syzkaller on risc-v

[Dmitry Vyukov]

On Wed, Jul 1, 2020 at 12:43 PM Björn Töpel <bjorn.topel at gmail.com> wrote:
> > > > On Jun 30 2020, Dmitry Vyukov wrote:
> > > >
> > > > > KASAN would be a prerequisite for testing risc-v on syzbot.
> > > >
> > > > You need to implement the GCC support first.
> > >
> > > Interesting. Björn claimed KASAN works already.  And there is:
> > >
> > > commit 8ad8b72721d0f07fa02dbe71f901743f9c71c8e6
> > > Author: Nick Hu
> > > Date:   Mon Jan 6 10:38:32 2020 -0800
> > >     riscv: Add KASAN support
> > >
> > > Is there any known issue with gcc?
> > > Did anyone try clang? AddressSanitizer pass in clang is
> > > arch-independent. Not sure about gcc... it looked mostly
> > > arch-independent.
> >
> > Weird. Did a quick bisect (just "does it boot with KASAN or not"
> > test), and this fell out:
> >
> > --
> > efca13989250c3edebaf8fcaa8ca7c966739c65a is the first bad commit
> > commit efca13989250c3edebaf8fcaa8ca7c966739c65a
> > Author: Atish Patra <atish.patra at wdc.com>
> > Date:   Tue Mar 17 18:11:37 2020 -0700
> >
> >     RISC-V: Introduce a new config for SBI v0.1
> >
> >     We now have SBI v0.2 which is more scalable and extendable to handle
> >     future needs for RISC-V supervisor interfaces.
> >
> >     Introduce a new config and move all SBI v0.1 code under that config.
> >     This allows to implement the new replacement SBI extensions cleanly
> >     and remove v0.1 extensions easily in future. Currently, the config
> >     is enabled by default. Once all M-mode software, with v0.1, is no
> >     longer in use, this config option and all relevant code can be easily
> >     removed.
> >
> >     Signed-off-by: Atish Patra <atish.patra at wdc.com>
> >     Reviewed-by: Anup Patel <anup at brainfault.org>
> >     Signed-off-by: Palmer Dabbelt <palmerdabbelt at google.com>
> >
> >  arch/riscv/Kconfig           |   7 +++
> >  arch/riscv/include/asm/sbi.h |   2 +
> >  arch/riscv/kernel/sbi.c      | 132 +++++++++++++++++++++++++++++++++++--------
> >  3 files changed, 118 insertions(+), 23 deletions(-)
> > --
> >
> > I'll dig a bit more.

We may need more KASAN_SANITIZE := n in some Makefiles.