FAILED: patch "[PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale" failed to apply to 5.13-stable tree

FAILED: patch "[PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale" failed to apply to 5.13-stable tree

[gregkh]

The patch below does not apply to the 5.13-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 3769e4c0af5b82c8ea21d037013cb9564dfaa51f Mon Sep 17 00:00:00 2001
From: Wayne Lin <Wayne.Lin@amd.com>
Date: Wed, 16 Jun 2021 11:55:01 +0800
Subject: [PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale
 topology

[Why]
After unplug/hotplug hub from the system, userspace might start to
clear stale payloads gradually. If we call drm_dp_mst_deallocate_vcpi()
to release stale VCPI of those ports which are not relating to current
topology, we have chane to wrongly clear active payload table entry for
current topology.

E.g.
We have allocated VCPI 1 in current payload table and we call
drm_dp_mst_deallocate_vcpi() to clean VCPI 1 in stale topology. In
drm_dp_mst_deallocate_vcpi(), it will call drm_dp_mst_put_payload_id()
tp put VCPI 1 and which means ID 1 is available again. Thereafter, if we
want to allocate a new payload stream, it will find ID 1 is available by
drm_dp_mst_assign_payload_id(). However, ID 1 is being used

[How]
Check target sink is relating to current topology or not before doing
any payload table update.
Searching upward to find the target sink's relevant root branch device.
If the found root branch device is not the same root of current
topology, don't update payload table.

Changes since v1:
* Change debug macro to use drm_dbg_kms() instead
* Amend the commit message to add Cc tag.

Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210616035501.3776-3-Wayne.Lin@amd.com
Reviewed-by: Lyude Paul <lyude@redhat.com>

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index b41b837db66d..9ac148efd9e4 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -94,6 +94,9 @@ static int drm_dp_mst_register_i2c_bus(struct drm_dp_mst_port *port);
 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_mst_port *port);
 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);
 
+static bool drm_dp_mst_port_downstream_of_branch(struct drm_dp_mst_port *port,
+						 struct drm_dp_mst_branch *branch);
+
 #define DBG_PREFIX "[dp_mst]"
 
 #define DP_STR(x) [DP_ ## x] = #x
@@ -3366,6 +3369,7 @@ int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
 	struct drm_dp_mst_port *port;
 	int i, j;
 	int cur_slots = 1;
+	bool skip;
 
 	mutex_lock(&mgr->payload_lock);
 	for (i = 0; i < mgr->max_payloads; i++) {
@@ -3380,6 +3384,14 @@ int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
 			port = container_of(vcpi, struct drm_dp_mst_port,
 					    vcpi);
 
+			mutex_lock(&mgr->lock);
+			skip = !drm_dp_mst_port_downstream_of_branch(port, mgr->mst_primary);
+			mutex_unlock(&mgr->lock);
+
+			if (skip) {
+				drm_dbg_kms("Virtual channel %d is not in current topology\n", i);
+				continue;
+			}
 			/* Validated ports don't matter if we're releasing
 			 * VCPI
 			 */
@@ -3479,6 +3491,7 @@ int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
 	struct drm_dp_mst_port *port;
 	int i;
 	int ret = 0;
+	bool skip;
 
 	mutex_lock(&mgr->payload_lock);
 	for (i = 0; i < mgr->max_payloads; i++) {
@@ -3488,6 +3501,13 @@ int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
 
 		port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
 
+		mutex_lock(&mgr->lock);
+		skip = !drm_dp_mst_port_downstream_of_branch(port, mgr->mst_primary);
+		mutex_unlock(&mgr->lock);
+
+		if (skip)
+			continue;
+
 		drm_dbg_kms(mgr->dev, "payload %d %d\n", i, mgr->payloads[i].payload_state);
 		if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
 			ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
@@ -4574,9 +4594,18 @@ EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 				struct drm_dp_mst_port *port)
 {
+	bool skip;
+
 	if (!port->vcpi.vcpi)
 		return;
 
+	mutex_lock(&mgr->lock);
+	skip = !drm_dp_mst_port_downstream_of_branch(port, mgr->mst_primary);
+	mutex_unlock(&mgr->lock);
+
+	if (skip)
+		return;
+
 	drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
 	port->vcpi.num_slots = 0;
 	port->vcpi.pbn = 0;

FAILED: patch "[PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale" failed to apply to 5.13-stable tree

[gregkh]

The patch below does not apply to the 5.13-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 3769e4c0af5b82c8ea21d037013cb9564dfaa51f Mon Sep 17 00:00:00 2001
From: Wayne Lin <Wayne.Lin@amd.com>
Date: Wed, 16 Jun 2021 11:55:01 +0800
Subject: [PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale
 topology

[Why]
After unplug/hotplug hub from the system, userspace might start to
clear stale payloads gradually. If we call drm_dp_mst_deallocate_vcpi()
to release stale VCPI of those ports which are not relating to current
topology, we have chane to wrongly clear active payload table entry for
current topology.

E.g.
We have allocated VCPI 1 in current payload table and we call
drm_dp_mst_deallocate_vcpi() to clean VCPI 1 in stale topology. In
drm_dp_mst_deallocate_vcpi(), it will call drm_dp_mst_put_payload_id()
tp put VCPI 1 and which means ID 1 is available again. Thereafter, if we
want to allocate a new payload stream, it will find ID 1 is available by
drm_dp_mst_assign_payload_id(). However, ID 1 is being used

[How]
Check target sink is relating to current topology or not before doing
any payload table update.
Searching upward to find the target sink's relevant root branch device.
If the found root branch device is not the same root of current
topology, don't update payload table.

Changes since v1:
* Change debug macro to use drm_dbg_kms() instead
* Amend the commit message to add Cc tag.

Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210616035501.3776-3-Wayne.Lin@amd.com
Reviewed-by: Lyude Paul <lyude@redhat.com>

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index b41b837db66d..9ac148efd9e4 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -94,6 +94,9 @@ static int drm_dp_mst_register_i2c_bus(struct drm_dp_mst_port *port);
 static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_mst_port *port);
 static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr);
 
+static bool drm_dp_mst_port_downstream_of_branch(struct drm_dp_mst_port *port,
+						 struct drm_dp_mst_branch *branch);
+
 #define DBG_PREFIX "[dp_mst]"
 
 #define DP_STR(x) [DP_ ## x] = #x
@@ -3366,6 +3369,7 @@ int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
 	struct drm_dp_mst_port *port;
 	int i, j;
 	int cur_slots = 1;
+	bool skip;
 
 	mutex_lock(&mgr->payload_lock);
 	for (i = 0; i < mgr->max_payloads; i++) {
@@ -3380,6 +3384,14 @@ int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
 			port = container_of(vcpi, struct drm_dp_mst_port,
 					    vcpi);
 
+			mutex_lock(&mgr->lock);
+			skip = !drm_dp_mst_port_downstream_of_branch(port, mgr->mst_primary);
+			mutex_unlock(&mgr->lock);
+
+			if (skip) {
+				drm_dbg_kms("Virtual channel %d is not in current topology\n", i);
+				continue;
+			}
 			/* Validated ports don't matter if we're releasing
 			 * VCPI
 			 */
@@ -3479,6 +3491,7 @@ int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
 	struct drm_dp_mst_port *port;
 	int i;
 	int ret = 0;
+	bool skip;
 
 	mutex_lock(&mgr->payload_lock);
 	for (i = 0; i < mgr->max_payloads; i++) {
@@ -3488,6 +3501,13 @@ int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
 
 		port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
 
+		mutex_lock(&mgr->lock);
+		skip = !drm_dp_mst_port_downstream_of_branch(port, mgr->mst_primary);
+		mutex_unlock(&mgr->lock);
+
+		if (skip)
+			continue;
+
 		drm_dbg_kms(mgr->dev, "payload %d %d\n", i, mgr->payloads[i].payload_state);
 		if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
 			ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]);
@@ -4574,9 +4594,18 @@ EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
 void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
 				struct drm_dp_mst_port *port)
 {
+	bool skip;
+
 	if (!port->vcpi.vcpi)
 		return;
 
+	mutex_lock(&mgr->lock);
+	skip = !drm_dp_mst_port_downstream_of_branch(port, mgr->mst_primary);
+	mutex_unlock(&mgr->lock);
+
+	if (skip)
+		return;
+
 	drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
 	port->vcpi.num_slots = 0;
 	port->vcpi.pbn = 0;

RE: FAILED: patch "[PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale" failed to apply to 5.13-stable tree

[Lin, Wayne]

[AMD Official Use Only]

Hi Greg,

Really thanks for your time. About failing to apply below patches to stable tree:
3769e4c0af5b82c8ea21d037013cb9564dfaa51f
[PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale topology

35d3e8cb35e75450f87f87e3d314e2d418b6954b
 [PATCH] drm/dp_mst: Do not set proposed vcpi directly

There was an immediate following patch to correct the issue caused by above patches:
24ff3dc18b99c4b912ab1746e803ddb3be5ced4c
[PATCH] drm/dp_mst: Add missing drm parameters to recently added call to drm_dbg_kms()

In other words, these three patches should be committed at the same time. Sorry for any inconvenience it brought.
Please advise me if there is anything else to do for having these patches applied to stable tree.
Really thanks for your help.

Regards,
Wayne

> -----Original Message-----
> From: gregkh@linuxfoundation.org <gregkh@linuxfoundation.org>
> Sent: Thursday, July 15, 2021 8:17 PM
> To: Lin, Wayne <Wayne.Lin@amd.com>; lyude@redhat.com
> Cc: stable@vger.kernel.org
> Subject: FAILED: patch "[PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale" failed to apply to 5.13-stable tree
>
>
> The patch below does not apply to the 5.13-stable tree.
> If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git
> commit id to <stable@vger.kernel.org>.
>
> thanks,
>
> greg k-h
>
> ------------------ original commit in Linus's tree ------------------
>
> From 3769e4c0af5b82c8ea21d037013cb9564dfaa51f Mon Sep 17 00:00:00 2001
> From: Wayne Lin <Wayne.Lin@amd.com>
> Date: Wed, 16 Jun 2021 11:55:01 +0800
> Subject: [PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale  topology
>
> [Why]
> After unplug/hotplug hub from the system, userspace might start to clear stale payloads gradually. If we call
> drm_dp_mst_deallocate_vcpi() to release stale VCPI of those ports which are not relating to current topology, we have chane to
> wrongly clear active payload table entry for current topology.
>
> E.g.
> We have allocated VCPI 1 in current payload table and we call
> drm_dp_mst_deallocate_vcpi() to clean VCPI 1 in stale topology. In drm_dp_mst_deallocate_vcpi(), it will call
> drm_dp_mst_put_payload_id() tp put VCPI 1 and which means ID 1 is available again. Thereafter, if we want to allocate a new payload
> stream, it will find ID 1 is available by drm_dp_mst_assign_payload_id(). However, ID 1 is being used
>
> [How]
> Check target sink is relating to current topology or not before doing any payload table update.
> Searching upward to find the target sink's relevant root branch device.
> If the found root branch device is not the same root of current topology, don't update payload table.
>
> Changes since v1:
> * Change debug macro to use drm_dbg_kms() instead
> * Amend the commit message to add Cc tag.
>
> Signed-off-by: Wayne Lin <Wayne.Lin@amd.com>
> Cc: stable@vger.kernel.org
> Signed-off-by: Lyude Paul <lyude@redhat.com>
> Link:
> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatchwork.freedesktop.org%2Fpatch%2Fmsgid%2F20210616
> 035501.3776-3-
> Wayne.Lin%40amd.com&amp;data=04%7C01%7CWayne.Lin%40amd.com%7C231171835e1e4d40019a08d9478c7553%7C3dd8961fe488
> 4e608e11a82d994e183d%7C0%7C0%7C637619490858271159%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luM
> zIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=ry%2FBe6oKXqA51GAiVYSsl4RqIoGZ%2BT9%2FsVbqMD1OlXc%3D&amp;r
> eserved=0
> Reviewed-by: Lyude Paul <lyude@redhat.com>
>
> diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
> index b41b837db66d..9ac148efd9e4 100644
> --- a/drivers/gpu/drm/drm_dp_mst_topology.c
> +++ b/drivers/gpu/drm/drm_dp_mst_topology.c
> @@ -94,6 +94,9 @@ static int drm_dp_mst_register_i2c_bus(struct drm_dp_mst_port *port);  static void
> drm_dp_mst_unregister_i2c_bus(struct drm_dp_mst_port *port);  static void drm_dp_mst_kick_tx(struct
> drm_dp_mst_topology_mgr *mgr);
>
> +static bool drm_dp_mst_port_downstream_of_branch(struct drm_dp_mst_port *port,
> +                                              struct drm_dp_mst_branch *branch);
> +
>  #define DBG_PREFIX "[dp_mst]"
>
>  #define DP_STR(x) [DP_ ## x] = #x
> @@ -3366,6 +3369,7 @@ int drm_dp_update_payload_part1(struct drm_dp_mst_topology_mgr *mgr)
>       struct drm_dp_mst_port *port;
>       int i, j;
>       int cur_slots = 1;
> +     bool skip;
>
>       mutex_lock(&mgr->payload_lock);
>       for (i = 0; i < mgr->max_payloads; i++) { @@ -3380,6 +3384,14 @@ int drm_dp_update_payload_part1(struct
> drm_dp_mst_topology_mgr *mgr)
>                       port = container_of(vcpi, struct drm_dp_mst_port,
>                                           vcpi);
>
> +                     mutex_lock(&mgr->lock);
> +                     skip = !drm_dp_mst_port_downstream_of_branch(port, mgr->mst_primary);
> +                     mutex_unlock(&mgr->lock);
> +
> +                     if (skip) {
> +                             drm_dbg_kms("Virtual channel %d is not in current topology\n", i);
> +                             continue;
> +                     }
>                       /* Validated ports don't matter if we're releasing
>                        * VCPI
>                        */
> @@ -3479,6 +3491,7 @@ int drm_dp_update_payload_part2(struct drm_dp_mst_topology_mgr *mgr)
>       struct drm_dp_mst_port *port;
>       int i;
>       int ret = 0;
> +     bool skip;
>
>       mutex_lock(&mgr->payload_lock);
>       for (i = 0; i < mgr->max_payloads; i++) { @@ -3488,6 +3501,13 @@ int drm_dp_update_payload_part2(struct
> drm_dp_mst_topology_mgr *mgr)
>
>               port = container_of(mgr->proposed_vcpis[i], struct drm_dp_mst_port, vcpi);
>
> +             mutex_lock(&mgr->lock);
> +             skip = !drm_dp_mst_port_downstream_of_branch(port, mgr->mst_primary);
> +             mutex_unlock(&mgr->lock);
> +
> +             if (skip)
> +                     continue;
> +
>               drm_dbg_kms(mgr->dev, "payload %d %d\n", i, mgr->payloads[i].payload_state);
>               if (mgr->payloads[i].payload_state == DP_PAYLOAD_LOCAL) {
>                       ret = drm_dp_create_payload_step2(mgr, port, mgr->proposed_vcpis[i]->vcpi, &mgr->payloads[i]); @@ -
> 4574,9 +4594,18 @@ EXPORT_SYMBOL(drm_dp_mst_reset_vcpi_slots);
>  void drm_dp_mst_deallocate_vcpi(struct drm_dp_mst_topology_mgr *mgr,
>                               struct drm_dp_mst_port *port)
>  {
> +     bool skip;
> +
>       if (!port->vcpi.vcpi)
>               return;
>
> +     mutex_lock(&mgr->lock);
> +     skip = !drm_dp_mst_port_downstream_of_branch(port, mgr->mst_primary);
> +     mutex_unlock(&mgr->lock);
> +
> +     if (skip)
> +             return;
> +
>       drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
>       port->vcpi.num_slots = 0;
>       port->vcpi.pbn = 0;

Re: FAILED: patch "[PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale" failed to apply to 5.13-stable tree

[gregkh]

On Thu, Jul 15, 2021 at 03:07:19PM +0000, Lin, Wayne wrote:
> [AMD Official Use Only]
> 
> Hi Greg,
> 
> Really thanks for your time. About failing to apply below patches to stable tree:
> 3769e4c0af5b82c8ea21d037013cb9564dfaa51f
> [PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale topology
> 
> 35d3e8cb35e75450f87f87e3d314e2d418b6954b
>  [PATCH] drm/dp_mst: Do not set proposed vcpi directly
> 
> There was an immediate following patch to correct the issue caused by above patches:
> 24ff3dc18b99c4b912ab1746e803ddb3be5ced4c
> [PATCH] drm/dp_mst: Add missing drm parameters to recently added call to drm_dbg_kms()
> 
> In other words, these three patches should be committed at the same time. Sorry for any inconvenience it brought.
> Please advise me if there is anything else to do for having these patches applied to stable tree.
> Really thanks for your help.

These commits do not apply to the current stable trees, so please submit
backports of them for how ever far back you wish to see them, so that we
can apply them.

thanks,

greg k-h

RE: FAILED: patch "[PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale" failed to apply to 5.13-stable tree

[Lin, Wayne]

[AMD Official Use Only]

> -----Original Message-----
> From: gregkh@linuxfoundation.org <gregkh@linuxfoundation.org>
> Sent: Friday, July 16, 2021 1:28 AM
> To: Lin, Wayne <Wayne.Lin@amd.com>
> Cc: lyude@redhat.com; stable@vger.kernel.org
> Subject: Re: FAILED: patch "[PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale" failed to apply to 5.13-stable tree
>
> On Thu, Jul 15, 2021 at 03:07:19PM +0000, Lin, Wayne wrote:
> > [AMD Official Use Only]
> >
> > Hi Greg,
> >
> > Really thanks for your time. About failing to apply below patches to stable tree:
> > 3769e4c0af5b82c8ea21d037013cb9564dfaa51f
> > [PATCH] drm/dp_mst: Avoid to mess up payload table by ports in stale
> > topology
> >
> > 35d3e8cb35e75450f87f87e3d314e2d418b6954b
> >  [PATCH] drm/dp_mst: Do not set proposed vcpi directly
> >
> > There was an immediate following patch to correct the issue caused by above patches:
> > 24ff3dc18b99c4b912ab1746e803ddb3be5ced4c
> > [PATCH] drm/dp_mst: Add missing drm parameters to recently added call
> > to drm_dbg_kms()
> >
> > In other words, these three patches should be committed at the same time. Sorry for any inconvenience it brought.
> > Please advise me if there is anything else to do for having these patches applied to stable tree.
> > Really thanks for your help.
>
> These commits do not apply to the current stable trees, so please submit backports of them for how ever far back you wish to see
> them, so that we can apply them.
Hi Greg,

I see. Thanks for your time! Will do.

Regards,
Wayne
>
> thanks,
>
> greg k-h