[PATCH v4] MIPS: adding a safety check for cpu_has_fpu

From: Stephen Zhang
Date: Sun May 01 2022 - 23:22:20 EST


From: Shida Zhang <zhangshida@xxxxxxxxxx>

There is a chance 'cpu_has_fpu' would still be overridden when the
CONFIG_MIPS_FP_SUPPORT configuration option has been disabled. So
add a safety check for 'cpu_has_fpu'.

Suggested-by: Maciej W. Rozycki <macro@xxxxxxxxxxx>
Signed-off-by: Shida Zhang <zhangshida@xxxxxxxxxx>
---
Changelog in v1 -> v2:
- Choose to redefine cpu_has_fpu to solve the problem silently.

Changelog in v2 -> v3:
- Choose to point out the error instead.

Changelog in v3 -> v4:
- Make the check work for 'nofpu' option.

arch/mips/include/asm/cpu-features.h | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/mips/include/asm/cpu-features.h b/arch/mips/include/asm/cpu-features.h
index de8cb2ccb781..c0983130a44c 100644
--- a/arch/mips/include/asm/cpu-features.h
+++ b/arch/mips/include/asm/cpu-features.h
@@ -133,6 +133,9 @@
# define raw_cpu_has_fpu 0
# endif
#else
+# if cpu_has_fpu
+# error "Forcing `cpu_has_fpu' to non-zero is not supported"
+# endif
# define raw_cpu_has_fpu cpu_has_fpu
#endif
#ifndef cpu_has_32fpr
--
2.30.2