpc: Use the TRAP macro whenever comparing a trap number
Trap numbers can have extra bits at the bottom that need to
be filtered out. There are a few cases where we don't do that.

It's possible that we got lucky but better safe than sorry.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-01-16 23:51:43 +11:00
Michael Ellerman 182dc9c7f2 powerpc/kernel: Print actual address of regs when oopsing
When we oops or otherwise call show_regs() we print the address of the
regs structure. Being able to see the address is fairly useful,
firstly to verify that the regs pointer is not completely bogus, and
secondly it allows you to dump the regs and surrounding memory with a
debugger if you have one.

In the normal case the regs will be located somewhere on the stack, so
printing their location discloses no further information than printing
the stack pointer does already.

So switch to %px and print the actual address, not the hashed value.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-19 13:09:40 +11:00
Vaibhav Jain 7e4d423326 powerpc: Do not assign thread.tidr if already assigned
If set_thread_tidr() is called twice for same task_struct then it will
allocate a new tidr value to it leaving the previous value still
dangling in the vas_thread_ida table.

To fix this the patch changes set_thread_tidr() to check if a tidr
value is already assigned to the task_struct and if yes then returns
zero.

Fixes: ec233ede4c86("powerpc: Add support for setting SPRN_TIDR")
Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
[mpe: Modify to return 0 in the success case, not the TID value]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-29 19:56:18 +11:00
Vaibhav Jain aca7573fde powerpc: Avoid signed to unsigned conversion in set_thread_tidr()
There is an unsafe signed to unsigned conversion in set_thread_tidr()
that may cause an error value to be assigned to SPRN_TIDR register and
used as thread-id.

The issue happens as assign_thread_tidr() returns an int and
thread.tidr is an unsigned-long. So a negative error code returned
from assign_thread_tidr() will fail the error check and gets assigned
as tidr as a large positive value.

To fix this the patch assigns the return value of assign_thread_tidr()
to a temporary int and assigns it to thread.tidr iff its '> 0'.

The patch shouldn't impact the calling convention of set_thread_tidr()
i.e all -ve return-values are error codes and a return value of '0'
indicates success.

Fixes: ec233ede4c86("powerpc: Add support for setting SPRN_TIDR")
Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Reviewed-by: Christophe Lombard clombard@linux.vnet.ibm.com
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-29 19:36:13 +11:00
Sukadev Bhattiprolu 9d2a4d7133 powerpc: Define set_thread_uses_vas()
A CP_ABORT instruction is required in processes that have mapped a VAS
"paste address" with the intention of using COPY/PASTE instructions.
But since CP_ABORT is expensive, we want to restrict it to only
processes that use/intend to use COPY/PASTE.

Define an interface, set_thread_uses_vas(), that VAS can use to
indicate that the current process opened a send window. During context
switch, issue CP_ABORT only for processes that have the flag set.

Thanks for input from Nick Piggin, Michael Ellerman.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
[mpe: Fix to not use new_thread after _switch() returns]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12 09:03:09 +11:00
Sukadev Bhattiprolu ec233ede4c powerpc: Add support for setting SPRN_TIDR
We need the SPRN_TIDR to be set for use with fast thread-wakeup (core-
to-core wakeup) and also with CAPI.

Each thread in a process needs to have a unique id within the process.
But for now, we assign globally unique thread ids to all threads in
the system.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Philippe Bergheaud <felix@linux.vnet.ibm.com>
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
[mpe: Simplify tidr clearing on fork() and ctx switch code]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-12 09:03:09 +11:00
Cyril Bur eb5c3f1c86 powerpc: Always save/restore checkpointed regs during treclaim/trecheckpoint
Lazy save and restore of FP/Altivec means that a userspace process can
be sent to userspace with FP or Altivec disabled and loaded only as
required (by way of an FP/Altivec unavailable exception). Transactional
Memory complicates this situation as a transaction could be started
without FP/Altivec being loaded up. This causes the hardware to
checkpoint incorrect registers. Handling FP/Altivec unavailable
exceptions while a thread is transactional requires a reclaim and
recheckpoint to ensure the CPU has correct state for both sets of
registers.

tm_reclaim() has optimisations to not always save the FP/Altivec
registers to the checkpointed save area. This was originally done
because the caller might have information that the checkpointed
registers aren't valid due to lazy save and restore. We've also been a
little vague as to how tm_reclaim() leaves the FP/Altivec state since it
doesn't necessarily always save it to the thread struct. This has lead
to an (incorrect) assumption that it leaves the checkpointed state on
the CPU.

tm_recheckpoint() has similar optimisations in reverse. It may not
always reload the checkpointed FP/Altivec registers from the thread
struct before the trecheckpoint. It is therefore quite unclear where it
expects to get the state from. This didn't help with the assumption
made about tm_reclaim().

These optimisations sit in what is by definition a slow path. If a
process has to go through a reclaim/recheckpoint then its transaction
will be doomed on returning to userspace. This mean that the process
will be unable to complete its transaction and be forced to its failure
handler. This is already an out if line case for userspace. Furthermore,
the cost of copying 64 times 128 bits from registers isn't very long[0]
(at all) on modern processors. As such it appears these optimisations
have only served to increase code complexity and are unlikely to have
had a measurable performance impact.

Our transactional memory handling has been riddled with bugs. A cause
of this has been difficulty in following the code flow, code complexity
has not been our friend here. It makes sense to remove these
optimisations in favour of a (hopefully) more stable implementation.

This patch does mean that some times the assembly will needlessly save
'junk' registers which will subsequently get overwritten with the
correct value by the C code which calls the assembly function. This
small inefficiency is far outweighed by the reduction in complexity for
general TM code, context switching paths, and transactional facility
unavailable exception handler.

0: I tried to measure it once for other work and found that it was
hiding in the noise of everything else I was working with. I find it
exceedingly likely this will be the case here.

Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06 20:39:33 +11:00
Cyril Bur 91381b9cb1 powerpc: Force reload for recheckpoint during tm {fp, vec, vsx} unavailable exception
Lazy save and restore of FP/Altivec means that a userspace process can
be sent to userspace with FP or Altivec disabled and loaded only as
required (by way of an FP/Altivec unavailable exception). Transactional
Memory complicates this situation as a transaction could be started
without FP/Altivec being loaded up. This causes the hardware to
checkpoint incorrect registers. Handling FP/Altivec unavailable
exceptions while a thread is transactional requires a reclaim and
recheckpoint to ensure the CPU has correct state for both sets of
registers.

tm_reclaim() has optimisations to not always save the FP/Altivec
registers to the checkpointed save area. This was originally done
because the caller might have information that the checkpointed
registers aren't valid due to lazy save and restore. We've also been a
little vague as to how tm_reclaim() leaves the FP/Altivec state since it
doesn't necessarily always save it to the thread struct. This has lead
to an (incorrect) assumption that it leaves the checkpointed state on
the CPU.

tm_recheckpoint() has similar optimisations in reverse. It may not
always reload the checkpointed FP/Altivec registers from the thread
struct before the trecheckpoint. It is therefore quite unclear where it
expects to get the state from. This didn't help with the assumption
made about tm_reclaim().

This patch is a minimal fix for ease of backporting. A more correct fix
which removes the msr parameter to tm_reclaim() and tm_recheckpoint()
altogether has been upstreamed to apply on top of this patch.

Fixes: dc3106690b ("powerpc: tm: Always use fp_state and vr_state to
store live registers")

Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06 20:39:33 +11:00
Cyril Bur a7771176b4 powerpc: Don't enable FP/Altivec if not checkpointed
Lazy save and restore of FP/Altivec means that a userspace process can
be sent to userspace with FP or Altivec disabled and loaded only as
required (by way of an FP/Altivec unavailable exception). Transactional
Memory complicates this situation as a transaction could be started
without FP/Altivec being loaded up. This causes the hardware to
checkpoint incorrect registers. Handling FP/Altivec unavailable
exceptions while a thread is transactional requires a reclaim and
recheckpoint to ensure the CPU has correct state for both sets of
registers.

Lazy save and restore of FP/Altivec cannot be done if a process is
transactional. If a facility was enabled it must remain enabled whenever
a thread is transactional.

Commit dc16b553c9 ("powerpc: Always restore FPU/VEC/VSX if hardware
transactional memory in use") ensures that the facilities are always
enabled if a thread is transactional. A bug in the introduced code may
cause it to inadvertently enable a facility that was (and should remain)
disabled. The problem with this extraneous enablement is that the
registers for the erroneously enabled facility have not been correctly
recheckpointed - the recheckpointing code assumed the facility would
remain disabled.

Further compounding the issue, the transactional {fp,altivec,vsx}
unavailable code has been incorrectly using the MSR to enable
facilities. The presence of the {FP,VEC,VSX} bit in the regs->msr simply
means if the registers are live on the CPU, not if the kernel should
load them before returning to userspace. This has worked due to the bug
mentioned above.

This causes transactional threads which return to their failure handler
to observe incorrect checkpointed registers. Perhaps an example will
help illustrate the problem:

A userspace process is running and uses both FP and Altivec registers.
This process then continues to run for some time without touching
either sets of registers. The kernel subsequently disables the
facilities as part of lazy save and restore. The userspace process then
performs a tbegin and the CPU checkpoints 'junk' FP and Altivec
registers. The process then performs a floating point instruction
triggering a fp unavailable exception in the kernel.

The kernel then loads the FP registers - and only the FP registers.
Since the thread is transactional it must perform a reclaim and
recheckpoint to ensure both the checkpointed registers and the
transactional registers are correct. It then (correctly) enables
MSR[FP] for the process. Later (on exception exist) the kernel also
(inadvertently) enables MSR[VEC]. The process is then returned to
userspace.

Since the act of loading the FP registers doomed the transaction we know
CPU will fail the transaction, restore its checkpointed registers, and
return the process to its failure handler. The problem is that we're
now running with Altivec enabled and the 'junk' checkpointed registers
are restored. The kernel had only recheckpointed FP.

This patch solves this by only activating FP/Altivec if userspace was
using them when it entered the kernel and not simply if the process is
transactional.

Fixes: dc16b553c9 ("powerpc: Always restore FPU/VEC/VSX if hardware
transactional memory in use")

Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06 20:39:32 +11:00
Michael Ellerman 4e00374704 powerpc/64s: Replace CONFIG_PPC_STD_MMU_64 with CONFIG_PPC_BOOK3S_64
CONFIG_PPC_STD_MMU_64 indicates support for the "standard" powerpc MMU
on 64-bit CPUs. The "standard" MMU refers to the hash page table MMU
found in "server" processors, from IBM mainly.

Currently CONFIG_PPC_STD_MMU_64 is == CONFIG_PPC_BOOK3S_64. While it's
annoying to have two symbols that always have the same value, it's not
quite annoying enough to bother removing one.

However with the arrival of Power9, we now have the situation where
CONFIG_PPC_STD_MMU_64 is enabled, but the kernel is running using the
Radix MMU - *not* the "standard" MMU. So it is now actively confusing
to use it, because it implies that code is disabled or inactive when
the Radix MMU is in use, however that is not necessarily true.

So s/CONFIG_PPC_STD_MMU_64/CONFIG_PPC_BOOK3S_64/, and do some minor
formatting updates of some of the affected lines.

This will be a pain for backports, but c'est la vie.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06 16:48:14 +11:00
Michael Neuling 92fb8690bd powerpc/tm: P9 disable transactionally suspended sigcontexts
Unfortunately userspace can construct a sigcontext which enables
suspend. Thus userspace can force Linux into a path where trechkpt is
executed.

This patch blocks this from happening on POWER9 by sanity checking
sigcontexts passed in.

ptrace doesn't have this problem as only MSR SE and BE can be changed
via ptrace.

This patch also adds a number of WARN_ON()s in case we ever enter
suspend when we shouldn't. This should not happen, but if it does the
symptoms are soft lockup warnings which are not obviously TM related,
so the WARN_ON()s should make it obvious what's happening.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-21 09:36:28 +11:00
Michael Ellerman 54820530c5 powerpc/powernv: Enable TM without suspend if possible
Some Power9 revisions can run in a mode where TM operates without
suspended state. If we find ourself on a CPU that might be in this
mode, we query OPAL to check, and if so we reenable TM in CPU
features, and enable a new user feature to signal to userspace that we
are in this mode.

We do not enable the "normal" user feature, PPC_FEATURE2_HTM, but we
do enable PPC_FEATURE2_HTM_NOSC because that indicates to userspace
that the kernel will abort transactions on syscall entry, which is
true regardless of the suspend mode.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-21 09:33:05 +11:00
Kautuk Consul 4ca360f3db powerpc: get_wchan(): solve possible race scenario due to parallel wakeup
Add a check for p->state == TASK_RUNNING so that any wake-ups on
task_struct p in the interim lead to 0 being returned by get_wchan().

Signed-off-by: Kautuk Consul <kautuk.consul.1980@gmail.com>
[mpe: Confirmed other architectures do similar]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-10-06 20:51:52 +11:00
Michael Ellerman a6036100ed powerpc/oops: Line up NIP & MSR with other rows
This is purely cosmetic, but does look nicer IMHO:

Before:

  task: c000000001453400 task.stack: c000000001c6c000
  NIP: c000000000a0fbfc LR: c000000000a0fbf4 CTR: c000000000ba6220
  REGS: c0000001fffef820 TRAP: 0300   Not tainted  (4.13.0-rc6-gcc-6.3.1-00234-g423af27f7d81)
  MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE>  CR: 88088242  XER: 00000000
  CFAR: c0000000000b3488 DAR: 0000000000000000 DSISR: 42000000 SOFTE: 0

After:
  task: c000000001453400 task.stack: c000000001c6c000
  NIP:  c000000000a0fbfc LR: c000000000a0fbf4 CTR: c000000000ba6220
  REGS: c0000001fffef820 TRAP: 0300   Not tainted  (4.13.0-rc6-gcc-6.3.1-00234-g423af27f7d81-dirty)
  MSR:  8000000000009033 <SF,EE,ME,IR,DR,RI,LE>  CR: 88088242  XER: 00000000
  CFAR: c0000000000b34a4 DAR: 0000000000000000 DSISR: 42000000 SOFTE: 0

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-28 22:10:00 +10:00
Michael Ellerman f6fc73fb96 powerpc/oops: Print CR/XER on same line as MSR
Somehow we missed this when the pr_cont() changes went in. Fix CR/XER
to go on the same line as MSR, as they have historically, eg:

  MSR: 8000000000009032 <SF,EE,ME,IR,DR,RI>  CR: 4804408a  XER: 20000000

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-28 22:09:59 +10:00
Nicholas Piggin d1d0d5ffb3 powerpc/64: Optimise set/clear of CTRL[RUN] (runlatch)
On modern CPUs the CTRL register is read-only except bit 63 which is
the run latch control. This means it can be updated with a mtspr
rather than mfspr/mtspr.

To accomodate older CPUs (Cell at least), where there are other bits
in the register, we still do a read/modify/write on pre 2.06 CPUs.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Update change log to mention 2.06 workaround]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-23 23:48:38 +10:00
Michael Ellerman 15c659ff9d Merge branch 'fixes' into next
There's a non-trivial dependency between some commits we want to put in
next and the KVM prefetch work around that went into fixes. So merge
fixes into next.
2017-08-23 22:20:10 +10:00
Benjamin Herrenschmidt 96c79b6bd7 powerpc: Remove more redundant VSX save/tests
__giveup_vsx/save_vsx are completely equivalent to testing MSR_FP
and MSR_VEC and calling the corresponding giveup/save function so
just remove the spurious VSX cases. Also add WARN_ONs checking that
we never have VSX enabled without the two other.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16 22:35:04 +10:00
Benjamin Herrenschmidt dc801081f2 powerpc: Remove redundant clear of MSR_VSX in __giveup_vsx()
__giveup_fpu() already does it and we cannot have MSR_VSX set
without having MSR_FP also set.

This also adds a warning to check we indeed do

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16 22:35:03 +10:00
Benjamin Herrenschmidt 746874d31c powerpc: Remove redundant FP/Altivec giveup code
__giveup_vsx() already calls those two functions.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16 22:34:42 +10:00
Benjamin Herrenschmidt 6a303833b5 powerpc: Fix missing newline before {
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16 22:34:34 +10:00
Benjamin Herrenschmidt 5a69aec945 powerpc: Fix VSX enabling/flushing to also test MSR_FP and MSR_VEC
VSX uses a combination of the old vector registers, the old FP
registers and new "second halves" of the FP registers.

Thus when we need to see the VSX state in the thread struct
(flush_vsx_to_thread()) or when we'll use the VSX in the kernel
(enable_kernel_vsx()) we need to ensure they are all flushed into
the thread struct if either of them is individually enabled.

Unfortunately we only tested if the whole VSX was enabled, not if they
were individually enabled.

Fixes: 72cd7b44bc ("powerpc: Uncomment and make enable_kernel_vsx() routine available")
Cc: stable@vger.kernel.org # v4.3+
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-16 19:35:54 +10:00
Michael Ellerman 44a12806d0 Revert "powerpc/64: Avoid restore_math call if possible in syscall exit"
This reverts commit bc4f65e4cf.

As reported by Andreas, this commit is causing unrecoverable SLB misses in the
system call exit path:

  Unrecoverable exception 4100 at c00000000000a1ec
  Oops: Unrecoverable exception, sig: 6 [#1]
  SMP NR_CPUS=2 PowerMac
  ...
  CPU: 0 PID: 18626 Comm: rm Not tainted 4.13.0-rc3 #1
  task: c00000018335e080 task.stack: c000000139e50000
  NIP: c00000000000a1ec LR: c00000000000a118 CTR: 0000000000000000
  REGS: c000000139e53bb0 TRAP: 4100   Not tainted  (4.13.0-rc3)
  MSR: 9000000000001030 <SF,HV,ME,IR,DR> CR: 24000044  XER: 20000000 SOFTE: 1
  GPR00: 0000000000000000 c000000139e53e30 c000000000abb500 fffffffffffffffe
  GPR04: c0000001eb866298 0000000000000000 0000000000000000 c00000018335e080
  GPR08: 900000000000d032 0000000000000000 0000000000000002 fffffffffffff001
  GPR12: c000000139e50000 c00000000ffff000 00003fffa8c0dca0 00003fffa8c0dc88
  GPR16: 0000000010000000 0000000000000001 00003fffa8c0eaa0 0000000000000000
  GPR20: 00003fffa8c27528 00003fffa8c27b00 0000000000000000 0000000000000000
  GPR24: 00003fffa8c0d918 00003ffff1b3efa0 00003fffa8c26d68 0000000000000000
  GPR28: 00003fffa8c249e8 00003fffa8c263d0 00003fffa8c27550 00003ffff1b3ef10
  NIP [c00000000000a1ec] system_call_exit+0xc0/0x21c
  LR [c00000000000a118] system_call+0x58/0x6c
  Call Trace:
  [c000000139e53e30] [c00000000000a118] system_call+0x58/0x6c (unreliable)
  Instruction dump:
  64a51000 7c6300d0 f8a101a0 4bffff9c 3c000000 60000006 780007c6 64000000
  60000000 7c004039 4082001c e8ed0170 <88070b78> 88c70b79 7c003214 2c200000

This is caused by us trying to load THREAD_LOAD_FP with MSR_RI=0, and taking an
SLB miss on the thread struct.

Reported-by: Andreas Schwab <schwab@linux-m68k.org>
Diagnosed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-07 21:36:56 +10:00
Michael Ellerman 218ea31039 Merge branch 'fixes' into next
Merge our fixes branch, a few of them are tripping people up while
working on top of next, and we also have a dependency between the CXL
fixes and new CXL code we want to merge into next.
2017-07-03 23:05:43 +10:00
Nicholas Piggin 07d2a628bc powerpc/64s: Avoid cpabort in context switch when possible
The ISA v3.0B copy-paste facility only requires cpabort when switching
to a process that has foreign real addresses mapped (direct access to
accelerators), to clear a potential copy buffer filled by a previous
thread. There is no accelerator driver implemented yet, so cpabort can
be removed. It can be be re-added when a driver is implemented.

POWER9 DD1 requires the copy buffer to always be cleared on context
switch, but if accelerators are not in use, then an unpaired copy from
a dummy region is sufficient to clear data out of the copy buffer.

This increases context switch performance by about 5% on POWER9.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-15 16:34:39 +10:00
Nicholas Piggin e4c0fc5f72 powerpc/64s: Leave interrupts hard enabled in context switch for radix
Commit 4387e9ff25 ("[POWERPC] Fix PMU + soft interrupt disable bug")
hard disabled interrupts over the low level context switch, because
the SLB management can't cope with a PMU interrupt accesing the stack
in that window.

Radix based kernel mapping does not use the SLB so it does not require
interrupts hard disabled here.

This is worth 1-2% in context switch performance on POWER9.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-15 16:34:39 +10:00
Nicholas Piggin bc4f65e4cf powerpc/64: Avoid restore_math call if possible in syscall exit
The syscall exit code that branches to restore_math is quite heavy on
Book3S, consisting of 2 mtmsr instructions. Threads that don't use both
FP and vector can get caught here if the kernel ever uses FP or vector.
Lazy-FP/vec context switching also trips this case.

So check for lazy FP and vector before switching RI for restore_math.
Move most of this case out of line.

For threads that do want to restore math registers, the MSR switches are
still suboptimal. Future direction may be to use a soft-RI bit to avoid
MSR switches in kernel (similar to soft-EE), but for now at least the
no-restore

POWER9 context switch rate increases by about 5% due to sched_yield(2)
return performance. I haven't constructed a test to measure the syscall
cost.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-15 16:34:39 +10:00
Breno Leitao 7f22ced437 powerpc/kernel: Initialize load_tm on task creation
Currently tsk->thread.load_tm is not initialized in the task creation
and can contain garbage on a new task.

This is an undesired behaviour, since it affects the timing to enable
and disable the transactional memory laziness (disabling and enabling
the MSR TM bit, which affects TM reclaim and recheckpoint in the
scheduling process).

Fixes: 5d176f751e ("powerpc: tm: Enable transactional memory (TM) lazily for userspace")
Cc: stable@vger.kernel.org # v4.9+
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-06 19:09:22 +10:00
Breno Leitao 1195892c09 powerpc/kernel: Fix FP and vector register restoration
Currently tsk->thread->load_vec and load_fp are not initialized during
task creation, which can lead to garbage values in these variables (non-zero
values).

These variables will be checked later in restore_math() to validate if the
FP and vector registers are being utilized. Since these values might be
non-zero, the restore_math() will continue to save the FP and vectors even if
they were never utilized by the userspace application. load_fp and load_vec
counters will then overflow (they wrap at 255) and the FP and Altivec will be
finally disabled, but before that condition is reached (counter overflow)
several context switches will have restored FP and vector registers without
need, causing a performance degradation.

Fixes: 70fe3d980f ("powerpc: Restore FPU/VEC/VSX if previously used")
Cc: stable@vger.kernel.org # v4.6+
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Gustavo Romero <gusbromero@gmail.com>
Acked-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-05 15:55:30 +10:00
Michael Neuling f48e91e87e powerpc/tm: Fix FP and VMX register corruption
In commit dc3106690b ("powerpc: tm: Always use fp_state and vr_state
to store live registers"), a section of code was removed that copied
the current state to checkpointed state. That code should not have been
removed.

When an FP (Floating Point) unavailable is taken inside a transaction,
we need to abort the transaction. This is because at the time of the
tbegin, the FP state is bogus so the state stored in the checkpointed
registers is incorrect. To fix this, we treclaim (to get the
checkpointed GPRs) and then copy the thread_struct FP live state into
the checkpointed state. We then trecheckpoint so that the FP state is
correctly restored into the CPU.

The copying of the FP registers from live to checkpointed is what was
missing.

This simplifies the logic slightly from the original patch.
tm_reclaim_thread() will now always write the checkpointed FP
state. Either the checkpointed FP state will be written as part of
the actual treclaim (in tm.S), or it'll be a copy of the live
state. Which one we use is based on MSR[FP] from userspace.

Similarly for VMX.

Fixes: dc3106690b ("powerpc: tm: Always use fp_state and vr_state to store live registers")
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: cyrilbur@gmail.com
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-05-15 19:31:38 +10:00
Ingo Molnar 68db0cf106 sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task_stack.h>
We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/task_stack.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:36 +01:00
Ingo Molnar 299300258d sched/headers: Prepare for new header dependencies before moving code to <linux/sched/task.h>
We are going to split <linux/sched/task.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/task.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:35 +01:00
Ingo Molnar b17b01533b sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>
We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder <linux/sched/debug.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:34 +01:00
Linus Torvalds b286cedd47 powerpc updates for 4.11 part 2
Highlights include:
 
  - An update of the disassembly code used by xmon to the latest versions in
    binutils. We've received permission from all the authors of the relevant
    binutils changes to relicense their changes to the relevant files from GPLv3
    to GPLv2, for inclusion in Linux. Thanks to Peter Bergner for doing the leg
    work to get permission from everyone.
 
  - Addition of the "architected" Power9 CPU table entry, allowing us to boot
    in Power9 architected mode under a hypervisor.
 
  - Updates to the Power9 PMU code.
 
  - Implementation of clear_bit_unlock_is_negative_byte() to optimise
    unlock_page().
 
  - Freescale updates from Scott: "Highlights include 8xx breakpoints and perf,
    t1042rdb display support, and board updates."
 
 Thanks to:
   Al Viro, Andrew Donnellan, Aneesh Kumar K.V, Balbir Singh, Douglas Miller,
   Frédéric Weisbecker, Gavin Shan, Madhavan Srinivasan, Michael Roth, Nathan
   Fontenot, Naveen N. Rao, Nicholas Piggin, Peter Bergner, Paul E. McKenney,
   Rashmica Gupta, Russell Currey, Sahil Mehta, Stewart Smith.
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Merge tag 'powerpc-4.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull more powerpc updates from Michael Ellerman:
 "Highlights include:

   - an update of the disassembly code used by xmon to the latest
     versions in binutils. We've received permission from all the
     authors of the relevant binutils changes to relicense their changes
     to the relevant files from GPLv3 to GPLv2, for inclusion in Linux.
     Thanks to Peter Bergner for doing the leg work to get permission
     from everyone.

   - addition of the "architected" Power9 CPU table entry, allowing us
     to boot in Power9 architected mode under a hypervisor.

   - updates to the Power9 PMU code.

   - implementation of clear_bit_unlock_is_negative_byte() to optimise
     unlock_page().

   - Freescale updates from Scott: "Highlights include 8xx breakpoints
     and perf, t1042rdb display support, and board updates."

  Thanks to:
    Al Viro, Andrew Donnellan, Aneesh Kumar K.V, Balbir Singh, Douglas
    Miller, Frédéric Weisbecker, Gavin Shan, Madhavan Srinivasan,
    Michael Roth, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Peter
    Bergner, Paul E. McKenney, Rashmica Gupta, Russell Currey, Sahil
    Mehta, Stewart Smith"

* tag 'powerpc-4.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (48 commits)
  powerpc: Remove leftover cputime_to_nsecs call causing build error
  powerpc/mm/hash: Always clear UPRT and Host Radix bits when setting up CPU
  powerpc/optprobes: Fix TOC handling in optprobes trampoline
  powerpc/pseries: Advertise Hot Plug Event support to firmware
  cxl: fix nested locking hang during EEH hotplug
  powerpc/xmon: Dump memory in CPU endian format
  powerpc/pseries: Revert 'Auto-online hotplugged memory'
  powerpc/powernv: Make PCI non-optional
  powerpc/64: Implement clear_bit_unlock_is_negative_byte()
  powerpc/powernv: Remove unused variable in pnv_pci_sriov_disable()
  powerpc/kernel: Remove error message in pcibios_setup_phb_resources()
  powerpc/mm: Fix typo in set_pte_at()
  pci/hotplug/pnv-php: Disable MSI and PCI device properly
  pci/hotplug/pnv-php: Disable surprise hotplug capability on conflicts
  pci/hotplug/pnv-php: Remove WARN_ON() in pnv_php_put_slot()
  powerpc: Add POWER9 architected mode to cputable
  powerpc/perf: use is_kernel_addr macro in perf_get_misc_flags()
  powerpc/perf: Avoid FAB_*_MATCH checks for power9
  powerpc/perf: Add restrictions to PMC5 in power9 DD1
  powerpc/perf: Use Instruction Counter value
  ...
2017-03-01 10:10:16 -08:00
Christophe Leroy 4ad8622dc5 powerpc/8xx: Implement hw_breakpoint
This patch implements HW breakpoint on the 8xx. The 8xx has
capability to manage HW breakpoints, which is slightly different
than BOOK3S:
1/ The breakpoint match doesn't trigger a DSI exception but a
dedicated data breakpoint exception.
2/ The breakpoint happens after the instruction has completed,
no need to single step or emulate the instruction,
3/ Matched address is not set in DAR but in BAR,
4/ DABR register doesn't exist, instead we have registers
LCTRL1, LCTRL2 and CMPx registers,
5/ The match on one comparator is not on a double word but
on a single word.

The patch does:
1/ Prepare the dedicated registers in call to __set_dabr(). In order
to emulate the double word handling of BOOK3S, comparator E is set to
DABR address value and comparator F to address + 4. Then breakpoint 1
is set to match comparator E or F,
2/ Skip the singlestepping stage when compiled for CONFIG_PPC_8xx,
3/ Implement the exception. In that exception, the matched address
is taken from SPRN_BAR and manage as if it was from SPRN_DAR.
4/ I/D TLB error exception routines perform a tlbie on bad TLBs. That
tlbie triggers the breakpoint exception when performed on the
breakpoint address. For this reason, the routine returns if the match
is from one of those two tlbie.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
2017-01-25 02:43:59 -06:00
Michael Ellerman f2574030b0 powerpc: Revert the initial stack protector support
Unfortunately the stack protector support we merged recently only works
on some toolchains. If the toolchain is built without glibc support
everything works fine, but if glibc is built then it leads to a panic
at boot.

The solution is not rc5 material, so revert the support for now. This
reverts commits:

6533b7c16e ("powerpc: Initial stack protector (-fstack-protector) support")
902e06eb86 ("powerpc/32: Change the stack protector canary value per task")

Fixes: 6533b7c16e ("powerpc: Initial stack protector (-fstack-protector) support")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-24 21:37:43 +11:00
Linus Torvalds de399813b5 powerpc updates for 4.10
Highlights include:
 
  - Support for the kexec_file_load() syscall, which is a prereq for secure and
    trusted boot.
 
  - Prevent kernel execution of userspace on P9 Radix (similar to SMEP/PXN).
 
  - Sort the exception tables at build time, to save time at boot, and store
    them as relative offsets to save space in the kernel image & memory.
 
  - Allow building the kernel with thin archives, which should allow us to build
    an allyesconfig once some other fixes land.
 
  - Build fixes to allow us to correctly rebuild when changing the kernel endian
    from big to little or vice versa.
 
  - Plumbing so that we can avoid doing a full mm TLB flush on P9 Radix.
 
  - Initial stack protector support (-fstack-protector).
 
  - Support for dumping the radix (aka. Linux) and hash page tables via debugfs.
 
  - Fix an oops in cxl coredump generation when cxl_get_fd() is used.
 
  - Freescale updates from Scott: "Highlights include 8xx hugepage support,
    qbman fixes/cleanup, device tree updates, and some misc cleanup."
 
  - Many and varied fixes and minor enhancements as always.
 
 Thanks to:
   Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual,
   Anton Blanchard, Balbir Singh, Bartlomiej Zolnierkiewicz, Christophe Jaillet,
   Christophe Leroy, Denis Kirjanov, Elimar Riesebieter, Frederic Barrat,
   Gautham R. Shenoy, Geliang Tang, Geoff Levand, Jack Miller, Johan Hovold,
   Lars-Peter Clausen, Libin, Madhavan Srinivasan, Michael Neuling, Nathan
   Fontenot, Naveen N. Rao, Nicholas Piggin, Pan Xinhui, Peter Senna Tschudin,
   Rashmica Gupta, Rui Teng, Russell Currey, Scott Wood, Simon Guo, Suraj
   Jitindar Singh, Thiago Jung Bauermann, Tobias Klauser, Vaibhav Jain.
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Merge tag 'powerpc-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Highlights include:

   - Support for the kexec_file_load() syscall, which is a prereq for
     secure and trusted boot.

   - Prevent kernel execution of userspace on P9 Radix (similar to
     SMEP/PXN).

   - Sort the exception tables at build time, to save time at boot, and
     store them as relative offsets to save space in the kernel image &
     memory.

   - Allow building the kernel with thin archives, which should allow us
     to build an allyesconfig once some other fixes land.

   - Build fixes to allow us to correctly rebuild when changing the
     kernel endian from big to little or vice versa.

   - Plumbing so that we can avoid doing a full mm TLB flush on P9
     Radix.

   - Initial stack protector support (-fstack-protector).

   - Support for dumping the radix (aka. Linux) and hash page tables via
     debugfs.

   - Fix an oops in cxl coredump generation when cxl_get_fd() is used.

   - Freescale updates from Scott: "Highlights include 8xx hugepage
     support, qbman fixes/cleanup, device tree updates, and some misc
     cleanup."

   - Many and varied fixes and minor enhancements as always.

  Thanks to:
    Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V, Anshuman
    Khandual, Anton Blanchard, Balbir Singh, Bartlomiej Zolnierkiewicz,
    Christophe Jaillet, Christophe Leroy, Denis Kirjanov, Elimar
    Riesebieter, Frederic Barrat, Gautham R. Shenoy, Geliang Tang, Geoff
    Levand, Jack Miller, Johan Hovold, Lars-Peter Clausen, Libin,
    Madhavan Srinivasan, Michael Neuling, Nathan Fontenot, Naveen N.
    Rao, Nicholas Piggin, Pan Xinhui, Peter Senna Tschudin, Rashmica
    Gupta, Rui Teng, Russell Currey, Scott Wood, Simon Guo, Suraj
    Jitindar Singh, Thiago Jung Bauermann, Tobias Klauser, Vaibhav Jain"

[ And thanks to Michael, who took time off from a new baby to get this
  pull request done.   - Linus ]

* tag 'powerpc-4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (174 commits)
  powerpc/fsl/dts: add FMan node for t1042d4rdb
  powerpc/fsl/dts: add sg_2500_aqr105_phy4 alias on t1024rdb
  powerpc/fsl/dts: add QMan and BMan nodes on t1024
  powerpc/fsl/dts: add QMan and BMan nodes on t1023
  soc/fsl/qman: test: use DEFINE_SPINLOCK()
  powerpc/fsl-lbc: use DEFINE_SPINLOCK()
  powerpc/8xx: Implement support of hugepages
  powerpc: get hugetlbpage handling more generic
  powerpc: port 64 bits pgtable_cache to 32 bits
  powerpc/boot: Request no dynamic linker for boot wrapper
  soc/fsl/bman: Use resource_size instead of computation
  soc/fsl/qe: use builtin_platform_driver
  powerpc/fsl_pmc: use builtin_platform_driver
  powerpc/83xx/suspend: use builtin_platform_driver
  powerpc/ftrace: Fix the comments for ftrace_modify_code
  powerpc/perf: macros for power9 format encoding
  powerpc/perf: power9 raw event format encoding
  powerpc/perf: update attribute_group data structure
  powerpc/perf: factor out the event format field
  powerpc/mm/iommu, vfio/spapr: Put pages on VFIO container shutdown
  ...
2016-12-16 09:26:42 -08:00
Christophe Leroy 6533b7c16e powerpc: Initial stack protector (-fstack-protector) support
Partialy copied from commit c743f38013 ("ARM: initial stack protector
(-fstack-protector) support")

This is the very basic stuff without the changing canary upon
task switch yet.  Just the Kconfig option and a constant canary
value initialized at boot time.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-23 22:57:15 +11:00
Michael Neuling 29a969b764 powerpc: Revert Load Monitor Register Support
Load monitored is no longer supported on POWER9 so let's remove the
code.

This reverts commit bd3ea317fd ("powerpc: Load Monitor Register
Support").

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-14 20:05:57 +11:00
Andrew Donnellan 2ffd04dee0 powerpc/oops: Fix missing pr_cont()s in instruction dump
Since the KERN_CONT changes, the current code in show_instructions()
prints out a whole bunch of unnecessary newlines. Change occurrences of
printk("\n") to pr_cont("\n"). While we're here, change all the other
cases of printk(KERN_CONT ...) to pr_cont() as well.

Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-12 20:12:51 +11:00
Michael Ellerman 7dae865f58 powerpc/oops: Fix missing pr_cont()s in show_regs()
Fix up our oops output by converting continuation lines to use
pr_cont(). Some of these are dubious, eg. printing a continuation line
which starts with a newline, but seem to work OK for now. This whole
function needs a rewrite in the next release.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-12 20:12:50 +11:00
Michael Ellerman db5ba5ae6e powerpc/oops: Fix missing pr_cont()s in print_msr_bits() et. al.
Since the KERN_CONT changes these are being horribly split across lines,
for example:

    MSR: 8000000000009033 <
    SF,EE
    ,ME,IR
    ,DR,RI
    ,LE>

So fix it by using pr_cont() where appropriate.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-11-12 20:12:50 +11:00