um: add extended processor state save/restore support

This patch extends save_fp_registers() and restore_fp_registers() to use
PTRACE_GETREGSET and PTRACE_SETREGSET with the XSTATE note type, adding
support for new processor state extensions between context switches.

When the new ptrace requests are unavailable, it falls back to the old
PTRACE_GETFPREGS and PTRACE_SETFPREGS methods, which have been renamed to
save_i387_registers() and restore_i387_registers().

Now these functions expect *fp_regs to have the space of an _xstate struct.
Thus, this also makes ptrace in UML responde to PTRACE_GETFPREGS/_SETFPREG
requests with a user_i387_struct (thus independent from HOST_FP_SIZE), and
by calling save_i387_registers() and restore_i387_registers() instead of
the extended save_fp_registers() and restore_fp_registers() functions.

Signed-off-by: Eli Cooper <elicooper@gmx.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 48af59aae129..d55a473dca4a 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -402,6 +402,6 @@ int elf_core_copy_fpregs(struct task_struct *t, elf_fpregset_t *fpu)
 {
 	int cpu = current_thread_info()->cpu;
 
-	return save_fp_registers(userspace_pid[cpu], (unsigned long *) fpu);
+	return save_i387_registers(userspace_pid[cpu], (unsigned long *) fpu);
 }