On Thu, Mar 5, 2020 at 6:37 AM Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> wrote:
>
> Hi all,
>
> After merging the akpm-current tree, today's linux-next build (x86_64
> allmodconfig) produced this warning:
>
> mm/kasan/common.o: warning: objtool: kasan_report()+0x17: call to report_enabled() with UACCESS enabled
> In file included from include/linux/bitmap.h:9,
> from include/linux/cpumask.h:12,
> from arch/x86/include/asm/paravirt.h:17,
> from arch/x86/include/asm/irqflags.h:72,
> from include/linux/irqflags.h:16,
> from include/linux/rcupdate.h:26,
> from include/linux/rculist.h:11,
> from include/linux/pid.h:5,
> from include/linux/sched.h:14,
> from include/linux/uaccess.h:6,
> from arch/x86/include/asm/fpu/xstate.h:5,
> from arch/x86/include/asm/pgtable.h:26,
> from include/linux/kasan.h:15,
> from lib/test_kasan.c:12:
> In function 'memmove',
> inlined from 'kmalloc_memmove_invalid_size' at lib/test_kasan.c:301:2:
> include/linux/string.h:441:9: warning: '__builtin_memmove' specified bound 18446744073709551614 exceeds maximum object size 9223372036854775807 [-Wstringop-overflow=]
+kasan-dev
We probably need to make this 18446744073709551614 constant "dynamic"
so that compiler does not see it.
Walter, will you take a look? Thanks
> 441 | return __builtin_memmove(p, q, size);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> Introduced by commit
>
> 519e500fac64 ("kasan: add test for invalid size in memmove")
>
> That's a bit annoying during a normal x86_64 allmodconfig build ...
>
> --
> Cheers,
> Stephen Rothwell
