From: Alexander Duyck Date: Fri, 16 Nov 2012 21:57:32 +0000 (-0800) Subject: x86/ftrace: Use __pa_symbol instead of __pa on C visible symbols X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=217f155e9fc68bf2a6c58a7b47e0d1ce68d78818;p=linux-beck.git x86/ftrace: Use __pa_symbol instead of __pa on C visible symbols Instead of using __pa which is meant to be a general function for converting virtual addresses to physical addresses we can use __pa_symbol which is the preferred way of decoding kernel text virtual addresses to physical addresses. In this case we are not directly converting C visible symbols however if we know that the instruction pointer is somewhere between _text and _etext we know that we are going to be translating an address form the kernel text space. Cc: Steven Rostedt Cc: Frederic Weisbecker Signed-off-by: Alexander Duyck Link: http://lkml.kernel.org/r/20121116215718.8521.24026.stgit@ahduyck-cp1.jf.intel.com Signed-off-by: H. Peter Anvin --- diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 1d414029f1d8..42a392a9fd02 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -89,7 +89,7 @@ do_ftrace_mod_code(unsigned long ip, const void *new_code) * kernel identity mapping to modify code. */ if (within(ip, (unsigned long)_text, (unsigned long)_etext)) - ip = (unsigned long)__va(__pa(ip)); + ip = (unsigned long)__va(__pa_symbol(ip)); return probe_kernel_write((void *)ip, new_code, MCOUNT_INSN_SIZE); } @@ -279,7 +279,7 @@ static int ftrace_write(unsigned long ip, const char *val, int size) * kernel identity mapping to modify code. */ if (within(ip, (unsigned long)_text, (unsigned long)_etext)) - ip = (unsigned long)__va(__pa(ip)); + ip = (unsigned long)__va(__pa_symbol(ip)); return probe_kernel_write((void *)ip, val, size); }