linux-stable.git/tools/testing/selftests/vm, branch v5.10

userfaultfd: selftests: fix SIGSEGV if huge mmap fails

2020-12-06T18:19:07+00:00

The error handling in hugetlb_allocate_area() was incorrect for the
hugetlb_shared test case.

Previously the behavior was:

- mmap a hugetlb area
  - If this fails, set the pointer to NULL, and carry on
- mmap an alias of the same hugetlb fd
  - If this fails, munmap the original area

If the original mmap failed, it's likely the second one did too.  If
both failed, we'd blindly try to munmap a NULL pointer, causing a
SIGSEGV.  Instead, "goto fail" so we return before trying to mmap the
alias.

This issue can be hit "in real life" by forgetting to set
/proc/sys/vm/nr_hugepages (leaving it at 0), and then trying to run the
hugetlb_shared test.

Another small improvement is, when the original mmap fails, don't just
print "it failed": perror(), so we can see *why*.  :)

Signed-off-by: Axel Rasmussen 
Signed-off-by: Andrew Morton 
Cc: Shuah Khan 
Cc: Peter Xu 
Cc: Joe Perches 
Cc: Mike Rapoport 
Cc: Andrea Arcangeli 
Cc: David Alan Gilbert 
Link: https://lkml.kernel.org/r/20201204203443.2714693-1-axelrasmussen@google.com
Signed-off-by: Linus Torvalds

tools/testing/selftests/vm: fix build error

2020-12-06T18:19:07+00:00

Only x86 and PowerPC implement the pkey-xxx.h, and an error was reported
when compiling protection_keys.c.

Add a Arch judgment to compile "protection_keys" in the Makefile.

If other arch implement this, add the arch name to the Makefile.
eg:
    ifneq (,$(findstring $(ARCH),powerpc mips ... ))

Following build errors:

    pkey-helpers.h:93:2: error: #error Architecture not supported
     #error Architecture not supported
    pkey-helpers.h:96:20: error: `PKEY_DISABLE_ACCESS' undeclared
     #define PKEY_MASK (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE)
                        ^
    protection_keys.c:218:45: error: `PKEY_DISABLE_WRITE' undeclared
     pkey_assert(flags & (PKEY_DISABLE_ACCESS | PKEY_DISABLE_WRITE));
                                                ^

Signed-off-by: Xingxing Su 
Signed-off-by: Andrew Morton 
Cc: Shuah Khan 
Cc: Sandipan Das 
Cc: John Hubbard 
Cc: Dave Hansen 
Cc: "Kirill A. Shutemov" 
Cc: Brian Geffon 
Cc: Mina Almasry 
Link: https://lkml.kernel.org/r/1606826876-30656-1-git-send-email-suxingxing@loongson.cn
Signed-off-by: Linus Torvalds

selftests/vm: 10x speedup for hmm-tests

2020-10-18T16:27:09+00:00

This patch reduces the running time for hmm-tests from about 10+ seconds,
to just under 1.0 second, for an approximately 10x speedup.  That brings
it in line with most of the other tests in selftests/vm, which mostly run
in < 1 sec.

This is done with a one-line change that simply reduces the number of
iterations of several tests, from 256, to 10.  Thanks to Ralph Campbell
for suggesting changing NTIMES as a way to get the speedup.

Suggested-by: Ralph Campbell 
Signed-off-by: John Hubbard 
Signed-off-by: Andrew Morton 
Cc: SeongJae Park 
Cc: Shuah Khan 
Link: https://lkml.kernel.org/r/20201003011721.44238-1-jhubbard@nvidia.com
Signed-off-by: Linus Torvalds

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

2020-10-15T22:11:56+00:00

Pull trivial updates from Jiri Kosina:
 "The latest advances in computer science from the trivial queue"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  xtensa: fix Kconfig typo
  spelling.txt: Remove some duplicate entries
  mtd: rawnand: oxnas: cleanup/simplify code
  selftests: vm: add fragment CONFIG_GUP_BENCHMARK
  perf: Fix opt help text for --no-bpf-event
  HID: logitech-dj: Fix spelling in comment
  bootconfig: Fix kernel message mentioning CONFIG_BOOT_CONFIG
  MAINTAINERS: rectify MMP SUPPORT after moving cputype.h
  scif: Fix spelling of EACCES
  printk: fix global comment
  lib/bitmap.c: fix spello
  fs: Fix missing 'bit' in comment

Merge tag 'linux-kselftest-fixes-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

2020-10-14T21:23:51+00:00

Pull kselftest updates from Shuah Khan:

 - a selftests harness fix to flush stdout before forking to avoid
   parent and child printing duplicates messages. This is evident when
   test output is redirected to a file.

 - a tools/ wide change to avoid comma separated statements from Joe
   Perches. This fix spans tools/lib, tools/power/cpupower, and
   selftests.

* tag 'linux-kselftest-fixes-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  tools: Avoid comma separated statements
  selftests/harness: Flush stdout before forking

selftests/vm: 8x compaction_test speedup

2020-10-14T01:38:34+00:00

This patch reduces the running time for compaction_test from about 27 sec,
to 3.3 sec, which is about an 8x speedup.

These numbers are for an Intel x86_64 system with 32 GB of DRAM.

The compaction_test.c program was spending most of its time doing mmap(),
1 MB at a time, on about 25 GB of memory.

Instead, do the mmaps 100 MB at a time.  (Going past 100 MB doesn't make
things go much faster, because other parts of the program are using the
remaining time.)

Signed-off-by: John Hubbard 
Signed-off-by: Andrew Morton 
Acked-by: Sri Jayaramappa 
Cc: Shuah Khan 
Cc: Mel Gorman 
Link: https://lkml.kernel.org/r/20201002080621.551044-2-jhubbard@nvidia.com
Signed-off-by: Linus Torvalds

tools/testing/selftests/vm/hmm-tests.c: use the new SKIP() macro

2020-10-14T01:38:32+00:00

Some tests might not be able to be run if resources like huge pages are
not available.  Mark these tests as skipped instead of simply passing.

Signed-off-by: Ralph Campbell 
Signed-off-by: Andrew Morton 
Reviewed-by: Jason Gunthorpe 
Cc: Jerome Glisse 
Cc: John Hubbard 
Cc: Shuah Khan 
Link: http://lkml.kernel.org/r/20200827190400.12608-1-rcampbell@nvidia.com
Signed-off-by: Linus Torvalds

selftests/vm: fix incorrect gcc invocation in some cases

2020-10-14T01:38:31+00:00

Avoid accidental wrong builds, due to built-in rules working just a little
bit too well--but not quite as well as required for our situation here.

In other words, "make userfaultfd" (for example) is supposed to fail to
build at all, because this Makefile only supports either "make" (all), or
"make /full/path".  However, the built-in rules, if not suppressed, will
pick up CFLAGS and the initial LDLIBS (but not the target-specific LDLIBS,
because those are only set for the full path target!).  This causes it to
get pretty far into building things despite using incorrect values such as
an *occasionally* incomplete LDLIBS value.

Signed-off-by: John Hubbard 
Signed-off-by: Andrew Morton 
Cc: Shuah Khan 
Cc: Jason Gunthorpe 
Link: https://lkml.kernel.org/r/20200915012901.1655280-3-jhubbard@nvidia.com
Signed-off-by: Linus Torvalds

selftests/vm: fix false build success on the second and later attempts

2020-10-14T01:38:31+00:00

Patch series "selftests/vm: fix some minor aggravating factors in the Makefile".

This fixes a couple of minor aggravating factors that I ran across while
trying to do some changes in selftests/vm.  These are simple things, but
like most things with GNU Make, it's rarely obvious what's wrong until you
understand *the entire Makefile and all of its includes*.

So while there is, of course, joy in learning those details, I thought I'd
fix these little things, so as to allow others to skip out on the Joy if
they so choose.  :)

First of all, if you have an item (let's choose userfaultfd for an
example) that fails to build, you might do this:

$ make -j32

    # ...you observe a failed item in the threaded output

# OK, let's get a closer look

$ make
    # ...but now the build quietly "succeeds".

That's what Patch 0001 fixes.

Second, if you instead attempt this approach for your closer look (a casual
mistake, as it's not supported):

$ make userfaultfd

    # ...userfaultfd fails to link, due to incomplete LDLIBS

That's what Patch 0002 fixes.

This patch (of 2):

If one or more of these selftest fail to build, then after the first
failure, subsequent invocations of "make" will make it appear that there
are no build failures, after all.

That's because the failed build products remain, with up-to-date
timestamps, thus tricking Make (and you!) into believing that there's
nothing else to build.

Fix this by telling Make to delete targets that didn't completely
succeed.

Signed-off-by: John Hubbard 
Signed-off-by: Andrew Morton 
Cc: Shuah Khan 
Cc: Jason Gunthorpe 
Link: https://lkml.kernel.org/r/20200915012901.1655280-1-jhubbard@nvidia.com
Link: https://lkml.kernel.org/r/20200915012901.1655280-2-jhubbard@nvidia.com
Signed-off-by: Linus Torvalds

mm/gup_benchmark: use pin_user_pages for FOLL_LONGTERM flag

2020-10-14T01:38:29+00:00

According to Documentation/core-api/pin_user_pages.rst, FOLL_PIN is a
prerequisite to FOLL_LONGTERM.  Another way of saying that is,
FOLL_LONGTERM is a specific case, more restrictive case of FOLL_PIN.

Almost all kernel modules are using pin_user_pages() with FOLL_LONGTERM,
mm/gup_benchmark.c seems to the only exception in which FOLL_PIN is not a
prerequisite to FOLL_LONGTERM.

Signed-off-by: Barry Song 
Signed-off-by: Andrew Morton 
Reviewed-by: John Hubbard 
Cc: Jan Kara 
Cc: Jérôme Glisse 
Cc: "Matthew Wilcox (Oracle)" 
Cc: Al Viro 
Cc: Christoph Hellwig 
Cc: Dan Williams 
Cc: Dave Chinner 
Cc: Jason Gunthorpe 
Cc: Jonathan Corbet 
Cc: Michal Hocko 
Cc: Mike Kravetz 
Cc: Shuah Khan 
Cc: Vlastimil Babka 
Link: http://lkml.kernel.org/r/20200815122056.29508-1-song.bao.hua@hisilicon.com
Signed-off-by: Linus Torvalds