[PATCH v2 0/2] sctp: Consolidate and ratelimit deprecation warnings

[PATCH v2 0/2] sctp: Consolidate and ratelimit deprecation warnings

[Neil Horman]

The SCTP protocol has several deprecation warnings in its setsockopt path that
can be triggered by unprivlidged users.  Since these are not ratelimited, we can
spam the logs quite easily here.  Since these are all deprecation warnings, and
that type of warning isn't uncommon in the rest of the kernel, lets make a
common pr_warn_deprecated macro to produce somewhat generalized ratelimited
deprecation warnings easily

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: David Miller <davem@davemloft.net>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: netdev@vger.kernel.org
CC: linux-kernel@vger.kernel.org

[PATCH v2 1/2] printk: Add a pr_warn_deprecated macro

[Neil Horman]

sctp has several points in its setsockopt path in which it issues deprecation
warnings.  It seems like it might be handy to macrotize such a warning so other
subsystems can use it easily

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: "David S. Miller" <davem@davemloft.net>
CC: linux-kernel@vger.kernel.org
---
 include/linux/printk.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/include/linux/printk.h b/include/linux/printk.h
index 6949258..2e043b3 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -336,6 +336,9 @@ extern asmlinkage void dump_stack(void) __cold;
 	printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 /* no pr_cont_ratelimited, don't do that... */
 
+#define pr_warn_deprecated(fmt, ...)					\
+	pr_warn_ratelimited("Deprecated: " fmt, ##__VA_ARGS__)
+
 #if defined(DEBUG)
 #define pr_devel_ratelimited(fmt, ...)					\
 	printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
-- 
1.8.3.1

Re: [PATCH v2 1/2] printk: Add a pr_warn_deprecated macro

[Joe Perches]

(adding Andrew Morton to cc's)

On Mon, 2013-12-16 at 12:06 -0500, Neil Horman wrote:
> sctp has several points in its setsockopt path in which it issues deprecation
> warnings.  It seems like it might be handy to macrotize such a warning so other
> subsystems can use it easily
[]
> diff --git a/include/linux/printk.h b/include/linux/printk.h
[]
> @@ -336,6 +336,9 @@ extern asmlinkage void dump_stack(void) __cold;
>  	printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
>  /* no pr_cont_ratelimited, don't do that... */
>  
> +#define pr_warn_deprecated(fmt, ...)					\
> +	pr_warn_ratelimited("Deprecated: " fmt, ##__VA_ARGS__)

Continuing the thread from:
http://patchwork.ozlabs.org/patch/301738/

Making this a global kernel #define is different than
using it in your subsystem.

I think this is very analogous to the FW_INFO/FW_WARN
uses and maybe should just have a #define for the
string "deprecated:" inserted as a constant.

ie: just using

	pr_warn_once(DEPRECATED fmt, args...)
or
	pr_warn_ratelimited(DEPRECATED fmt, args...)

Re: [PATCH v2 1/2] printk: Add a pr_warn_deprecated macro

[Neil Horman]

On Mon, Dec 16, 2013 at 09:50:01AM -0800, Joe Perches wrote:
> (adding Andrew Morton to cc's)
> 
> On Mon, 2013-12-16 at 12:06 -0500, Neil Horman wrote:
> > sctp has several points in its setsockopt path in which it issues deprecation
> > warnings.  It seems like it might be handy to macrotize such a warning so other
> > subsystems can use it easily
> []
> > diff --git a/include/linux/printk.h b/include/linux/printk.h
> []
> > @@ -336,6 +336,9 @@ extern asmlinkage void dump_stack(void) __cold;
> >  	printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
> >  /* no pr_cont_ratelimited, don't do that... */
> >  
> > +#define pr_warn_deprecated(fmt, ...)					\
> > +	pr_warn_ratelimited("Deprecated: " fmt, ##__VA_ARGS__)
> 
> Continuing the thread from:
> http://patchwork.ozlabs.org/patch/301738/
> 
> Making this a global kernel #define is different than
> using it in your subsystem.
> 
> I think this is very analogous to the FW_INFO/FW_WARN
> uses and maybe should just have a #define for the
> string "deprecated:" inserted as a constant.
> 
> ie: just using
> 
> 	pr_warn_once(DEPRECATED fmt, args...)
> or
> 	pr_warn_ratelimited(DEPRECATED fmt, args...)
> 
The define is a nice idea, but I'm not sure about the use of the once variant.
Multiple users may use multiple programs that trigger these deprecation
warnings, and we should probably warn on each of them to avoid masking the
others.

I'll work up a new patch set
Neil

> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-sctp" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 

[PATCH v3 0/2] sctp: Consolidate and ratelimit deprecation warnings

[Neil Horman]

The SCTP protocol has several deprecation warnings in its setsockopt path that
can be triggered by unprivlidged users.  Since these are not ratelimited, we can
spam the logs quite easily here.  Since these are all deprecation warnings, and
that type of warning isn't uncommon in the rest of the kernel, lets make a
common pr_warn_deprecated macro to produce somewhat generalized ratelimited
deprecation warnings easily

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: David Miller <davem@davemloft.net>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: netdev@vger.kernel.org
CC: linux-kernel@vger.kernel.org

---
Change notes

v2) Converted to use a pr_warn_deprecated macro
v3) Converted to use a DEPRECATED macro with regular pr_* macros

[PATCH v3 1/2] printk: Add a DEPRECATED macro

[Neil Horman]

sctp has several points in its setsockopt path in which it issues deprecation
warnings.  It seems like it might be handy to macrotize such a warning so other
subsystems can use it easily

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: "David S. Miller" <davem@davemloft.net>
CC: linux-kernel@vger.kernel.org

---
Change Notes:

v3)
* Convert to using a string prefix rather than a specific pr_ macro
---
 include/linux/printk.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/linux/printk.h b/include/linux/printk.h
index 6949258..26fb95c 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -88,6 +88,13 @@ struct va_format {
 #define HW_ERR		"[Hardware Error]: "
 
 /*
+ * DEPRECATED
+ * Add this to a message whenever you want to warn user space about the use
+ * of a deprecated aspect of an API so they can stop using it
+ */
+#define DEPRECATED	"[Deprecated]: "
+
+/*
  * Dummy printk for disabled debugging statements to use whilst maintaining
  * gcc's format and side-effect checking.
  */
-- 
1.8.3.1

Re: [PATCH v3 0/2] sctp: Consolidate and ratelimit deprecation warnings

[David Miller]

From: Neil Horman <nhorman@tuxdriver.com>
Date: Tue, 17 Dec 2013 11:19:57 -0500

> The SCTP protocol has several deprecation warnings in its setsockopt path that
> can be triggered by unprivlidged users.  Since these are not ratelimited, we can
> spam the logs quite easily here.  Since these are all deprecation warnings, and
> that type of warning isn't uncommon in the rest of the kernel, lets make a
> common pr_warn_deprecated macro to produce somewhat generalized ratelimited
> deprecation warnings easily
> 
> Signed-off-by: Neil Horman <nhorman@tuxdriver.com>

Neil, I really wish you would CC: netdev on all of the patches in the
series.  Otherwise only some of them end up in patchwork, and this makes
a lot more work for me if I want to actually apply this, which I do.

Please resubmit this properly, thanks.

Re: [PATCH v3 0/2] sctp: Consolidate and ratelimit deprecation warnings

[Neil Horman]

On Sun, Dec 22, 2013 at 05:56:59PM -0500, David Miller wrote:
> From: Neil Horman <nhorman@tuxdriver.com>
> Date: Tue, 17 Dec 2013 11:19:57 -0500
> 
> > The SCTP protocol has several deprecation warnings in its setsockopt path that
> > can be triggered by unprivlidged users.  Since these are not ratelimited, we can
> > spam the logs quite easily here.  Since these are all deprecation warnings, and
> > that type of warning isn't uncommon in the rest of the kernel, lets make a
> > common pr_warn_deprecated macro to produce somewhat generalized ratelimited
> > deprecation warnings easily
> > 
> > Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
> 
> Neil, I really wish you would CC: netdev on all of the patches in the
> series.  Otherwise only some of them end up in patchwork, and this makes
> a lot more work for me if I want to actually apply this, which I do.
> 
> Please resubmit this properly, thanks.
> 

Will do, thanks.
Neil

[PATCH v4 0/2] sctp: Consolidate and ratelimit deprecation warnings

[Neil Horman]

The SCTP protocol has several deprecation warnings in its setsockopt path that
can be triggered by unprivlidged users.  Since these are not ratelimited, we can
spam the logs quite easily here.  Since these are all deprecation warnings, and
that type of warning isn't uncommon in the rest of the kernel, lets make a
common pr_warn_deprecated macro to produce somewhat generalized ratelimited
deprecation warnings easily

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: David Miller <davem@davemloft.net>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: netdev@vger.kernel.org
CC: linux-kernel@vger.kernel.org

---
Change notes

v2) Converted to use a pr_warn_deprecated macro
v3) Converted to use a DEPRECATED macro with regular pr_* macros
v4) CC netdev on all patches as per DaveM

[PATCH v4 1/2] printk: Add a DEPRECATED macro

[Neil Horman]

sctp has several points in its setsockopt path in which it issues deprecation
warnings.  It seems like it might be handy to macrotize such a warning so other
subsystems can use it easily

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC: "David S. Miller" <davem@davemloft.net>
CC: linux-kernel@vger.kernel.org
CC: netdev@vger.kernel.org

---
Change Notes:

v3)
* Convert to using a string prefix rather than a specific pr_ macro
---
 include/linux/printk.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/linux/printk.h b/include/linux/printk.h
index 6949258..26fb95c 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -88,6 +88,13 @@ struct va_format {
 #define HW_ERR		"[Hardware Error]: "
 
 /*
+ * DEPRECATED
+ * Add this to a message whenever you want to warn user space about the use
+ * of a deprecated aspect of an API so they can stop using it
+ */
+#define DEPRECATED	"[Deprecated]: "
+
+/*
  * Dummy printk for disabled debugging statements to use whilst maintaining
  * gcc's format and side-effect checking.
  */
-- 
1.8.3.1

Re: [PATCH v4 0/2] sctp: Consolidate and ratelimit deprecation warnings

[Ben Hutchings]

On Mon, 2013-12-23 at 08:29 -0500, Neil Horman wrote:
> The SCTP protocol has several deprecation warnings in its setsockopt path that
> can be triggered by unprivlidged users.  Since these are not ratelimited, we can
> spam the logs quite easily here.  Since these are all deprecation warnings, and
> that type of warning isn't uncommon in the rest of the kernel, lets make a
> common pr_warn_deprecated macro to produce somewhat generalized ratelimited
> deprecation warnings easily
[...]

No objection to these changes, but I think deprecation warnings should
log at least the command name and maybe also the pid of the caller.

Ben.

-- 
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.

Re: [PATCH v4 0/2] sctp: Consolidate and ratelimit deprecation warnings

[Neil Horman]

On Mon, Dec 23, 2013 at 10:55:16PM +0000, Ben Hutchings wrote:
> On Mon, 2013-12-23 at 08:29 -0500, Neil Horman wrote:
> > The SCTP protocol has several deprecation warnings in its setsockopt path that
> > can be triggered by unprivlidged users.  Since these are not ratelimited, we can
> > spam the logs quite easily here.  Since these are all deprecation warnings, and
> > that type of warning isn't uncommon in the rest of the kernel, lets make a
> > common pr_warn_deprecated macro to produce somewhat generalized ratelimited
> > deprecation warnings easily
> [...]
> 
> No objection to these changes, but I think deprecation warnings should
> log at least the command name and maybe also the pid of the caller.
> 
I didn't change the contents of the strings in this patch, I just wanted to
avoid log spamming, but I think adding caller pid/name is a good idea.  I'll do
that in a followon patch after the holidays
Neil

> Ben.
> 
> -- 
> Ben Hutchings, Staff Engineer, Solarflare
> Not speaking for my employer; that's the marketing department's job.
> They asked us to note that Solarflare product names are trademarked.
> 
> 

Re: [PATCH v4 0/2] sctp: Consolidate and ratelimit deprecation warnings

[David Miller]

From: Neil Horman <nhorman@tuxdriver.com>
Date: Mon, 23 Dec 2013 08:29:41 -0500

> The SCTP protocol has several deprecation warnings in its setsockopt path that
> can be triggered by unprivlidged users.  Since these are not ratelimited, we can
> spam the logs quite easily here.  Since these are all deprecation warnings, and
> that type of warning isn't uncommon in the rest of the kernel, lets make a
> common pr_warn_deprecated macro to produce somewhat generalized ratelimited
> deprecation warnings easily
> 
> Signed-off-by: Neil Horman <nhorman@tuxdriver.com>

Series applied, thanks Neil.

Please consider Ben's suggestion to provide the offending command string
in the log output.

Re: [PATCH v4 0/2] sctp: Consolidate and ratelimit deprecation warnings

[Joe Perches]

On Tue, 2013-12-31 at 14:00 -0500, David Miller wrote:
> From: Neil Horman <nhorman@tuxdriver.com>
> Date: Mon, 23 Dec 2013 08:29:41 -0500
> 
> > The SCTP protocol has several deprecation warnings in its setsockopt path that
> > can be triggered by unprivlidged users.  Since these are not ratelimited, we can
> > spam the logs quite easily here.  Since these are all deprecation warnings, and
> > that type of warning isn't uncommon in the rest of the kernel, lets make a
> > common pr_warn_deprecated macro to produce somewhat generalized ratelimited
> > deprecation warnings easily
> > 
> > Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
> 
> Series applied, thanks Neil.
> 
> Please consider Ben's suggestion to provide the offending command string
> in the log output.

If something like the printk extension described in this thread
http://thread.gmane.org/gmane.linux.kernel/1620126 is ever accepted,
then it should be pretty easy to add later.

Re: [PATCH v4 0/2] sctp: Consolidate and ratelimit deprecation warnings

[Neil Horman]

On Tue, Dec 31, 2013 at 02:00:00PM -0500, David Miller wrote:
> From: Neil Horman <nhorman@tuxdriver.com>
> Date: Mon, 23 Dec 2013 08:29:41 -0500
> 
> > The SCTP protocol has several deprecation warnings in its setsockopt path that
> > can be triggered by unprivlidged users.  Since these are not ratelimited, we can
> > spam the logs quite easily here.  Since these are all deprecation warnings, and
> > that type of warning isn't uncommon in the rest of the kernel, lets make a
> > common pr_warn_deprecated macro to produce somewhat generalized ratelimited
> > deprecation warnings easily
> > 
> > Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
> 
> Series applied, thanks Neil.
> 
> Please consider Ben's suggestion to provide the offending command string
> in the log output.
> 
Of course, I'll take care of it this week after I dig through all the holiday
email.
Neil