MIPS: Ensure Config5.UFE is clear on boot

As is done for UFR, ensure that userland cannot directly manipulate the
mode by clearing the UFE bit during boot.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/7677/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index d76f189291bc67b6ccb4c89b51dc740102d9415b..d68ad96392f8dec168614ada539724d27829ad74 100644 (file)
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -461,7 +461,7 @@ static inline unsigned int decode_config5(struct cpuinfo_mips *c)
        unsigned int config5;
 
        config5 = read_c0_config5();
-       config5 &= ~MIPS_CONF5_UFR;
+       config5 &= ~(MIPS_CONF5_UFR | MIPS_CONF5_UFE);
        write_c0_config5(config5);
 
        if (config5 & MIPS_CONF5_EVA)