From: Julia Lawall <hidden> Date: 2016-09-11 13:30:33
For structure types defined in the same file or local header files, find
top-level static structure declarations that have the following
properties:
1. Never reassigned.
2. Address never taken
3. Not passed to a top-level macro call
4. No pointer or array-typed field passed to a function or stored in a
variable.
Declare structures having all of these properties as const.
Done using Coccinelle.
Based on a suggestion by Joe Perches [off-list ref].
Signed-off-by: Julia Lawall <redacted>
---
The semantic patch seems too long for a commit log, but is in the cover
letter.
drivers/video/fbdev/matrox/matroxfb_g450.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
@@ -433,7 +433,7 @@ static void cve2_init_TVdata(int norm, struct mavenregs* data, const struct outp0x00,/* 3E written multiple times */0x00,/* 3F not written */}};-staticstructmavenregsntscregs={{+staticconststructmavenregsntscregs={{0x21,0xF0,0x7C,0x1F,/* 00: chroma subcarrier */0x00,0x00,/* test */
From: Tomi Valkeinen <hidden> Date: 2016-09-27 08:15:07
On 11/09/16 16:05, Julia Lawall wrote:
For structure types defined in the same file or local header files, find
top-level static structure declarations that have the following
properties:
1. Never reassigned.
2. Address never taken
3. Not passed to a top-level macro call
4. No pointer or array-typed field passed to a function or stored in a
variable.
Declare structures having all of these properties as const.
Done using Coccinelle.
Based on a suggestion by Joe Perches [off-list ref].
Signed-off-by: Julia Lawall <redacted>
---
The semantic patch seems too long for a commit log, but is in the cover
letter.
drivers/video/fbdev/matrox/matroxfb_g450.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
From: Jarkko Sakkinen <hidden> Date: 2016-09-11 17:21:22
On Sun, Sep 11, 2016 at 03:05:42PM +0200, Julia Lawall wrote:
Constify local structures.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
Just my two cents but:
1. You *can* use a static analysis too to find bugs or other issues.
2. However, you should manually do the commits and proper commit
messages to subsystems based on your findings. And I generally think
that if one contributes code one should also at least smoke test changes
somehow.
I don't know if I'm alone with my opinion. I just think that one should
also do the analysis part and not blindly create and submit patches.
Anyway, I'll apply the TPM change at some point. As I said they were
for better. Thanks.
/Jarkko
From: Julia Lawall <hidden> Date: 2016-09-12 08:54:17
On Sun, 11 Sep 2016, Jarkko Sakkinen wrote:
On Sun, Sep 11, 2016 at 03:05:42PM +0200, Julia Lawall wrote:
quoted
Constify local structures.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
Just my two cents but:
1. You *can* use a static analysis too to find bugs or other issues.
2. However, you should manually do the commits and proper commit
messages to subsystems based on your findings. And I generally think
that if one contributes code one should also at least smoke test changes
somehow.
I don't know if I'm alone with my opinion. I just think that one should
also do the analysis part and not blindly create and submit patches.
All of the patches are compile tested. And the individual patches are
submitted to the relevant maintainers. The individual commit messages
give a more detailed explanation of the strategy used to decide that the
structure was constifiable. It seemed redundant to put that in the cover
letter, which will not be committed anyway.
julia
Anyway, I'll apply the TPM change at some point. As I said they were
for better. Thanks.
/Jarkko
From: Jarkko Sakkinen <hidden> Date: 2016-09-12 13:16:43
On Mon, Sep 12, 2016 at 10:54:07AM +0200, Julia Lawall wrote:
On Sun, 11 Sep 2016, Jarkko Sakkinen wrote:
quoted
On Sun, Sep 11, 2016 at 03:05:42PM +0200, Julia Lawall wrote:
quoted
Constify local structures.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
Just my two cents but:
1. You *can* use a static analysis too to find bugs or other issues.
2. However, you should manually do the commits and proper commit
messages to subsystems based on your findings. And I generally think
that if one contributes code one should also at least smoke test changes
somehow.
I don't know if I'm alone with my opinion. I just think that one should
also do the analysis part and not blindly create and submit patches.
All of the patches are compile tested. And the individual patches are
Compile-testing is not testing. If you are not able to test a commit,
you should explain why.
submitted to the relevant maintainers. The individual commit messages
give a more detailed explanation of the strategy used to decide that the
structure was constifiable. It seemed redundant to put that in the cover
letter, which will not be committed anyway.
I don't mean to be harsh but I do not care about your thought process
*that much* when I review a commit (sometimes it might make sense to
explain that but it depends on the context).
I mostly only care why a particular change makes sense for this
particular subsystem. The report given by a static analysis tool can
be a starting point for making a commit but it's not sufficient.
Based on the report you should look subsystems as individuals.
From: Julia Lawall <hidden> Date: 2016-09-12 13:24:08
On Mon, 12 Sep 2016, Jarkko Sakkinen wrote:
On Mon, Sep 12, 2016 at 10:54:07AM +0200, Julia Lawall wrote:
quoted
On Sun, 11 Sep 2016, Jarkko Sakkinen wrote:
quoted
On Sun, Sep 11, 2016 at 03:05:42PM +0200, Julia Lawall wrote:
quoted
Constify local structures.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
Just my two cents but:
1. You *can* use a static analysis too to find bugs or other issues.
2. However, you should manually do the commits and proper commit
messages to subsystems based on your findings. And I generally think
that if one contributes code one should also at least smoke test changes
somehow.
I don't know if I'm alone with my opinion. I just think that one should
also do the analysis part and not blindly create and submit patches.
All of the patches are compile tested. And the individual patches are
Compile-testing is not testing. If you are not able to test a commit,
you should explain why.
quoted
submitted to the relevant maintainers. The individual commit messages
give a more detailed explanation of the strategy used to decide that the
structure was constifiable. It seemed redundant to put that in the cover
letter, which will not be committed anyway.
I don't mean to be harsh but I do not care about your thought process
*that much* when I review a commit (sometimes it might make sense to
explain that but it depends on the context).
I mostly only care why a particular change makes sense for this
particular subsystem. The report given by a static analysis tool can
be a starting point for making a commit but it's not sufficient.
Based on the report you should look subsystems as individuals.
From: Felipe Balbi <hidden> Date: 2016-09-12 13:44:52
Hi,
Jarkko Sakkinen [off-list ref] writes:
On Mon, Sep 12, 2016 at 10:54:07AM +0200, Julia Lawall wrote:
quoted
On Sun, 11 Sep 2016, Jarkko Sakkinen wrote:
quoted
On Sun, Sep 11, 2016 at 03:05:42PM +0200, Julia Lawall wrote:
quoted
Constify local structures.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
Just my two cents but:
1. You *can* use a static analysis too to find bugs or other issues.
2. However, you should manually do the commits and proper commit
messages to subsystems based on your findings. And I generally think
that if one contributes code one should also at least smoke test changes
somehow.
I don't know if I'm alone with my opinion. I just think that one should
also do the analysis part and not blindly create and submit patches.
All of the patches are compile tested. And the individual patches are
Compile-testing is not testing. If you are not able to test a commit,
you should explain why.
Dude, Julia has been doing semantic patching for years already and
nobody has raised any concerns so far. There's already an expectation
that Coccinelle *works* and Julia's sematic patches are sound.
Besides, adding 'const' is something that causes virtually no functional
changes to the point that build-testing is really all you need. Any
problems caused by adding 'const' to a definition will be seen by build
errors or warnings.
Really, just stop with the pointless discussion and go read a bit about
Coccinelle and what semantic patches are giving you. The work done by
Julia and her peers are INRIA have measurable benefits.
You're really making a thunderstorm in a glass of water.
--
balbi
From: Julia Lawall <hidden> Date: 2016-09-12 13:52:22
On Mon, 12 Sep 2016, Felipe Balbi wrote:
Hi,
Jarkko Sakkinen [off-list ref] writes:
quoted
On Mon, Sep 12, 2016 at 10:54:07AM +0200, Julia Lawall wrote:
quoted
On Sun, 11 Sep 2016, Jarkko Sakkinen wrote:
quoted
On Sun, Sep 11, 2016 at 03:05:42PM +0200, Julia Lawall wrote:
quoted
Constify local structures.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
Just my two cents but:
1. You *can* use a static analysis too to find bugs or other issues.
2. However, you should manually do the commits and proper commit
messages to subsystems based on your findings. And I generally think
that if one contributes code one should also at least smoke test changes
somehow.
I don't know if I'm alone with my opinion. I just think that one should
also do the analysis part and not blindly create and submit patches.
All of the patches are compile tested. And the individual patches are
Compile-testing is not testing. If you are not able to test a commit,
you should explain why.
Dude, Julia has been doing semantic patching for years already and
nobody has raised any concerns so far. There's already an expectation
that Coccinelle *works* and Julia's sematic patches are sound.
Besides, adding 'const' is something that causes virtually no functional
changes to the point that build-testing is really all you need. Any
problems caused by adding 'const' to a definition will be seen by build
errors or warnings.
Really, just stop with the pointless discussion and go read a bit about
Coccinelle and what semantic patches are giving you. The work done by
Julia and her peers are INRIA have measurable benefits.
You're really making a thunderstorm in a glass of water.
Thanks for the defense, but since a lot of these patches torned out to be
wrong, due to an incorrect parse by Coccinelle, combined with an
unpleasantly lax compiler, Jarkko does have a point that I should have
looked at the patches more carefully. In any case, I have written to the
maintainers relevant to the patches that turned out to be incorrect.
julia
From: Jarkko Sakkinen <hidden> Date: 2016-09-12 18:50:34
On Mon, Sep 12, 2016 at 03:52:08PM +0200, Julia Lawall wrote:
On Mon, 12 Sep 2016, Felipe Balbi wrote:
quoted
Hi,
Jarkko Sakkinen [off-list ref] writes:
quoted
On Mon, Sep 12, 2016 at 10:54:07AM +0200, Julia Lawall wrote:
quoted
On Sun, 11 Sep 2016, Jarkko Sakkinen wrote:
quoted
On Sun, Sep 11, 2016 at 03:05:42PM +0200, Julia Lawall wrote:
quoted
Constify local structures.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
Just my two cents but:
1. You *can* use a static analysis too to find bugs or other issues.
2. However, you should manually do the commits and proper commit
messages to subsystems based on your findings. And I generally think
that if one contributes code one should also at least smoke test changes
somehow.
I don't know if I'm alone with my opinion. I just think that one should
also do the analysis part and not blindly create and submit patches.
All of the patches are compile tested. And the individual patches are
Compile-testing is not testing. If you are not able to test a commit,
you should explain why.
Dude, Julia has been doing semantic patching for years already and
nobody has raised any concerns so far. There's already an expectation
that Coccinelle *works* and Julia's sematic patches are sound.
Besides, adding 'const' is something that causes virtually no functional
changes to the point that build-testing is really all you need. Any
problems caused by adding 'const' to a definition will be seen by build
errors or warnings.
Really, just stop with the pointless discussion and go read a bit about
Coccinelle and what semantic patches are giving you. The work done by
Julia and her peers are INRIA have measurable benefits.
You're really making a thunderstorm in a glass of water.
Thanks for the defense, but since a lot of these patches torned out to be
wrong, due to an incorrect parse by Coccinelle, combined with an
unpleasantly lax compiler, Jarkko does have a point that I should have
looked at the patches more carefully. In any case, I have written to the
maintainers relevant to the patches that turned out to be incorrect.
Exactly. I'm not excepting that every commit would require extensive
analysis but it would be good to quickly at least skim through commits
and see if they make sense (or ask if unsure) :)
And I'm fine with compile testing if it is mentioned in the commit msg.
On Mon, Sep 12, 2016 at 3:43 PM, Felipe Balbi
[off-list ref] wrote:
Jarkko Sakkinen [off-list ref] writes:
quoted
On Mon, Sep 12, 2016 at 10:54:07AM +0200, Julia Lawall wrote:
quoted
On Sun, 11 Sep 2016, Jarkko Sakkinen wrote:
quoted
On Sun, Sep 11, 2016 at 03:05:42PM +0200, Julia Lawall wrote:
quoted
Constify local structures.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
Just my two cents but:
1. You *can* use a static analysis too to find bugs or other issues.
2. However, you should manually do the commits and proper commit
messages to subsystems based on your findings. And I generally think
that if one contributes code one should also at least smoke test changes
somehow.
I don't know if I'm alone with my opinion. I just think that one should
also do the analysis part and not blindly create and submit patches.
All of the patches are compile tested. And the individual patches are
Compile-testing is not testing. If you are not able to test a commit,
you should explain why.
Dude, Julia has been doing semantic patching for years already and
nobody has raised any concerns so far. There's already an expectation
that Coccinelle *works* and Julia's sematic patches are sound.
+1
Besides, adding 'const' is something that causes virtually no functional
changes to the point that build-testing is really all you need. Any
problems caused by adding 'const' to a definition will be seen by build
errors or warnings.
Unfortunately in this particular case they could lead to failures that can only
be detected at runtime, when failing o write to a read-only piece of memory,
due to the casting away of the constness of the pointers later.
Fortunately this was detected during code review (doh...).
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
From: Jarkko Sakkinen <hidden> Date: 2016-09-12 20:15:01
On Mon, Sep 12, 2016 at 04:43:58PM +0300, Felipe Balbi wrote:
Hi,
Jarkko Sakkinen [off-list ref] writes:
quoted
On Mon, Sep 12, 2016 at 10:54:07AM +0200, Julia Lawall wrote:
quoted
On Sun, 11 Sep 2016, Jarkko Sakkinen wrote:
quoted
On Sun, Sep 11, 2016 at 03:05:42PM +0200, Julia Lawall wrote:
quoted
Constify local structures.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
Just my two cents but:
1. You *can* use a static analysis too to find bugs or other issues.
2. However, you should manually do the commits and proper commit
messages to subsystems based on your findings. And I generally think
that if one contributes code one should also at least smoke test changes
somehow.
I don't know if I'm alone with my opinion. I just think that one should
also do the analysis part and not blindly create and submit patches.
All of the patches are compile tested. And the individual patches are
Compile-testing is not testing. If you are not able to test a commit,
you should explain why.
Dude, Julia has been doing semantic patching for years already and
nobody has raised any concerns so far. There's already an expectation
that Coccinelle *works* and Julia's sematic patches are sound.
Besides, adding 'const' is something that causes virtually no functional
changes to the point that build-testing is really all you need. Any
problems caused by adding 'const' to a definition will be seen by build
errors or warnings.
Really, just stop with the pointless discussion and go read a bit about
Coccinelle and what semantic patches are giving you. The work done by
Julia and her peers are INRIA have measurable benefits.
You're really making a thunderstorm in a glass of water.
Hmm... I've been using coccinelle in cyclic basis for some time now.
My comment was oversized but I didn't mean it to be impolite or attack
of any kind for that matter.
From: Julia Lawall <hidden> Date: 2016-09-12 21:12:01
On Mon, 12 Sep 2016, Jarkko Sakkinen wrote:
On Mon, Sep 12, 2016 at 04:43:58PM +0300, Felipe Balbi wrote:
quoted
Hi,
Jarkko Sakkinen [off-list ref] writes:
quoted
On Mon, Sep 12, 2016 at 10:54:07AM +0200, Julia Lawall wrote:
quoted
On Sun, 11 Sep 2016, Jarkko Sakkinen wrote:
quoted
On Sun, Sep 11, 2016 at 03:05:42PM +0200, Julia Lawall wrote:
quoted
Constify local structures.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
Just my two cents but:
1. You *can* use a static analysis too to find bugs or other issues.
2. However, you should manually do the commits and proper commit
messages to subsystems based on your findings. And I generally think
that if one contributes code one should also at least smoke test changes
somehow.
I don't know if I'm alone with my opinion. I just think that one should
also do the analysis part and not blindly create and submit patches.
All of the patches are compile tested. And the individual patches are
Compile-testing is not testing. If you are not able to test a commit,
you should explain why.
Dude, Julia has been doing semantic patching for years already and
nobody has raised any concerns so far. There's already an expectation
that Coccinelle *works* and Julia's sematic patches are sound.
Besides, adding 'const' is something that causes virtually no functional
changes to the point that build-testing is really all you need. Any
problems caused by adding 'const' to a definition will be seen by build
errors or warnings.
Really, just stop with the pointless discussion and go read a bit about
Coccinelle and what semantic patches are giving you. The work done by
Julia and her peers are INRIA have measurable benefits.
You're really making a thunderstorm in a glass of water.
Hmm... I've been using coccinelle in cyclic basis for some time now.
My comment was oversized but I didn't mean it to be impolite or attack
of any kind for that matter.
From: Joe Perches <joe@perches.com> Date: 2016-09-11 17:56:36
On Sun, 2016-09-11 at 15:05 +0200, Julia Lawall wrote:
Constify local structures.
Thanks Julia.
A few suggestions & questions:
Perhaps the script should go into scripts/coccinelle/
so that future cases could be caught by the robot
and commit message referenced by the patch instances.
Can you please compile the files modified using the
appropriate defconfig/allyesconfig and show the
movement from data to const by using
$ size <object>.new/old
and include that in the changelogs (maybe next time)?
Is it possible for a rule to trace the instances where
an address of a struct or struct member is taken by
locally defined and declared function call where the
callee does not modify any dereferenced object?
ie:
struct foo {
int bar;
char *baz;
};
struct foo qux[] = {
{ 1, "description 1" },
{ 2, "dewcription 2" },
[ n, "etc" ]...,
};
void message(struct foo *msg)
{
printk("%d %s\n", msg->bar, msg->baz);
}
where some code uses
message(qux[index]);
So could a coccinelle script change:
struct foo qux[] = { to const struct foo quz[] = {
and
void message(struct foo *msg) to void message(const struct foo *msg)
From: Julia Lawall <hidden> Date: 2016-09-11 19:11:46
On Sun, 11 Sep 2016, Joe Perches wrote:
On Sun, 2016-09-11 at 15:05 +0200, Julia Lawall wrote:
quoted
Constify local structures.
Thanks Julia.
A few suggestions & questions:
Perhaps the script should go into scripts/coccinelle/
so that future cases could be caught by the robot
and commit message referenced by the patch instances.
OK.
Can you please compile the files modified using the
appropriate defconfig/allyesconfig and show the
I currently send patches for this issue only for files that compile using
the x86 allyesconfig.
movement from data to const by using
$ size <object>.new/old
and include that in the changelogs (maybe next time)?
OK, thanks for the suggestion.
Is it possible for a rule to trace the instances where
an address of a struct or struct member is taken by
locally defined and declared function call where the
callee does not modify any dereferenced object?
ie:
struct foo {
int bar;
char *baz;
};
struct foo qux[] = {
{ 1, "description 1" },
{ 2, "dewcription 2" },
[ n, "etc" ]...,
};
void message(struct foo *msg)
{
printk("%d %s\n", msg->bar, msg->baz);
}
where some code uses
message(qux[index]);
So could a coccinelle script change:
struct foo qux[] = { to const struct foo quz[] = {
and
void message(struct foo *msg) to void message(const struct foo *msg)
Yes, this could be possible too.
Thanks for the feedback.
julia