The official reason is "with the presence of pid namespaces in the

kernel using pid_t-s inside one is no longer safe".
But the reason I fix exactly the infiniband right now is the following.
About a month ago (when the 2.6.25 was not yet released) there still

was a one last caller of a to-be-deprecated-soon function find_pid() -

the kill_proc() function, which in turn was only used by nfs callback

code.
During the last merge window, this last caller was finally eliminated

by some NFS patch(es) and I was about to finally kill this kill_proc()

and find_pid(), but found, that I was late and the kill_proc is now

called from the infiniband driver (commit 58411d1c).
So here's the patch, that turns this code to use struct pid * and (!)

the kill_pid routine. If it is possible to have this one in 2.6.26, I

would appreciate this A LOT and be able to close one more hole in pid

namespaces.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
---
diff --git a/drivers/infiniband/hw/ipath/ipath_driver.c b/drivers/infiniband/hw/ipath/ipath_driver.c

index ce7b7c3..258e66c 100644

--- a/drivers/infiniband/hw/ipath/ipath_driver.c

+++ b/drivers/infiniband/hw/ipath/ipath_driver.c

@@ -2616,7 +2616,7 @@ int ipath_reset_device(int unit)

 				ipath_dbg("unit %u port %d is in use "

 					  "(PID %u cmd %s), can't reset\n",

 					  unit, i,

-					  dd->ipath_pd[i]->port_pid,

+					  pid_nr(dd->ipath_pd[i]->port_pid),

 					  dd->ipath_pd[i]->port_comm);

 				ret = -EBUSY;

 				goto bail;

@@ -2654,19 +2654,21 @@ bail:

 static int ipath_signal_procs(struct ipath_devdata *dd, int sig)

 {

 	int i, sub, any = 0;

-	pid_t pid;

+	struct pid *pid;
 	if (!dd->ipath_pd)

 		return 0;

 	for (i = 1; i < dd->ipath_cfgports; i++) {

-		if (!dd->ipath_pd[i] || !dd->ipath_pd[i]->port_cnt ||

-		    !dd->ipath_pd[i]->port_pid)

+		if (!dd->ipath_pd[i] || !dd->ipath_pd[i]->port_cnt)

 			continue;

 		pid = dd->ipath_pd[i]->port_pid;

+		if (!p...
[ message continues ]

thanks, applied

--

Seems fine to me... ipath guys, any comment?  I think it would be

reasonale to include this with the other ipath fixes when I ask Linus to

pull in a day or two.

--

On Mon, 12 May 2008, Roland Dreier wrote:
| Seems fine to me... ipath guys, any comment?  I think it would be

| reasonale to include this with the other ipath fixes when I ask Linus to

| pull in a day or two.
I looked at the original patch, and it looks fine to me.
Should be fairly easy to cover in ofed 1.4 backport patches for the

older kernels.
Dave Olson

dave.olson@qlogic.com

--