kernel/linux.git/tools/testing/selftests/x86, branch v4.19.237

selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random

2021-07-20T14:15:58+00:00

[ Upstream commit f36ef407628835a7d7fb3d235b1f1aac7022d9a3 ] Patch series "selftests/vm/pkeys: Bug fixes and a new test". There has been a lot of activity on the x86 front around the XSAVE architecture which is used to context-switch processor state (among other things). In addition, AMD has recently joined the protection keys club by adding processor support for PKU. The AMD implementation helped uncover a kernel bug around the PKRU "init state", which actually applied to Intel's implementation but was just harder to hit. This series adds a test which is expected to help find this class of bug both on AMD and Intel. All the work around pkeys on x86 also uncovered a few bugs in the selftest. This patch (of 4): The "random" pkey allocation code currently does the good old: srand((unsigned int)time(NULL)); *But*, it unfortunately does this on every random pkey allocation. There may be thousands of these a second. time() has a one second resolution. So, each time alloc_random_pkey() is called, the PRNG is *RESET* to time(). This is nasty. Normally, if you do: srand(); foo = rand(); bar = rand(); You'll be quite guaranteed that 'foo' and 'bar' are different. But, if you do: srand(1); foo = rand(); srand(1); bar = rand(); You are quite guaranteed that 'foo' and 'bar' are the *SAME*. The recent "fix" effectively forced the test case to use the same "random" pkey for the whole test, unless the test run crossed a second boundary. Only run srand() once at program startup. This explains some very odd and persistent test failures I've been seeing. Link: https://lkml.kernel.org/r/20210611164153.91B76FB8@viggo.jf.intel.com Link: https://lkml.kernel.org/r/20210611164155.192D00FF@viggo.jf.intel.com Fixes: 6e373263ce07 ("selftests/vm/pkeys: fix alloc_random_pkey() to make it really random") Signed-off-by: Dave Hansen Signed-off-by: Thomas Gleixner Tested-by: Aneesh Kumar K.V Cc: Ram Pai Cc: Sandipan Das Cc: Florian Weimer Cc: "Desnes A. Nunes do Rosario" Cc: Ingo Molnar Cc: Thiago Jung Bauermann Cc: Michael Ellerman Cc: Michal Hocko Cc: Michal Suchanek Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

selftests/x86/syscall_nt: Clear weird flags after each test

2020-10-01T11:14:49+00:00

[ Upstream commit a61fa2799ef9bf6c4f54cf7295036577cececc72 ] Clear the weird flags before logging to improve strace output -- logging results while, say, TF is set does no one any favors. Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/907bfa5a42d4475b8245e18b67a04b13ca51ffdb.1593191971.git.luto@kernel.org Signed-off-by: Sasha Levin

selftests/vm/pkeys: fix alloc_random_pkey() to make it really random

2020-06-25T13:33:02+00:00

[ Upstream commit 6e373263ce07eeaa6410843179535fbdf561fc31 ] alloc_random_pkey() was allocating the same pkey every time. Not all pkeys were geting tested. This fixes it. Signed-off-by: Ram Pai Signed-off-by: Sandipan Das Signed-off-by: Andrew Morton Acked-by: Dave Hansen Cc: Dave Hansen Cc: Florian Weimer Cc: "Desnes A. Nunes do Rosario" Cc: Ingo Molnar Cc: Thiago Jung Bauermann Cc: "Aneesh Kumar K.V" Cc: Michael Ellerman Cc: Michal Hocko Cc: Michal Suchanek Cc: Shuah Khan Link: http://lkml.kernel.org/r/0162f55816d4e783a0d6e49e554d0ab9a3c9a23b.1585646528.git.sandipan@linux.ibm.com Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

selftests/x86/ptrace_syscall_32: Fix no-vDSO segfault

2020-04-17T08:48:40+00:00

[ Upstream commit 630b99ab60aa972052a4202a1ff96c7e45eb0054 ] If AT_SYSINFO is not present, don't try to call a NULL pointer. Reported-by: kbuild test robot Signed-off-by: Andy Lutomirski Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/faaf688265a7e1a5b944d6f8bc0f6368158306d3.1584052409.git.luto@kernel.org Signed-off-by: Sasha Levin

x86/selftests/pkeys: Fork() to check for state being preserved

2019-01-31T07:14:39+00:00

commit e1812933b17be7814f51b6c310c5d1ced7a9a5f5 upstream. There was a bug where the per-mm pkey state was not being preserved across fork() in the child. fork() is performed in the pkey selftests, but all of the pkey activity is performed in the parent. The child does not perform any actions sensitive to pkey state. To make the test more sensitive to these kinds of bugs, add a fork() where the parent exits, and execution continues in the child. To achieve this let the key exhaustion test not terminate at the first allocation failure and fork after 2*NR_PKEYS loops and continue in the child. Signed-off-by: Dave Hansen Signed-off-by: Thomas Gleixner Cc: bp@alien8.de Cc: hpa@zytor.com Cc: peterz@infradead.org Cc: mpe@ellerman.id.au Cc: will.deacon@arm.com Cc: luto@kernel.org Cc: jroedel@suse.de Cc: stable@vger.kernel.org Cc: Borislav Petkov Cc: "H. Peter Anvin" Cc: Peter Zijlstra Cc: Michael Ellerman Cc: Will Deacon Cc: Andy Lutomirski Cc: Joerg Roedel Link: https://lkml.kernel.org/r/20190102215657.585704B7@viggo.jf.intel.com Signed-off-by: Greg Kroah-Hartman

x86/vdso: Fix vDSO syscall fallback asm constraint regression

2018-10-04T06:17:50+00:00

When I added the missing memory outputs, I failed to update the index of the first argument (ebx) on 32-bit builds, which broke the fallbacks. Somehow I must have screwed up my testing or gotten lucky. Add another test to cover gettimeofday() as well. Signed-off-by: Andy Lutomirski Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: stable@vger.kernel.org Fixes: 715bd9d12f84 ("x86/vdso: Fix asm constraints on vDSO syscall fallbacks") Link: http://lkml.kernel.org/r/21bd45ab04b6d838278fa5bebfa9163eceffa13c.1538608971.git.luto@kernel.org Signed-off-by: Ingo Molnar

selftests/x86: Add clock_gettime() tests to test_vdso

2018-10-02T06:28:32+00:00

Now that the vDSO implementation of clock_gettime() is getting reworked, add a selftest for it. This tests that its output is consistent with the syscall version. This is marked for stable to serve as a test for commit 715bd9d12f84 ("x86/vdso: Fix asm constraints on vDSO syscall fallbacks") Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/082399674de2619b2befd8c0dde49b260605b126.1538422295.git.luto@kernel.org

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)