Commit 9cbf61a4 authored by Marcin Nowakowski's avatar Marcin Nowakowski Committed by Sasha Levin

MIPS: Avoid a BUG warning during prctl(PR_SET_FP_MODE, ...)

[ Upstream commit b244614a ]

cpu_has_fpu macro uses smp_processor_id() and is currently executed
with preemption enabled, that triggers the warning at runtime.

It is assumed throughout the kernel that if any CPU has an FPU, then all
CPUs would have an FPU as well, so it is safe to perform the check with
preemption enabled - change the code to use raw_ variant of the check to
avoid the warning.
Signed-off-by: default avatarMarcin Nowakowski <marcin.nowakowski@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org  # 4.0+
Patchwork: https://patchwork.linux-mips.org/patch/14125/Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
Signed-off-by: default avatarSasha Levin <alexander.levin@verizon.com>
parent fc6e4ced
......@@ -593,14 +593,14 @@ int mips_set_process_fp_mode(struct task_struct *task, unsigned int value)
return -EOPNOTSUPP;
/* Avoid inadvertently triggering emulation */
if ((value & PR_FP_MODE_FR) && cpu_has_fpu &&
!(current_cpu_data.fpu_id & MIPS_FPIR_F64))
if ((value & PR_FP_MODE_FR) && raw_cpu_has_fpu &&
!(raw_current_cpu_data.fpu_id & MIPS_FPIR_F64))
return -EOPNOTSUPP;
if ((value & PR_FP_MODE_FRE) && cpu_has_fpu && !cpu_has_fre)
if ((value & PR_FP_MODE_FRE) && raw_cpu_has_fpu && !cpu_has_fre)
return -EOPNOTSUPP;
/* FR = 0 not supported in MIPS R6 */
if (!(value & PR_FP_MODE_FR) && cpu_has_fpu && cpu_has_mips_r6)
if (!(value & PR_FP_MODE_FR) && raw_cpu_has_fpu && cpu_has_mips_r6)
return -EOPNOTSUPP;
/* Proceed with the mode switch */
......
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