Non-highlights:
- Five fixes for the >128T address space handling, both to fix bugs in our
implementation and to bring the semantics exactly into line with x86.
Highlights:
- Support for a new OPAL call on bare metal machines which gives us a true NMI
(ie. is not masked by MSR[EE]=0) for debugging etc.
- Support for Power9 DD2 in the CXL driver.
- Improvements to machine check handling so that uncorrectable errors can be
reported into the generic memory_failure() machinery.
- Some fixes and improvements for VPHN, which is used under PowerVM to notify
the Linux partition of topology changes.
- Plumbing to enable TM (transactional memory) without suspend on some Power9
processors (PPC_FEATURE2_HTM_NO_SUSPEND).
- Support for emulating vector loads form cache-inhibited memory, on some
Power9 revisions.
- Disable the fast-endian switch "syscall" by default (behind a CONFIG), we
believe it has never had any users.
- A major rework of the API drivers use when initiating and waiting for long
running operations performed by OPAL firmware, and changes to the
powernv_flash driver to use the new API.
- Several fixes for the handling of FP/VMX/VSX while processes are using
transactional memory.
- Optimisations of TLB range flushes when using the radix MMU on Power9.
- Improvements to the VAS facility used to access coprocessors on Power9, and
related improvements to the way the NX crypto driver handles requests.
- Implementation of PMEM_API and UACCESS_FLUSHCACHE for 64-bit.
Thanks to:
Alexey Kardashevskiy, Alistair Popple, Allen Pais, Andrew Donnellan, Aneesh
Kumar K.V, Arnd Bergmann, Balbir Singh, Benjamin Herrenschmidt, Breno Leitao,
Christophe Leroy, Christophe Lombard, Cyril Bur, Frederic Barrat, Gautham R.
Shenoy, Geert Uytterhoeven, Guilherme G. Piccoli, Gustavo Romero, Haren
Myneni, Joel Stanley, Kamalesh Babulal, Kautuk Consul, Markus Elfring, Masami
Hiramatsu, Michael Bringmann, Michael Neuling, Michal Suchanek, Naveen N. Rao,
Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pedro Miraglia Franco de
Carvalho, Philippe Bergheaud, Sandipan Das, Seth Forshee, Shriya, Stephen
Rothwell, Stewart Smith, Sukadev Bhattiprolu, Tyrel Datwyler, Vaibhav Jain,
Vaidyanathan Srinivasan, William A. Kennington III.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=Rq81
-----END PGP SIGNATURE-----
Merge tag 'powerpc-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"A bit of a small release, I suspect in part due to me travelling for
KS. But my backlog of patches to review is smaller than usual, so I
think in part folks just didn't send as much this cycle.
Non-highlights:
- Five fixes for the >128T address space handling, both to fix bugs
in our implementation and to bring the semantics exactly into line
with x86.
Highlights:
- Support for a new OPAL call on bare metal machines which gives us a
true NMI (ie. is not masked by MSR[EE]=0) for debugging etc.
- Support for Power9 DD2 in the CXL driver.
- Improvements to machine check handling so that uncorrectable errors
can be reported into the generic memory_failure() machinery.
- Some fixes and improvements for VPHN, which is used under PowerVM
to notify the Linux partition of topology changes.
- Plumbing to enable TM (transactional memory) without suspend on
some Power9 processors (PPC_FEATURE2_HTM_NO_SUSPEND).
- Support for emulating vector loads form cache-inhibited memory, on
some Power9 revisions.
- Disable the fast-endian switch "syscall" by default (behind a
CONFIG), we believe it has never had any users.
- A major rework of the API drivers use when initiating and waiting
for long running operations performed by OPAL firmware, and changes
to the powernv_flash driver to use the new API.
- Several fixes for the handling of FP/VMX/VSX while processes are
using transactional memory.
- Optimisations of TLB range flushes when using the radix MMU on
Power9.
- Improvements to the VAS facility used to access coprocessors on
Power9, and related improvements to the way the NX crypto driver
handles requests.
- Implementation of PMEM_API and UACCESS_FLUSHCACHE for 64-bit.
Thanks to: Alexey Kardashevskiy, Alistair Popple, Allen Pais, Andrew
Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Balbir Singh, Benjamin
Herrenschmidt, Breno Leitao, Christophe Leroy, Christophe Lombard,
Cyril Bur, Frederic Barrat, Gautham R. Shenoy, Geert Uytterhoeven,
Guilherme G. Piccoli, Gustavo Romero, Haren Myneni, Joel Stanley,
Kamalesh Babulal, Kautuk Consul, Markus Elfring, Masami Hiramatsu,
Michael Bringmann, Michael Neuling, Michal Suchanek, Naveen N. Rao,
Nicholas Piggin, Oliver O'Halloran, Paul Mackerras, Pedro Miraglia
Franco de Carvalho, Philippe Bergheaud, Sandipan Das, Seth Forshee,
Shriya, Stephen Rothwell, Stewart Smith, Sukadev Bhattiprolu, Tyrel
Datwyler, Vaibhav Jain, Vaidyanathan Srinivasan, and William A.
Kennington III"
* tag 'powerpc-4.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (151 commits)
powerpc/64s: Fix Power9 DD2.0 workarounds by adding DD2.1 feature
powerpc/64s: Fix masking of SRR1 bits on instruction fault
powerpc/64s: mm_context.addr_limit is only used on hash
powerpc/64s/radix: Fix 128TB-512TB virtual address boundary case allocation
powerpc/64s/hash: Allow MAP_FIXED allocations to cross 128TB boundary
powerpc/64s/hash: Fix fork() with 512TB process address space
powerpc/64s/hash: Fix 128TB-512TB virtual address boundary case allocation
powerpc/64s/hash: Fix 512T hint detection to use >= 128T
powerpc: Fix DABR match on hash based systems
powerpc/signal: Properly handle return value from uprobe_deny_signal()
powerpc/fadump: use kstrtoint to handle sysfs store
powerpc/lib: Implement UACCESS_FLUSHCACHE API
powerpc/lib: Implement PMEM API
powerpc/powernv/npu: Don't explicitly flush nmmu tlb
powerpc/powernv/npu: Use flush_all_mm() instead of flush_tlb_mm()
powerpc/powernv/idle: Round up latency and residency values
powerpc/kprobes: refactor kprobe_lookup_name for safer string operations
powerpc/kprobes: Blacklist emulate_update_regs() from kprobes
powerpc/kprobes: Do not disable interrupts for optprobes and kprobes_on_ftrace
powerpc/kprobes: Disable preemption before invoking probe handler for optprobes
...
Add a self test to check if FP/VEC/VSX registers are sane (restored
correctly) after a FP/VEC/VSX unavailable exception is caught during a
transaction.
This test checks all possibilities in a thread regarding the combination
of MSR.[FP|VEC] states in a thread and for each scenario raises a
FP/VEC/VSX unavailable exception in transactional state, verifying if
vs0 and vs32 registers, which are representatives of FP/VEC/VSX reg
sets, are not corrupted.
Signed-off-by: Gustavo Romero <gromero@linux.vnet.ibm.com>
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't currently harmful.
However, for some features it is necessary to instrument reads and
writes separately, which is not possible with ACCESS_ONCE(). This
distinction is critical to correct operation.
The bulk of the kernel code can be transformed via Coccinelle to use
{READ,WRITE}_ONCE(), though this only modifies users of ACCESS_ONCE(),
and not the implementation itself. As such, it has the potential to
break homebrew ACCESS_ONCE() macros seen in some user code in the kernel
tree (e.g. the virtio code, as fixed in commit ea9156fb3b).
To avoid fragility if/when that transformation occurs, and to align with
the preferred usage of {READ,WRITE}_ONCE(), this patch updates the DSCR
selftest code to use READ_ONCE() rather than ACCESS_ONCE(). There should
be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-11-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Turns out pthreads returns an errno and doesn't set errno. This doesn't
play well with perror().
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently sprintf is used, and while paths should never exceed
the size of the buffer it is theoretically possible since
dirent.d_name is 256 bytes. As a result this trips
-Wformat-overflow, and since the test is built with -Wall -Werror
the causes the build to fail. Switch to using snprintf and skip
any paths which are too long for the filename buffer.
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently these tests won't build with a `--enable-default-pie`
compiler as they require r30 to be clobbered. This gives
an error:
ptrace-tm-spd-gpr.c:41:2: error: PIC register clobbered by 'r30' in 'asm'
This forces these tests to be built no-pie.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
.llong is an undocumented PPC specific directive. The generic
equivalent is .quad, but even better (because it's self describing) is
.8byte.
Convert all .llong directives to .8byte.
Signed-off-by: Tobin C. Harding <me@tobin.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The tm-resched-dscr self test can, in some situations, run for
several minutes before being successfully interrupted by the context
switch it needs in order to perform the test. This often seems to
occur when the test is being run in a virtual machine.
Improve the test by running it under eat_cpu() to guarantee
contention for the CPU and increase the chance of a context switch.
In practice this seems to reduce the test time, in some cases, from
more than two minutes to under a second.
Also remove the "progress dots" so that if the test does run for a
long time, it doesn't produce large amounts of unnecessary output.
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This reduces overhead of mutex locking and increases context switch
rate significantly (which helps to measure and profile the context
switch path).
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The tm-resched-dscr test has started failing sometimes, depending on
what compiler it's built with, eg:
test: tm_resched_dscr
Check DSCR TM context switch: tm-resched-dscr: tm-resched-dscr.c:76: test_body: Assertion `rv' failed.
!! child died by signal 6
When it fails we see that the compiler doesn't initialise rv to 1 before
entering the inline asm block. Although that's counter intuitive, it
is allowed because we tell the compiler that the inline asm will write
to rv (using "=r"), meaning the original value is irrelevant.
Marking it as a read/write parameter would presumably work, but it seems
simpler to fix it by setting the initial value of rv in the inline asm.
Fixes: 96d0161086 ("powerpc: Correct DSCR during TM context switch")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michael Neuling <mikey@neuling.org>
Test that the VMX checkpointed register state is maintained when a VMX
unavailable exception is taken during a transaction.
Thanks to Breno Leitao <brenohl@br.ibm.com> and
Gustavo Bueno Romero <gromero@br.ibm.com> for the original test this
is based heavily on.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Cyril Bur <cyrilbur@gmail.com>
[mpe: Add to .gitignore, always build it 64-bit to fix build errors]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This update consists of:
-- important fixes for build failures and clean target related warnings
to address regressions introduced in:
88baa78d1f ("selftests: remove duplicated all and clean target")
-- several minor spelling fixes in and log messages and comment blocks.
-- Enabling configs for better test coverage in ftrace, vm, cpufreq tests.
-- .gitignore changes
-----BEGIN PGP SIGNATURE-----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=9Fo1
-----END PGP SIGNATURE-----
Merge tag 'linux-kselftest-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kselftest updates from Shuah Khan:
"This update consists of:
- important fixes for build failures and clean target related
warnings to address regressions introduced in commit 88baa78d1f
("selftests: remove duplicated all and clean target")
- several minor spelling fixes in and log messages and comment
blocks.
- Enabling configs for better test coverage in ftrace, vm, and
cpufreq tests.
- .gitignore changes"
* tag 'linux-kselftest-4.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (26 commits)
selftests: x86: add missing executables to .gitignore
selftests: watchdog: accept multiple params on command line
selftests: create cpufreq kconfig fragments
selftests: x86: override clean in lib.mk to fix warnings
selftests: sync: override clean in lib.mk to fix warnings
selftests: splice: override clean in lib.mk to fix warnings
selftests: gpio: fix clean target to remove all generated files and dirs
selftests: add gpio generated files to .gitignore
selftests: powerpc: override clean in lib.mk to fix warnings
selftests: gpio: override clean in lib.mk to fix warnings
selftests: futex: override clean in lib.mk to fix warnings
selftests: lib.mk: define CLEAN macro to allow Makefiles to override clean
selftests: splice: fix clean target to not remove default_file_splice_read.sh
selftests: gpio: add config fragment for gpio-mockup
selftests: breakpoints: allow to cross-compile for aarch64/arm64
selftests/Makefile: Add missed PHONY targets
selftests/vm/run_vmtests: Fix wrong comment
selftests/Makefile: Add missed closing `"` in comment
selftests/vm/run_vmtests: Polish output text
selftests/timers: fix spelling mistake: "Asynchronous"
...
Highlights include:
- Larger virtual address space on 64-bit server CPUs. By default we use a 128TB
virtual address space, but a process can request access to the full 512TB by
passing a hint to mmap().
- Support for the new Power9 "XIVE" interrupt controller.
- TLB flushing optimisations for the radix MMU on Power9.
- Support for CAPI cards on Power9, using the "Coherent Accelerator Interface
Architecture 2.0".
- The ability to configure the mmap randomisation limits at build and runtime.
- Several small fixes and cleanups to the kprobes code, as well as support for
KPROBES_ON_FTRACE.
- Major improvements to handling of system reset interrupts, correctly treating
them as NMIs, giving them a dedicated stack and using a new hypervisor call
to trigger them, all of which should aid debugging and robustness.
Many fixes and other minor enhancements.
Thanks to:
Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan,
Aneesh Kumar K.V, Anshuman Khandual, Anton Blanchard, Balbir Singh, Ben
Hutchings, Benjamin Herrenschmidt, Bhupesh Sharma, Chris Packham, Christian
Zigotzky, Christophe Leroy, Christophe Lombard, Daniel Axtens, David Gibson,
Gautham R. Shenoy, Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli,
Hamish Martin, Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan,
Mahesh J Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew
R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran,
Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell Currey, Sukadev
Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C. Harding, Tyrel Datwyler,
Uma Krishnan, Vaibhav Jain, Vipin K Parashar, Yang Shi.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=vSF3
-----END PGP SIGNATURE-----
Merge tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Highlights include:
- Larger virtual address space on 64-bit server CPUs. By default we
use a 128TB virtual address space, but a process can request access
to the full 512TB by passing a hint to mmap().
- Support for the new Power9 "XIVE" interrupt controller.
- TLB flushing optimisations for the radix MMU on Power9.
- Support for CAPI cards on Power9, using the "Coherent Accelerator
Interface Architecture 2.0".
- The ability to configure the mmap randomisation limits at build and
runtime.
- Several small fixes and cleanups to the kprobes code, as well as
support for KPROBES_ON_FTRACE.
- Major improvements to handling of system reset interrupts,
correctly treating them as NMIs, giving them a dedicated stack and
using a new hypervisor call to trigger them, all of which should
aid debugging and robustness.
- Many fixes and other minor enhancements.
Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple,
Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton
Blanchard, Balbir Singh, Ben Hutchings, Benjamin Herrenschmidt,
Bhupesh Sharma, Chris Packham, Christian Zigotzky, Christophe Leroy,
Christophe Lombard, Daniel Axtens, David Gibson, Gautham R. Shenoy,
Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli, Hamish Martin,
Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mahesh J
Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew
R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver
O'Halloran, Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell
Currey, Sukadev Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C.
Harding, Tyrel Datwyler, Uma Krishnan, Vaibhav Jain, Vipin K Parashar,
Yang Shi"
* tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits)
powerpc/64s: Power9 has no LPCR[VRMASD] field so don't set it
powerpc/powernv: Fix TCE kill on NVLink2
powerpc/mm/radix: Drop support for CPUs without lockless tlbie
powerpc/book3s/mce: Move add_taint() later in virtual mode
powerpc/sysfs: Move #ifdef CONFIG_HOTPLUG_CPU out of the function body
powerpc/smp: Document irq enable/disable after migrating IRQs
powerpc/mpc52xx: Don't select user-visible RTAS_PROC
powerpc/powernv: Document cxl dependency on special case in pnv_eeh_reset()
powerpc/eeh: Clean up and document event handling functions
powerpc/eeh: Avoid use after free in eeh_handle_special_event()
cxl: Mask slice error interrupts after first occurrence
cxl: Route eeh events to all drivers in cxl_pci_error_detected()
cxl: Force context lock during EEH flow
powerpc/64: Allow CONFIG_RELOCATABLE if COMPILE_TEST
powerpc/xmon: Teach xmon oops about radix vectors
powerpc/mm/hash: Fix off-by-one in comment about kernel contexts ids
powerpc/pseries: Enable VFIO
powerpc/powernv: Fix iommu table size calculation hook for small tables
powerpc/powernv: Check kzalloc() return value in pnv_pci_table_alloc
powerpc: Add arch/powerpc/tools directory
...
Add override for lib.mk clean to fix the following warnings from clean
target run.
Makefile:63: warning: overriding recipe for target 'clean'
../lib.mk:55: warning: ignoring old recipe for target 'clean'
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
The changes to enable building with a separate output directory, in
commit a8ba798bc8 ("selftests: enable O and KBUILD_OUTPUT") broke
building the powerpc selftests on their own, eg:
$ cd tools/testing/selftests/powerpc; make
It was partially fixed in commit e53aff45c4 ("selftests: lib.mk Fix
individual test builds"), which defined OUTPUT for standalone tests. But
that only defines OUTPUT within the Makefile, the value is not exported
so sub-shells can't see it. We could export OUTPUT, but it's actually
cleaner to just expand the value of OUTPUT before we invoke the shell.
Fixes: a8ba798bc8 ("selftests: enable O and KBUILD_OUTPUT")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
There are repeated compiler flags "-Wall" in the Makefile.
The redundant compiler flag appears to have been there from the
introduction of the Makefile.
Signed-off-by: Chijun Sima <simachijun@qq.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This is a very basic test of the new cache shape AUXV entries. All it
does at the moment is look for the entries and error out if we don't
find all the ones we expect. Primarily intended for folks bringing up a
new chip to check that the cache info is making it all the way to
userspace correctly.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Refactor the AUXV routines so they are more composable. In a future test
we want to look for many AUXV entries and we don't want to have to read
/proc/self/auxv each time.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
On POWER8 (ISA 2.07) lxvx and stxvx are defined to be extended mnemonics
of lxvd2x and stxvd2x. For POWER9 (ISA 3.0) the HW architects in their
infinite wisdom made lxvx and stxvx instructions in their own right.
POWER9 aware GCC will use the POWER9 instruction for lxvx and stxvx
causing these selftests to fail on POWER8. Further compounding the
issue, because of the way -mvsx works it will cause the power9
instructions to be used regardless of -mcpu=power8 to GCC or -mpower8 to
AS.
The safest way to address the problem for now is to not use the extended
mnemonic. We don't care how the CPU loads the values from memory since
the tests only performs register comparisons, so using stdvd2x/lxvd2x
does not impact the test.
Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
Acked-by: Balbir Singh<bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Tests under alignment subdirectory are skipped when executed on previous
generation hardware, but harness still marks them as failed.
test: test_copy_unaligned
tags: git_version:unknown
[SKIP] Test skipped on line 26
skip: test_copy_unaligned
selftests: copy_unaligned [FAIL]
The MAGIC_SKIP_RETURN_VALUE value assigned to rc variable is retained till
the program exit which causes the test to be marked as failed.
This patch resets the value before returning to the main() routine.
With this patch the test o/p is as follows:
test: test_copy_unaligned
tags: git_version:unknown
[SKIP] Test skipped on line 26
skip: test_copy_unaligned
selftests: copy_unaligned [PASS]
Signed-off-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This update consists of:
-- fixes to several existing tests from Stafford Horne
-- cpufreq tests from Viresh Kumar
-- Selftest build and install fixes from Bamvor Jian Zhang
and Michael Ellerman
-- Fixes to protection-keys tests from Dave Hansen
-- Warning fixes from Shuah Khan
-----BEGIN PGP SIGNATURE-----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=F3yO
-----END PGP SIGNATURE-----
Merge tag 'linux-kselftest-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull Kselftest update from Shuah Khan:
"This update consists of:
- fixes to several existing tests from Stafford Horne
- cpufreq tests from Viresh Kumar
- Selftest build and install fixes from Bamvor Jian Zhang and Michael
Ellerman
- Fixes to protection-keys tests from Dave Hansen
- Warning fixes from Shuah Khan"
* tag 'linux-kselftest-4.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (28 commits)
selftests/powerpc: Fix remaining fallout from recent changes
selftests/powerpc: Fix the clean rule since recent changes
selftests: Fix the .S and .S -> .o rules
selftests: Fix the .c linking rule
selftests: Fix selftests build to just build, not run tests
selftests, x86, protection_keys: fix wrong offset in siginfo
selftests, x86, protection_keys: fix uninitialized variable warning
selftest: cpufreq: Update MAINTAINERS file
selftest: cpufreq: Add special tests
selftest: cpufreq: Add support to test cpufreq modules
selftest: cpufreq: Add suspend/resume/hibernate support
selftest: cpufreq: Add support for cpufreq tests
selftests: Add intel_pstate to TARGETS
selftests/intel_pstate: Update makefile to match new style
selftests/intel_pstate: Fix warning on loop index overflow
cpupower: Restore format of frequency-info limit
selftests/futex: Add headers to makefile dependencies
selftests/futex: Add stdio used for logging
selftests: x86 protection_keys remove dead code
selftests: x86 protection_keys fix unused variable compile warnings
...
In benchmarks we need to use $(TEST_GEN_PROGS) after we include lib.mk,
because lib.mk does the substitution to add $(OUTPUT).
In math the vmx and fpu names were typoed so they no longer matched
correctly, put back the 'v' and 'f'.
In tm we need to substitute $(OUTPUT) into SIGNAL_CONTEXT_CHK_TESTS so
that the rule matches.
In pmu there is an extraneous ':' on the end of $$BUILD_TARGET for the
clean and install rules, which breaks the logic in the child Makefiles.
Fixes: a8ba798bc8 ("selftests: enable O and KBUILD_OUTPUT")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
The clean rule is broken for the powerpc tests:
make[1]: Entering directory 'tools/testing/selftests/powerpc'
Makefile:63: warning: overriding recipe for target 'clean'
../lib.mk:51: warning: ignoring old recipe for target 'clean'
/bin/sh: 3: Syntax error: end of file unexpected (expecting "done")
Makefile:63: recipe for target 'clean' failed
Fixes: a8ba798bc8 ("selftests: enable O and KBUILD_OUTPUT")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Test uses PMC2 to count the event. But PMC1 is being initialized.
Patch to fix it.
Fixes: 3752e453f6 ('selftests/powerpc: Add tests of PMU EBBs')
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Enable O and KBUILD_OUTPUT for kselftest. User could compile kselftest
to another directory by passing O or KBUILD_OUTPUT. And O is high
priority than KBUILD_OUTPUT.
Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Some testcases need the clean extra data after running. This patch
introduce the "EXTRA_CLEAN" variable to address this requirement.
After KBUILD_OUTPUT is enabled in later patch, it will be easy to
decide to if we need do the cleanup in the KBUILD_OUTPUT path(if the
testcase ran immediately after compiled).
Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Currently, kselftest use TEST_PROGS, TEST_PROGS_EXTENDED, TEST_FILES to
indicate the test program, extended test program and test files. It is
easy to understand the purpose of these files. But mix of compiled and
uncompiled files lead to duplicated "all" and "clean" targets.
In order to remove the duplicated targets, introduce TEST_GEN_PROGS,
TEST_GEN_PROGS_EXTENDED, TEST_GEN_FILES to indicate the compiled
objects.
Also, the later patch will make use of TEST_GEN_XXX to redirect these
files to output directory indicated by KBUILD_OUTPUT or O.
And add this changes to "Contributing new tests(details)" of
Documentation/kselftest.txt.
Signed-off-by: Bamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
This patch adds ptrace interface test for TM SPR registers. This
also adds ptrace interface based helper functions related to TM
SPR registers access.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch adds ptrace interface test for VSX, VMX registers
inside TM context. This also adds ptrace interface based helper
functions related to chckpointed VSX, VMX registers access.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch adds ptrace interface test for VSX, VMX registers.
This also adds ptrace interface based helper functions related
to VSX, VMX registers access. This also adds some assembly
helper functions related to VSX and VMX registers.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch adds ptrace interface test for TAR, PPR, DSCR
registers inside TM context. This also adds ptrace
interface based helper functions related to checkpointed
TAR, PPR, DSCR register access.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch adds ptrace interface test for TAR, PPR, DSCR
registers. This also adds ptrace interface based helper
functions related to TAR, PPR, DSCR register access.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch adds ptrace interface test for GPR/FPR registers
inside suspended TM context.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch adds ptrace interface test for GPR/FPR registers
inside TM context. This adds ptrace interface based helper
functions related to checkpointed GPR/FPR access.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch adds ptrace interface test for GPR/FPR registers.
This adds ptrace interface based helper functions related to
GPR/FPR access and some assembly helper functions related to
GPR/FPR registers.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
[mpe: Add #defines for the new note types when headers don't define them]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
There are some functions, especially register related, which can
be shared across multiple selftests/powerpc test directories.
This patch creates a new include directory to store those shared
files, so that the file layout becomes more neat.
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
[mpe: Reworked to move the headers only]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch adds SPR number for TAR, PPR, DSCR special
purpose registers. It also adds TM, VSX, VMX related
instructions which will then be used by patches later
in the series.
Now that the new DSCR register definitions (SPRN_DSCR_PRIV and
SPRN_DSCR) are defined outside this directory, use them instead.
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Returning a negative value for a boolean function seem to have the
undesired effect of returning true. require_paranoia_below() is a
boolean function, but the variable used to store the return value is an
integer, receiving -1 or 0. This patch converts rc to bool, replaces -1
by false, and 0 by true.
mpe: This wasn't exhibiting in practice because the common case, where
we do the comparison of the desired level vs the current value, was
being compiled into a computation based on the result of the comparison,
ie. it wasn't using the default -1 value at all. However that was just
luck and the code is still wrong.
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Andrew Shadura <andrew.shadura@collabora.co.uk>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Load monitored won't be supported in POWER9, so PPC_FEATURE2_ARCH_3_00
(in HWCAP2) will no longer imply Load monitor support.
These Load monitored tests are enabled by PPC_FEATURE2_ARCH_3_00 so
they are now bogus and need to be removed.
This reverts commit 16c19a2e98 ("selftests/powerpc: Load Monitor
Register Tests").
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This halves the exception table size on 64-bit builds, and it allows
build-time sorting of exception tables to work on relocated kernels.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Minor asm fixups and bits to keep the selftests working]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This macro is taken from s390, and allows more flexibility in
changing exception table format.
mpe: Put it in ppc_asm.h and only define one version using
stringinfy_in_c(). Add some empty definitions and headers to keep the
selftests happy.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
If the result returned by load_unaligned_zeropad() doesn't match what we
expect we should fail the test!
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
If the load unaligned zeropad test takes a SEGV which can't be handled,
we increment segv_error, print the offending NIP and then return without
taking any further action. In almost all cases this means we'll just
take the SEGV again, and loop eternally spamming the console.
Instead just abort(), it's a fatal error in the test. The test harness
will notice that the child died and print a nice message for us.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Pull in a version of Anton's null_syscall benchmark:
http://ozlabs.org/~anton/junkcode/null_syscall.c
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Anton Blanchard <anton@au.ibm.com>
Signed-off-by: Rui Teng <rui.teng@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The changes to make EXPORT_SYMBOL work in asm, specifically commit
9445aa1a30 ("ppc: move exports to definitions"), in the kbuild tree,
breaks some of our selftests.
That is because we symlink the kernel code into the selftest, and shim
the required headers, and we are now missing asm/export.h
So create a minimal export.h to keep the tests building once powerpc and
the kbuild trees are merged.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>