On Mon, May 25, 2020 at 11:31:23AM +0800, YuanJunQing wrote: > Register "a1" is unsaved in this function, > when CONFIG_TRACE_IRQFLAGS is enabled, > the TRACE_IRQS_OFF macro will call trace_hardirqs_off(), > and this may change register "a1". > The variment of register "a1" may send SIGFPE signal > to task when call do_fpe(),and this may kill the task. > > Signed-off-by: YuanJunQing <yuanjunqin...@163.com> > --- > arch/mips/kernel/genex.S | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S > index 8236fb291e3f..956a76429773 100644 > --- a/arch/mips/kernel/genex.S > +++ b/arch/mips/kernel/genex.S > @@ -480,16 +480,18 @@ NESTED(nmi_handler, PT_SIZE, sp) > /* gas fails to assemble cfc1 for some archs (octeon).*/ \ > .set mips1 > SET_HARDFLOAT > - cfc1 a1, fcr31 > + cfc1 s0, fcr31 > .set pop > CLI > TRACE_IRQS_OFF > + move a1,s0 > .endm
do we realy need to read fcr31 that early ? Wouldn't it work to just move the cfc1 below TRACE_IRQS_OFF ? Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]
