Messages in this thread | | | Subject | Re: [PATCH] ftrace: recordmcount: avoid STT_FUNC symbols as base on ARM | From | Steven Rostedt <> | Date | Tue, 17 May 2011 20:27:15 -0400 |
| |
On Tue, 2011-05-17 at 23:50 +0100, Russell King - ARM Linux wrote: > On Tue, May 17, 2011 at 12:10:29PM -0400, Steven Rostedt wrote: > > On Wed, 2011-05-11 at 22:53 +0530, Rabin Vincent wrote: > > > While find_secsym_ndx often finds the unamed local STT_SECTION, if a > > > section has only one function in it, the ARM toolchain generates the > > > STT_FUNC symbol before the STT_SECTION, and recordmcount finds this > > > instead. > > > > > > This is problematic on ARM because in ARM ELFs, "if a [STT_FUNC] symbol > > > addresses a Thumb instruction, its value is the address of the > > > instruction with bit zero set (in a relocatable object, the section > > > offset with bit zero set)". This leads to incorrect mcount addresses > > > being recorded. > > > > > > Fix this by not using STT_FUNC symbols as the base on ARM. > > > > Hi Russell, > > > > Can you give me an Acked-by on this patch? > > It would be better for someone who knows the ELF format for ARM and > its weirdnesses to ack this patch. I'm afraid my ARM ELF format > knowledge was been superseded when EABI came along and introduced > all sorts of new stuff.
OK, in that case, I'll just apply the patch.
Thanks!
-- Steve
| |