Re: [PATCH v3 1/1] livepatch: add support on s390

[Josh Poimboeuf <jpoimboe@redhat.com>]

On Tue, Mar 24, 2015 at 05:51:00PM +0100, Jiri Slaby wrote:
> This is a trivial port from kGraft. Module relocations are not
> supported.
> 
> [v2] return ENOSYS
> 
> Signed-off-by: Jiri Slaby <jslaby@suse.cz>
> ---
>  arch/s390/Kconfig                 |  3 +++
>  arch/s390/include/asm/livepatch.h | 43 +++++++++++++++++++++++++++++++++++++++
>  2 files changed, 46 insertions(+)
>  create mode 100644 arch/s390/include/asm/livepatch.h
> 
> diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
> index 5f01f22b4f16..de2726a487b0 100644
> --- a/arch/s390/Kconfig
> +++ b/arch/s390/Kconfig
> @@ -134,6 +134,7 @@ config S390
>  	select HAVE_KPROBES
>  	select HAVE_KRETPROBES
>  	select HAVE_KVM
> +	select HAVE_LIVEPATCH
>  	select HAVE_MEMBLOCK
>  	select HAVE_MEMBLOCK_NODE_MAP
>  	select HAVE_MEMBLOCK_PHYS_MAP
> @@ -164,6 +165,8 @@ source "init/Kconfig"
>  
>  source "kernel/Kconfig.freezer"
>  
> +source "kernel/livepatch/Kconfig"
> +
>  menu "Processor type and features"
>  
>  config HAVE_MARCH_Z900_FEATURES
> diff --git a/arch/s390/include/asm/livepatch.h b/arch/s390/include/asm/livepatch.h
> new file mode 100644
> index 000000000000..dc2f6e909e04
> --- /dev/null
> +++ b/arch/s390/include/asm/livepatch.h
> @@ -0,0 +1,43 @@
> +/*
> + * livepatch.h - s390-specific Kernel Live Patching Core
> + *
> + *  Copyright (c) 2013-2015 SUSE
> + *   Authors: Jiri Kosina
> + *	      Vojtech Pavlik
> + *	      Jiri Slaby
> + */
> +
> +/*
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the Free
> + * Software Foundation; either version 2 of the License, or (at your option)
> + * any later version.
> + */
> +
> +#ifndef ASM_LIVEPATCH_H
> +#define ASM_LIVEPATCH_H
> +
> +#include <linux/module.h>
> +
> +#ifdef CONFIG_LIVEPATCH
> +static inline int klp_check_compiler_support(void)
> +{
> +	return 1;
> +}

This should actually return 0 on success.

> +
> +static inline int klp_write_module_reloc(struct module *mod, unsigned long
> +		type, unsigned long loc, unsigned long value)
> +{
> +	/* not supported yet */
> +	return -ENOSYS;
> +}
> +
> +static inline void klp_arch_set_pc(struct pt_regs *regs, unsigned long ip)
> +{
> +	regs->psw.addr = ip;
> +}
> +#else
> +#error Live patching support is disabled; check CONFIG_LIVEPATCH
> +#endif
> +
> +#endif
> -- 
> 2.3.3
> 

-- 
Josh