Re: [PATCH v2] MIPS: jump_label: Fix compat branch range check

From: Thomas Bogendoerfer
Date: Fri Nov 11 2022 - 10:09:17 EST


On Thu, Nov 03, 2022 at 03:10:53PM +0000, Jiaxun Yang wrote:
> Cast upper bound of branch range to long to do signed compare,
> avoid negative offset trigger this warning.
>
> Fixes: 9b6584e35f40 ("MIPS: jump_label: Use compact branches for >= r6")
> Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Reviewed-by: Philippe Mathieu-Daudé <philmd@xxxxxxxxxx>
> ---
> v2: Fix typo, collect review tags.
> ---
> arch/mips/kernel/jump_label.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/mips/kernel/jump_label.c b/arch/mips/kernel/jump_label.c
> index 71a882c8c6eb..f7978d50a2ba 100644
> --- a/arch/mips/kernel/jump_label.c
> +++ b/arch/mips/kernel/jump_label.c
> @@ -56,7 +56,7 @@ void arch_jump_label_transform(struct jump_entry *e,
> * The branch offset must fit in the instruction's 26
> * bit field.
> */
> - WARN_ON((offset >= BIT(25)) ||
> + WARN_ON((offset >= (long)BIT(25)) ||
> (offset < -(long)BIT(25)));
>
> insn.j_format.opcode = bc6_op;
> --
> 2.34.1

applied to mips-fixes.

Thomas.

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