syzkaller on risc-v

[Björn Töpel]

On Wed, 1 Jul 2020 at 12:42, Björn Töpel <bjorn.topel at gmail.com> wrote:
>
> On Tue, 30 Jun 2020 at 15:27, Dmitry Vyukov <dvyukov at google.com> wrote:
> >
> > On Tue, Jun 30, 2020 at 3:14 PM Andreas Schwab <schwab at suse.de> 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.
>

Oh, forgot one thing; I'm booting the kernel with OpenSBI (OpenSBI
v0.8-3-gec3e5b14d52a) and not the Berkley loader.