From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-x242.google.com (mail-pf0-x242.google.com [IPv6:2607:f8b0:400e:c00::242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3y3tLK0q7NzDqh7 for ; Sat, 30 Sep 2017 12:54:17 +1000 (AEST) Received: by mail-pf0-x242.google.com with SMTP id a7so842999pfj.5 for ; Fri, 29 Sep 2017 19:54:17 -0700 (PDT) From: Sergey Senozhatsky To: Petr Mladek , Steven Rostedt Cc: Tony Luck , Fenghua Yu , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , James Bottomley , Helge Deller , Andrew Morton , Jessica Yu , Alexei Starovoitov , linux-ia64@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Sergey Senozhatsky Subject: [PATCHv3 3/7] ia64: Add .opd based function descriptor dereference Date: Sat, 30 Sep 2017 11:53:15 +0900 Message-Id: <20170930025319.987-4-sergey.senozhatsky@gmail.com> In-Reply-To: <20170930025319.987-1-sergey.senozhatsky@gmail.com> References: <20170930025319.987-1-sergey.senozhatsky@gmail.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , We are moving towards separate kernel and module function descriptor dereference callbacks. This patch enables it for IA64. For pointers that belong to the kernel - Added __start_opd and __end_opd pointers, to track the kernel .opd section address range; - Added dereference_kernel_function_descriptor(). Now we will dereference only function pointers that are within [__start_opd, __end_opd]; For pointers that belong to a module - Added dereference_module_function_descriptor() to handle module function descriptor dereference. Now we will dereference only pointers that are within [module->opd.start, module->opd.end]. Signed-off-by: Sergey Senozhatsky Tested-by: Helge Deller # parisc64 Tested-by: Santosh Sivaraj # powerpc64 Acked-by: Michael Ellerman # powerpc64 Tested-by: Tony Luck # ia64 --- arch/ia64/include/asm/sections.h | 10 +++++++++- arch/ia64/kernel/module.c | 13 +++++++++++++ arch/ia64/kernel/vmlinux.lds.S | 2 ++ 3 files changed, 24 insertions(+), 1 deletion(-) diff --git a/arch/ia64/include/asm/sections.h b/arch/ia64/include/asm/sections.h index de6bfa1ef8fb..3ba7ce9d8bc8 100644 --- a/arch/ia64/include/asm/sections.h +++ b/arch/ia64/include/asm/sections.h @@ -37,6 +37,14 @@ static inline unsigned long dereference_function_descriptor(unsigned long ptr) return ptr; } +#undef dereference_kernel_function_descriptor +static inline unsigned long +dereference_kernel_function_descriptor(unsigned long addr) +{ + if (addr < (unsigned long)__start_opd || + addr >= (unsigned long)__end_opd) + return addr; + return dereference_function_descriptor(addr); +} #endif /* _ASM_IA64_SECTIONS_H */ - diff --git a/arch/ia64/kernel/module.c b/arch/ia64/kernel/module.c index d1d945c6bd05..0741ae6fa957 100644 --- a/arch/ia64/kernel/module.c +++ b/arch/ia64/kernel/module.c @@ -35,6 +35,7 @@ #include #include +#include #define ARCH_MODULE_DEBUG 0 @@ -917,3 +918,15 @@ module_arch_cleanup (struct module *mod) if (mod->arch.core_unw_table) unw_remove_unwind_table(mod->arch.core_unw_table); } + +unsigned long +dereference_module_function_descriptor(struct module *mod, unsigned long addr) +{ + Elf64_Shdr *opd = mod->arch.opd; + + if (addr < opd->sh_addr || + addr >= (opd->sh_addr + opd->sh_size)) + return addr; + + return dereference_function_descriptor(addr); +} diff --git a/arch/ia64/kernel/vmlinux.lds.S b/arch/ia64/kernel/vmlinux.lds.S index 798026dde52e..f872ba5ff82a 100644 --- a/arch/ia64/kernel/vmlinux.lds.S +++ b/arch/ia64/kernel/vmlinux.lds.S @@ -107,7 +107,9 @@ SECTIONS { RODATA .opd : AT(ADDR(.opd) - LOAD_OFFSET) { + __start_opd = .; *(.opd) + __end_opd = .; } /* -- 2.14.2