* [PATCH rdma-rc] RDMA/restrack: don't use uaccess_kernel()
@ 2018-02-08 20:09 Steve Wise
[not found] ` <eac01039be8c0518e37928e5b003a911c32e53a7.1518468700.git.swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
0 siblings, 1 reply; 7+ messages in thread
From: Steve Wise @ 2018-02-08 20:09 UTC (permalink / raw)
To: jgg-VPRAkNaXOzVWk0Htik3J/w, dledford-H+wXaHxf7aLQT0dZR+AlfA
Cc: leon-DgEjT+Ai2ygdnm+yROfE0A, linux-rdma-u79uwXL29TY76Z2rM5mHXA
uaccess_kernel() isn't sufficient to determine if an rdma resource is
user-mode or not. For example, resources allocated in the add_one()
function of an ib_client get falsely labeled as user mode, when they
are kernel mode allocations. EG: mad qps.
The result is that these qps are skipped over during a nldev query
because of an erroneous namespace mismatch.
So now we determine if the resource is user-mode by looking at the object
struct's uobject or similar pointer to know if it was allocated for user
mode applications.
Fixes: 02d8883f520e ("RDMA/restrack: Add general infrastructure to track RDMA resources")
Signed-off-by: Steve Wise <swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
---
drivers/infiniband/core/restrack.c | 36 ++++++++++++++++++++++++++++++++++--
1 file changed, 34 insertions(+), 2 deletions(-)
diff --git a/drivers/infiniband/core/restrack.c b/drivers/infiniband/core/restrack.c
index 857637b..83bce7e 100644
--- a/drivers/infiniband/core/restrack.c
+++ b/drivers/infiniband/core/restrack.c
@@ -7,7 +7,6 @@
#include <rdma/restrack.h>
#include <linux/mutex.h>
#include <linux/sched/task.h>
-#include <linux/uaccess.h>
#include <linux/pid_namespace.h>
void rdma_restrack_init(struct rdma_restrack_root *res)
@@ -93,6 +92,39 @@ static struct ib_device *res_to_dev(struct rdma_restrack_entry *res)
return dev;
}
+static bool res_is_user(struct rdma_restrack_entry *res)
+{
+ enum rdma_restrack_type type = res->type;
+ struct ib_xrcd *xrcd;
+ struct ib_pd *pd;
+ struct ib_cq *cq;
+ struct ib_qp *qp;
+ bool is_user = false;
+
+ switch (type) {
+ case RDMA_RESTRACK_PD:
+ pd = container_of(res, struct ib_pd, res);
+ is_user = pd->uobject;
+ break;
+ case RDMA_RESTRACK_CQ:
+ cq = container_of(res, struct ib_cq, res);
+ is_user = cq->uobject;
+ break;
+ case RDMA_RESTRACK_QP:
+ qp = container_of(res, struct ib_qp, res);
+ if (qp->pd)
+ is_user = qp->pd->uobject;
+ break;
+ case RDMA_RESTRACK_XRCD:
+ xrcd = container_of(res, struct ib_xrcd, res);
+ is_user = xrcd->inode;
+ break;
+ default:
+ WARN_ONCE(true, "Wrong resource tracking type %u\n", type);
+ }
+ return is_user;
+}
+
void rdma_restrack_add(struct rdma_restrack_entry *res)
{
struct ib_device *dev = res_to_dev(res);
@@ -100,7 +132,7 @@ void rdma_restrack_add(struct rdma_restrack_entry *res)
if (!dev)
return;
- if (!uaccess_kernel()) {
+ if (res_is_user(res)) {
get_task_struct(current);
res->task = current;
res->kern_name = NULL;
--
1.8.3.1
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH rdma-rc] RDMA/restrack: don't use uaccess_kernel()
[not found] ` <eac01039be8c0518e37928e5b003a911c32e53a7.1518468700.git.swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
@ 2018-02-13 9:01 ` Leon Romanovsky
[not found] ` <20180213090122.GT2197-U/DQcQFIOTAAJjI8aNfphQ@public.gmane.org>
2018-02-15 21:58 ` Jason Gunthorpe
1 sibling, 1 reply; 7+ messages in thread
From: Leon Romanovsky @ 2018-02-13 9:01 UTC (permalink / raw)
To: Steve Wise
Cc: jgg-VPRAkNaXOzVWk0Htik3J/w, dledford-H+wXaHxf7aLQT0dZR+AlfA,
linux-rdma-u79uwXL29TY76Z2rM5mHXA
[-- Attachment #1: Type: text/plain, Size: 681 bytes --]
On Thu, Feb 08, 2018 at 12:09:43PM -0800, Steve Wise wrote:
> uaccess_kernel() isn't sufficient to determine if an rdma resource is
> user-mode or not. For example, resources allocated in the add_one()
> function of an ib_client get falsely labeled as user mode, when they
> are kernel mode allocations. EG: mad qps.
I found the reason.
It is due to the difference between code compiled as
a module (=m) or compiled in as monolith (=y). The "add_one()" runs in user
space contexts in first scenario and as kernel space context in second
scenario. I'm not using modules so it worked for me.
Thanks,
Reviewed-by: Leon Romanovsky <leonro-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 7+ messages in thread
* RE: [PATCH rdma-rc] RDMA/restrack: don't use uaccess_kernel()
[not found] ` <20180213090122.GT2197-U/DQcQFIOTAAJjI8aNfphQ@public.gmane.org>
@ 2018-02-13 15:10 ` Steve Wise
0 siblings, 0 replies; 7+ messages in thread
From: Steve Wise @ 2018-02-13 15:10 UTC (permalink / raw)
To: 'Leon Romanovsky'
Cc: jgg-VPRAkNaXOzVWk0Htik3J/w, dledford-H+wXaHxf7aLQT0dZR+AlfA,
linux-rdma-u79uwXL29TY76Z2rM5mHXA
>
> On Thu, Feb 08, 2018 at 12:09:43PM -0800, Steve Wise wrote:
> > uaccess_kernel() isn't sufficient to determine if an rdma resource is
> > user-mode or not. For example, resources allocated in the add_one()
> > function of an ib_client get falsely labeled as user mode, when they
> > are kernel mode allocations. EG: mad qps.
>
> I found the reason.
>
> It is due to the difference between code compiled as
> a module (=m) or compiled in as monolith (=y). The "add_one()" runs in
user
> space contexts in first scenario and as kernel space context in second
> scenario. I'm not using modules so it worked for me.
>
> Thanks,
> Reviewed-by: Leon Romanovsky <leonro-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
Good to know. Thanks!
Steve.
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH rdma-rc] RDMA/restrack: don't use uaccess_kernel()
[not found] ` <eac01039be8c0518e37928e5b003a911c32e53a7.1518468700.git.swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
2018-02-13 9:01 ` Leon Romanovsky
@ 2018-02-15 21:58 ` Jason Gunthorpe
[not found] ` <20180215215854.GA16973-uk2M96/98Pc@public.gmane.org>
1 sibling, 1 reply; 7+ messages in thread
From: Jason Gunthorpe @ 2018-02-15 21:58 UTC (permalink / raw)
To: Steve Wise
Cc: dledford-H+wXaHxf7aLQT0dZR+AlfA, leon-DgEjT+Ai2ygdnm+yROfE0A,
linux-rdma-u79uwXL29TY76Z2rM5mHXA
On Thu, Feb 08, 2018 at 12:09:43PM -0800, Steve Wise wrote:
> + case RDMA_RESTRACK_QP:
> + qp = container_of(res, struct ib_qp, res);
> + if (qp->pd)
> + is_user = qp->pd->uobject;
?? Why is this like this?
struct ib_qp has a uboject, why do we need to look at the PD?
Jason
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 7+ messages in thread
* RE: [PATCH rdma-rc] RDMA/restrack: don't use uaccess_kernel()
[not found] ` <20180215215854.GA16973-uk2M96/98Pc@public.gmane.org>
@ 2018-02-15 22:04 ` Steve Wise
2018-02-15 22:41 ` Jason Gunthorpe
0 siblings, 1 reply; 7+ messages in thread
From: Steve Wise @ 2018-02-15 22:04 UTC (permalink / raw)
To: 'Jason Gunthorpe'
Cc: dledford-H+wXaHxf7aLQT0dZR+AlfA, leon-DgEjT+Ai2ygdnm+yROfE0A,
linux-rdma-u79uwXL29TY76Z2rM5mHXA
>
> On Thu, Feb 08, 2018 at 12:09:43PM -0800, Steve Wise wrote:
> > + case RDMA_RESTRACK_QP:
> > + qp = container_of(res, struct ib_qp, res);
> > + if (qp->pd)
> > + is_user = qp->pd->uobject;
>
> ?? Why is this like this?
>
> struct ib_qp has a uboject, why do we need to look at the PD?
I wasn't getting the correct user/kernel setting when I used qp->uobject.
Perhaps I should revisit this.
Steve.
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH rdma-rc] RDMA/restrack: don't use uaccess_kernel()
2018-02-15 22:04 ` Steve Wise
@ 2018-02-15 22:41 ` Jason Gunthorpe
[not found] ` <20180215224117.GA7803-uk2M96/98Pc@public.gmane.org>
0 siblings, 1 reply; 7+ messages in thread
From: Jason Gunthorpe @ 2018-02-15 22:41 UTC (permalink / raw)
To: Steve Wise
Cc: dledford-H+wXaHxf7aLQT0dZR+AlfA, leon-DgEjT+Ai2ygdnm+yROfE0A,
linux-rdma-u79uwXL29TY76Z2rM5mHXA
On Thu, Feb 15, 2018 at 04:04:02PM -0600, Steve Wise wrote:
> >
> > On Thu, Feb 08, 2018 at 12:09:43PM -0800, Steve Wise wrote:
> > > + case RDMA_RESTRACK_QP:
> > > + qp = container_of(res, struct ib_qp, res);
> > > + if (qp->pd)
> > > + is_user = qp->pd->uobject;
> >
> > ?? Why is this like this?
> >
> > struct ib_qp has a uboject, why do we need to look at the PD?
>
> I wasn't getting the correct user/kernel setting when I used qp->uobject.
> Perhaps I should revisit this.
Oh that answer certainly makes me nervous.. Let's explain that please
and either change it or add a big fat comment here about why it has to
be like this.
Thanks,
Jason
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 7+ messages in thread
* RE: [PATCH rdma-rc] RDMA/restrack: don't use uaccess_kernel()
[not found] ` <20180215224117.GA7803-uk2M96/98Pc@public.gmane.org>
@ 2018-02-16 15:47 ` Steve Wise
0 siblings, 0 replies; 7+ messages in thread
From: Steve Wise @ 2018-02-16 15:47 UTC (permalink / raw)
To: 'Jason Gunthorpe'
Cc: dledford-H+wXaHxf7aLQT0dZR+AlfA, leon-DgEjT+Ai2ygdnm+yROfE0A,
linux-rdma-u79uwXL29TY76Z2rM5mHXA
> > > On Thu, Feb 08, 2018 at 12:09:43PM -0800, Steve Wise wrote:
> > > > + case RDMA_RESTRACK_QP:
> > > > + qp = container_of(res, struct ib_qp, res);
> > > > + if (qp->pd)
> > > > + is_user = qp->pd->uobject;
> > >
> > > ?? Why is this like this?
> > >
> > > struct ib_qp has a uboject, why do we need to look at the PD?
> >
> > I wasn't getting the correct user/kernel setting when I used
qp->uobject.
> > Perhaps I should revisit this.
>
> Oh that answer certainly makes me nervous.. Let's explain that please
> and either change it or add a big fat comment here about why it has to
> be like this.
>
I see the problem: in uverbs_cmd.c:create_qp(), the call to _ib_create_qp()
happens before qp->uobject is initialized. I'll move the initialization of
qp->uobject to before the call to _ib_create_qp(), test it out, and send a
new patch.
Thanks Jason!
Steve.
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2018-02-16 15:47 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-02-08 20:09 [PATCH rdma-rc] RDMA/restrack: don't use uaccess_kernel() Steve Wise
[not found] ` <eac01039be8c0518e37928e5b003a911c32e53a7.1518468700.git.swise-7bPotxP6k4+P2YhJcF5u+vpXobYPEAuW@public.gmane.org>
2018-02-13 9:01 ` Leon Romanovsky
[not found] ` <20180213090122.GT2197-U/DQcQFIOTAAJjI8aNfphQ@public.gmane.org>
2018-02-13 15:10 ` Steve Wise
2018-02-15 21:58 ` Jason Gunthorpe
[not found] ` <20180215215854.GA16973-uk2M96/98Pc@public.gmane.org>
2018-02-15 22:04 ` Steve Wise
2018-02-15 22:41 ` Jason Gunthorpe
[not found] ` <20180215224117.GA7803-uk2M96/98Pc@public.gmane.org>
2018-02-16 15:47 ` Steve Wise
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.