MIPS: Set `si_code' for SIGFPE signals sent from emulation too

Rework `process_fpemu_return' and move IEEE 754 exception interpretation
there, from `do_fpe'.  Record the cause bits set in FCSR before they are
cleared and pass them through to `process_fpemu_return' so as to set
`si_code' correctly too for SIGFPE signals sent from emulation rather
than those issued by hardware with the FPE processor exception only.

For simplicity `mipsr2_decoder' assumes `*fcr31' has been preinitialised
and only sets it to anything if an FPU instruction has been emulated,
which in turn is the only case SIGFPE can be issued for here.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9705/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/include/asm/fpu_emulator.h b/arch/mips/include/asm/fpu_emulator.h
index 6370c82..bfcc5c6 100644 (file)
--- a/arch/mips/include/asm/fpu_emulator.h
+++ b/arch/mips/include/asm/fpu_emulator.h
@@ -66,7 +66,8 @@ extern int do_dsemulret(struct pt_regs *xcp);
 extern int fpu_emulator_cop1Handler(struct pt_regs *xcp,
                                    struct mips_fpu_struct *ctx, int has_fpu,
                                    void *__user *fault_addr);
-int process_fpemu_return(int sig, void __user *fault_addr);
+int process_fpemu_return(int sig, void __user *fault_addr,
+                        unsigned long fcr31);
 int mm_isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
                     unsigned long *contpc);
 

diff --cc arch/mips/include/asm/mips-r2-to-r6-emul.h
Simple merge

diff --cc arch/mips/kernel/mips-r2-to-r6-emul.c
Simple merge

diff --cc arch/mips/kernel/traps.c
Simple merge

diff --cc arch/mips/kernel/unaligned.c
Simple merge