Re: [PATCH 1/8] kasan,x86: Frob kasan_report() in an exception

[Peter Zijlstra]

On Wed, Mar 06, 2019 at 03:12:37PM +0100, Peter Zijlstra wrote:
> On Wed, Mar 06, 2019 at 03:01:33PM +0100, Dmitry Vyukov wrote:
> > On Wed, Mar 6, 2019 at 2:57 PM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> 
> > > I've not found callers of __asan_report_load* with AC=1 in the kernel
> > > yet. Under what condtions does GCC emit calls to these functions?
> > 
> > CONFIG_KASAN_INLINE=y
> > Then compiler inlines fast path into generated code and only calls
> > into runtime to report errors (also, faster, this should be a default
> > for anything other than tiny ROM controllers).
> 
> *sigh*, clearly I've not build enough kernels yet... Lemme go try that.

mm/kasan/generic_report.o: warning: objtool: __asan_report_load1_noabort()+0x0: call to __fentry__() with UACCESS enabled

You want to do:

CFLAGS_REMOVE_generic_report.o = -pg

like generic.o has?