Hi James,
On 03/02/18 00:36, James Hogan wrote:
> Commit 17278a91e04f ("MIPS: CPS: Fix r1 .set mt assembler warning")
> added .set MIPS_ISA_LEVEL_RAW to silence warnings about .set mt on r1,
> however this can result in a MOVE being encoded as a 64-bit DADDU
> instruction on certain version of binutils (e.g. 2.22), and reserved
> instruction exceptions at runtime on 32-bit hardware.
>
> Reduce the sizes of the push/pop sections to include only instructions
> that are part of the MT ASE or which won't convert to 64-bit
> instructions after .set mips64r2/mips64r6.
>
> Reported-by: Greg Ungerer <gerg@xxxxxxxxxxxxxx>
> Fixes: 17278a91e04f ("MIPS: CPS: Fix r1 .set mt assembler warning")
> Signed-off-by: James Hogan <jhogan@xxxxxxxxxx>
> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
> Cc: Paul Burton <paul.burton@xxxxxxxx>
> Cc: linux-mips@xxxxxxxxxxxxxx
> Cc: <stable@xxxxxxxxxxxxxxx> # 4.15
> ---
> Greg: Please can you test this patch.
Tested and works. Thanks for the quick response and turn around.
Tested-by: Greg Ungerer <gerg@xxxxxxxxxxxxxx>
Regards
Greg
> ---
> arch/mips/kernel/cps-vec.S | 17 ++++++++++++-----
> 1 file changed, 12 insertions(+), 5 deletions(-)
>
> diff --git a/arch/mips/kernel/cps-vec.S b/arch/mips/kernel/cps-vec.S
> index e68e6e04063a..1025f937ab0e 100644
> --- a/arch/mips/kernel/cps-vec.S
> +++ b/arch/mips/kernel/cps-vec.S
> @@ -388,15 +388,16 @@ LEAF(mips_cps_boot_vpes)
>
> #elif defined(CONFIG_MIPS_MT)
>
> - .set push
> - .set MIPS_ISA_LEVEL_RAW
> - .set mt
> -
> /* If the core doesn't support MT then return */
> has_mt t0, 5f
>
> /* Enter VPE configuration state */
> + .set push
> + .set MIPS_ISA_LEVEL_RAW
> + .set mt
> dvpe
> + .set pop
> +
> PTR_LA t1, 1f
> jr.hb t1
> nop
> @@ -422,6 +423,10 @@ LEAF(mips_cps_boot_vpes)
> mtc0 t0, CP0_VPECONTROL
> ehb
>
> + .set push
> + .set MIPS_ISA_LEVEL_RAW
> + .set mt
> +
> /* Skip the VPE if its TC is not halted */
> mftc0 t0, CP0_TCHALT
> beqz t0, 2f
> @@ -495,6 +500,8 @@ LEAF(mips_cps_boot_vpes)
> ehb
> evpe
>
> + .set pop
> +
> /* Check whether this VPE is meant to be running */
> li t0, 1
> sll t0, t0, a1
> @@ -509,7 +516,7 @@ LEAF(mips_cps_boot_vpes)
> 1: jr.hb t0
> nop
>
> -2: .set pop
> +2:
>
> #endif /* CONFIG_MIPS_MT_SMP */
>
>
