Commit Graph

1779 Commits

Author SHA1 Message Date
Qiuhao Li
9d20f2af53 fuzz: set bits in operand of write/out to zero
Simplifying the crash cases by opportunistically setting bits in operands of
out/write to zero may help to debug, since usually bit one means turn on or
trigger a function while zero is the default turn-off setting.

Tested bug https://bugs.launchpad.net/qemu/+bug/1908062

Signed-off-by: Qiuhao Li <Qiuhao.Li@outlook.com>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <SYCPR01MB3502C84B6346A3E3DE708C7BFCAB0@SYCPR01MB3502.ausprd01.prod.outlook.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-01-11 14:59:21 +01:00
Qiuhao Li
247ab240c2 fuzz: remove IO commands iteratively
Now we use a one-time scan and remove strategy in the minimizer,
which is not suitable for timing dependent instructions.

For example, instruction A will indicate an address where the config
chunk locates, and instruction B will make the configuration active.
If we have the following instruction sequence:

...
A1
B1
A2
B2
...

A2 and B2 are the actual instructions that trigger the bug.

If we scan from top to bottom, after we remove A1, the behavior of B1
might be unknowable, including not to crash the program. But we will
successfully remove B1 later cause A2 and B2 will crash the process
anyway:

...
A1
A2
B2
...

Now one more trimming will remove A1.

In the perfect case, we would need to be able to remove A and B (or C!) at
the same time. But for now, let's just add a loop around the minimizer.

Since we only remove instructions, this iterative algorithm is converging.

Tested with Bug 1908062.

Signed-off-by: Qiuhao Li <Qiuhao.Li@outlook.com>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <SYCPR01MB350263004448040ACCB9A9F1FCAB0@SYCPR01MB3502.ausprd01.prod.outlook.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-01-11 14:59:21 +01:00
Qiuhao Li
e72203abec fuzz: split write operand using binary approach
Currently, we split the write commands' data from the middle. If it does not
work, try to move the pivot left by one byte and retry until there is no
space.

But, this method has two flaws:

1. It may fail to trim all unnecessary bytes on the right side.

For example, there is an IO write command:

  write addr uuxxxxuu

u is the unnecessary byte for the crash. Unlike ram write commands, in most
case, a split IO write won't trigger the same crash, So if we split from the
middle, we will get:

  write addr uu (will be removed in next round)
  write addr xxxxuu

For xxxxuu, since split it from the middle and retry to the leftmost byte
won't get the same crash, we will be stopped from removing the last two
bytes.

2. The algorithm complexity is O(n) since we move the pivot byte by byte.

To solve the first issue, we can try a symmetrical position on the right if
we fail on the left. As for the second issue, instead moving by one byte, we
can approach the boundary exponentially, achieving O(log(n)).

Give an example:

                   xxxxuu len=6
                        +
                        |
                        +
                 xxx,xuu 6/2=3 fail
                        +
         +--------------+-------------+
         |                            |
         +                            +
  xx,xxuu 6/2^2=1 fail         xxxxu,u 6-1=5 success
                                 +   +
         +------------------+----+   |
         |                  |        +-------------+ u removed
         +                  +
   xx,xxu 5/2=2 fail  xxxx,u 6-2=4 success
                           +
                           |
                           +-----------+ u removed

In some rare cases, this algorithm will fail to trim all unnecessary bytes:

  xxxxxxxxxuxxxxxx
  xxxxxxxx-xuxxxxxx Fail
  xxxx-xxxxxuxxxxxx Fail
  xxxxxxxxxuxx-xxxx Fail
  ...

I think the trade-off is worth it.

Signed-off-by: Qiuhao Li <Qiuhao.Li@outlook.com>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <SYCPR01MB3502D26F1BEB680CBBC169E5FCAB0@SYCPR01MB3502.ausprd01.prod.outlook.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-01-11 14:59:21 +01:00
Qiuhao Li
7b339f287f fuzz: double the IOs to remove for every loop
Instead of removing IO instructions one by one, we can try deleting multiple
instructions at once. According to the locality of reference, we double the
number of instructions to remove for the next round and recover it to one
once we fail.

This patch is usually significant for large input.

Test with quadrupled trace input at:
  https://bugs.launchpad.net/qemu/+bug/1890333/comments/1

Patched 1/6 version:
  real  0m45.904s
  user  0m16.874s
  sys   0m10.042s

Refined version:
  real  0m11.412s
  user  0m6.888s
  sys   0m3.325s

Signed-off-by: Qiuhao Li <Qiuhao.Li@outlook.com>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <SYCPR01MB350280A67BB55C3FADF173E3FCAB0@SYCPR01MB3502.ausprd01.prod.outlook.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-01-11 14:59:21 +01:00
Qiuhao Li
22ec0c696f fuzz: accelerate non-crash detection
We spend much time waiting for the timeout program during the minimization
process until it passes a time limit. This patch hacks the CLOSED (indicates
the redirection file closed) notification in QTest's output if it doesn't
crash.

Test with quadrupled trace input at:
  https://bugs.launchpad.net/qemu/+bug/1890333/comments/1

Original version:
  real	1m37.246s
  user	0m13.069s
  sys	0m8.399s

Refined version:
  real	0m45.904s
  user	0m16.874s
  sys	0m10.042s

Note:

Sometimes the mutated or the same trace may trigger a different crash
summary (second-to-last line) but indicates the same bug. For example, Bug
1910826 [1], which will trigger a stack overflow, may output summaries
like:

SUMMARY: AddressSanitizer: stack-overflow
/home/qiuhao/hack/qemu/build/../softmmu/physmem.c:488 in
flatview_do_translate

or

SUMMARY: AddressSanitizer: stack-overflow
(/home/qiuhao/hack/qemu/build/qemu-system-i386+0x27ca049) in __asan_memcpy

Etc.

If we use the whole summary line as the token, we may be prevented from
further minimization. So in this patch, we only use the first three words
which indicate the type of crash:

SUMMARY: AddressSanitizer: stack-overflow

[1] https://bugs.launchpad.net/qemu/+bug/1910826

Signed-off-by: Qiuhao Li <Qiuhao.Li@outlook.com>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Tested-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <SYCPR01MB350251DC04003450348FAF68FCAB0@SYCPR01MB3502.ausprd01.prod.outlook.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-01-11 14:59:21 +01:00
Peter Maydell
01b3e68bb1 scripts/coccinelle: New script to remove unnecessary timer_del() calls
Now that timer_free() implicitly calls timer_del(), sequences
  timer_del(mytimer);
  timer_free(mytimer);

can be simplified to just
  timer_free(mytimer);

Add a Coccinelle script to do this transformation.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201215154107.3255-3-peter.maydell@linaro.org
2021-01-08 15:13:38 +00:00
Stefan Hajnoczi
7fb48c0ee1 tracetool: show trace-events filename/lineno in fmt string errors
The compiler encounters trace event format strings in generated code.
Format strings are error-prone and therefore clear compiler errors are
important.

Use the #line directive to show the trace-events filename and line
number in format string errors:
https://gcc.gnu.org/onlinedocs/gcc-10.2.0/cpp/Line-Control.html

For example, if the cpu_in trace event's %u is changed to %p the
following error is reported:

  trace-events:29:18: error: format ‘%p’ expects argument of type ‘void *’, but argument 7 has type ‘unsigned int’ [-Werror=format=]

Line 29 in trace-events is where cpu_in is defined. This works for any
trace-events file in the QEMU source tree and the correct path is
displayed.

Unfortunately there does not seem to be a way to set the column, so "18"
is not the right character on that line.

Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200827142915.108730-5-stefanha@redhat.com>
2021-01-04 14:24:58 +00:00
Stefan Hajnoczi
4e66c9ef64 tracetool: add input filename and line number to Event
Store the input filename and line number in Event.

A later patch will use this to improve error messages.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200827142915.108730-4-stefanha@redhat.com>
2021-01-04 14:24:58 +00:00
Stefan Hajnoczi
294170c1dd tracetool: add out_lineno and out_next_lineno to out()
Make the output file line number and next line number available to
out().

A later patch will use this to improve error messages.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200827142915.108730-3-stefanha@redhat.com>
2021-01-04 14:24:58 +00:00
Stefan Hajnoczi
c05012a365 tracetool: add output filename command-line argument
The tracetool.py script writes to stdout. This means the output filename
is not available to the script. Add the output filename to the
command-line so that the script has access to the filename.

This also simplifies the tracetool.py invocation. It's no longer
necessary to use meson's custom_build(capture : true) to save output.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200827142915.108730-2-stefanha@redhat.com>
2021-01-04 14:24:58 +00:00
Vladimir Sementsov-Ogievskiy
cff6d3ca43 scripts/simplebench: add bench_prealloc.py
Benchmark for new preallocate filter.

Example usage:
    ./bench_prealloc.py ../../build/qemu-img \
        ssd-ext4:/path/to/mount/point \
        ssd-xfs:/path2 hdd-ext4:/path3 hdd-xfs:/path4

The benchmark shows performance improvement (or degradation) when use
new preallocate filter with qcow2 image.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201021145859.11201-22-vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00
Vladimir Sementsov-Ogievskiy
181f60c8c7 simplebench/results_to_text: make executable
Make results_to_text a tool to dump results saved in JSON file.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201021145859.11201-21-vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00
Vladimir Sementsov-Ogievskiy
aa362403f4 simplebench/results_to_text: add difference line to the table
Performance improvements / degradations are usually discussed in
percentage. Let's make the script calculate it for us.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201021145859.11201-20-vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
[mreitz: 'seconds' instead of 'secs']
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00
Vladimir Sementsov-Ogievskiy
96be1aeec7 simplebench/results_to_text: improve view of the table
Move to generic format for floats and percentage for error.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201021145859.11201-19-vsementsov@virtuozzo.com>
Acked-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00
Vladimir Sementsov-Ogievskiy
8e979febb0 simplebench: move results_to_text() into separate file
Let's keep view part in separate: this way it's better to improve it in
the following commits.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201021145859.11201-18-vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00
Vladimir Sementsov-Ogievskiy
bfccfa62ac simplebench: rename ascii() to results_to_text()
Next patch will use utf8 plus-minus symbol, let's use more generic (and
more readable) name.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201021145859.11201-17-vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00
Vladimir Sementsov-Ogievskiy
f52e1af0b0 scripts/simplebench: use standard deviation for +- error
Standard deviation is more usual to see after +- than current maximum
of deviations.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201021145859.11201-16-vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00
Vladimir Sementsov-Ogievskiy
4a44554a65 scripts/simplebench: support iops
Support benchmarks returning not seconds but iops. We'll use it for
further new test.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201021145859.11201-15-vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00
Vladimir Sementsov-Ogievskiy
270124e7ef scripts/simplebench: fix grammar: s/successed/succeeded/
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20201021145859.11201-14-vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2020-12-18 12:35:55 +01:00
Philippe Mathieu-Daudé
a1bcbb485c scripts/git.orderfile: Keep files with .inc extension sorted
Sort .inc files along with the extension including them.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20201213205132.243628-1-f4bug@amsat.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-15 12:53:16 -05:00
Marc-André Lureau
07b35a23c3 compiler.h: remove QEMU_GNUC_PREREQ
When needed, the G_GNUC_CHECK_VERSION() glib macro can be used instead.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20201210134752.780923-14-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-15 12:53:15 -05:00
Paolo Bonzini
953d0c333e scripts: kernel-doc: remove unnecessary change wrt Linux
A comment in kernel-doc mentions QEMU's qatomic_set macro, but since
this code originated in Linux we should just revert it and stay as close
to the kernel's copy of the script as possible.

The change was introduced (more or less unintentionally) in QEMU commit
commit d73415a315, which did a global search-and-replace of QEMU's
atomic access macros.

Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:25 -05:00
Mauro Carvalho Chehab
a1b8a57a0e scripts: kernel-doc: use :c:union when needed
Sphinx C domain code after 3.2.1 will start complaning if :c:struct
would be used for an union type:

	.../Documentation/gpu/drm-kms-helpers:352: ../drivers/video/hdmi.c:851: WARNING: C 'identifier' cross-reference uses wrong tag: reference name is 'union hdmi_infoframe' but found name is 'struct hdmi_infoframe'. Full reference name is 'union hdmi_infoframe'. Full found name is 'struct hdmi_infoframe'.

So, let's address this issue too in advance, in order to
avoid future issues.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/6e4ec3eec914df62389a299797a3880ae4490f35.1603791716.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-30-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:25 -05:00
Mauro Carvalho Chehab
e495a1b26c scripts: kernel-doc: split typedef complex regex
The typedef regex for function prototypes are very complex.
Split them into 3 separate regex and then join them using
qr.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/3a4af999a0d62d4ab9dfae1cdefdfcad93383356.1603792384.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-29-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:24 -05:00
Mauro Carvalho Chehab
01a7917d9b scripts: kernel-doc: fix typedef parsing
The include/linux/genalloc.h file defined this typedef:

	typedef unsigned long (*genpool_algo_t)(unsigned long *map,unsigned long size,unsigned long start,unsigned int nr,void *data, struct gen_pool *pool, unsigned long start_addr);

Because it has a type composite of two words (unsigned long),
the parser gets the typedef name wrong:

.. c:macro:: long

   **Typedef**: Allocation callback function type definition

Fix the regex in order to accept composite types when
defining a typedef for a function pointer.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/328e8018041cc44f7a1684e57f8d111230761c4f.1603792384.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-28-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:24 -05:00
Paolo Bonzini
3e72dc0135 Revert "kernel-doc: Handle function typedefs that return pointers"
This reverts commit 19ab6044be.
We will replace the commit with the fix from Linux.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-27-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:24 -05:00
Paolo Bonzini
47da500a7e Revert "kernel-doc: Handle function typedefs without asterisks"
This reverts commit 3cd3c5193c.
We will replace the commit with the fix from Linux.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-26-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:24 -05:00
Mauro Carvalho Chehab
ac3617d90c scripts: kernel-doc: try to use c:function if possible
There are a few namespace clashes by using c:macro everywhere:

basically, when using it, we can't have something like:

	.. c:struct:: pwm_capture

	.. c:macro:: pwm_capture

So, we need to use, instead:

	.. c:function:: int pwm_capture (struct pwm_device * pwm, struct pwm_capture * result, unsigned long timeout)

for the function declaration.

The kernel-doc change was proposed by Jakob Lykke Andersen here:

	6fd2076ec0

Although I did a different implementation.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-25-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:24 -05:00
Mauro Carvalho Chehab
4f5f16a193 scripts: kernel-doc: fix line number handling
Address several issues related to pointing to the wrong line
number:

1) ensure that line numbers will always be initialized

   When section is the default (Description), the line number
   is not initializing, producing this:

	$ ./scripts/kernel-doc --enable-lineno ./drivers/media/v4l2-core/v4l2-mem2mem.c|less

	**Description**

	#define LINENO 0
	In case of streamoff or release called on any context,
	1] If the context is currently running, then abort job will be called
	2] If the context is queued, then the context will be removed from
	   the job_queue

  Which is not right. Ensure that the line number will always
  be there. After applied, the result now points to the right location:

	**Description**

	#define LINENO 410
	In case of streamoff or release called on any context,
	1] If the context is currently running, then abort job will be called
	2] If the context is queued, then the context will be removed from
	   the job_queue

2) The line numbers for function prototypes are always + 1,
   because it is taken at the line after handling the prototype.
   Change the logic to point to the next line after the /** */
   block;

3) The "DOC:" line number should point to the same line as this
   markup is found, and not to the next one.

Probably part of the issues were due to a but that was causing
the line number offset to be incremented by one, if --export
were used.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-24-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:24 -05:00
Mauro Carvalho Chehab
486966e4a4 scripts: kernel-doc: allow passing desired Sphinx C domain dialect
When kernel-doc is called via kerneldoc.py, there's no need to
auto-detect the Sphinx version, as the Sphinx module already
knows it. So, add an optional parameter to allow changing the
Sphinx dialect.

As kernel-doc can also be manually called, keep the auto-detection
logic if the parameter was not specified. On such case, emit
a warning if sphinx-build can't be found at PATH.

I ended using a suggestion from Joe for using a more readable
regex, instead of using a complex one with a hidden group like:

	m/^(\d+)\.(\d+)(?:\.?(\d+)?)/

in order to get the optional <patch> argument.

Thanks-to: Joe Perches <joe@perches.com>
Suggested-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-23-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:23 -05:00
Mauro Carvalho Chehab
0c77185233 scripts: kernel-doc: don't mangle with parameter list
While kernel-doc needs to parse parameters in order to
identify its name, it shouldn't be touching the type,
as parsing it is very difficult, and errors happen.

One current error is when parsing this parameter:

	const u32 (*tab)[256]

Found at ./lib/crc32.c, on this function:

	u32 __pure crc32_be_generic (u32 crc, unsigned char const *p, size_t len, const u32 (*tab)[256], u32 polynomial);

The current logic mangles it, producing this output:

	const u32 ( *tab

That's something that it is not recognizeable.

So, instead, let's push the argument as-is, and use it
when printing the function prototype and when describing
each argument.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-22-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:23 -05:00
Mauro Carvalho Chehab
3999ffcf13 scripts: kernel-doc: fix typedef identification
Some typedef expressions are output as normal functions.

As we need to be clearer about the type with Sphinx 3.x,
detect such cases.

While here, fix a wrongly-indented block.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-21-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:23 -05:00
Mauro Carvalho Chehab
78c8c92c5d scripts: kernel-doc: reimplement -nofunction argument
Right now, the build system doesn't use -nofunction, as
it is pretty much useless, because it doesn't consider
the other output modes (extern, internal), working only
with all.

Also, it is limited to exclude functions.

Re-implement it in order to allow excluding any symbols from
the document output, no matter what mode is used.

The parameter was also renamed to "-nosymbol", as it express
better its meaning.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-20-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:23 -05:00
Mauro Carvalho Chehab
5abfaa6a7f scripts: kernel-doc: fix troubles with line counts
There's currently a bug with the way kernel-doc script
counts line numbers that can be seen with:

	$ ./scripts/kernel-doc -rst  -enable-lineno include/linux/math64.h >all && ./scripts/kernel-doc -rst -internal -enable-lineno include/linux/math64.h >int && diff -U0 int all

	--- int	2020-09-28 12:58:08.927486808 +0200
	+++ all	2020-09-28 12:58:08.905486845 +0200
	@@ -1 +1 @@
	-#define LINENO 27
	+#define LINENO 26
	@@ -3 +3 @@
	-#define LINENO 16
	+#define LINENO 15
	@@ -9 +9 @@
	-#define LINENO 17
	+#define LINENO 16
	...

This is happening with perl version 5.30.3, but I'm not
so sure if this is a perl bug, or if this is due to something
else.

In any case, fixing it is easy. Basically, when "-internal"
parameter is used, the process_export_file() function opens the
handle "IN". This makes the line number to be incremented, as the
handler for the main open is also "IN".

Fix the problem by using a different handler for the
main open().

While here, add a missing close for it.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-19-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:23 -05:00
Mauro Carvalho Chehab
60ef7c1801 scripts: kernel-doc: use a less pedantic markup for funcs on Sphinx 3.x
Unfortunately, Sphinx 3.x parser for c functions is too pedantic:

	https://github.com/sphinx-doc/sphinx/issues/8241

While it could be relaxed with some configurations, there are
several corner cases that it would make it hard to maintain,
and will require teaching conf.py about several macros.

So, let's instead use the :c:macro notation. This will
produce an output that it is not as nice as currently, but it
should still be acceptable, and will provide cross-references,
removing thousands of warnings when building with newer
versions of Sphinx.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-18-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:22 -05:00
Mauro Carvalho Chehab
6d3a3cfc2f scripts: kernel-doc: make it more compatible with Sphinx 3.x
With Sphinx 3.x, the ".. c:type:" tag was changed to accept either:

	.. c:type:: typedef-like declaration
	.. c:type:: name

Using it for other types (including functions) don't work anymore.

So, there are newer tags for macro, enum, struct, union, and others,
which doesn't exist on older versions.

Add a check for the Sphinx version and change the produced tags
accordingly.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-17-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:22 -05:00
Paolo Bonzini
46ae6e8f82 Revert "kernel-doc: Use c:struct for Sphinx 3.0 and later"
This reverts commit 152d1967f6.
We will replace the commit with the fix from Linux.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-16-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:22 -05:00
Paolo Bonzini
a832c9844d Revert "scripts/kerneldoc: For Sphinx 3 use c:macro for macros with arguments"
This reverts commit 92bb29f9b2.
We will replace the commit with the fix from Linux.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-15-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:22 -05:00
Mauro Carvalho Chehab
306b015cfb scripts: kernel-doc: add support for typedef enum
The PHY kernel-doc markup has gained support for documenting
a typedef enum.

However, right now the parser was not prepared for it.

So, add support for parsing it.

Fixes: 4069a572d423 ("net: phy: Document core PHY structures")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-14-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:22 -05:00
Jonathan Cameron
5c51f435cb kernel-doc: add support for ____cacheline_aligned attribute
Subroutine dump_struct uses type attributes to check if the struct
syntax is valid. Then, it removes all attributes before using it for
output. `____cacheline_aligned` is an attribute that is
not included in both steps. Add it, since it is used by kernel structs.

Based on previous patch to add ____cacheline_aligned_in_smp.
Motivated by patches to reorder this attribute to before the
variable name.   Whilst we could do that in all cases, that would
be a massive change and it is more common in the kernel to place
this particular attribute after the variable name. A quick grep
suggests approximately 400 instances of which 341 have this
attribute just before a semicolon and hence after the variable name.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20200910185415.653139-1-jic23@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-13-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:21 -05:00
Mauro Carvalho Chehab
697f668ad1 kernel-doc: include line numbers for function prototypes
This should solve bad error reports like this one:

	./include/linux/iio/iio.h:0: WARNING: Unknown target name: "devm".

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/56eed0ba50cd726236acd12b11b55ce54854c5ea.1599660067.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-12-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:21 -05:00
Pierre-Louis Bossart
86cba21743 scripts/kernel-doc: optionally treat warnings as errors
The kbuild bot recently added the W=1 option, which triggered
documentation cleanups to squelch hundreds of kernel-doc warnings.

To make sure new kernel contributions don't add regressions to
kernel-doc descriptors, this patch suggests an option to treat
warnings as errors in CI/automated tests.

A -Werror command-line option is added to the kernel-doc script. When
this option is set, the script will return the number of warnings
found. The caller can then treat this positive return value as an
error and stop the build.

Using this command line option is however not straightforward when the
kernel-doc script is called from other scripts. To align with typical
kernel compilation or documentation generation, the Werror option is
also set by checking the KCFLAGS environment variable, or if
KDOC_WERROR is defined, as in the following examples:

KCFLAGS="-Wall -Werror" make W=1 sound/
KCFLAGS="-Wall -Werror" make W=1 drivers/soundwire/
KDOC_WERROR=1 make htmldocs

Note that in the last example the documentation build does not stop,
only an additional log is provided.

Credits to Randy Dunlap for suggesting the use of environment variables.

Suggested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200728162040.92467-1-pierre-louis.bossart@linux.intel.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-11-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:21 -05:00
Mauro Carvalho Chehab
2552f59a34 scripts/kernel-doc: handle function pointer prototypes
There are some function pointer prototypes inside the net
includes, like this one:

	int (*pcs_config)(struct phylink_config *config, unsigned int mode,
			  phy_interface_t interface, const unsigned long *advertising);

There's nothing wrong using it with kernel-doc, but we need to
add a rule for it to parse such kind of prototype.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/fec520dd731a273013ae06b7653a19c7d15b9562.1592895969.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-10-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:21 -05:00
Mauro Carvalho Chehab
f0fd307d25 scripts/kernel-doc: parse __ETHTOOL_DECLARE_LINK_MODE_MASK
The __ETHTOOL_DECLARE_LINK_MODE_MASK macro is a variant of
DECLARE_BITMAP(), used by phylink.h. As we have already a
parser for DECLARE_BITMAP(), let's add one for this macro,
in order to avoid such warnings:

	./include/linux/phylink.h:54: warning: Function parameter or member '__ETHTOOL_DECLARE_LINK_MODE_MASK(advertising' not described in 'phylink_link_state'
	./include/linux/phylink.h:54: warning: Function parameter or member '__ETHTOOL_DECLARE_LINK_MODE_MASK(lp_advertising' not described in 'phylink_link_state'

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/d1d1dea67a28117c0b0c33271b139c4455fef287.1592895969.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-9-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:21 -05:00
Alexander A. Klimov
cd08b80952 Replace HTTP links with HTTPS ones: documentation
Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.

Deterministic algorithm:
For each file:
  For each line:
    If doesn't contain `\bxmlns\b`:
      For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
        If both the HTTP and HTTPS versions
        return 200 OK and serve the same content:
          Replace HTTP with HTTPS.

Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Link: https://lore.kernel.org/r/20200526060544.25127-1-grandmaster@al2klimov.de
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-8-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:21 -05:00
Mauro Carvalho Chehab
9f2b463ad8 scripts: kernel-doc: accept blank lines on parameter description
Sphinx is very pedantic with respect to blank lines. Sometimes,
in order to make it to properly handle something, we need to
add a blank line. However, currently, any blank line inside a
kernel-doc comment like:

	/*
	 * @foo: bar
         *
	 *       foobar
	 *
	 * some description

will be considered as if "foobar" was part of the description.

This patch changes kernel-doc behavior. After it, foobar will
be considered as part of the parameter text. The description
will only be considered as such if it starts with:

zero spaces after asterisk:

	*foo

one space after asterisk:
	* foo

or have a explicit Description section:

	*   Description:

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/c07d2862792d75a2691d69c9eceb7b89a0164cc0.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-7-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:20 -05:00
Mauro Carvalho Chehab
b1e8e720b6 scripts: kernel-doc: accept negation like !@var
On a few places, it sometimes need to indicate a negation of a
parameter, like:

	!@fshared

This pattern happens, for example, at:

	kernel/futex.c

and it is perfectly valid. However, kernel-doc currently
transforms it into:

	!**fshared**

This won't do what it would be expected.

Fortunately, fixing the script is a simple matter of storing
the "!" before "@" and adding it after the bold markup, like:

	**!fshared**

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/0314b47f8c3e1f9db00d5375a73dc3cddd8a21f2.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-6-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:20 -05:00
Mauro Carvalho Chehab
76083982a5 scripts: kernel-doc: proper handle @foo->bar()
The pattern @foo->bar() is valid, as it can be used by a
function pointer inside a struct passed as a parameter.

Right now, it causes a warning:

	./drivers/firewire/core-transaction.c:606: WARNING: Inline strong start-string without end-string.

In this specific case, the kernel-doc markup is:

	/**
	 * fw_core_remove_address_handler() - unregister an address handler
	 * @handler: callback
	 *
	 * To be called in process context.
	 *
	 * When fw_core_remove_address_handler() returns, @handler->callback() is
	 * guaranteed to not run on any CPU anymore.
	 */

With seems valid on my eyes. So, instead of trying to hack
the kernel-doc markup, let's teach it about how to handle
such things. This should likely remove lots of other similar
warnings as well.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/48b46426d7bf6ff7529f20e5718fbf4e9758e62c.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-5-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:20 -05:00
Jonathan Neuschäfer
65fb67bf73 scripts/kernel-doc: Add support for named variable macro arguments
Currently, when kernel-doc encounters a macro with a named variable
argument[1], such as this:

   #define hlist_for_each_entry_rcu(pos, head, member, cond...)

... it expects the variable argument to be documented as `cond...`,
rather than `cond`. This is semantically wrong, because the name (as
used in the macro body) is actually `cond`.

With this patch, kernel-doc will accept the name without dots (`cond`
in the example above) in doc comments, and warn if the name with dots
(`cond...`) is used and verbose mode[2] is enabled.

The support for the `cond...` syntax can be removed later, when the
documentation of all such macros has been switched to the new syntax.

Testing this patch on top of v5.4-rc6, `make htmldocs` shows a few
changes in log output and HTML output:

 1) The following warnings[3] are eliminated:

   ./include/linux/rculist.h:374: warning:
        Excess function parameter 'cond' description in 'list_for_each_entry_rcu'
   ./include/linux/rculist.h:651: warning:
        Excess function parameter 'cond' description in 'hlist_for_each_entry_rcu'

 2) For list_for_each_entry_rcu and hlist_for_each_entry_rcu, the
    correct description is shown

 3) Named variable arguments are shown without dots

[1]: https://gcc.gnu.org/onlinedocs/cpp/Variadic-Macros.html
[2]: scripts/kernel-doc -v
[3]: See also https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git/commit/?h=dev&id=5bc4bc0d6153617eabde275285b7b5a8137fdf3c

Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-4-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:20 -05:00
André Almeida
b5a8dfb532 kernel-doc: add support for ____cacheline_aligned_in_smp attribute
Subroutine dump_struct uses type attributes to check if the struct
syntax is valid. Then, it removes all attributes before using it for
output. `____cacheline_aligned_in_smp` is an attribute that is
not included in both steps. Add it, since it is used by kernel structs.

Signed-off-by: André Almeida <andrealmeid@collabora.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20201117165312.118257-3-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-12-10 12:15:20 -05:00