* Re: [Cocci] [PATCH v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
@ 2020-07-21 9:58 ` Julia Lawall
0 siblings, 0 replies; 19+ messages in thread
From: Julia Lawall @ 2020-07-21 9:58 UTC (permalink / raw)
To: Markus Elfring
Cc: Michal Marek, Gilles Muller, kernel-janitors, Nicolas Palix,
linux-kernel, Coccinelle
[-- Attachment #1: Type: text/plain, Size: 980 bytes --]
On Tue, 21 Jul 2020, Markus Elfring wrote:
> …
> > +++ b/scripts/coccinelle/api/memdup_user.cocci
> > @@ -39,6 +39,28 @@ …
> …
> > +@depends on patch@
> > +expression from,to,size;
> > +identifier l1,l2;
> > +@@
> > +
> > +- to = \(kvmalloc\|kvzalloc\)(size,\(GFP_KERNEL\|GFP_USER\));
> > ++ to = vmemdup_user(from,size);
>
> I propose to combine the desired adjustment with the previous SmPL rule
> by using another disjunction.
>
>
> > +@rv depends on !patch@
> > +expression from,to,size;
> > +position p;
> > +statement S1,S2;
> > +@@
> > +
> > +* to = \(kvmalloc@p\|kvzalloc@p\)(size,\(GFP_KERNEL\|GFP_USER\));
> > + if (to==NULL || ...) S1
> > + if (copy_from_user(to, from, size) != 0)
> > + S2
>
> * Can it be helpful to omit the SmPL asterisk functionality from
> the operation modes “org” and “report”?
>
> * Should the operation mode “context” work without an extra position metavariable?
This is fine as is in all three aspects.
julia
[-- Attachment #2: Type: text/plain, Size: 136 bytes --]
_______________________________________________
Cocci mailing list
Cocci@systeme.lip6.fr
https://systeme.lip6.fr/mailman/listinfo/cocci
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
@ 2020-07-21 9:58 ` Julia Lawall
0 siblings, 0 replies; 19+ messages in thread
From: Julia Lawall @ 2020-07-21 9:58 UTC (permalink / raw)
To: Markus Elfring
Cc: Michal Marek, Gilles Muller, kernel-janitors, Nicolas Palix,
linux-kernel, Coccinelle
[-- Attachment #1: Type: text/plain, Size: 980 bytes --]
On Tue, 21 Jul 2020, Markus Elfring wrote:
> …
> > +++ b/scripts/coccinelle/api/memdup_user.cocci
> > @@ -39,6 +39,28 @@ …
> …
> > +@depends on patch@
> > +expression from,to,size;
> > +identifier l1,l2;
> > +@@
> > +
> > +- to = \(kvmalloc\|kvzalloc\)(size,\(GFP_KERNEL\|GFP_USER\));
> > ++ to = vmemdup_user(from,size);
>
> I propose to combine the desired adjustment with the previous SmPL rule
> by using another disjunction.
>
>
> > +@rv depends on !patch@
> > +expression from,to,size;
> > +position p;
> > +statement S1,S2;
> > +@@
> > +
> > +* to = \(kvmalloc@p\|kvzalloc@p\)(size,\(GFP_KERNEL\|GFP_USER\));
> > + if (to==NULL || ...) S1
> > + if (copy_from_user(to, from, size) != 0)
> > + S2
>
> * Can it be helpful to omit the SmPL asterisk functionality from
> the operation modes “org” and “report”?
>
> * Should the operation mode “context” work without an extra position metavariable?
This is fine as is in all three aspects.
julia
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
2020-07-21 9:58 ` Julia Lawall
@ 2020-07-21 11:01 ` Markus Elfring
-1 siblings, 0 replies; 19+ messages in thread
From: Markus Elfring @ 2020-07-21 11:01 UTC (permalink / raw)
To: Julia Lawall, Denis Efremov, Coccinelle
Cc: Gilles Muller, Masahiro Yamada, Michal Marek, Nicolas Palix,
linux-kernel, kernel-janitors
> This is fine as is in all three aspects.
I have tried again to point specific data processing consequences out
for operation modes of scripts in the semantic patch language.
Regards,
Markus
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
@ 2020-07-21 11:01 ` Markus Elfring
0 siblings, 0 replies; 19+ messages in thread
From: Markus Elfring @ 2020-07-21 11:01 UTC (permalink / raw)
To: Julia Lawall, Denis Efremov, Coccinelle
Cc: Gilles Muller, Masahiro Yamada, Michal Marek, Nicolas Palix,
linux-kernel, kernel-janitors
> This is fine as is in all three aspects.
I have tried again to point specific data processing consequences out
for operation modes of scripts in the semantic patch language.
Regards,
Markus
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
2020-07-21 9:58 ` Julia Lawall
@ 2020-07-22 5:50 ` Markus Elfring
-1 siblings, 0 replies; 19+ messages in thread
From: Markus Elfring @ 2020-07-22 5:50 UTC (permalink / raw)
To: Julia Lawall, Denis Efremov, Coccinelle
Cc: Gilles Muller, Masahiro Yamada, Michal Marek, Nicolas Palix,
linux-kernel, kernel-janitors
>>> +@depends on patch@
>>> +expression from,to,size;
>>> +identifier l1,l2;
>>> +@@
>>> +
>>> +- to = \(kvmalloc\|kvzalloc\)(size,\(GFP_KERNEL\|GFP_USER\));
>>> ++ to = vmemdup_user(from,size);
>>
>> I propose to combine the desired adjustment with the previous SmPL rule
>> by using another disjunction.
How do you think about to check run time characteristics for
the following SmPL script sketches?
A)
@R1@
@@
// Change something
@R2@
@@
// Change another thing
B)
@Replacement_with_disjunction@
@@
(
// R1: Change something
|
// R2: Change another thing
)
>>> +@rv depends on !patch@
>>> +expression from,to,size;
>>> +position p;
>>> +statement S1,S2;
>>> +@@
>>> +
>>> +* to = \(kvmalloc@p\|kvzalloc@p\)(size,\(GFP_KERNEL\|GFP_USER\));
>>> + if (to==NULL || ...) S1
>>> + if (copy_from_user(to, from, size) != 0)
>>> + S2
>>
>> * Can it be helpful to omit the SmPL asterisk functionality from
>> the operation modes “org” and “report”?
>>
>> * Should the operation mode “context” work without an extra position metavariable?
>
> This is fine as is in all three aspects.
Is every technique from the Coccinelle software required for
each operation mode in such data processing approaches?
Regards,
Markus
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
@ 2020-07-22 5:50 ` Markus Elfring
0 siblings, 0 replies; 19+ messages in thread
From: Markus Elfring @ 2020-07-22 5:50 UTC (permalink / raw)
To: Julia Lawall, Denis Efremov, Coccinelle
Cc: Gilles Muller, Masahiro Yamada, Michal Marek, Nicolas Palix,
linux-kernel, kernel-janitors
>>> +@depends on patch@
>>> +expression from,to,size;
>>> +identifier l1,l2;
>>> +@@
>>> +
>>> +- to = \(kvmalloc\|kvzalloc\)(size,\(GFP_KERNEL\|GFP_USER\));
>>> ++ to = vmemdup_user(from,size);
>>
>> I propose to combine the desired adjustment with the previous SmPL rule
>> by using another disjunction.
How do you think about to check run time characteristics for
the following SmPL script sketches?
A)
@R1@
@@
// Change something
@R2@
@@
// Change another thing
B)
@Replacement_with_disjunction@
@@
(
// R1: Change something
|
// R2: Change another thing
)
>>> +@rv depends on !patch@
>>> +expression from,to,size;
>>> +position p;
>>> +statement S1,S2;
>>> +@@
>>> +
>>> +* to = \(kvmalloc@p\|kvzalloc@p\)(size,\(GFP_KERNEL\|GFP_USER\));
>>> + if (to==NULL || ...) S1
>>> + if (copy_from_user(to, from, size) != 0)
>>> + S2
>>
>> * Can it be helpful to omit the SmPL asterisk functionality from
>> the operation modes “org” and “report”?
>>
>> * Should the operation mode “context” work without an extra position metavariable?
>
> This is fine as is in all three aspects.
Is every technique from the Coccinelle software required for
each operation mode in such data processing approaches?
Regards,
Markus
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
2020-07-22 5:50 ` Markus Elfring
(?)
@ 2020-07-22 6:02 ` Julia Lawall
-1 siblings, 0 replies; 19+ messages in thread
From: Julia Lawall @ 2020-07-22 6:02 UTC (permalink / raw)
To: Markus Elfring
Cc: Denis Efremov, Coccinelle, Gilles Muller, Masahiro Yamada,
Michal Marek, Nicolas Palix, linux-kernel, kernel-janitors
[-- Attachment #1: Type: text/plain, Size: 1496 bytes --]
On Wed, 22 Jul 2020, Markus Elfring wrote:
> >>> +@depends on patch@
> >>> +expression from,to,size;
> >>> +identifier l1,l2;
> >>> +@@
> >>> +
> >>> +- to = \(kvmalloc\|kvzalloc\)(size,\(GFP_KERNEL\|GFP_USER\));
> >>> ++ to = vmemdup_user(from,size);
> >>
> >> I propose to combine the desired adjustment with the previous SmPL rule
> >> by using another disjunction.
>
> How do you think about to check run time characteristics for
> the following SmPL script sketches?
>
> A)
> @R1@
> @@
> // Change something
>
> @R2@
> @@
> // Change another thing
>
>
> B)
> @Replacement_with_disjunction@
> @@
> (
> // R1: Change something
> |
> // R2: Change another thing
> )
Markus, you are welcome to try this since you are concerned about it.
But it doesn't matter.
julia
>
>
> >>> +@rv depends on !patch@
> >>> +expression from,to,size;
> >>> +position p;
> >>> +statement S1,S2;
> >>> +@@
> >>> +
> >>> +* to = \(kvmalloc@p\|kvzalloc@p\)(size,\(GFP_KERNEL\|GFP_USER\));
> >>> + if (to==NULL || ...) S1
> >>> + if (copy_from_user(to, from, size) != 0)
> >>> + S2
> >>
> >> * Can it be helpful to omit the SmPL asterisk functionality from
> >> the operation modes “org” and “report”?
> >>
> >> * Should the operation mode “context” work without an extra position metavariable?
> >
> > This is fine as is in all three aspects.
>
> Is every technique from the Coccinelle software required for
> each operation mode in such data processing approaches?
>
> Regards,
> Markus
>
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [Cocci] [PATCH v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
@ 2020-07-22 6:02 ` Julia Lawall
0 siblings, 0 replies; 19+ messages in thread
From: Julia Lawall @ 2020-07-22 6:02 UTC (permalink / raw)
To: Markus Elfring
Cc: Michal Marek, Gilles Muller, kernel-janitors, Nicolas Palix,
linux-kernel, Coccinelle
[-- Attachment #1: Type: text/plain, Size: 1496 bytes --]
On Wed, 22 Jul 2020, Markus Elfring wrote:
> >>> +@depends on patch@
> >>> +expression from,to,size;
> >>> +identifier l1,l2;
> >>> +@@
> >>> +
> >>> +- to = \(kvmalloc\|kvzalloc\)(size,\(GFP_KERNEL\|GFP_USER\));
> >>> ++ to = vmemdup_user(from,size);
> >>
> >> I propose to combine the desired adjustment with the previous SmPL rule
> >> by using another disjunction.
>
> How do you think about to check run time characteristics for
> the following SmPL script sketches?
>
> A)
> @R1@
> @@
> // Change something
>
> @R2@
> @@
> // Change another thing
>
>
> B)
> @Replacement_with_disjunction@
> @@
> (
> // R1: Change something
> |
> // R2: Change another thing
> )
Markus, you are welcome to try this since you are concerned about it.
But it doesn't matter.
julia
>
>
> >>> +@rv depends on !patch@
> >>> +expression from,to,size;
> >>> +position p;
> >>> +statement S1,S2;
> >>> +@@
> >>> +
> >>> +* to = \(kvmalloc@p\|kvzalloc@p\)(size,\(GFP_KERNEL\|GFP_USER\));
> >>> + if (to==NULL || ...) S1
> >>> + if (copy_from_user(to, from, size) != 0)
> >>> + S2
> >>
> >> * Can it be helpful to omit the SmPL asterisk functionality from
> >> the operation modes “org” and “report”?
> >>
> >> * Should the operation mode “context” work without an extra position metavariable?
> >
> > This is fine as is in all three aspects.
>
> Is every technique from the Coccinelle software required for
> each operation mode in such data processing approaches?
>
> Regards,
> Markus
>
[-- Attachment #2: Type: text/plain, Size: 136 bytes --]
_______________________________________________
Cocci mailing list
Cocci@systeme.lip6.fr
https://systeme.lip6.fr/mailman/listinfo/cocci
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [PATCH v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
@ 2020-07-22 6:02 ` Julia Lawall
0 siblings, 0 replies; 19+ messages in thread
From: Julia Lawall @ 2020-07-22 6:02 UTC (permalink / raw)
To: Markus Elfring
Cc: Michal Marek, Gilles Muller, kernel-janitors, Nicolas Palix,
linux-kernel, Coccinelle
[-- Attachment #1: Type: text/plain, Size: 1496 bytes --]
On Wed, 22 Jul 2020, Markus Elfring wrote:
> >>> +@depends on patch@
> >>> +expression from,to,size;
> >>> +identifier l1,l2;
> >>> +@@
> >>> +
> >>> +- to = \(kvmalloc\|kvzalloc\)(size,\(GFP_KERNEL\|GFP_USER\));
> >>> ++ to = vmemdup_user(from,size);
> >>
> >> I propose to combine the desired adjustment with the previous SmPL rule
> >> by using another disjunction.
>
> How do you think about to check run time characteristics for
> the following SmPL script sketches?
>
> A)
> @R1@
> @@
> // Change something
>
> @R2@
> @@
> // Change another thing
>
>
> B)
> @Replacement_with_disjunction@
> @@
> (
> // R1: Change something
> |
> // R2: Change another thing
> )
Markus, you are welcome to try this since you are concerned about it.
But it doesn't matter.
julia
>
>
> >>> +@rv depends on !patch@
> >>> +expression from,to,size;
> >>> +position p;
> >>> +statement S1,S2;
> >>> +@@
> >>> +
> >>> +* to = \(kvmalloc@p\|kvzalloc@p\)(size,\(GFP_KERNEL\|GFP_USER\));
> >>> + if (to==NULL || ...) S1
> >>> + if (copy_from_user(to, from, size) != 0)
> >>> + S2
> >>
> >> * Can it be helpful to omit the SmPL asterisk functionality from
> >> the operation modes “org” and “report”?
> >>
> >> * Should the operation mode “context” work without an extra position metavariable?
> >
> > This is fine as is in all three aspects.
>
> Is every technique from the Coccinelle software required for
> each operation mode in such data processing approaches?
>
> Regards,
> Markus
>
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
2020-07-22 6:02 ` Julia Lawall
@ 2020-07-22 6:09 ` Markus Elfring
-1 siblings, 0 replies; 19+ messages in thread
From: Markus Elfring @ 2020-07-22 6:09 UTC (permalink / raw)
To: Julia Lawall, Denis Efremov, Coccinelle
Cc: Gilles Muller, Masahiro Yamada, Michal Marek, Nicolas Palix,
linux-kernel, kernel-janitors
> Markus, you are welcome to try this since you are concerned about it.
I dare to point software design variations for some reasons.
> But it doesn't matter.
Under which circumstances would you begin to care more for involved differences
in corresponding run time characteristics?
Regards,
Markus
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
@ 2020-07-22 6:09 ` Markus Elfring
0 siblings, 0 replies; 19+ messages in thread
From: Markus Elfring @ 2020-07-22 6:09 UTC (permalink / raw)
To: Julia Lawall, Denis Efremov, Coccinelle
Cc: Gilles Muller, Masahiro Yamada, Michal Marek, Nicolas Palix,
linux-kernel, kernel-janitors
> Markus, you are welcome to try this since you are concerned about it.
I dare to point software design variations for some reasons.
> But it doesn't matter.
Under which circumstances would you begin to care more for involved differences
in corresponding run time characteristics?
Regards,
Markus
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
2020-07-22 6:09 ` Markus Elfring
(?)
@ 2020-07-22 6:24 ` Julia Lawall
-1 siblings, 0 replies; 19+ messages in thread
From: Julia Lawall @ 2020-07-22 6:24 UTC (permalink / raw)
To: Markus Elfring
Cc: Denis Efremov, Coccinelle, Gilles Muller, Masahiro Yamada,
Michal Marek, Nicolas Palix, linux-kernel, kernel-janitors
On Wed, 22 Jul 2020, Markus Elfring wrote:
> > Markus, you are welcome to try this since you are concerned about it.
>
> I dare to point software design variations for some reasons.
>
>
> > But it doesn't matter.
>
> Under which circumstances would you begin to care more for involved differences
> in corresponding run time characteristics?
When the difference is hours vs seconds. In this case, there are
tradeoffs between the two options, andI don't know which would be faster,
but I think it is extremely unlikely that the difference is noticible.
But if you are concerned about it, you are welcome to try.
julia
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [Cocci] [v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
@ 2020-07-22 6:24 ` Julia Lawall
0 siblings, 0 replies; 19+ messages in thread
From: Julia Lawall @ 2020-07-22 6:24 UTC (permalink / raw)
To: Markus Elfring
Cc: Michal Marek, Gilles Muller, kernel-janitors, Nicolas Palix,
linux-kernel, Coccinelle
On Wed, 22 Jul 2020, Markus Elfring wrote:
> > Markus, you are welcome to try this since you are concerned about it.
>
> I dare to point software design variations for some reasons.
>
>
> > But it doesn't matter.
>
> Under which circumstances would you begin to care more for involved differences
> in corresponding run time characteristics?
When the difference is hours vs seconds. In this case, there are
tradeoffs between the two options, andI don't know which would be faster,
but I think it is extremely unlikely that the difference is noticible.
But if you are concerned about it, you are welcome to try.
julia
_______________________________________________
Cocci mailing list
Cocci@systeme.lip6.fr
https://systeme.lip6.fr/mailman/listinfo/cocci
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
@ 2020-07-22 6:24 ` Julia Lawall
0 siblings, 0 replies; 19+ messages in thread
From: Julia Lawall @ 2020-07-22 6:24 UTC (permalink / raw)
To: Markus Elfring
Cc: Michal Marek, Gilles Muller, kernel-janitors, Nicolas Palix,
linux-kernel, Coccinelle
On Wed, 22 Jul 2020, Markus Elfring wrote:
> > Markus, you are welcome to try this since you are concerned about it.
>
> I dare to point software design variations for some reasons.
>
>
> > But it doesn't matter.
>
> Under which circumstances would you begin to care more for involved differences
> in corresponding run time characteristics?
When the difference is hours vs seconds. In this case, there are
tradeoffs between the two options, andI don't know which would be faster,
but I think it is extremely unlikely that the difference is noticible.
But if you are concerned about it, you are welcome to try.
julia
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
2020-07-22 6:24 ` Julia Lawall
@ 2020-07-22 6:44 ` Markus Elfring
-1 siblings, 0 replies; 19+ messages in thread
From: Markus Elfring @ 2020-07-22 6:44 UTC (permalink / raw)
To: Julia Lawall, Denis Efremov, Coccinelle
Cc: Gilles Muller, Masahiro Yamada, Michal Marek, Nicolas Palix,
linux-kernel, kernel-janitors
>> Under which circumstances would you begin to care more for involved differences
>> in corresponding run time characteristics?
>
> When the difference is hours vs seconds.
Such a view can be influenced by execution environments in considerable ways.
> In this case, there are tradeoffs between the two options,
I am trying to improve the awareness for possible software design variations.
> andI don't know which would be faster,
I am curious if more contributors would get into the mood to compare
data processing approaches a bit more.
> but I think it is extremely unlikely that the difference is noticible.
But the following effects may be known for the evaluation of a SmPL rule
which was combined for two code parts.
* The SmPL dependencies are checked only once.
* Can the source code search efforts be reduced a bit?
> But if you are concerned about it, you are welcome to try.
Will anybody become interested to measure the software behaviour exactly?
Regards,
Markus
^ permalink raw reply [flat|nested] 19+ messages in thread
* Re: [v3 2/3] coccinelle: api: extend memdup_user rule with vmemdup_user()
@ 2020-07-22 6:44 ` Markus Elfring
0 siblings, 0 replies; 19+ messages in thread
From: Markus Elfring @ 2020-07-22 6:44 UTC (permalink / raw)
To: Julia Lawall, Denis Efremov, Coccinelle
Cc: Gilles Muller, Masahiro Yamada, Michal Marek, Nicolas Palix,
linux-kernel, kernel-janitors
>> Under which circumstances would you begin to care more for involved differences
>> in corresponding run time characteristics?
>
> When the difference is hours vs seconds.
Such a view can be influenced by execution environments in considerable ways.
> In this case, there are tradeoffs between the two options,
I am trying to improve the awareness for possible software design variations.
> andI don't know which would be faster,
I am curious if more contributors would get into the mood to compare
data processing approaches a bit more.
> but I think it is extremely unlikely that the difference is noticible.
But the following effects may be known for the evaluation of a SmPL rule
which was combined for two code parts.
* The SmPL dependencies are checked only once.
* Can the source code search efforts be reduced a bit?
> But if you are concerned about it, you are welcome to try.
Will anybody become interested to measure the software behaviour exactly?
Regards,
Markus
^ permalink raw reply [flat|nested] 19+ messages in thread