On Fri, May 05, 2017 at 11:17:05AM -0700, Ricardo Neri wrote:
We are not in a critical failure path. The invalid register type is caused when trying to decode invalid instruction bytes from a user-space program. Thus, simply print an error message. To prevent this warning from being abused from user space programs, use the rate-limited variant of printk.
Cc: Borislav Petkov bp@suse.de Cc: Andy Lutomirski luto@kernel.org Cc: Dave Hansen dave.hansen@linux.intel.com Cc: Adam Buchbinder adam.buchbinder@gmail.com Cc: Colin Ian King colin.king@canonical.com Cc: Lorenzo Stoakes lstoakes@gmail.com Cc: Qiaowei Ren qiaowei.ren@intel.com Cc: Arnaldo Carvalho de Melo acme@redhat.com Cc: Masami Hiramatsu mhiramat@kernel.org Cc: Adrian Hunter adrian.hunter@intel.com Cc: Kees Cook keescook@chromium.org Cc: Thomas Garnier thgarnie@google.com Cc: Peter Zijlstra peterz@infradead.org Cc: Dmitry Vyukov dvyukov@google.com Cc: Ravi V. Shankar ravi.v.shankar@intel.com Cc: x86@kernel.org Signed-off-by: Ricardo Neri ricardo.neri-calderon@linux.intel.com
arch/x86/lib/insn-eval.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index e746a6f..182e2ae 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -5,6 +5,7 @@ */ #include <linux/kernel.h> #include <linux/string.h> +#include <linux/ratelimit.h> #include <asm/inat.h> #include <asm/insn.h> #include <asm/insn-eval.h> @@ -85,9 +86,8 @@ static int get_reg_offset(struct insn *insn, struct pt_regs *regs, break;
default:
pr_err("invalid register type");BUG();break;
printk_ratelimited(KERN_ERR "insn-eval: x86: invalid register type");
You can use pr_err_ratelimited() and define "insn-eval" with pr_fmt. Look for examples in the tree.
Btw, "insn-eval" is perhaps not the right name - since we're building an instruction decoder, maybe it should be called "insn-dec" or so. I'm looking at those other arch/x86/lib/insn.c, arch/x86/include/asm/inat.h things and how they're starting to morph into one decoding facility, AFAICT.