From: Petr Mladek Date: Tue, 3 Jun 2014 16:23:21 +0000 (+0200) Subject: ftrace/x86: Call text_ip_addr() instead of the duplicated code X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=964f7b6b785651a75ef1cbad43a393ca52d4b4f7;p=linux-beck.git ftrace/x86: Call text_ip_addr() instead of the duplicated code I just went over this when looking at some Xen-related ftrace initialization problems. They were related to Xen code that is not upstream but this clean up would make sense here. I think that this was already the intention when text_ip_addr() was introduced in the commit 87fbb2ac6073a703930 (ftrace/x86: Use breakpoints for converting function graph caller). Anyway, better do it now before it shots people into their leg ;-) Link: http://lkml.kernel.org/p/1401812601-2359-1-git-send-email-pmladek@suse.cz Signed-off-by: Petr Mladek Signed-off-by: Steven Rostedt --- diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 89de3eaf8772..cbc4a91b131e 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -297,16 +297,7 @@ int ftrace_int3_handler(struct pt_regs *regs) static int ftrace_write(unsigned long ip, const char *val, int size) { - /* - * On x86_64, kernel text mappings are mapped read-only with - * CONFIG_DEBUG_RODATA. So we use the kernel identity mapping instead - * of the kernel text mapping to modify the kernel text. - * - * For 32bit kernels, these mappings are same and we can use - * kernel identity mapping to modify code. - */ - if (within(ip, (unsigned long)_text, (unsigned long)_etext)) - ip = (unsigned long)__va(__pa_symbol(ip)); + ip = text_ip_addr(ip); if (probe_kernel_write((void *)ip, val, size)) return -EPERM;