Re: [Qemu-devel] [PATCH] hw/acpi/nvdimm: Don't take address of fields in packed structs

[Peter Maydell]

Since nobody responded to my ping of a week ago I propose to just
apply this to master...

thanks
-- PMM

On 5 November 2018 at 14:40, Peter Maydell <address@hidden> wrote:
> Ping? This patch got reviewed but does not seem to have
> made it into anybody's tree.
>
> thanks
> -- PMM
>
> On 16 October 2018 at 18:52, Peter Maydell <address@hidden> wrote:
>> Taking the address of a field in a packed struct is a bad idea, because
>> it might not be actually aligned enough for that pointer type (and
>> thus cause a crash on dereference on some host architectures). Newer
>> versions of clang warn about this. Avoid the bug by not using the
>> "modify in place" byte swapping functions.
>>
>> Patch produced with scripts/coccinelle/inplace-byteswaps.cocci.
>>
>> Signed-off-by: Peter Maydell <address@hidden>
>> ---
>> Automatically generated patch, tested with "make check" only.
>>
>>  hw/acpi/nvdimm.c | 16 ++++++++--------
>>  1 file changed, 8 insertions(+), 8 deletions(-)
>>
>> diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
>> index 27eeb6609f5..e53b2cb6819 100644
>> --- a/hw/acpi/nvdimm.c
>> +++ b/hw/acpi/nvdimm.c
>> @@ -581,7 +581,7 @@ static void nvdimm_dsm_func_read_fit(AcpiNVDIMMState 
>> *state, NvdimmDsmIn *in,
>>      int size;
>>
>>      read_fit = (NvdimmFuncReadFITIn *)in->arg3;
>> -    le32_to_cpus(&read_fit->offset);
>> +    read_fit->offset = le32_to_cpu(read_fit->offset);
>>
>>      fit = fit_buf->fit;
>>
>> @@ -742,8 +742,8 @@ static void nvdimm_dsm_get_label_data(NVDIMMDevice 
>> *nvdimm, NvdimmDsmIn *in,
>>      int size;
>>
>>      get_label_data = (NvdimmFuncGetLabelDataIn *)in->arg3;
>> -    le32_to_cpus(&get_label_data->offset);
>> -    le32_to_cpus(&get_label_data->length);
>> +    get_label_data->offset = le32_to_cpu(get_label_data->offset);
>> +    get_label_data->length = le32_to_cpu(get_label_data->length);
>>
>>      nvdimm_debug("Read Label Data: offset %#x length %#x.\n",
>>                   get_label_data->offset, get_label_data->length);
>> @@ -781,8 +781,8 @@ static void nvdimm_dsm_set_label_data(NVDIMMDevice 
>> *nvdimm, NvdimmDsmIn *in,
>>
>>      set_label_data = (NvdimmFuncSetLabelDataIn *)in->arg3;
>>
>> -    le32_to_cpus(&set_label_data->offset);
>> -    le32_to_cpus(&set_label_data->length);
>> +    set_label_data->offset = le32_to_cpu(set_label_data->offset);
>> +    set_label_data->length = le32_to_cpu(set_label_data->length);
>>
>>      nvdimm_debug("Write Label Data: offset %#x length %#x.\n",
>>                   set_label_data->offset, set_label_data->length);
>> @@ -877,9 +877,9 @@ nvdimm_dsm_write(void *opaque, hwaddr addr, uint64_t 
>> val, unsigned size)
>>      in = g_new(NvdimmDsmIn, 1);
>>      cpu_physical_memory_read(dsm_mem_addr, in, sizeof(*in));
>>
>> -    le32_to_cpus(&in->revision);
>> -    le32_to_cpus(&in->function);
>> -    le32_to_cpus(&in->handle);
>> +    in->revision = le32_to_cpu(in->revision);
>> +    in->function = le32_to_cpu(in->function);
>> +    in->handle = le32_to_cpu(in->handle);
>>
>>      nvdimm_debug("Revision %#x Handler %#x Function %#x.\n", in->revision,
>>                   in->handle, in->function);
>> --