diff options
author | Ralf Baechle <ralf@linux-mips.org> | 2005-05-09 09:16:07 -0400 |
---|---|---|
committer | Ralf Baechle <ralf@linux-mips.org> | 2005-10-29 14:31:13 -0400 |
commit | 1d74f6bc85cbdc4601e5aea1e67ccbd259f0c7f4 (patch) | |
tree | e9ffdef4000ab6e45a5d4c9233da0a7a67daf285 /arch/mips | |
parent | d547c5cc2186be9d74b0c595dc8059aef56cd445 (diff) |
__compute_return_epc() uses CFC1 instruction which might result in a
coprocessor unusable exception since the process can lose its fpu
context by preemption.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips')
-rw-r--r-- | arch/mips/kernel/branch.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/arch/mips/kernel/branch.c b/arch/mips/kernel/branch.c index 01117e977a7f..56aea5f526a7 100644 --- a/arch/mips/kernel/branch.c +++ b/arch/mips/kernel/branch.c | |||
@@ -12,6 +12,7 @@ | |||
12 | #include <asm/branch.h> | 12 | #include <asm/branch.h> |
13 | #include <asm/cpu.h> | 13 | #include <asm/cpu.h> |
14 | #include <asm/cpu-features.h> | 14 | #include <asm/cpu-features.h> |
15 | #include <asm/fpu.h> | ||
15 | #include <asm/inst.h> | 16 | #include <asm/inst.h> |
16 | #include <asm/ptrace.h> | 17 | #include <asm/ptrace.h> |
17 | #include <asm/uaccess.h> | 18 | #include <asm/uaccess.h> |
@@ -161,10 +162,13 @@ int __compute_return_epc(struct pt_regs *regs) | |||
161 | * And now the FPA/cp1 branch instructions. | 162 | * And now the FPA/cp1 branch instructions. |
162 | */ | 163 | */ |
163 | case cop1_op: | 164 | case cop1_op: |
164 | if (!cpu_has_fpu) | 165 | preempt_disable(); |
165 | fcr31 = current->thread.fpu.soft.fcr31; | 166 | if (is_fpu_owner()) |
166 | else | ||
167 | asm volatile("cfc1\t%0,$31" : "=r" (fcr31)); | 167 | asm volatile("cfc1\t%0,$31" : "=r" (fcr31)); |
168 | else | ||
169 | fcr31 = current->thread.fpu.hard.fcr31; | ||
170 | preempt_enable(); | ||
171 | |||
168 | bit = (insn.i_format.rt >> 2); | 172 | bit = (insn.i_format.rt >> 2); |
169 | bit += (bit != 0); | 173 | bit += (bit != 0); |
170 | bit += 23; | 174 | bit += 23; |