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    SubjectRe: [PATCH V4 4/8] riscv: traps: Add noinstr to prevent instrumentation inserted
    On Sat, Sep 10, 2022 at 05:17:44PM +0800, Guo Ren wrote:

    > > > -asmlinkage __visible __trap_section void name(struct pt_regs *regs) \
    > > > +asmlinkage __visible __trap_section void noinstr name(struct pt_regs *regs) \
    > >
    > > But now you have __trap_section and noinstr both adding a section
    > > attribute.
    >
    > Oops, thx for correcting. Here is my solution.
    >
    > diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
    > index 635e6ec26938..eba744caa711 100644
    > --- a/arch/riscv/kernel/traps.c
    > +++ b/arch/riscv/kernel/traps.c
    > @@ -92,9 +92,11 @@ static void do_trap_error(struct pt_regs *regs, int
    > signo, int code,
    > }
    >
    > #if defined(CONFIG_XIP_KERNEL) && defined(CONFIG_RISCV_ALTERNATIVE)
    > -#define __trap_section __section(".xip.traps")
    > +#define __trap_section \
    > + noinline notrace __attribute((__section__(".xip.traps"))) \
    > + __no_kcsan __no_sanitize_address __no_profile __no_sanitize_coverage
    > #else
    > -#define __trap_section
    > +#define __trap_section noinstr
    > #endif

    This is almost guaranteed to get out of sync when the compiler guys add
    yet another sanitizier. Please consider picking up this patch:

    https://lore.kernel.org/all/20211110115736.3776-7-jiangshanlai@gmail.com/

    and using __noinstr_section(".xip.traps")

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