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Jan Beulich

2013-Jun-03 07:12 UTC

AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

The code this patch added is redundant with already present code in
set_iommu_{command_buffer,{event,ppr}_log}_control(). Just switch those
ones from using writel() to writeq() for consistency.

Signed-off-by: Jan Beulich <jbeulich@suse.com>

--- a/xen/drivers/passthrough/amd/iommu_init.c
+++ b/xen/drivers/passthrough/amd/iommu_init.c
@@ -154,11 +154,6 @@ static void register_iommu_cmd_buffer_in
                          IOMMU_CMD_BUFFER_LENGTH_MASK,
                          IOMMU_CMD_BUFFER_LENGTH_SHIFT, &entry);
     writel(entry, iommu->mmio_base+IOMMU_CMD_BUFFER_BASE_HIGH_OFFSET);
-
-    /* Reset head/tail pointer. SR56x0 Erratum 64 means this might not happen
-     * automatically for us. */
-    writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_HEAD_OFFSET);
-    writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_TAIL_OFFSET);
 }
 
 static void register_iommu_event_log_in_mmio_space(struct amd_iommu *iommu)
@@ -187,11 +182,6 @@ static void register_iommu_event_log_in_
                         IOMMU_EVENT_LOG_LENGTH_MASK,
                         IOMMU_EVENT_LOG_LENGTH_SHIFT, &entry);
     writel(entry, iommu->mmio_base+IOMMU_EVENT_LOG_BASE_HIGH_OFFSET);
-
-    /* Reset head/tail pointer. SR56x0 Erratum 64 means this might not happen
-     * automatically for us. */
-    writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_HEAD_OFFSET);
-    writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_TAIL_OFFSET);
 }
 
 static void register_iommu_ppr_log_in_mmio_space(struct amd_iommu *iommu)
@@ -220,9 +210,6 @@ static void register_iommu_ppr_log_in_mm
                         IOMMU_PPR_LOG_LENGTH_MASK,
                         IOMMU_PPR_LOG_LENGTH_SHIFT, &entry);
     writel(entry, iommu->mmio_base + IOMMU_PPR_LOG_BASE_HIGH_OFFSET);
-
-    writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
-    writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
 }
 
 
@@ -267,8 +254,8 @@ static void set_iommu_command_buffer_con
     /*reset head and tail pointer manually before enablement */
     if ( enable )
     {
-        writel(0x0, iommu->mmio_base + IOMMU_CMD_BUFFER_HEAD_OFFSET);
-        writel(0x0, iommu->mmio_base + IOMMU_CMD_BUFFER_TAIL_OFFSET);
+        writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_HEAD_OFFSET);
+        writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_TAIL_OFFSET);
 
         iommu_set_bit(&entry, IOMMU_CONTROL_COMMAND_BUFFER_ENABLE_SHIFT);
     }
@@ -326,8 +313,8 @@ static void set_iommu_event_log_control(
     /*reset head and tail pointer manually before enablement */
     if ( enable )
     {
-        writel(0x0, iommu->mmio_base + IOMMU_EVENT_LOG_HEAD_OFFSET);
-        writel(0x0, iommu->mmio_base + IOMMU_EVENT_LOG_TAIL_OFFSET);
+        writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_HEAD_OFFSET);
+        writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_TAIL_OFFSET);
 
         iommu_set_bit(&entry, IOMMU_CONTROL_EVENT_LOG_INT_SHIFT);
         iommu_set_bit(&entry, IOMMU_CONTROL_EVENT_LOG_ENABLE_SHIFT);
@@ -353,8 +340,8 @@ static void set_iommu_ppr_log_control(st
     /*reset head and tail pointer manually before enablement */
     if ( enable )
     {
-        writel(0x0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
-        writel(0x0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
+        writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
+        writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
 
         iommu_set_bit(&entry, IOMMU_CONTROL_PPR_ENABLE_SHIFT);
         iommu_set_bit(&entry, IOMMU_CONTROL_PPR_INT_SHIFT);





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Andrew Cooper

2013-Jun-03 09:43 UTC

head link

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

On 03/06/13 08:12, Jan Beulich wrote:> The code this patch added is redundant with already present code in
> set_iommu_{command_buffer,{event,ppr}_log}_control(). Just switch those
> ones from using writel() to writeq() for consistency.
>
> Signed-off-by: Jan Beulich <jbeulich@suse.com>
Yikes - I clearly didn''t do a good job looking to see whether this
issue
had already been addressed.

Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
>
> --- a/xen/drivers/passthrough/amd/iommu_init.c
> +++ b/xen/drivers/passthrough/amd/iommu_init.c
> @@ -154,11 +154,6 @@ static void register_iommu_cmd_buffer_in
>                           IOMMU_CMD_BUFFER_LENGTH_MASK,
>                           IOMMU_CMD_BUFFER_LENGTH_SHIFT, &entry);
>      writel(entry, iommu->mmio_base+IOMMU_CMD_BUFFER_BASE_HIGH_OFFSET);
> -
> -    /* Reset head/tail pointer. SR56x0 Erratum 64 means this might not
happen
> -     * automatically for us. */
> -    writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_HEAD_OFFSET);
> -    writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_TAIL_OFFSET);
>  }
>  
>  static void register_iommu_event_log_in_mmio_space(struct amd_iommu
*iommu)
> @@ -187,11 +182,6 @@ static void register_iommu_event_log_in_
>                          IOMMU_EVENT_LOG_LENGTH_MASK,
>                          IOMMU_EVENT_LOG_LENGTH_SHIFT, &entry);
>      writel(entry, iommu->mmio_base+IOMMU_EVENT_LOG_BASE_HIGH_OFFSET);
> -
> -    /* Reset head/tail pointer. SR56x0 Erratum 64 means this might not
happen
> -     * automatically for us. */
> -    writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_HEAD_OFFSET);
> -    writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_TAIL_OFFSET);
>  }
>  
>  static void register_iommu_ppr_log_in_mmio_space(struct amd_iommu *iommu)
> @@ -220,9 +210,6 @@ static void register_iommu_ppr_log_in_mm
>                          IOMMU_PPR_LOG_LENGTH_MASK,
>                          IOMMU_PPR_LOG_LENGTH_SHIFT, &entry);
>      writel(entry, iommu->mmio_base + IOMMU_PPR_LOG_BASE_HIGH_OFFSET);
> -
> -    writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
> -    writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
>  }
>  
>  
> @@ -267,8 +254,8 @@ static void set_iommu_command_buffer_con
>      /*reset head and tail pointer manually before enablement */
>      if ( enable )
>      {
> -        writel(0x0, iommu->mmio_base + IOMMU_CMD_BUFFER_HEAD_OFFSET);
> -        writel(0x0, iommu->mmio_base + IOMMU_CMD_BUFFER_TAIL_OFFSET);
> +        writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_HEAD_OFFSET);
> +        writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_TAIL_OFFSET);
>  
>          iommu_set_bit(&entry,
IOMMU_CONTROL_COMMAND_BUFFER_ENABLE_SHIFT);
>      }
> @@ -326,8 +313,8 @@ static void set_iommu_event_log_control(
>      /*reset head and tail pointer manually before enablement */
>      if ( enable )
>      {
> -        writel(0x0, iommu->mmio_base + IOMMU_EVENT_LOG_HEAD_OFFSET);
> -        writel(0x0, iommu->mmio_base + IOMMU_EVENT_LOG_TAIL_OFFSET);
> +        writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_HEAD_OFFSET);
> +        writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_TAIL_OFFSET);
>  
>          iommu_set_bit(&entry, IOMMU_CONTROL_EVENT_LOG_INT_SHIFT);
>          iommu_set_bit(&entry, IOMMU_CONTROL_EVENT_LOG_ENABLE_SHIFT);
> @@ -353,8 +340,8 @@ static void set_iommu_ppr_log_control(st
>      /*reset head and tail pointer manually before enablement */
>      if ( enable )
>      {
> -        writel(0x0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
> -        writel(0x0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
> +        writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
> +        writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
>  
>          iommu_set_bit(&entry, IOMMU_CONTROL_PPR_ENABLE_SHIFT);
>          iommu_set_bit(&entry, IOMMU_CONTROL_PPR_INT_SHIFT);
>
>
>

Suravee Suthikulpanit

2013-Jun-04 04:41 UTC

head link

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

Sorry, I also missed that :(

Suravee

On 6/3/2013 4:43 AM, Andrew Cooper wrote:> On 03/06/13 08:12, Jan Beulich wrote:
>> The code this patch added is redundant with already present code in
>> set_iommu_{command_buffer,{event,ppr}_log}_control(). Just switch those
>> ones from using writel() to writeq() for consistency.
>>
>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> Yikes - I clearly didn''t do a good job looking to see whether this
issue
> had already been addressed.
>
> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
>
>> --- a/xen/drivers/passthrough/amd/iommu_init.c
>> +++ b/xen/drivers/passthrough/amd/iommu_init.c
>> @@ -154,11 +154,6 @@ static void register_iommu_cmd_buffer_in
>>                            IOMMU_CMD_BUFFER_LENGTH_MASK,
>>                            IOMMU_CMD_BUFFER_LENGTH_SHIFT, &entry);
>>       writel(entry,
iommu->mmio_base+IOMMU_CMD_BUFFER_BASE_HIGH_OFFSET);
>> -
>> -    /* Reset head/tail pointer. SR56x0 Erratum 64 means this might not
happen
>> -     * automatically for us. */
>> -    writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_HEAD_OFFSET);
>> -    writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_TAIL_OFFSET);
>>   }
>>   
>>   static void register_iommu_event_log_in_mmio_space(struct amd_iommu
*iommu)
>> @@ -187,11 +182,6 @@ static void register_iommu_event_log_in_
>>                           IOMMU_EVENT_LOG_LENGTH_MASK,
>>                           IOMMU_EVENT_LOG_LENGTH_SHIFT, &entry);
>>       writel(entry,
iommu->mmio_base+IOMMU_EVENT_LOG_BASE_HIGH_OFFSET);
>> -
>> -    /* Reset head/tail pointer. SR56x0 Erratum 64 means this might not
happen
>> -     * automatically for us. */
>> -    writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_HEAD_OFFSET);
>> -    writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_TAIL_OFFSET);
>>   }
>>   
>>   static void register_iommu_ppr_log_in_mmio_space(struct amd_iommu
*iommu)
>> @@ -220,9 +210,6 @@ static void register_iommu_ppr_log_in_mm
>>                           IOMMU_PPR_LOG_LENGTH_MASK,
>>                           IOMMU_PPR_LOG_LENGTH_SHIFT, &entry);
>>       writel(entry, iommu->mmio_base +
IOMMU_PPR_LOG_BASE_HIGH_OFFSET);
>> -
>> -    writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
>> -    writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
>>   }
>>   
>>   
>> @@ -267,8 +254,8 @@ static void set_iommu_command_buffer_con
>>       /*reset head and tail pointer manually before enablement */
>>       if ( enable )
>>       {
>> -        writel(0x0, iommu->mmio_base +
IOMMU_CMD_BUFFER_HEAD_OFFSET);
>> -        writel(0x0, iommu->mmio_base +
IOMMU_CMD_BUFFER_TAIL_OFFSET);
>> +        writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_HEAD_OFFSET);
>> +        writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_TAIL_OFFSET);
>>   
>>           iommu_set_bit(&entry,
IOMMU_CONTROL_COMMAND_BUFFER_ENABLE_SHIFT);
>>       }
>> @@ -326,8 +313,8 @@ static void set_iommu_event_log_control(
>>       /*reset head and tail pointer manually before enablement */
>>       if ( enable )
>>       {
>> -        writel(0x0, iommu->mmio_base +
IOMMU_EVENT_LOG_HEAD_OFFSET);
>> -        writel(0x0, iommu->mmio_base +
IOMMU_EVENT_LOG_TAIL_OFFSET);
>> +        writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_HEAD_OFFSET);
>> +        writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_TAIL_OFFSET);
>>   
>>           iommu_set_bit(&entry, IOMMU_CONTROL_EVENT_LOG_INT_SHIFT);
>>           iommu_set_bit(&entry,
IOMMU_CONTROL_EVENT_LOG_ENABLE_SHIFT);
>> @@ -353,8 +340,8 @@ static void set_iommu_ppr_log_control(st
>>       /*reset head and tail pointer manually before enablement */
>>       if ( enable )
>>       {
>> -        writel(0x0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
>> -        writel(0x0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
>> +        writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
>> +        writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
>>   
>>           iommu_set_bit(&entry, IOMMU_CONTROL_PPR_ENABLE_SHIFT);
>>           iommu_set_bit(&entry, IOMMU_CONTROL_PPR_INT_SHIFT);
>>
>>
>>
>

Jan Beulich

2013-Jun-04 06:33 UTC

head link

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

>>> On 04.06.13 at 06:41, Suravee Suthikulpanit
<suravee.suthikulpanit@amd.com> wrote:
> Sorry, I also missed that :(
Is this an unusual form of an acked-by/reviewed-by?

Jan
> On 6/3/2013 4:43 AM, Andrew Cooper wrote:
>> On 03/06/13 08:12, Jan Beulich wrote:
>>> The code this patch added is redundant with already present code in
>>> set_iommu_{command_buffer,{event,ppr}_log}_control(). Just switch
those
>>> ones from using writel() to writeq() for consistency.
>>>
>>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
>> Yikes - I clearly didn''t do a good job looking to see whether
this issue
>> had already been addressed.
>>
>> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
>>
>>> --- a/xen/drivers/passthrough/amd/iommu_init.c
>>> +++ b/xen/drivers/passthrough/amd/iommu_init.c
>>> @@ -154,11 +154,6 @@ static void register_iommu_cmd_buffer_in
>>>                            IOMMU_CMD_BUFFER_LENGTH_MASK,
>>>                            IOMMU_CMD_BUFFER_LENGTH_SHIFT,
&entry);
>>>       writel(entry,
iommu->mmio_base+IOMMU_CMD_BUFFER_BASE_HIGH_OFFSET);
>>> -
>>> -    /* Reset head/tail pointer. SR56x0 Erratum 64 means this might
not
> happen
>>> -     * automatically for us. */
>>> -    writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_HEAD_OFFSET);
>>> -    writeq(0, iommu->mmio_base + IOMMU_CMD_BUFFER_TAIL_OFFSET);
>>>   }
>>>   
>>>   static void register_iommu_event_log_in_mmio_space(struct
amd_iommu
> *iommu)
>>> @@ -187,11 +182,6 @@ static void register_iommu_event_log_in_
>>>                           IOMMU_EVENT_LOG_LENGTH_MASK,
>>>                           IOMMU_EVENT_LOG_LENGTH_SHIFT,
&entry);
>>>       writel(entry,
iommu->mmio_base+IOMMU_EVENT_LOG_BASE_HIGH_OFFSET);
>>> -
>>> -    /* Reset head/tail pointer. SR56x0 Erratum 64 means this might
not
> happen
>>> -     * automatically for us. */
>>> -    writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_HEAD_OFFSET);
>>> -    writeq(0, iommu->mmio_base + IOMMU_EVENT_LOG_TAIL_OFFSET);
>>>   }
>>>   
>>>   static void register_iommu_ppr_log_in_mmio_space(struct amd_iommu
*iommu)
>>> @@ -220,9 +210,6 @@ static void register_iommu_ppr_log_in_mm
>>>                           IOMMU_PPR_LOG_LENGTH_MASK,
>>>                           IOMMU_PPR_LOG_LENGTH_SHIFT, &entry);
>>>       writel(entry, iommu->mmio_base +
IOMMU_PPR_LOG_BASE_HIGH_OFFSET);
>>> -
>>> -    writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_HEAD_OFFSET);
>>> -    writeq(0, iommu->mmio_base + IOMMU_PPR_LOG_TAIL_OFFSET);
>>>   }
>>>   
>>>   
>>> @@ -267,8 +254,8 @@ static void set_iommu_command_buffer_con
>>>       /*reset head and tail pointer manually before enablement */
>>>       if ( enable )
>>>       {
>>> -        writel(0x0, iommu->mmio_base +
IOMMU_CMD_BUFFER_HEAD_OFFSET);
>>> -        writel(0x0, iommu->mmio_base +
IOMMU_CMD_BUFFER_TAIL_OFFSET);
>>> +        writeq(0, iommu->mmio_base +
IOMMU_CMD_BUFFER_HEAD_OFFSET);
>>> +        writeq(0, iommu->mmio_base +
IOMMU_CMD_BUFFER_TAIL_OFFSET);
>>>   
>>>           iommu_set_bit(&entry,
IOMMU_CONTROL_COMMAND_BUFFER_ENABLE_SHIFT);
>>>       }
>>> @@ -326,8 +313,8 @@ static void set_iommu_event_log_control(
>>>       /*reset head and tail pointer manually before enablement */
>>>       if ( enable )
>>>       {
>>> -        writel(0x0, iommu->mmio_base +
IOMMU_EVENT_LOG_HEAD_OFFSET);
>>> -        writel(0x0, iommu->mmio_base +
IOMMU_EVENT_LOG_TAIL_OFFSET);
>>> +        writeq(0, iommu->mmio_base +
IOMMU_EVENT_LOG_HEAD_OFFSET);
>>> +        writeq(0, iommu->mmio_base +
IOMMU_EVENT_LOG_TAIL_OFFSET);
>>>   
>>>           iommu_set_bit(&entry,
IOMMU_CONTROL_EVENT_LOG_INT_SHIFT);
>>>           iommu_set_bit(&entry,
IOMMU_CONTROL_EVENT_LOG_ENABLE_SHIFT);
>>> @@ -353,8 +340,8 @@ static void set_iommu_ppr_log_control(st
>>>       /*reset head and tail pointer manually before enablement */
>>>       if ( enable )
>>>       {
>>> -        writel(0x0, iommu->mmio_base +
IOMMU_PPR_LOG_HEAD_OFFSET);
>>> -        writel(0x0, iommu->mmio_base +
IOMMU_PPR_LOG_TAIL_OFFSET);
>>> +        writeq(0, iommu->mmio_base +
IOMMU_PPR_LOG_HEAD_OFFSET);
>>> +        writeq(0, iommu->mmio_base +
IOMMU_PPR_LOG_TAIL_OFFSET);
>>>   
>>>           iommu_set_bit(&entry,
IOMMU_CONTROL_PPR_ENABLE_SHIFT);
>>>           iommu_set_bit(&entry, IOMMU_CONTROL_PPR_INT_SHIFT);
>>>
>>>
>>>
>>

George Dunlap

2013-Jun-04 09:24 UTC

head link

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

On Mon, Jun 3, 2013 at 10:43 AM, Andrew Cooper
<andrew.cooper3@citrix.com> wrote:> On 03/06/13 08:12, Jan Beulich wrote:
>> The code this patch added is redundant with already present code in
>> set_iommu_{command_buffer,{event,ppr}_log}_control(). Just switch those
>> ones from using writel() to writeq() for consistency.
>>
>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
>
> Yikes - I clearly didn''t do a good job looking to see whether this
issue
> had already been addressed.
>
> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
You couldn''t make this an "Acked-by", could you?

 -George

Andrew Cooper

2013-Jun-04 09:30 UTC

head link

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

On 04/06/13 10:24, George Dunlap wrote:> On Mon, Jun 3, 2013 at 10:43 AM, Andrew Cooper
> <andrew.cooper3@citrix.com> wrote:
>> On 03/06/13 08:12, Jan Beulich wrote:
>>> The code this patch added is redundant with already present code in
>>> set_iommu_{command_buffer,{event,ppr}_log}_control(). Just switch
those
>>> ones from using writel() to writeq() for consistency.
>>>
>>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
>> Yikes - I clearly didn''t do a good job looking to see whether
this issue
>> had already been addressed.
>>
>> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
> You couldn''t make this an "Acked-by", could you?
>
>  -George
I could do that, but as I am not a maintainer, I was under the
impression that reviewed-by was my preferred way of saying "I think this
is sensible".

~Andrew

George Dunlap

2013-Jun-04 09:38 UTC

head link

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

On 06/04/2013 10:30 AM, Andrew Cooper wrote:> On 04/06/13 10:24, George Dunlap wrote:
>> On Mon, Jun 3, 2013 at 10:43 AM, Andrew Cooper
>> <andrew.cooper3@citrix.com> wrote:
>>> On 03/06/13 08:12, Jan Beulich wrote:
>>>> The code this patch added is redundant with already present
code in
>>>> set_iommu_{command_buffer,{event,ppr}_log}_control(). Just
switch those
>>>> ones from using writel() to writeq() for consistency.
>>>>
>>>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
>>> Yikes - I clearly didn''t do a good job looking to see
whether this issue
>>> had already been addressed.
>>>
>>> Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
>> You couldn''t make this an "Acked-by", could you?
>>
>>   -George
>
> I could do that, but as I am not a maintainer, I was under the
> impression that reviewed-by was my preferred way of saying "I think
this
> is sensible".
In this context, I would read "Acked-by" as "I agree that this
should go
in", or at very least, "I am happy for this to go in"; whereas to
me
"Reviewed-by" to me sounds like, "I took a close look at the code
and
didn''t see anything wrong, but otherwise have no opinion on the
matter."

But maybe I''m behind the times here. :-)

  -George

Ian Campbell

2013-Jun-04 09:53 UTC

head link

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

On Tue, 2013-06-04 at 10:38 +0100, George Dunlap wrote:> In this context, I would read "Acked-by" as "I agree that
this should go
> in", or at very least, "I am happy for this to go in";
whereas to me
> "Reviewed-by" to me sounds like, "I took a close look at the
code and
> didn''t see anything wrong, but otherwise have no opinion on the
matter."
I think we decided (somewhat informally I think) that we interpreted
Foo-by according to Linux''s Documentation/SubmittingPatches:

If a person was not directly involved in the preparation or handling of
a
patch but wishes to signify and record their approval of it then they
can
arrange to have an Acked-by: line added to the patch''s
changelog.

Acked-by: is often used by the maintainer of the affected code when that
maintainer neither contributed to nor forwarded the patch.

Acked-by: is not as formal as Signed-off-by:. It is a record that the
acker
has at least reviewed the patch and has indicated acceptance. Hence
patch
mergers will sometimes manually convert an acker''s "yep,
looks good to me"
into an Acked-by:.

Acked-by: does not necessarily indicate acknowledgement of the entire
patch.
For example, if a patch affects multiple subsystems and has an Acked-by:
from
one subsystem maintainer then this usually indicates acknowledgement of
just
the part which affects that maintainer''s code. Judgement
should be used here.
When in doubt people should refer to the original discussion in the
mailing
list archives.

[...]

Reviewed-by is somehow more formal:

Reviewed-by:, instead, indicates that the patch has been reviewed and
found
acceptable according to the Reviewer''s Statement:

Reviewer''s statement of oversight

By offering my Reviewed-by: tag, I state that:

(a) I have carried out a technical review of this patch to
evaluate its appropriateness and readiness for inclusion
into
the mainline kernel.

(b) Any problems, concerns, or questions relating to the patch
have been communicated back to the submitter. I am
satisfied
with the submitter''s response to my comments.

(c) While there may be things that could be improved with this
submission, I believe that it is, at this time, (1) a
worthwhile modification to the kernel, and (2) free of
known
issues which would argue against its inclusion.

(d) While I have reviewed the patch and believe it to be sound,
I
do not (unless explicitly stated elsewhere) make any
warranties or guarantees that it will achieve its stated
purpose or function properly in any given situation.

A Reviewed-by tag is a statement of opinion that the patch is an
appropriate modification of the kernel without any remaining serious
technical issues. Any interested reviewer (who has done the work) can
offer a Reviewed-by tag for a patch. This tag serves to give credit to
reviewers and to inform maintainers of the degree of review which has
been
done on the patch. Reviewed-by: tags, when supplied by reviewers known
to
understand the subject area and to perform thorough reviews, will
normally
increase the likelihood of your patch getting into the kernel.

Acked-by is supposedly something which is offered by the maintainer of
the relevant code to indicate they are happy for it to go in. In the
Linux world that might be via a different maintainer''s tree (for cross
subsystem stuff) or be an indication from e.g. a driver maintainer to
the subsystem maintainer that the patch can be applied. In the Xen world
I think we interpret an Ack from someone in MAINTAINERS as a signal to
the committers that the patch should be committed.

Ian.

George Dunlap

2013-Jun-04 09:56 UTC

head link

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

On 06/04/2013 10:53 AM, Ian Campbell wrote:> On Tue, 2013-06-04 at 10:38 +0100, George Dunlap wrote:
>> In this context, I would read "Acked-by" as "I agree
that this should go
>> in", or at very least, "I am happy for this to go in";
whereas to me
>> "Reviewed-by" to me sounds like, "I took a close look at
the code and
>> didn''t see anything wrong, but otherwise have no opinion on
the matter."
>
> I think we decided (somewhat informally I think) that we interpreted
> Foo-by according to Linux''s Documentation/SubmittingPatches:
>
>          If a person was not directly involved in the preparation or
handling of a
>          patch but wishes to signify and record their approval of it then
they can
>          arrange to have an Acked-by: line added to the patch''s
changelog.
>
>          Acked-by: is often used by the maintainer of the affected code
when that
>          maintainer neither contributed to nor forwarded the patch.
>
>          Acked-by: is not as formal as Signed-off-by:.  It is a record that
the acker
>          has at least reviewed the patch and has indicated acceptance. 
Hence patch
>          mergers will sometimes manually convert an acker''s
"yep, looks good to me"
>          into an Acked-by:.
>
>          Acked-by: does not necessarily indicate acknowledgement of the
entire patch.
>          For example, if a patch affects multiple subsystems and has an
Acked-by: from
>          one subsystem maintainer then this usually indicates
acknowledgement of just
>          the part which affects that maintainer''s code.  Judgement
should be used here.
>          When in doubt people should refer to the original discussion in
the mailing
>          list archives.
>
>          [...]
>
> Reviewed-by is somehow more formal:
>
>          Reviewed-by:, instead, indicates that the patch has been reviewed
and found
>          acceptable according to the Reviewer''s Statement:
>
>                  Reviewer''s statement of oversight
>
>                  By offering my Reviewed-by: tag, I state that:
>
>                   (a) I have carried out a technical review of this patch
to
>                       evaluate its appropriateness and readiness for
inclusion into
>                       the mainline kernel.
>
>                   (b) Any problems, concerns, or questions relating to the
patch
>                       have been communicated back to the submitter.  I am
satisfied
>                       with the submitter''s response to my
comments.
>
>                   (c) While there may be things that could be improved with
this
>                       submission, I believe that it is, at this time, (1) a
>                       worthwhile modification to the kernel, and (2) free
of known
>                       issues which would argue against its inclusion.
>
>                   (d) While I have reviewed the patch and believe it to be
sound, I
>                       do not (unless explicitly stated elsewhere) make any
>                       warranties or guarantees that it will achieve its
stated
>                       purpose or function properly in any given situation.
>
>          A Reviewed-by tag is a statement of opinion that the patch is an
>          appropriate modification of the kernel without any remaining
serious
>          technical issues.  Any interested reviewer (who has done the work)
can
>          offer a Reviewed-by tag for a patch.  This tag serves to give
credit to
>          reviewers and to inform maintainers of the degree of review which
has been
>          done on the patch.  Reviewed-by: tags, when supplied by reviewers
known to
>          understand the subject area and to perform thorough reviews, will
normally
>          increase the likelihood of your patch getting into the kernel.
>
> Acked-by is supposedly something which is offered by the maintainer of
> the relevant code to indicate they are happy for it to go in. In the
> Linux world that might be via a different maintainer''s tree (for
cross
> subsystem stuff) or be an indication from e.g. a driver maintainer to
> the subsystem maintainer that the patch can be applied. In the Xen world
> I think we interpret an Ack from someone in MAINTAINERS as a signal to
> the committers that the patch should be committed.
I stand corrected.

  -G

Suravee Suthikulpanit

2013-Jun-05 06:53 UTC

head link

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

On 6/4/2013 1:33 AM, Jan Beulich wrote:>>>> On 04.06.13 at 06:41, Suravee Suthikulpanit
<suravee.suthikulpanit@amd.com> wrote:
>> Sorry, I also missed that :(
> Is this an unusual form of an acked-by/reviewed-by?
>
> JanAcked-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>

Thanks,

Suravee

Xen devel - Jun 2013 - AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"

Re: AMD/IOMMU: revert "SR56x0 Erratum 64 - Reset all head & tail pointers"