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>

1 files changed, 2 insertions, 2 deletions

diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c
index bbb69695a0a1..cf51ad36f213 100644
--- a/arch/mips/kernel/unaligned.c
+++ b/arch/mips/kernel/unaligned.c
@@ -1076,7 +1076,7 @@ static void emulate_load_store_insn(struct pt_regs *regs,
                 own_fpu(1);     /* Restore FPU state. */
 
                 /* Signal if something went wrong. */
-                process_fpemu_return(res, fault_addr);
+                process_fpemu_return(res, fault_addr, 0);
 
                 if (res == 0)
                         break;
@@ -1511,7 +1511,7 @@ fpu_emul:
                 own_fpu(1);     /* restore FPU state */
 
                 /* If something went wrong, signal */
-                process_fpemu_return(res, fault_addr);
+                process_fpemu_return(res, fault_addr, 0);
 
                 if (res == 0)
                         goto success;