Re: [PATCH v6 2/8] powerpc/watchpoint: Fix handling of vector instructions

[Rogerio Alves]

On 9/2/20 1:29 AM, Ravi Bangoria wrote:
> Vector load/store instructions are special because they are always
> aligned. Thus unaligned EA needs to be aligned down before comparing
> it with watch ranges. Otherwise we might consider valid event as
> invalid.
>
> Fixes: 74c6881019b7 ("powerpc/watchpoint: Prepare handler to handle more than one watchpoint")
> Signed-off-by: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxx>
Tested-by: Rogerio Alves <rcardoso@xxxxxxxxxxxxx>
> ---
>   arch/powerpc/kernel/hw_breakpoint.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/arch/powerpc/kernel/hw_breakpoint.c b/arch/powerpc/kernel/hw_breakpoint.c
> index 9f7df1c37233..f6b24838ca3c 100644
> --- a/arch/powerpc/kernel/hw_breakpoint.c
> +++ b/arch/powerpc/kernel/hw_breakpoint.c
> @@ -644,6 +644,8 @@ static void get_instr_detail(struct pt_regs *regs, struct ppc_inst *instr,
>   	if (*type == CACHEOP) {
>   		*size = cache_op_size();
>   		*ea &= ~(*size - 1);
> +	} else if (*type == LOAD_VMX || *type == STORE_VMX) {
> +		*ea &= ~(*size - 1);
>   	}
>   }
>