Commit Graph

26 Commits

Author SHA1 Message Date
Christophe Leroy
69d4d6e5fd powerpc: Don't use 'struct ppc_inst' to reference instruction location
'struct ppc_inst' is an internal representation of an instruction, but
in-memory instructions are and will remain a table of 'u32' forever.

Replace all 'struct ppc_inst *' used for locating an instruction in
memory by 'u32 *'. This removes a lot of undue casts to 'struct
ppc_inst *'.

It also helps locating ab-use of 'struct ppc_inst' dereference.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Fix ppc_inst_next(), use u32 instead of unsigned int]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7062722b087228e42cbd896e39bfdf526d6a340a.1621516826.git.christophe.leroy@csgroup.eu
2021-06-17 00:09:00 +10:00
Christophe Leroy
5a03e1e972 powerpc/ftrace: Use PPC_RAW_MFLR() and PPC_RAW_NOP()
Use PPC_RAW_MFLR() instead of open coding with PPC_INST_MFLR.

Same for PPC_INST_NOP.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/98fd4d717810b7c4032a1edf62dd6fe638e64329.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:48 +10:00
Christophe Leroy
8804d5beef powerpc/lib/code-patching: Use PPC_RAW_() macros
Instead of open coding with PPC_INST_ defines, use
PPC_RAW_() macros. It improves readability.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/8c92f1d9e825ee47c6f88fe43ad42d2a8cc2ab4a.1621506159.git.christophe.leroy@csgroup.eu
2021-06-16 00:16:47 +10:00
Christophe Leroy
41d6cf68b5 powerpc: Rename probe_kernel_read_inst()
When probe_kernel_read_inst() was created, it was to mimic
probe_kernel_read() function.

Since then, probe_kernel_read() has been renamed
copy_from_kernel_nofault().

Rename probe_kernel_read_inst() into copy_inst_from_kernel_nofault().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b783d1f7cdb8914992384a669a2af57051b6bdcf.1618405715.git.christophe.leroy@csgroup.eu
2021-04-21 22:52:33 +10:00
Jordan Niethe
50428fdc53 powerpc: Add a ppc_inst_as_str() helper
There are quite a few places where instructions are printed, this is
done using a '%x' format specifier. With the introduction of prefixed
instructions, this does not work well. Currently in these places,
ppc_inst_val() is used for the value for %x so only the first word of
prefixed instructions are printed.

When the instructions are word instructions, only a single word should
be printed. For prefixed instructions both the prefix and suffix should
be printed. To accommodate both of these situations, instead of a '%x'
specifier use '%s' and introduce a helper, __ppc_inst_as_str() which
returns a char *. The char * __ppc_inst_as_str() returns is buffer that
is passed to it by the caller.

It is cumbersome to require every caller of __ppc_inst_as_str() to now
declare a buffer. To make it more convenient to use __ppc_inst_as_str(),
wrap it in a macro that uses a compound statement to allocate a buffer
on the caller's stack before calling it.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
[mpe: Drop 0x prefix to match most existings uses, especially xmon]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200602052728.18227-1-jniethe5@gmail.com
2020-07-23 17:41:36 +10:00
Christoph Hellwig
fe557319aa maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault
Better describe what these functions do.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-17 10:57:41 -07:00
Jordan Niethe
95b980a00d powerpc: Add a probe_kernel_read_inst() function
Introduce a probe_kernel_read_inst() function to use in cases where
probe_kernel_read() is used for getting an instruction. This will be
more useful for prefixed instructions.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
[mpe: Don't write to *inst on error]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-15-jniethe5@gmail.com
2020-05-19 00:10:37 +10:00
Jordan Niethe
f8faaffaa7 powerpc: Use a function for reading instructions
Prefixed instructions will mean there are instructions of different
length. As a result dereferencing a pointer to an instruction will not
necessarily give the desired result. Introduce a function for reading
instructions from memory into the instruction data type.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-13-jniethe5@gmail.com
2020-05-19 00:10:37 +10:00
Jordan Niethe
94afd069d9 powerpc: Use a datatype for instructions
Currently unsigned ints are used to represent instructions on powerpc.
This has worked well as instructions have always been 4 byte words.

However, ISA v3.1 introduces some changes to instructions that mean
this scheme will no longer work as well. This change is Prefixed
Instructions. A prefixed instruction is made up of a word prefix
followed by a word suffix to make an 8 byte double word instruction.
No matter the endianness of the system the prefix always comes first.
Prefixed instructions are only planned for powerpc64.

Introduce a ppc_inst type to represent both prefixed and word
instructions on powerpc64 while keeping it possible to exclusively
have word instructions on powerpc32.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Fix compile error in emulate_spe()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-12-jniethe5@gmail.com
2020-05-19 00:10:37 +10:00
Jordan Niethe
217862d9b9 powerpc: Introduce functions for instruction equality
In preparation for an instruction data type that can not be directly
used with the '==' operator use functions for checking equality.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Balamuruhan S <bala24@linux.ibm.com>
Link: https://lore.kernel.org/r/20200506034050.24806-11-jniethe5@gmail.com
2020-05-19 00:10:37 +10:00
Jordan Niethe
777e26f0ed powerpc: Use an accessor for instructions
In preparation for introducing a more complicated instruction type to
accommodate prefixed instructions use an accessor for getting an
instruction as a u32.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-8-jniethe5@gmail.com
2020-05-19 00:10:36 +10:00
Jordan Niethe
7534625128 powerpc: Use a macro for creating instructions from u32s
In preparation for instructions having a more complex data type start
using a macro, ppc_inst(), for making an instruction out of a u32.  A
macro is used so that instructions can be used as initializer elements.
Currently this does nothing, but it will allow for creating a data type
that can represent prefixed instructions.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Change include guard to _ASM_POWERPC_INST_H]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-7-jniethe5@gmail.com
2020-05-19 00:10:36 +10:00
Jordan Niethe
7c95d8893f powerpc: Change calling convention for create_branch() et. al.
create_branch(), create_cond_branch() and translate_branch() return the
instruction that they create, or return 0 to signal an error. Separate
these concerns in preparation for an instruction type that is not just
an unsigned int.  Fill the created instruction to a pointer passed as
the first parameter to the function and use a non-zero return value to
signify an error.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Alistair Popple <alistair@popple.id.au>
Link: https://lore.kernel.org/r/20200506034050.24806-6-jniethe5@gmail.com
2020-05-19 00:10:36 +10:00
Naveen N. Rao
370011a270 powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
This associates entries in the ftrace_ret_stack with corresponding stack
frames, enabling more robust stack unwinding. Also update the only user
of ftrace_graph_ret_addr() to pass the stack pointer.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0224f2d0971b069c678e2ff678cfc2cd1e114cfe.1567707399.git.naveen.n.rao@linux.vnet.ibm.com
2019-09-18 12:24:55 +10:00
Christophe Leroy
7f9c929a7f powerpc: Move PPC_HA() PPC_HI() and PPC_LO() to ppc-opcode.h
PPC_HA() PPC_HI() and PPC_LO() macros are nice macros. Move them
from module64.c to ppc-opcode.h in order to use them in other places.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Clean up formatting in new code, drop duplicates in ftrace.c]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-07-06 00:29:50 +10:00
Michael Ellerman
7bea7ac0ca powerpc/syscalls: Fix syscall tracing
Recently in commit fbf508da74 ("powerpc: split compat syscall table
out from native table") we changed the layout of the system call
table. Instead of having two entries for each syscall number, one for
the regular entry point and one for the compat entry point, we now
have separate tables for regular and compat entry points.

This inadvertently broke syscall tracing (CONFIG_FTRACE_SYSCALLS),
because our implementation of arch_syscall_addr() knew about the
layout of the table (it did nr * 2).

We can fix it just by dropping our version of arch_syscall_addr() and
using the generic version which does:

	return (unsigned long)sys_call_table[nr];

Fixes: fbf508da74 ("powerpc: split compat syscall table out from native table")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-01-15 21:32:25 +11:00
Linus Torvalds
8d6973327e powerpc updates for 4.21
Notable changes:
 
  - Mitigations for Spectre v2 on some Freescale (NXP) CPUs.
 
  - A large series adding support for pass-through of Nvidia V100 GPUs to guests
    on Power9.
 
  - Another large series to enable hardware assistance for TLB table walk on
    MPC8xx CPUs.
 
  - Some preparatory changes to our DMA code, to make way for further cleanups
    from Christoph.
 
  - Several fixes for our Transactional Memory handling discovered by fuzzing the
    signal return path.
 
  - Support for generating our system call table(s) from a text file like other
    architectures.
 
  - A fix to our page fault handler so that instead of generating a WARN_ON_ONCE,
    user accesses of kernel addresses instead print a ratelimited and
    appropriately scary warning.
 
  - A cosmetic change to make our unhandled page fault messages more similar to
    other arches and also more compact and informative.
 
  - Freescale updates from Scott:
    "Highlights include elimination of legacy clock bindings use from dts
     files, an 83xx watchdog handler, fixes to old dts interrupt errors, and
     some minor cleanup."
 
 And many clean-ups, reworks and minor fixes etc.
 
 Thanks to:
  Alexandre Belloni, Alexey Kardashevskiy, Andrew Donnellan, Aneesh Kumar K.V,
  Arnd Bergmann, Benjamin Herrenschmidt, Breno Leitao, Christian Lamparter,
  Christophe Leroy, Christoph Hellwig, Daniel Axtens, Darren Stevens, David
  Gibson, Diana Craciun, Dmitry V. Levin, Firoz Khan, Geert Uytterhoeven, Greg
  Kurz, Gustavo Romero, Hari Bathini, Joel Stanley, Kees Cook, Madhavan
  Srinivasan, Mahesh Salgaonkar, Markus Elfring, Mathieu Malaterre, Michal
  Suchánek, Naveen N. Rao, Nick Desaulniers, Oliver O'Halloran, Paul Mackerras,
  Ram Pai, Ravi Bangoria, Rob Herring, Russell Currey, Sabyasachi Gupta, Sam
  Bobroff, Satheesh Rajendran, Scott Wood, Segher Boessenkool, Stephen Rothwell,
  Tang Yuantian, Thiago Jung Bauermann, Yangtao Li, Yuantian Tang, Yue Haibing.
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Merge tag 'powerpc-4.21-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - Mitigations for Spectre v2 on some Freescale (NXP) CPUs.

   - A large series adding support for pass-through of Nvidia V100 GPUs
     to guests on Power9.

   - Another large series to enable hardware assistance for TLB table
     walk on MPC8xx CPUs.

   - Some preparatory changes to our DMA code, to make way for further
     cleanups from Christoph.

   - Several fixes for our Transactional Memory handling discovered by
     fuzzing the signal return path.

   - Support for generating our system call table(s) from a text file
     like other architectures.

   - A fix to our page fault handler so that instead of generating a
     WARN_ON_ONCE, user accesses of kernel addresses instead print a
     ratelimited and appropriately scary warning.

   - A cosmetic change to make our unhandled page fault messages more
     similar to other arches and also more compact and informative.

   - Freescale updates from Scott:
       "Highlights include elimination of legacy clock bindings use from
        dts files, an 83xx watchdog handler, fixes to old dts interrupt
        errors, and some minor cleanup."

  And many clean-ups, reworks and minor fixes etc.

  Thanks to: Alexandre Belloni, Alexey Kardashevskiy, Andrew Donnellan,
  Aneesh Kumar K.V, Arnd Bergmann, Benjamin Herrenschmidt, Breno Leitao,
  Christian Lamparter, Christophe Leroy, Christoph Hellwig, Daniel
  Axtens, Darren Stevens, David Gibson, Diana Craciun, Dmitry V. Levin,
  Firoz Khan, Geert Uytterhoeven, Greg Kurz, Gustavo Romero, Hari
  Bathini, Joel Stanley, Kees Cook, Madhavan Srinivasan, Mahesh
  Salgaonkar, Markus Elfring, Mathieu Malaterre, Michal Suchánek, Naveen
  N. Rao, Nick Desaulniers, Oliver O'Halloran, Paul Mackerras, Ram Pai,
  Ravi Bangoria, Rob Herring, Russell Currey, Sabyasachi Gupta, Sam
  Bobroff, Satheesh Rajendran, Scott Wood, Segher Boessenkool, Stephen
  Rothwell, Tang Yuantian, Thiago Jung Bauermann, Yangtao Li, Yuantian
  Tang, Yue Haibing"

* tag 'powerpc-4.21-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (201 commits)
  Revert "powerpc/fsl_pci: simplify fsl_pci_dma_set_mask"
  powerpc/zImage: Also check for stdout-path
  powerpc: Fix HMIs on big-endian with CONFIG_RELOCATABLE=y
  macintosh: Use of_node_name_{eq, prefix} for node name comparisons
  ide: Use of_node_name_eq for node name comparisons
  powerpc: Use of_node_name_eq for node name comparisons
  powerpc/pseries/pmem: Convert to %pOFn instead of device_node.name
  powerpc/mm: Remove very old comment in hash-4k.h
  powerpc/pseries: Fix node leak in update_lmb_associativity_index()
  powerpc/configs/85xx: Enable CONFIG_DEBUG_KERNEL
  powerpc/dts/fsl: Fix dtc-flagged interrupt errors
  clk: qoriq: add more compatibles strings
  powerpc/fsl: Use new clockgen binding
  powerpc/83xx: handle machine check caused by watchdog timer
  powerpc/fsl-rio: fix spelling mistake "reserverd" -> "reserved"
  powerpc/fsl_pci: simplify fsl_pci_dma_set_mask
  arch/powerpc/fsl_rmu: Use dma_zalloc_coherent
  vfio_pci: Add NVIDIA GV100GL [Tesla V100 SXM2] subdriver
  vfio_pci: Allow regions to add own capabilities
  vfio_pci: Allow mapping extra regions
  ...
2018-12-27 10:43:24 -08:00
Steven Rostedt (VMware)
fe60522ec6 powerpc/function_graph: Simplify with function_graph_enter()
The function_graph_enter() function does the work of calling the function
graph hook function and the management of the shadow stack, simplifying the
work done in the architecture dependent prepare_ftrace_return().

Have powerpc use the new code, and remove the shadow stack management as well as
having to set up the trace structure.

This is needed to prepare for a fix of a design bug on how the curr_ret_stack
is used.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: stable@kernel.org
Fixes: 03274a3ffb ("tracing/fgraph: Adjust fgraph depth before calling trace return callback")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-27 20:31:02 -05:00
YueHaibing
d64cf54e89 powerpc64/ftrace: Drop pointless static qualifier in is_b_op()
There is no need to have the 'intoffset' variable static since new value
always be assigned before use it.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-11-25 17:11:22 +11:00
Naveen N. Rao
67361cf807 powerpc/ftrace: Handle large kernel configs
Currently, we expect to be able to reach ftrace_caller() from all
ftrace-enabled functions through a single relative branch. With large
kernel configs, we see functions outside of 32MB of ftrace_caller()
causing ftrace_init() to bail.

In such configurations, gcc/ld emits two types of trampolines for mcount():
1. A long_branch, which has a single branch to mcount() for functions that
   are one hop away from mcount():
	c0000000019e8544 <00031b56.long_branch._mcount>:
	c0000000019e8544:	4a 69 3f ac 	b       c00000000007c4f0 <._mcount>

2. A plt_branch, for functions that are farther away from mcount():
	c0000000051f33f8 <0008ba04.plt_branch._mcount>:
	c0000000051f33f8:	3d 82 ff a4 	addis   r12,r2,-92
	c0000000051f33fc:	e9 8c 04 20 	ld      r12,1056(r12)
	c0000000051f3400:	7d 89 03 a6 	mtctr   r12
	c0000000051f3404:	4e 80 04 20 	bctr

We can reuse those trampolines for ftrace if we can have those
trampolines go to ftrace_caller() instead. However, with ABIv2, we
cannot depend on r2 being valid. As such, we use only the long_branch
trampolines by patching those to instead branch to ftrace_caller or
ftrace_regs_caller.

In addition, we add additional trampolines around .text and .init.text
to catch locations that are covered by the plt branches. This allows
ftrace to work with most large kernel configurations.

For now, we always patch the trampolines to go to ftrace_regs_caller,
which is slightly inefficient. This can be optimized further at a later
point.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-20 13:26:47 +11:00
Nicholas Piggin
abba759796 powerpc/kbuild: move -mprofile-kernel check to Kconfig
This eliminates the workaround that requires disabling
-mprofile-kernel by default in Kconfig.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-06-11 09:16:29 +09:00
Michael Ellerman
0c0c52306f powerpc: Only support DYNAMIC_FTRACE not static
We've had dynamic ftrace support for over 9 years since Steve first
wrote it, all the distros use dynamic, and static is basically
untested these days, so drop support for static ftrace.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-03 22:32:29 +10:00
Naveen N. Rao
ae30cc05be powerpc64/ftrace: Implement support for ftrace_regs_caller()
With -mprofile-kernel, we always save the full register state in
ftrace_caller(). While this works, this is inefficient if we're not
interested in the register state, such as when we're using the function
tracer.

Rename the existing ftrace_caller() as ftrace_regs_caller() and provide
a simpler implementation for ftrace_caller() that is used when registers
are not required to be saved.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-03 22:32:29 +10:00
Naveen N. Rao
9ef4042364 powerpc64/ftrace: Use the generic version of ftrace_replace_code()
Our implementation matches that of the generic version, which also
handles FTRACE_UPDATE_MODIFY_CALL. So, remove our implementation in
favor of the generic version.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-05-03 22:32:28 +10:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
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>
2017-11-02 11:10:55 +01:00
Naveen N. Rao
7853f9c029 powerpc: Split ftrace bits into a separate file
entry_*.S now includes a lot more than just kernel entry/exit code. As a
first step at cleaning this up, let's split out the ftrace bits into
separate files. Also move all related tracing code into a new trace/
subdirectory.

No functional changes.

Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-27 22:20:29 +10:00