Re: [Qemu-devel] [PATCH 1/3] net/vmxnet3: return 1 on device activation failure

[Miao Yan]

2015-12-22 17:06 GMT+08:00 P J P <address@hidden>:
> +-- On Tue, 22 Dec 2015, Miao Yan wrote --+
> | > If '1' indicates the error, the 'default:' case in the same switch needs 
> to be
> | > updated too.
> |
> | '1' indicates an error on device activation. Not sure about the 'unknown
> | command' case.
>
>   Ideally it should be same, inconsistent return codes wouldn't be helpful.

ESXi returns 0 on 'unknown command', I thought we should follow here.


>
> | Linux driver uses VXMNET3_READ_BAR1_REG() which calls readl().
> | That should be an indication that the driver expects 32bit values.
>
>   Right.
>
> | But the prototype in MemoryRegionOps requires uint64_t.
>
>   That is odd. It does not seem right to use uint64_t for 32bit values, and
> then return a negative(-1) value.

I've already sent v2 patch to change this to 0. But 'read' in MemoryRegionOps
does require a uint64_t return type, to which vmxnet3_io_bar1_read()
connects. Seems 'read' handles memory access of any size.

>
>
> @Dmitry...?
> --
> Prasad J Pandit / Red Hat Product Security Team
> 47AF CE69 3A90 54AA 9045 1053 DD13 3D32 FE5B 041F