Forcefully resetting a lock

Hi all,

Sometimes a file lock gets stuck. Is there any way on either server or client to obtain a list of locks? Or a list of processes/clients locking a particular file?

And the million dollar question: is it possible to forcefully remove a lock?

I'm using NFSv4 on Linux 2.6.18 (server and client).

Met vriendelijke groet,

Erik Hensema

Signature · 24 lines

HostingXS
eXcellent Service

Telefoon: 024 - 324 91 77
E-mail:   hensema-yolSOB3tinz/[email protected]
Website:  http://www.hostingxs.nl/

-------------------------------------------------------------------------
This SF.net email is sponsored by the 2008 JavaOne(SM) Conference 
Don't miss this year's exciting event. There's still time to save $100. 
Use priority code J8TL2D2. 
http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone
_______________________________________________
NFS maillist  -  [email protected]
https://lists.sourceforge.net/lists/listinfo/nfs
_______________________________________________
Please note that [email protected] is being discontinued.
Please subscribe to [email protected] instead.
    http://vger.kernel.org/vger-lists.html#linux-nfs

--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Hi all,

Sometimes a file lock gets stuck. Is there any way on either server or client to obtain a list of locks? Or a list of processes/clients locking a particular file?
And the million dollar question: is it possible to forcefully remove a lock?

I'm using NFSv4 on Linux 2.6.18 (server and client).

Quoted 8 lines · Erik Hensema / HostingXS Internet Services

Hi all,

Sometimes a file lock gets stuck. Is there any way on either server or client to obtain a list of locks? Or a list of processes/clients locking a particular file?
And the million dollar question: is it possible to forcefully remove a lock?

Quoted 3 lines

I'm using NFSv4 on Linux 2.6.18 (server and client).

*Cough* !

Bruce, so what happens to my lock dropping patch that was said "will get pulled into 2.6.26 kernel" ?

Quoted 10 lines · Wendy Cheng

Quoted 8 lines · Erik Hensema / HostingXS Internet Services

Hi all,

Sometimes a file lock gets stuck. Is there any way on either server or client to obtain a list of locks? Or a list of processes/clients locking a particular file?
And the million dollar question: is it possible to forcefully remove a lock?

Quoted 9 lines

Quoted 4 lines

I'm using NFSv4 on Linux 2.6.18 (server and client).

*Cough* !

Bruce, so what happens to my lock dropping patch that was said "will get pulled into 2.6.26 kernel" ?

Gulp.

I started an alternative implementation, and got it to the point where it was basically working (but I didn't completely trust it). And I did a small fix or two on your patches, but I seem to recall there were one or more todo's there too.

Then I dropped both for a couple weeks.

I'll take a harder look this afternoon....

--b.

Quoted 28 lines · J. Bruce Fields

Quoted 10 lines · Wendy Cheng

Quoted 8 lines · Erik Hensema / HostingXS Internet Services

Hi all,

Sometimes a file lock gets stuck. Is there any way on either server or client to obtain a list of locks? Or a list of processes/clients locking a particular file?
And the million dollar question: is it possible to forcefully remove a lock?

Quoted 8 lines

Quoted 3 lines

I'm using NFSv4 on Linux 2.6.18 (server and client).

*Cough* !

Bruce, so what happens to my lock dropping patch that was said "will get pulled into 2.6.26 kernel" ?

Gulp.

I started an alternative implementation, and got it to the point where it was basically working (but I didn't completely trust it). And I did a small fix or two on your patches, but I seem to recall there were one or more todo's there too.

Quoted 2 lines

Then I dropped both for a couple weeks.

Be carefully. .. "a couple weeks" can turn into "a couple years" .. It has been more than 2 years since my first patch submission. Regardless the patch has been repeatedly requested and had gone thru thorough testings, it just sits there idling while Linux nfs server keeps suffering the very same issue.

Don't get too ambitious. Cluster issues are not trivial - please take one step at a time. The patch is very usable *and* solves an immediate issue *and* has a clean boundary with existing main-line logic. I really don't see the reason to delay it.

Quoted 33 lines · Wendy Cheng

Quoted 31 lines · J. Bruce Fields

Quoted 11 lines · Wendy Cheng

Quoted 8 lines · Erik Hensema / HostingXS Internet Services

Hi all,

Sometimes a file lock gets stuck. Is there any way on either server or client to obtain a list of locks? Or a list of processes/clients locking a particular file?
And the million dollar question: is it possible to forcefully remove a lock?

Quoted 10 lines

Quoted 4 lines

I'm using NFSv4 on Linux 2.6.18 (server and client).

*Cough* !

Bruce, so what happens to my lock dropping patch that was said "will get pulled into 2.6.26 kernel" ?

Gulp.

I started an alternative implementation, and got it to the point where it was basically working (but I didn't completely trust it). And I did a small fix or two on your patches, but I seem to recall there were one or more todo's there too.

Quoted 9 lines

Quoted 3 lines

Then I dropped both for a couple weeks.

Be carefully. .. "a couple weeks" can turn into "a couple years" .. It has been more than 2 years since my first patch submission. Regardless the patch has been repeatedly requested and had gone thru thorough testings, it just sits there idling while Linux nfs server keeps suffering the very same issue.

Yes, apologies for not getting this done on time.

Quoted 5 lines

Don't get too ambitious. Cluster issues are not trivial - please take one step at a time. The patch is very usable *and* solves an immediate issue *and* has a clean boundary with existing main-line logic. I really don't see the reason to delay it.

My current version of your patch follows.

I've rebased it a couple times (the only change I recall being required was a trivial fix to take into account reorganization of struct nameidata.). I also made two other changes; any objections to either?:

Quoted 6 lines · J. Bruce Fields

My current version of your patch follows.

I've rebased it a couple times (the only change I recall being required was a trivial fix to take into account reorganization of struct nameidata.). I also made two other changes; any objections to either?:

Thanks for doing this... The changes look good - though I don't have chances to test it out yet. When is 2.6.26 code cut-off date (or we have missed it again) ?

Really it should be now, though there's another week or so when we can submit stuff if it's in good shape.

But I'm feeling bad about letting this go recently, so I'll look at the last couple issues and do some testing over the next few days...

Please don't pass down the nameidata, but just the super_block. That's all we need in the lower layer functions.

+int nlmsvc_failover_path(struct super_block *sb);

Quoted 1 line · J. Bruce Fields

+int nlmsvc_failover_path(struct super_block *sb);

With a super_block argument the path suffix doesn't make sense anymore. Should probably be an _sb instead.

Quoted 3 lines · Christoph Hellwig

Please don't pass down the nameidata, but just the super_block. That's all we need in the lower layer functions.

Yep, I agree that's nicer; here's the result.

--b.

commit 26a816586b71877d8a84fbb436373099384e328b

Author: Wendy Cheng <[email protected]>
Date:   Thu Jan 17 11:10:12 2008 -0500

lockd: unlock lockd locks held for a certain filesystem

Add /proc/fs/nfsd/unlock_filesystem, which allows e.g.:

shell> echo /mnt/sfs1 > /proc/fs/nfsd/unlock_filesystem

so that a filesystem can be unmounted before allowing a peer nfsd to take over nfs service for the filesystem.

Signed-off-by S. Wendy Cheng <[email protected]>

Cc Lon Hohberger <[email protected]>

Cc Christoph Hellwig <[email protected]>

Signed-off-by J. Bruce Fields <[email protected]>

fs/lockd/svcsubs.c | 66 +++++++++++++++++++++++++++++++++++++++-----
fs/nfsd/nfsctl.c | 65 +++++++++++++++++++++++++++++++++++++++++++
include/linux/lockd/lockd.h | 7 ++++
3 files changed, 131 insertions(+), 7 deletions(-)

fs/lockd/svcsubs.c +34 -5

index e12daba..dcdcff6 100644
@@ -196,6 +196,12 @@ again:
 	return 0;
 }
 
+static int
+nlmsvc_always_match(void *dummy1, struct nlm_host *dummy2)
+{
+	return 1;
+}
+
 /*
  * Inspect a single file
  */

@@ -232,7 +238,8 @@ nlm_file_inuse(struct nlm_file *file)
  * Loop over all files in the file table.
  */
 static int
-nlm_traverse_files(void *data, nlm_host_match_fn_t match)
+nlm_traverse_files(void *data, nlm_host_match_fn_t match,
+		int (*is_failover_file)(void *data, struct nlm_file *file))
 {
 	struct hlist_node *pos, *next;
 	struct nlm_file	*file;

@@ -241,6 +248,8 @@ nlm_traverse_files(void *data, nlm_host_match_fn_t match)
 	mutex_lock(&nlm_file_mutex);
 	for (i = 0; i < FILE_NRHASH; i++) {
 		hlist_for_each_entry_safe(file, pos, next, &nlm_files[i], f_list) {
+			if (is_failover_file && !is_failover_file(data, file))
+				continue;
 			file->f_count++;
 			mutex_unlock(&nlm_file_mutex);
 

@@ -345,7 +354,7 @@ void
 nlmsvc_mark_resources(void)
 {
 	dprintk("lockd: nlmsvc_mark_resources\n");
-	nlm_traverse_files(NULL, nlmsvc_mark_host);
+	nlm_traverse_files(NULL, nlmsvc_mark_host, NULL);
 }
 
 /*

@@ -356,7 +365,7 @@ nlmsvc_free_host_resources(struct nlm_host *host)
 {
 	dprintk("lockd: nlmsvc_free_host_resources\n");
 
-	if (nlm_traverse_files(host, nlmsvc_same_host)) {
+	if (nlm_traverse_files(host, nlmsvc_same_host, NULL)) {
 		printk(KERN_WARNING
 			"lockd: couldn't remove all locks held by %s\n",
 			host->h_name);

@@ -376,8 +385,27 @@ nlmsvc_invalidate_all(void)
 	 * turn, which is about as inefficient as it gets.
 	 * Now we just do it once in nlm_traverse_files.
 	 */
-	nlm_traverse_files(NULL, nlmsvc_is_client);
+	nlm_traverse_files(NULL, nlmsvc_is_client, NULL);
+}
+
+static int
+nlmsvc_failover_file_ok_path(void *datap, struct nlm_file *file)
+{
+	struct super_block *sb = datap;
+
+	return sb == file->f_file->f_path.mnt->mnt_sb;
+}
+
+int
+nlmsvc_failover_path(struct super_block *sb)
+{
+	int ret;
+
+	ret = nlm_traverse_files(sb, nlmsvc_always_match,
+				 nlmsvc_failover_file_ok_path);
+	return ret ? -EIO : 0;
 }
+EXPORT_SYMBOL_GPL(nlmsvc_failover_path);
 
 static int
 nlmsvc_failover_file_ok_ip(void *datap, struct nlm_host *host)

@@ -391,7 +419,8 @@ int
 nlmsvc_failover_ip(__be32 server_addr)
 {
 	int ret;
-	ret = nlm_traverse_files(&server_addr, nlmsvc_failover_file_ok_ip);
+	ret = nlm_traverse_files(&server_addr, nlmsvc_failover_file_ok_ip,
+						NULL);
 	return ret ? -EIO : 0;
 
 }

fs/nfsd/nfsctl.c +32 -0

index 02c3949..b4ca5c9 100644
@@ -55,6 +55,7 @@ enum {
 	NFSD_List,
 	NFSD_Fh,
 	NFSD_FO_UnlockIP,
+	NFSD_FO_UnlockFS,
 	NFSD_Threads,
 	NFSD_Pool_Threads,
 	NFSD_Versions,

@@ -92,6 +93,7 @@ static ssize_t write_recoverydir(struct file *file, char *buf, size_t size);
 #endif
 
 static ssize_t failover_unlock_ip(struct file *file, char *buf, size_t size);
+static ssize_t failover_unlock_fs(struct file *file, char *buf, size_t size);
 
 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
 	[NFSD_Svc] = write_svc,

@@ -103,6 +105,7 @@ static ssize_t (*write_op[])(struct file *, char *, size_t) = {
 	[NFSD_Getfs] = write_getfs,
 	[NFSD_Fh] = write_filehandle,
 	[NFSD_FO_UnlockIP] = failover_unlock_ip,
+	[NFSD_FO_UnlockFS] = failover_unlock_fs,
 	[NFSD_Threads] = write_threads,
 	[NFSD_Pool_Threads] = write_pool_threads,
 	[NFSD_Versions] = write_versions,

@@ -319,6 +322,33 @@ static ssize_t failover_unlock_ip(struct file *file, char *buf, size_t size)
 	return nlmsvc_failover_ip(server_ip);
 }
 
+static ssize_t failover_unlock_fs(struct file *file, char *buf, size_t size)
+{
+	struct nameidata nd;
+	char *fo_path;
+	int error;
+
+	/* sanity check */
+	if (size == 0)
+		return -EINVAL;
+
+	if (buf[size-1] != '\n')
+		return -EINVAL;
+
+	fo_path = buf;
+	if (qword_get(&buf, fo_path, size) < 0)
+		return -EINVAL;
+
+	error = path_lookup(fo_path, 0, &nd);
+	if (error)
+		return error;
+
+	error = nlmsvc_failover_path(nd.path.mnt->mnt_sb);
+
+	path_put(&nd.path);
+	return error;
+}
+
 static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
 {
 	/* request is:

@@ -729,6 +759,8 @@ static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
 		[NFSD_List] = {"exports", &exports_operations, S_IRUGO},
 		[NFSD_FO_UnlockIP] = {"unlock_ip",
 					&transaction_ops, S_IWUSR|S_IRUSR},
+		[NFSD_FO_UnlockFS] = {"unlock_filesystem",
+					&transaction_ops, S_IWUSR|S_IRUSR},
 		[NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR},
 		[NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
 		[NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR},

include/linux/lockd/lockd.h +1 -0

index f06d2db..7cd9c8e 100644
@@ -220,6 +220,7 @@ void		  nlmsvc_invalidate_all(void);
 /*
  * Cluster failover support
  */
+int           nlmsvc_failover_path(struct super_block *sb);
 int           nlmsvc_failover_ip(__be32 server_addr);
 
 static __inline__ struct inode *

#if defined(BRUCE_CHECK_THIS_OUT)
error = nlmsvc_failover_path(nd.path.mnt->mnt_sb); #else
error = nlmsvc_failover_path(nd.mnt->mnt_sb); #endif

-- Wendy

---------- based on the following email ----------------------------

Quoted 199 lines · J. Bruce Fields

Quoted 3 lines · Christoph Hellwig

Please don't pass down the nameidata, but just the super_block. That's all we need in the lower layer functions.

Yep, I agree that's nicer; here's the result.

--b.

commit 26a816586b71877d8a84fbb436373099384e328b

Author: Wendy Cheng <[email protected]>
Date:   Thu Jan 17 11:10:12 2008 -0500

lockd: unlock lockd locks held for a certain filesystem
Add /proc/fs/nfsd/unlock_filesystem, which allows e.g.:
shell> echo /mnt/sfs1 > /proc/fs/nfsd/unlock_filesystem so that a filesystem can be unmounted before allowing a peer
nfsd to
take over nfs service for the filesystem.

Signed-off-by S. Wendy Cheng <[email protected]>

Cc Lon Hohberger <[email protected]>

Cc Christoph Hellwig <[email protected]>

Signed-off-by J. Bruce Fields <[email protected]>

fs/lockd/svcsubs.c | 66
+++++++++++++++++++++++++++++++++++++++-----

     fs/nfsd/nfsctl.c            |   65 +++++++++++++++++++++++++++++++++++++++++++
     include/linux/lockd/lockd.h |    7 ++++
     3 files changed, 131 insertions(+), 7 deletions(-)

fs/lockd/svcsubs.c +9 -1

index e12daba..dcdcff6 100644
@@ -196,6 +196,12 @@ again:
 	return 0;
 }
 +static int
+nlmsvc_always_match(void *dummy1, struct nlm_host *dummy2)
+{
+	return 1;
+}
+
 /*
  * Inspect a single file
  */

@@ -232,7 +238,8 @@ nlm_file_inuse(struct nlm_file *file)
  * Loop over all files in the file table.
  */
 static int
-nlm_traverse_files(void *data, nlm_host_match_fn_t match)
+nlm_traverse_files(void *data, nlm_host_match_fn_t match,
+		int (*is_failover_file)(void *data, struct nlm_file *file))
 {
 	struct hlist_node *pos, *next;
 	struct nlm_file	*file;

@@ -241,6 +248,8 @@ nlm_traverse_files(void *data, nlm_host_match_fn_t match)
 	mutex_lock(&nlm_file_mutex);
 	for (i = 0; i < FILE_NRHASH; i++) {
 		hlist_for_each_entry_safe(file, pos, next, &nlm_files[i], f_list) {
+			if (is_failover_file && !is_failover_file(data, file))
+				continue;
 			file->f_count++;
 			mutex_unlock(&nlm_file_mutex);
 @@ -345,7 +354,7 @@ void

nlmsvc_mark_resources(void)
{

fs/lockd/svcsubs.c +24 -3

 	dprintk("lockd: nlmsvc_mark_resources\n");
-	nlm_traverse_files(NULL, nlmsvc_mark_host);
+	nlm_traverse_files(NULL, nlmsvc_mark_host, NULL);
 }
  /*

@@ -356,7 +365,7 @@ nlmsvc_free_host_resources(struct nlm_host *host)
 {
 	dprintk("lockd: nlmsvc_free_host_resources\n");
 -	if (nlm_traverse_files(host, nlmsvc_same_host)) {
+	if (nlm_traverse_files(host, nlmsvc_same_host, NULL)) {
 		printk(KERN_WARNING
 			"lockd: couldn't remove all locks held by %s\n",
 			host->h_name);

@@ -376,8 +385,27 @@ nlmsvc_invalidate_all(void)
 	 * turn, which is about as inefficient as it gets.
 	 * Now we just do it once in nlm_traverse_files.
 	 */
-	nlm_traverse_files(NULL, nlmsvc_is_client);
+	nlm_traverse_files(NULL, nlmsvc_is_client, NULL);
+}
+
+static int
+nlmsvc_failover_file_ok_path(void *datap, struct nlm_file *file)
+{
+	struct super_block *sb = datap;
+
+	return sb == file->f_file->f_path.mnt->mnt_sb;
+}
+
+int
+nlmsvc_failover_path(struct super_block *sb)
+{
+	int ret;
+
+	ret = nlm_traverse_files(sb, nlmsvc_always_match,
+				 nlmsvc_failover_file_ok_path);
+	return ret ? -EIO : 0;
 }
+EXPORT_SYMBOL_GPL(nlmsvc_failover_path);
  static int
 nlmsvc_failover_file_ok_ip(void *datap, struct nlm_host *host)

@@ -391,7 +419,8 @@ int
 nlmsvc_failover_ip(__be32 server_addr)
 {
 	int ret;
-	ret = nlm_traverse_files(&server_addr, nlmsvc_failover_file_ok_ip);
+	ret = nlm_traverse_files(&server_addr, nlmsvc_failover_file_ok_ip,
+						NULL);
 	return ret ? -EIO : 0;
  }

fs/nfsd/nfsctl.c +31 -0

index 02c3949..b4ca5c9 100644
@@ -55,6 +55,7 @@ enum {
 	NFSD_List,
 	NFSD_Fh,
 	NFSD_FO_UnlockIP,
+	NFSD_FO_UnlockFS,
 	NFSD_Threads,
 	NFSD_Pool_Threads,
 	NFSD_Versions,

@@ -92,6 +93,7 @@ static ssize_t write_recoverydir(struct file *file, char *buf, size_t size);
 #endif
  static ssize_t failover_unlock_ip(struct file *file, char *buf, 
 size_t size);
+static ssize_t failover_unlock_fs(struct file *file, char *buf, size_t size);
  static ssize_t (*write_op[])(struct file *, char *, size_t) = {
 	[NFSD_Svc] = write_svc,

@@ -103,6 +105,7 @@ static ssize_t (*write_op[])(struct file *, char *, size_t) = {
 	[NFSD_Getfs] = write_getfs,
 	[NFSD_Fh] = write_filehandle,
 	[NFSD_FO_UnlockIP] = failover_unlock_ip,
+	[NFSD_FO_UnlockFS] = failover_unlock_fs,
 	[NFSD_Threads] = write_threads,
 	[NFSD_Pool_Threads] = write_pool_threads,
 	[NFSD_Versions] = write_versions,

@@ -319,6 +322,33 @@ static ssize_t failover_unlock_ip(struct file *file, char *buf, size_t size)
 	return nlmsvc_failover_ip(server_ip);
 }
 +static ssize_t failover_unlock_fs(struct file *file, char *buf, 
 size_t size)
+{
+	struct nameidata nd;
+	char *fo_path;
+	int error;
+
+	/* sanity check */
+	if (size == 0)
+		return -EINVAL;
+
+	if (buf[size-1] != '\n')
+		return -EINVAL;
+
+	fo_path = buf;
+	if (qword_get(&buf, fo_path, size) < 0)
+		return -EINVAL;
+
+	error = path_lookup(fo_path, 0, &nd);
+	if (error)
+		return error;
+
+	error = nlmsvc_failover_path(nd.path.mnt->mnt_sb);
+
+	path_put(&nd.path);
+	return error;
+}
+
 static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
 {
 	/* request is:

@@ -729,6 +759,8 @@ static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
 		[NFSD_List] = {"exports", &exports_operations, S_IRUGO},
 		[NFSD_FO_UnlockIP] = {"unlock_ip",
 					&transaction_ops, S_IWUSR|S_IRUSR},
+		[NFSD_FO_UnlockFS] = {"unlock_filesystem",
+					&transaction_ops, S_IWUSR|S_IRUSR},
 		[NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR},
 		[NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
 		[NFSD_Pool_Threads] = {"pool_threads", &transaction_ops, S_IWUSR|S_IRUSR},

include/linux/lockd/lockd.h +1 -0

index f06d2db..7cd9c8e 100644
@@ -220,6 +220,7 @@ void		  nlmsvc_invalidate_all(void);
 /*
  * Cluster failover support
  */
+int           nlmsvc_failover_path(struct super_block *sb);
 int           nlmsvc_failover_ip(__be32 server_addr);
  static __inline__ struct inode *
 

Quoted 6 lines · Wendy Cheng

#if defined(BRUCE_CHECK_THIS_OUT)
error = nlmsvc_failover_path(nd.path.mnt->mnt_sb); #else
error = nlmsvc_failover_path(nd.mnt->mnt_sb); #endif

The vfsmount and dentry got moved into the path argument sometime in the last kernel version or so. Is there a macro defining the latter as a shortcut for the former? I didn't see one.

Quoted 9 lines · J. Bruce Fields

Quoted 6 lines · Wendy Cheng

#if defined(BRUCE_CHECK_THIS_OUT)
error = nlmsvc_failover_path(nd.path.mnt->mnt_sb); #else
error = nlmsvc_failover_path(nd.mnt->mnt_sb); #endif

Quoted 6 lines

The vfsmount and dentry got moved into the path argument sometime in the last kernel version or so. Is there a macro defining the latter as a shortcut for the former? I didn't see one.

Sorry, just realized my kernel is too old (2.6.25)

.. It would be
cumbersome for me to test RHCS with newer kernels. Linux is really a moving target :( ....

Anyway, will think of something else to test this out..

Quoted 12 lines · Wendy Cheng

Quoted 10 lines · J. Bruce Fields

Quoted 7 lines · Wendy Cheng

#if defined(BRUCE_CHECK_THIS_OUT)
error = nlmsvc_failover_path(nd.path.mnt->mnt_sb); #else
error = nlmsvc_failover_path(nd.mnt->mnt_sb); #endif

Quoted 9 lines

Quoted 7 lines

The vfsmount and dentry got moved into the path argument sometime in the last kernel version or so. Is there a macro defining the latter as a shortcut for the former? I didn't see one.

Sorry, just realized my kernel is too old (2.6.25)

2.6.25 is'nt that old quite yet! OK, I get the idea, anyway.

Quoted 4 lines

.. It would be cumbersome for me to test RHCS with newer kernels. Linux is really a moving target :( ....

Anyway, will think of something else to test this out..

OK, thanks. I did some very basic tests, and I'm not terribly worried about it; at worst, it's unlikely to break anything that's already working. But let me know what you find out.

I've sent off my merge request for 2.6.26, but I may try to bundle this up with a few smaller patches I think I've missed and submit another request before the weekend.