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| author |   Dave Hansen <dave.hansen@linux.intel.com> | 2018-05-09 10:13:50 -0700 |
|---|---|---|
| committer |   Ingo Molnar <mingo@kernel.org> | 2018-05-14 11:14:45 +0200 |
| commit | f50b4878329ab61d8e05796f655adeb6f5fb57c6 (patch) | |
| tree | 60d88c468ac853a3982ab8221a19a363f69780d6 /tools/testing/selftests | |
| parent | x86/pkeys/selftests: Add PROT_EXEC test (diff) | |
| download | wireguard-linux-f50b4878329ab61d8e05796f655adeb6f5fb57c6.tar.xz wireguard-linux-f50b4878329ab61d8e05796f655adeb6f5fb57c6.zip | |
x86/pkeys/selftests: Fix pkey exhaustion test off-by-one
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 <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellermen <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180509171350.E1656B95@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'tools/testing/selftests')
| -rw-r--r-- | tools/testing/selftests/x86/protection_keys.c | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/tools/testing/selftests/x86/protection_keys.c b/tools/testing/selftests/x86/protection_keys.c index 8cb4fe58f381..55a4e349a45e 100644 --- a/tools/testing/selftests/x86/protection_keys.c +++ b/tools/testing/selftests/x86/protection_keys.c @@ -1163,12 +1163,15 @@ void test_pkey_alloc_exhaust(int *ptr, u16 pkey) pkey_assert(i < NR_PKEYS*2); /* - * There are 16 pkeys supported in hardware. One is taken - * up for the default (0) and another can be taken up by - * an execute-only mapping. Ensure that we can allocate - * at least 14 (16-2). + * There are 16 pkeys supported in hardware. Three are + * allocated by the time we get here: + * 1. The default key (0) + * 2. One possibly consumed by an execute-only mapping. + * 3. One allocated by the test code and passed in via + * 'pkey' to this function. + * Ensure that we can allocate at least another 13 (16-3). */ - pkey_assert(i >= NR_PKEYS-2); + pkey_assert(i >= NR_PKEYS-3); for (i = 0; i < nr_allocated_pkeys; i++) { err = sys_pkey_free(allocated_pkeys[i]); |