linux.git/tools/testing/selftests/x86, branch v4.18

selftests/x86/sigreturn: Do minor cleanups

2018-06-27T07:36:56+00:00

We have short names for the requested and resulting register values.
Use them instead of spelling out the whole register entry for each
case.

Signed-off-by: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/bb3bc1f923a2f6fe7912d22a1068fe29d6033d38.1530076529.git.luto@kernel.org
Signed-off-by: Ingo Molnar

selftests/x86/sigreturn/64: Fix spurious failures on AMD CPUs

2018-06-27T07:36:56+00:00

When I wrote the sigreturn test, I didn't realize that AMD's busted
IRET behavior was different from Intel's busted IRET behavior:

On AMD CPUs, the CPU leaks the high 32 bits of the kernel stack pointer
to certain userspace contexts.  Gee, thanks.  There's very little
the kernel can do about it.  Modify the test so it passes.

Signed-off-by: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/86e7fd3564497f657de30a36da4505799eebef01.1530076529.git.luto@kernel.org
Signed-off-by: Ingo Molnar

selftests/x86: Detect -no-pie availability

2018-05-30T21:21:51+00:00

Some toolchains need -no-pie to build all tests, others do not support
the -no-pie flag at all.  Therefore, add another test for the
availability of the flag.

This amends commit 3346a6a4e5ba8c040360f753b26938cec31a4bdc
("selftests: x86: sysret_ss_attrs doesn't build on a PIE build").

Signed-off-by: Florian Weimer 
Acked-by: Randy Dunlap 
Tested-by: Randy Dunlap 
Signed-off-by: Shuah Khan (Samsung OSG)

x86/pkeys/selftests: Add a test for pkey 0

2018-05-14T09:14:45+00:00

Protection key 0 is the default key for all memory and will
not normally come back from pkey_alloc().  But, you might
still want pass it to mprotect_pkey().

This check ensures that you can use pkey 0.

Signed-off-by: Dave Hansen 
Cc: Andrew Morton 
Cc: Dave Hansen 
Cc: Linus Torvalds 
Cc: Michael Ellermen 
Cc: Peter Zijlstra 
Cc: Ram Pai 
Cc: Shuah Khan 
Cc: Thomas Gleixner 
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180509171356.9E40B254@viggo.jf.intel.com
Signed-off-by: Ingo Molnar

x86/pkeys/selftests: Save off 'prot' for allocations

2018-05-14T09:14:45+00:00

This makes it possible to to tell what 'prot' a given allocation
is supposed to have.  That way, if we want to change just the
pkey, we know what 'prot' to pass to mprotect_pkey().

Also, keep a record of the most recent allocation so the tests
can easily find it.

Signed-off-by: Dave Hansen 
Cc: Andrew Morton 
Cc: Dave Hansen 
Cc: Linus Torvalds 
Cc: Michael Ellermen 
Cc: Peter Zijlstra 
Cc: Ram Pai 
Cc: Shuah Khan 
Cc: Thomas Gleixner 
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180509171354.AA23E228@viggo.jf.intel.com
Signed-off-by: Ingo Molnar

x86/pkeys/selftests: Fix pointer math

2018-05-14T09:14:45+00:00

We dump out the entire area of the siginfo where the si_pkey_ptr is
supposed to be.  But, we do some math on the poitner, which is a u32.
We intended to do byte math, not u32 math on the pointer.

Cast it over to a u8* so it works.

Also, move this block of code to below th si_code check.  It doesn't
hurt anything, but the si_pkey field is gibberish for other signal
types.

Signed-off-by: Dave Hansen 
Cc: Andrew Morton 
Cc: Dave Hansen 
Cc: Linus Torvalds 
Cc: Michael Ellermen 
Cc: Peter Zijlstra 
Cc: Ram Pai 
Cc: Shuah Khan 
Cc: Thomas Gleixner 
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180509171352.9BE09819@viggo.jf.intel.com
Signed-off-by: Ingo Molnar

x86/pkeys/selftests: Fix pkey exhaustion test off-by-one

2018-05-14T09:14:45+00:00

In our "exhaust all pkeys" test, we make sure that there
is the expected number available.  Turns out that the
test did not cover the execute-only key, but discussed
it anyway.  It did *not* discuss the test-allocated
key.

Now that we have a test for the mprotect(PROT_EXEC) case,
this off-by-one issue showed itself.  Correct the off-by-
one and add the explanation for the case we missed.

Signed-off-by: Dave Hansen 
Cc: Andrew Morton 
Cc: Dave Hansen 
Cc: Linus Torvalds 
Cc: Michael Ellermen 
Cc: Peter Zijlstra 
Cc: Ram Pai 
Cc: Shuah Khan 
Cc: Thomas Gleixner 
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180509171350.E1656B95@viggo.jf.intel.com
Signed-off-by: Ingo Molnar

x86/pkeys/selftests: Add PROT_EXEC test

2018-05-14T09:14:45+00:00

Under the covers, implement executable-only memory with
protection keys when userspace calls mprotect(PROT_EXEC).

But, we did not have a selftest for that.  Now we do.

Signed-off-by: Dave Hansen 
Cc: Andrew Morton 
Cc: Dave Hansen 
Cc: Linus Torvalds 
Cc: Michael Ellermen 
Cc: Peter Zijlstra 
Cc: Ram Pai 
Cc: Shuah Khan 
Cc: Thomas Gleixner 
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180509171348.9EEE4BEF@viggo.jf.intel.com
Signed-off-by: Ingo Molnar

x86/pkeys/selftests: Factor out "instruction page"

2018-05-14T09:14:45+00:00

We currently have an execute-only test, but it is for
the explicit mprotect_pkey() interface.  We will soon
add a test for the implicit mprotect(PROT_EXEC)
enterface.  We need this code in both tests.

Signed-off-by: Dave Hansen 
Cc: Andrew Morton 
Cc: Dave Hansen 
Cc: Linus Torvalds 
Cc: Michael Ellermen 
Cc: Peter Zijlstra 
Cc: Ram Pai 
Cc: Shuah Khan 
Cc: Thomas Gleixner 
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180509171347.C64AB733@viggo.jf.intel.com
Signed-off-by: Ingo Molnar

x86/pkeys/selftests: Allow faults on unknown keys

2018-05-14T09:14:45+00:00

The exec-only pkey is allocated inside the kernel and userspace
is not told what it is.  So, allow PK faults to occur that have
an unknown key.

Signed-off-by: Dave Hansen 
Cc: Andrew Morton 
Cc: Dave Hansen 
Cc: Linus Torvalds 
Cc: Michael Ellermen 
Cc: Peter Zijlstra 
Cc: Ram Pai 
Cc: Shuah Khan 
Cc: Thomas Gleixner 
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180509171345.7FC7DA00@viggo.jf.intel.com
Signed-off-by: Ingo Molnar