Re: [RFC PATCH v2 1/3] arch, arm: allow dom0 access to I/O memory of mapped devices

[Arianna Avanzini <avanzini.arianna@gmail.com>]

On 03/10/2014 12:30 PM, Julien Grall wrote:
> Hello Arianna,
> 

Hello,

thank you again for the feedback.


> On 03/10/2014 08:25 AM, Arianna Avanzini wrote:
>> Currently, dom0 is not allowed access to the I/O memory ranges
>> used to access devices exposed to it. This commit attempts
>> to give it access to those memory ranges during domain build
>> by adding the ranges to dom0's iomem_caps.
>>
>> Signed-off-by: Arianna Avanzini <avanzini.arianna@gmail.com>
>> Cc: Dario Faggioli <dario.faggioli@citrix.com>
>> Cc: Paolo Valente <paolo.valente@unimore.it>
>> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
>> Cc: Julien Grall <julien.grall@citrix.com>
>> Cc: Ian Campbell <Ian.Campbell@eu.citrix.com>
>> Cc: Ian Jackson <Ian.Jackson@eu.citrix.com>
>> Cc: Eric Trudeau <etrudeau@broadcom.com>
>> Cc: Viktor Kleinik <viktor.kleinik@globallogic.com>
>> ---
>>  xen/arch/arm/domain_build.c | 10 ++++++++++
>>  1 file changed, 10 insertions(+)
>>
>> diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
>> index 5ca2f15..0b283d8 100644
>> --- a/xen/arch/arm/domain_build.c
>> +++ b/xen/arch/arm/domain_build.c
>> @@ -11,6 +11,7 @@
>>  #include <xen/device_tree.h>
>>  #include <xen/libfdt/libfdt.h>
>>  #include <xen/guest_access.h>
>> +#include <xen/iocap.h>
>>  #include <asm/setup.h>
>>  #include <asm/platform.h>
>>  #include <asm/psci.h>
>> @@ -733,6 +734,15 @@ static int map_device(struct domain *d, const struct dt_device_node *dev)
>>          DPRINT("addr %u = 0x%"PRIx64" - 0x%"PRIx64"\n",
>>                 i, addr, addr + size - 1);
>>  
>> +        res = iomem_permit_access(d, paddr_to_pfn(addr & PAGE_MASK),
>> +                                  paddr_to_pfn(PAGE_ALIGN(addr + size - 1)));
>> +        if ( res )
>> +        {
>> +            printk(XENLOG_ERR "Unable to permit to dom0 access to"
> 
> Can you print the right domain id instead of using "dom0"?
> 

Sure, thank you for pointing that out.


> I have a patch to remove the other hardcoded "dom0" in this function.
> 
> Regards,
> 


-- 
/*
 * Arianna Avanzini
 * avanzini.arianna@gmail.com
 * 73628@studenti.unimore.it
 */