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| author |   Andy Lutomirski <luto@kernel.org> | 2015-10-05 17:47:52 -0700 |
|---|---|---|
| committer |   Ingo Molnar <mingo@kernel.org> | 2015-10-07 11:34:07 +0200 |
| commit | 04235c00b6bb72b589e99efcc18883378ee76f1b (patch) | |
| tree | 814f6686f3983a319235928bc269209e121e6f6c /tools/testing/selftests/x86/raw_syscall_helper_32.S | |
| parent | selftests/x86: Add a test for vDSO unwinding (diff) | |
| download | linux-dev-04235c00b6bb72b589e99efcc18883378ee76f1b.tar.xz linux-dev-04235c00b6bb72b589e99efcc18883378ee76f1b.zip | |
selftests/x86: Add a test for ptrace syscall restart and arg modification
This tests assumptions about how fast syscall works wrt pt_regs
and, in particular, what happens if IP is decremented by 2
during a syscall.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1c44dbfe59000ba135bbf35ccc5d2433a0b31618.1444091584.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'tools/testing/selftests/x86/raw_syscall_helper_32.S')
| -rw-r--r-- | tools/testing/selftests/x86/raw_syscall_helper_32.S | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/tools/testing/selftests/x86/raw_syscall_helper_32.S b/tools/testing/selftests/x86/raw_syscall_helper_32.S new file mode 100644 index 000000000000..534e71e35c6a --- /dev/null +++ b/tools/testing/selftests/x86/raw_syscall_helper_32.S @@ -0,0 +1,46 @@ +.global sys32_helper +sys32_helper: + /* Args: syscall_args_32*, function pointer */ + pushl %ebp + pushl %ebx + pushl %esi + pushl %edi + movl 5*4(%esp), %eax /* pointer to args struct */ + + movl 1*4(%eax), %ebx + movl 2*4(%eax), %ecx + movl 3*4(%eax), %edx + movl 4*4(%eax), %esi + movl 5*4(%eax), %edi + movl 6*4(%eax), %ebp + movl 0*4(%eax), %eax + + call *(6*4)(%esp) /* Do the syscall */ + + /* Now we need to recover without losing any reg values */ + pushl %eax + movl 6*4(%esp), %eax + popl 0*4(%eax) + movl %ebx, 1*4(%eax) + movl %ecx, 2*4(%eax) + movl %edx, 3*4(%eax) + movl %esi, 4*4(%eax) + movl %edi, 5*4(%eax) + movl %ebp, 6*4(%eax) + + popl %edi + popl %esi + popl %ebx + popl %ebp + ret + + .type sys32_helper, @function + .size sys32_helper, .-sys32_helper + +.global int80_and_ret +int80_and_ret: + int $0x80 + ret + + .type int80_and_ret, @function + .size int80_and_ret, .-int80_and_ret |