[PATCH 4.4 10/18] MIPS: IRQ Stack: Fix erroneous jal to plat_irq_dispatch

Greg Kroah-Hartman
2017-04-16T08:03:29Z

From: Matt Redfearn <matt.redfearn@imgtec.com>

commit c25f8064c1d5731a2ce5664def890140dcdd3e5c upstream.

Commit dda45f701c9d ("MIPS: Switch to the irq_stack in interrupts")
changed both the normal and vectored interrupt handlers. Unfortunately
the vectored version, "except_vec_vi_handler", was incorrectly modified
to unconditionally jal to plat_irq_dispatch, rather than doing a jalr to
the vectored handler that has been set up. This is ok for many platforms
which set the vectored handler to plat_irq_dispatch anyway, but will
cause problems with platforms that use other handlers.

Fixes: dda45f701c9d ("MIPS: Switch to the irq_stack in interrupts")
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/15110/
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/mips/kernel/genex.S | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/mips/kernel/genex.S
+++ b/arch/mips/kernel/genex.S
@@ -330,7 +330,7 @@ NESTED(except_vec_vi_handler, 0, sp)
PTR_ADD sp, t0, t1

2:
- jal plat_irq_dispatch
+ jalr v0

/* Restore sp */
move sp, s1