kernel/linux.git/tools/testing/selftests/x86, branch v4.17.1

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

x86/pkeys/selftests: Avoid printf-in-signal deadlocks

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

printf() and friends are unusable in signal handlers. They deadlock. The pkey selftest does not do any normal printing in signal handlers, only extra debugging. So, just print the format string so we get *some* output when debugging. 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/20180509171344.C53FD2F3@viggo.jf.intel.com Signed-off-by: Ingo Molnar

x86/pkeys/selftests: Remove dead debugging code, fix dprint_in_signal

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

There is some noisy debug code at the end of the signal handler. It was disabled by an early, unconditional "return". However, that return also hid a dprint_in_signal=0, which kept dprint_in_signal=1 and effectively locked us into permanent dprint_in_signal=1 behavior. Remove the return and the dead code, fixing dprint_in_signal. 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/20180509171342.846B9B2E@viggo.jf.intel.com Signed-off-by: Ingo Molnar

x86/pkeys/selftests: Stop using assert()

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

If we use assert(), the program "crashes". That can be scary to users, so stop doing it. Just exit with a >0 exit code instead. 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/20180509171340.E63EF7DA@viggo.jf.intel.com Signed-off-by: Ingo Molnar