From 17dcaca5dd46e37ca11d93ca3d68db35293e89d7 Mon Sep 17 00:00:00 2001 From: Alex Smith Date: Wed, 23 Jul 2014 14:40:06 +0100 Subject: [PATCH] MIPS: ptrace: Avoid smp_processor_id() when retrieving FPU IR commit 656ff9bef08c19a6471b49528dacb4cbbeb1e537 upstream. 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 Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7449/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman --- arch/mips/kernel/ptrace.c | 4 ++-- arch/mips/kernel/ptrace32.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c index 3d0879a32736..8bd13ed084d2 100644 --- a/arch/mips/kernel/ptrace.c +++ b/arch/mips/kernel/ptrace.c @@ -129,7 +129,7 @@ int ptrace_getfpregs(struct task_struct *child, __u32 __user *data) } __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; } @@ -611,7 +611,7 @@ long arch_ptrace(struct task_struct *child, long request, 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; diff --git a/arch/mips/kernel/ptrace32.c b/arch/mips/kernel/ptrace32.c index b40c3ca60ee5..a83fb730b387 100644 --- a/arch/mips/kernel/ptrace32.c +++ b/arch/mips/kernel/ptrace32.c @@ -129,7 +129,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request, 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;