
This refactors do_unexpected_base() to clean up some code. It also fixes the following bugs in test_ptrace_write_gsbase(): - Incorrect printf() format string caused crashes. - Hardcoded 0x7 for the gs selector was not reliably correct. It also documents the fact that the test is expected to fail on old kernels. Fixes:a87730cc3a
("selftests/x86/fsgsbase: Test ptracer-induced GSBASE write with FSGSBASE") Fixes:1b6858d5a2
("selftests/x86/fsgsbase: Test ptracer-induced GSBASE write") Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: "BaeChang Seok" <chang.seok.bae@intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: "H . Peter Anvin" <hpa@zytor.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: "BaeChang Seok" <chang.seok.bae@intel.com> Link: https://lkml.kernel.org/r/bab29c84f2475e2c30ddb00f1b877fcd7f4f96a8.1562125333.git.luto@kernel.org