I think there is a bug in the _save_fp_context function in
arch/mips/kernel/r4k_fpu.S
The problem is the following piece of code:
jr ra
.set nomacro
EX(sw t0,SC_FPC_EIR(a0))
nop
.set macro
First of all what should the ".set nomacro" do?
If it means that the EX macro shouldn't be used then this entry wouldn't
get into __ex_table, which would be wrong.
But it look like it uses the macro anyway, regardless of the ".set
nomacro", at least with the compiler I use.
Never the less we do not handle entries in the __ex_table which is
located in a branch delay.
So we need to handle the situation where we take a page fault on an
instruction which is located in a brach delay slot, or we don't put the
"potential" faulting instruction in a delay slot.
Any ideas, how we should handle this in a nice and clean way?
/Carsten
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