MIPS: ptrace: Avoid smp_processor_id() when retrieving FPU IR
Whenever ptrace attempts to retrieve the FPU implementation register it
accesses it through current_cpu_data, which calls smp_processor_id().
Since the code may execute with preemption enabled, this can trigger
a warning. Fix this by using boot_cpu_data to get the IR instead.
Signed-off-by: Alex Smith <alex@alex-smith.me.uk>
Cc: <stable@vger.kernel.org> # v3.15+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7449/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c
index f639ccd..6063b11 100644
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -129,7 +129,7 @@
}
__put_user(child->thread.fpu.fcr31, data + 64);
- __put_user(current_cpu_data.fpu_id, data + 65);
+ __put_user(boot_cpu_data.fpu_id, data + 65);
return 0;
}
@@ -480,7 +480,7 @@
break;
case FPC_EIR:
/* implementation / version register */
- tmp = current_cpu_data.fpu_id;
+ tmp = boot_cpu_data.fpu_id;
break;
case DSP_BASE ... DSP_BASE + 5: {
dspreg_t *dregs;