Re: [PATCH v3] fix endianness bug

[Richard Henderson]

On 4/25/24 06:41, Alexandra Diupina wrote:
> +static MemTxResult xlnx_dpdma_read_descriptor(XlnxDPDMAState *s,
> +                                    uint64_t desc_addr, DPDMADescriptor *desc)
> +{
> +    if (dma_memory_read(&address_space_memory, desc_addr, &desc,
> +                            sizeof(DPDMADescriptor), MEMTXATTRS_UNSPECIFIED))
> +        return MEMTX_ERROR;
> +

Missing { } for docs/devel/style.rst.

> +static void xlnx_dpdma_write_descriptor(uint64_t desc_addr,
> +                                                DPDMADescriptor *desc)
> +{
> +    /* Convert from host endianness into LE.  */
> +    desc->control = cpu_to_le32(desc->control);
> +    desc->descriptor_id = cpu_to_le32(desc->descriptor_id);
> +    desc->xfer_size = cpu_to_le32(desc->xfer_size);
> +    desc->line_size_stride = cpu_to_le32(desc->line_size_stride);
> +    desc->timestamp_lsb = cpu_to_le32(desc->timestamp_lsb);
> +    desc->timestamp_msb = cpu_to_le32(desc->timestamp_msb);
> +    desc->address_extension = cpu_to_le32(desc->address_extension);
> +    desc->next_descriptor = cpu_to_le32(desc->next_descriptor);
> +    desc->source_address = cpu_to_le32(desc->source_address);
> +    desc->address_extension_23 = cpu_to_le32(desc->address_extension_23);
> +    desc->address_extension_45 = cpu_to_le32(desc->address_extension_45);
> +    desc->source_address2 = cpu_to_le32(desc->source_address2);
> +    desc->source_address3 = cpu_to_le32(desc->source_address3);
> +    desc->source_address4 = cpu_to_le32(desc->source_address4);
> +    desc->source_address5 = cpu_to_le32(desc->source_address5);
> +    desc->crc = cpu_to_le32(desc->crc);

This is incorrect, rewriting in place, because after the call,

>          if (xlnx_dpdma_desc_completion_interrupt(&desc)) {

the memory block is still live, and the swap here has corrupted it.

> +
> +    dma_memory_write(&address_space_memory, desc_addr, &desc,

This is incorrect because desc is now a pointer so &desc is DPDMADescriptor **.

Do not reply to an existing thread to post a new patch.


r~