On Tue, Sep 19, 2017 at 2:46 PM, Andrey Ryabinin <aryabi...@virtuozzo.com> wrote: > There is no need to surround kaslr_offset() with CONFIG_RANDOMIZE_BASE ifdef. > kaslr_offset() will just return 0 if CONFIG_RANDOMIZE_BASE isn't set. > > Signed-off-by: Andrey Ryabinin <aryabi...@virtuozzo.com>
As you said this is a very hot function, but this changes code from: 2e: 48 8b 75 08 mov 0x8(%rbp),%rsi to: 2b: 48 c7 c2 00 00 00 81 mov $0xffffffff81000000,%rdx 32: 48 81 ea 00 00 00 00 sub $0x0,%rdx 3c: 48 03 55 08 add 0x8(%rbp),%rdx This also changes semantics, as returned PCs won't match nm/objdump output. > --- > kernel/kcov.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/kernel/kcov.c b/kernel/kcov.c > index 3f693a0f6f3e..2f0e7a7c7afc 100644 > --- a/kernel/kcov.c > +++ b/kernel/kcov.c > @@ -69,9 +69,7 @@ void notrace __sanitizer_cov_trace_pc(void) > unsigned long pos; > unsigned long ip = _RET_IP_; > > -#ifdef CONFIG_RANDOMIZE_BASE > ip -= kaslr_offset(); > -#endif > > /* > * There is some code that runs in interrupts but for which > -- > 2.13.5 >
