On Mon, Oct 07, 2024 at 08:47:43PM -0400, Steven Rostedt wrote: > From: Steven Rostedt <rostedt@xxxxxxxxxxx> > > ftrace_regs was created to hold registers that store information to save > function parameters, return value and stack. Since it is a subset of > pt_regs, it should only be used by its accessor functions. But because > pt_regs can easily be taken from ftrace_regs (on most archs), it is > tempting to use it directly. But when running on other architectures, it > may fail to build or worse, build but crash the kernel! > > Instead, make struct ftrace_regs an empty structure and have the > architectures define __arch_ftrace_regs and all the accessor functions > will typecast to it to get to the actual fields. This will help avoid > usage of ftrace_regs directly. > > Link: https://lore.kernel.org/all/20241007171027.629bdafd@xxxxxxxxxxxxxxxxxx/ > > Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> > --- > Note, I tried to cros-compile the affected architectures, > but my builds failed for 32 bit powerpc and s390 (without this patch). > It mostly compiled, and the affected files seemed to build. > > arch/arm64/include/asm/ftrace.h | 20 +++++++++-------- > arch/arm64/kernel/asm-offsets.c | 22 +++++++++---------- > arch/arm64/kernel/ftrace.c | 10 ++++----- For arm64: Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>
