Re: [PATCHv4 06/10] xen: Switch to using __pa_symbol

From: Laura Abbott
Date: Tue Nov 29 2016 - 17:43:14 EST


On 11/29/2016 02:26 PM, Boris Ostrovsky wrote:
> On 11/29/2016 01:55 PM, Laura Abbott wrote:
>> __pa_symbol is the correct macro to use on kernel
>> symbols. Switch to this from __pa.
>>
>> Signed-off-by: Laura Abbott <labbott@xxxxxxxxxx>
>> ---
>> Found during a sweep of the kernel. Untested.
>> ---
>> drivers/xen/xenbus/xenbus_dev_backend.c | 2 +-
>> drivers/xen/xenfs/xenstored.c | 2 +-
>> 2 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/xen/xenbus/xenbus_dev_backend.c b/drivers/xen/xenbus/xenbus_dev_backend.c
>> index 4a41ac9..31ca2bf 100644
>> --- a/drivers/xen/xenbus/xenbus_dev_backend.c
>> +++ b/drivers/xen/xenbus/xenbus_dev_backend.c
>> @@ -99,7 +99,7 @@ static int xenbus_backend_mmap(struct file *file, struct vm_area_struct *vma)
>> return -EINVAL;
>>
>> if (remap_pfn_range(vma, vma->vm_start,
>> - virt_to_pfn(xen_store_interface),
>> + PHYS_PFN(__pa_symbol(xen_store_interface)),
>> size, vma->vm_page_prot))
>> return -EAGAIN;
>>
>> diff --git a/drivers/xen/xenfs/xenstored.c b/drivers/xen/xenfs/xenstored.c
>> index fef20db..21009ea 100644
>> --- a/drivers/xen/xenfs/xenstored.c
>> +++ b/drivers/xen/xenfs/xenstored.c
>> @@ -38,7 +38,7 @@ static int xsd_kva_mmap(struct file *file, struct vm_area_struct *vma)
>> return -EINVAL;
>>
>> if (remap_pfn_range(vma, vma->vm_start,
>> - virt_to_pfn(xen_store_interface),
>> + PHYS_PFN(__pa_symbol(xen_store_interface)),
>> size, vma->vm_page_prot))
>> return -EAGAIN;
>>
>
>
> I suspect this won't work --- xen_store_interface doesn't point to a
> kernel symbol.
>
> -boris
>

I reviewed this again and yes you are right. I missed that this
was a pointer and not just a symbol so I think this patch can
just be dropped.

Thanks,
Laura