linux/tools/testing/selftests/rseq, branch v5.14

rseq/selftests: Fix MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ build error under other arch.

2020-12-07T21:09:45Z

Except arch x86, the function rseq_offset_deref_addv is not defined. The function test_membarrier_manager_thread call rseq_offset_deref_addv produces a build error. The RSEQ_ARCH_HAS_OFFSET_DEREF_ADD should contain all the code for the MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ. If the other Arch implements this feature, defined RSEQ_ARCH_HAS_OFFSET_DEREF_ADD in the header file to ensure that this feature is available. Following build errors: param_test.c: In function ‘test_membarrier_worker_thread’: param_test.c:1164:10: warning: implicit declaration of function ‘rseq_offset_deref_addv’ ret = rseq_offset_deref_addv(&args->percpu_list_ptr, ^~~~~~~~~~~~~~~~~~~~~~ /tmp/ccMj9yHJ.o: In function `test_membarrier_worker_thread': param_test.c:1164: undefined reference to `rseq_offset_deref_addv' param_test.c:1164: undefined reference to `rseq_offset_deref_addv' collect2: error: ld returned 1 exit status make: *** [/selftests/rseq/param_test_benchmark] Error 1 Signed-off-by: Xingxing Su Acked-by: Mathieu Desnoyers Signed-off-by: Shuah Khan

rseq/selftests: Test MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ

2020-09-25T12:23:27Z

Based on Google-internal RSEQ work done by Paul Turner and Andrew Hunter. This patch adds a selftest for MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ. The test quite often fails without the previous patch in this patchset, but consistently passes with it. Signed-off-by: Peter Oskolkov Signed-off-by: Peter Zijlstra (Intel) Acked-by: Mathieu Desnoyers Link: https://lkml.kernel.org/r/20200923233618.2572849-3-posk@google.com

rseq/selftests,x86_64: Add rseq_offset_deref_addv()

2020-09-25T12:23:27Z

This patch adds rseq_offset_deref_addv() function to tools/testing/selftests/rseq/rseq-x86.h, to be used in a selftest in the next patch in the patchset. Once an architecture adds support for this function they should define "RSEQ_ARCH_HAS_OFFSET_DEREF_ADDV". Signed-off-by: Peter Oskolkov Signed-off-by: Peter Zijlstra (Intel) Acked-by: Mathieu Desnoyers Link: https://lkml.kernel.org/r/20200923233618.2572849-2-posk@google.com

.gitignore: add SPDX License Identifier

2020-03-25T10:50:48Z

Add SPDX License Identifier to all .gitignore files. Signed-off-by: Masahiro Yamada Signed-off-by: Greg Kroah-Hartman

selftests/rseq: Fix out-of-tree compilation

2020-02-20T15:57:12Z

Currently if you build with O=... the rseq tests don't build: $ make O=$PWD/output -C tools/testing/selftests/ TARGETS=rseq make: Entering directory '/linux/tools/testing/selftests' ... make[1]: Entering directory '/linux/tools/testing/selftests/rseq' gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L./ -Wl,-rpath=./ -shared -fPIC rseq.c -lpthread -o /linux/output/rseq/librseq.so gcc -O2 -Wall -g -I./ -I../../../../usr/include/ -L./ -Wl,-rpath=./ basic_test.c -lpthread -lrseq -o /linux/output/rseq/basic_test /usr/bin/ld: cannot find -lrseq collect2: error: ld returned 1 exit status This is because the library search path points to the source directory, not the output. We can fix it by changing the library search path to $(OUTPUT). Signed-off-by: Michael Ellerman Signed-off-by: Shuah Khan

selftests: Install settings files to fix TIMEOUT failures

2020-02-20T15:56:42Z

Commit 852c8cbf34d3 ("selftests/kselftest/runner.sh: Add 45 second timeout per test") added a 45 second timeout for tests, and also added a way for tests to customise the timeout via a settings file. For example the ftrace tests take multiple minutes to run, so they were given longer in commit b43e78f65b1d ("tracing/selftests: Turn off timeout setting"). This works when the tests are run from the source tree. However if the tests are installed with "make -C tools/testing/selftests install", the settings files are not copied into the install directory. When the tests are then run from the install directory the longer timeouts are not applied and the tests timeout incorrectly. So add the settings files to TEST_FILES of the appropriate Makefiles to cause the settings files to be installed using the existing install logic. Fixes: 852c8cbf34d3 ("selftests/kselftest/runner.sh: Add 45 second timeout per test") Signed-off-by: Michael Ellerman Signed-off-by: Shuah Khan

rseq/selftests: Clarify rseq_prepare_unload() helper requirements

2019-12-23T17:52:41Z

The rseq.h UAPI now documents that the rseq_cs field must be cleared before reclaiming memory that contains the targeted struct rseq_cs, but also that the rseq_cs field must be cleared before reclaiming memory of the code pointed to by the rseq_cs start_ip and post_commit_offset fields. While we can expect that use of dlclose(3) will typically unmap both struct rseq_cs and its associated code at once, nothing would theoretically prevent a JIT from reclaiming the code without reclaiming the struct rseq_cs, which would erroneously allow the kernel to consider new code which is not a rseq critical section as a rseq critical section following a code reclaim. Suggested-by: Florian Weimer Signed-off-by: Mathieu Desnoyers Cc: Shuah Khan Cc: Florian Weimer Cc: Thomas Gleixner Cc: Peter Zijlstra (Intel) Cc: "Paul E. McKenney" Cc: Boqun Feng Cc: "H . Peter Anvin" Cc: Paul Turner Cc: Dmitry Vyukov Signed-off-by: Shuah Khan

rseq/selftests: Fix: Namespace gettid() for compatibility with glibc 2.30

2019-12-23T17:52:41Z

glibc 2.30 introduces gettid() in public headers, which clashes with the internal static definition within rseq selftests. Rename gettid() to rseq_gettid() to eliminate this symbol name clash. Reported-by: Tommi T. Rantala Signed-off-by: Mathieu Desnoyers Cc: Shuah Khan Cc: Tommi T. Rantala Cc: Thomas Gleixner Cc: Peter Zijlstra (Intel) Cc: "Paul E. McKenney" Cc: Boqun Feng Cc: "H . Peter Anvin" Cc: Paul Turner Cc: Dmitry Vyukov Cc: # v4.18+ Signed-off-by: Shuah Khan

rseq/selftests: Turn off timeout setting

2019-12-23T17:52:41Z

As the rseq selftests can run for a long period of time, disable the timeout that the general selftests have. Signed-off-by: Mathieu Desnoyers Cc: Shuah Khan Cc: Thomas Gleixner Cc: Peter Zijlstra (Intel) Cc: "Paul E. McKenney" Cc: Boqun Feng Cc: "H . Peter Anvin" Cc: Paul Turner Cc: Dmitry Vyukov Signed-off-by: Shuah Khan

rseq/selftests: Fix Thumb mode build failure on arm32

2019-07-08T19:00:41Z

Using ".arm .inst" for the arm signature introduces build issues for programs compiled in Thumb mode because the assembler stays in the arm mode for the rest of the inline assembly. Revert to using a ".word" to express the signature as data instead. The choice of signature is a valid trap instruction on arm32 little endian, where both code and data are little endian. ARMv6+ big endian (BE8) generates mixed endianness code vs data: little-endian code and big-endian data. The data value of the signature needs to have its byte order reversed to generate the trap instruction. Prior to ARMv6, -mbig-endian generates big-endian code and data (which match), so the endianness of the data representation of the signature should not be reversed. However, the choice between BE32 and BE8 is done by the linker, so we cannot know whether code and data endianness will be mixed before the linker is invoked. So rather than try to play tricks with the linker, the rseq signature is simply data (not a trap instruction) prior to ARMv6 on big endian. This is why the signature is expressed as data (.word) rather than as instruction (.inst) in assembler. Because a ".word" is used to emit the signature, it will be interpreted as a literal pool by a disassembler, not as an actual instruction. Considering that the signature is not meant to be executed except in scenarios where the program execution is completely bogus, this should not be an issue. Signed-off-by: Mathieu Desnoyers Acked-by: Will Deacon CC: Peter Zijlstra CC: Thomas Gleixner CC: Joel Fernandes CC: Catalin Marinas CC: Dave Watson CC: Will Deacon CC: Shuah Khan CC: Andi Kleen CC: linux-kselftest@vger.kernel.org CC: "H . Peter Anvin" CC: Chris Lameter CC: Russell King CC: Michael Kerrisk CC: "Paul E . McKenney" CC: Paul Turner CC: Boqun Feng CC: Josh Triplett CC: Steven Rostedt CC: Ben Maurer CC: linux-api@vger.kernel.org CC: Andy Lutomirski CC: Andrew Morton CC: Linus Torvalds CC: Carlos O'Donell CC: Florian Weimer Signed-off-by: Shuah Khan