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>
>= +static void notify=5Fprocess(pid=5Ft pid, u64 fault=5Faddr)
> +{> + int rc;
> + struct kernel=5Fsiginfo info;
> +
> += memset(&info, 0, sizeof(info));
> +
> + info.si=5Fsigno = =3D SIGSEGV;
> + info.si=5Ferrno =3D EFAULT;
> + info.si=5Fcode= =3D SEGV=5FMAPERR;
> +
> + info.si=5Faddr =3D (void *)fault=5F= addr;
> + rcu=5Fread=5Flock();
> + rc =3D kill=5Fpid=5Finfo(SIG= SEGV, &info, find=5Fvpid(pid));
> + rcu=5Fread=5Funlock();
>= ; +
> + pr=5Fdevel("%s(): pid %d kill=5Fproc=5Finfo() rc %d\n", =5F= =5Ffunc=5F=5F, pid, rc);
> +}

Shouldn't this use force=5Fsig= =5Ffault=5Fto=5Ftask instead?

User space send compression request as Coprocessor Reques= t Block (CRB) with CSB (status block)to NX directly and polls on CSB a= ddress. NX updates CSB after processing the request. If NX sees f= ault on the request buffer or CSB, interrupts kernel. So generally CSB= should be valid since it supposed to poll csb.flags.

If an application does not behave as expected or NX = pastes wrong information, an error message will be printed and send signal = to an application. So applications or libnxz can ignore SEGV signal or= can have their own handlers.