August 2025 - Linux-stable-mirror

Backporting Selftests to Stable Kernels?

by Brett Sheffield

Dear Stable Maintainers, When a bugfix is backported to stable kernels, should we be backporting the associated selftest(s)? eg. 9e30ecf23b1b ("net: ipv4: fix incorrect MTU in broadcast routes") was backported to stable, but the selftest was not: 5777d1871bf6 ("selftests: net: add test for variable PMTU in broadcast routes") Does stable policy say whether it should be? It does not fix a bug, per se, but it does enable those of us running stable kernel tests to more thoroughly test stable RCs. Should mainline authors be encouraged to mark related tests for backporting? Cheers, Brett

1 week, 2 days

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FAILED: patch "[PATCH] drm/dp: Change AUX DPCD probe address from DPCD_REV to" failed to apply to 5.15-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.15-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(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x a40c5d727b8111b5db424a1e43e14a1dcce1e77f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025082151-chase-quilt-9ad4@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From a40c5d727b8111b5db424a1e43e14a1dcce1e77f Mon Sep 17 00:00:00 2001 From: Imre Deak <imre.deak(a)intel.com> Date: Thu, 5 Jun 2025 11:28:46 +0300 Subject: [PATCH] drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Reading DPCD registers has side-effects in general. In particular accessing registers outside of the link training register range (0x102-0x106, 0x202-0x207, 0x200c-0x200f, 0x2216) is explicitly forbidden by the DP v2.1 Standard, see 3.6.5.1 DPTX AUX Transaction Handling Mandates 3.6.7.4 128b/132b DP Link Layer LTTPR Link Training Mandates Based on my tests, accessing the DPCD_REV register during the link training of an UHBR TBT DP tunnel sink leads to link training failures. Solve the above by using the DP_LANE0_1_STATUS (0x202) register for the DPCD register access quirk. Cc: <stable(a)vger.kernel.org> Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com> Cc: Jani Nikula <jani.nikula(a)linux.intel.com> Acked-by: Jani Nikula <jani.nikula(a)intel.com> Signed-off-by: Imre Deak <imre.deak(a)intel.com> Link: https://lore.kernel.org/r/20250605082850.65136-2-imre.deak@intel.com diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c index f2a6559a2710..dc622c78db9d 100644 --- a/drivers/gpu/drm/display/drm_dp_helper.c +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -725,7 +725,7 @@ ssize_t drm_dp_dpcd_read(struct drm_dp_aux *aux, unsigned int offset, * monitor doesn't power down exactly after the throw away read. */ if (!aux->is_remote) { - ret = drm_dp_dpcd_probe(aux, DP_DPCD_REV); + ret = drm_dp_dpcd_probe(aux, DP_LANE0_1_STATUS); if (ret < 0) return ret; }

1 week, 2 days

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FAILED: patch "[PATCH] mptcp: remove duplicate sk_reset_timer call" failed to apply to 6.12-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.12-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(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y git checkout FETCH_HEAD git cherry-pick -x 5d13349472ac8abcbcb94407969aa0fdc2e1f1be # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025082229-sly-caution-e57f@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 5d13349472ac8abcbcb94407969aa0fdc2e1f1be Mon Sep 17 00:00:00 2001 From: Geliang Tang <geliang(a)kernel.org> Date: Fri, 15 Aug 2025 19:28:22 +0200 Subject: [PATCH] mptcp: remove duplicate sk_reset_timer call sk_reset_timer() was called twice in mptcp_pm_alloc_anno_list. Simplify the code by using a 'goto' statement to eliminate the duplication. Note that this is not a fix, but it will help backporting the following patch. The same "Fixes" tag has been added for this reason. Fixes: 93f323b9cccc ("mptcp: add a new sysctl add_addr_timeout") Cc: stable(a)vger.kernel.org Signed-off-by: Geliang Tang <tanggeliang(a)kylinos.cn> Reviewed-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org> Link: https://patch.msgid.link/20250815-net-mptcp-misc-fixes-6-17-rc2-v1-4-521fe9… Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c index 420d416e2603..c5f6a53ce5f1 100644 --- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -353,9 +353,7 @@ bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, if (WARN_ON_ONCE(mptcp_pm_is_kernel(msk))) return false; - sk_reset_timer(sk, &add_entry->add_timer, - jiffies + mptcp_get_add_addr_timeout(net)); - return true; + goto reset_timer; } add_entry = kmalloc(sizeof(*add_entry), GFP_ATOMIC); @@ -369,6 +367,7 @@ bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk, add_entry->retrans_times = 0; timer_setup(&add_entry->add_timer, mptcp_pm_add_timer, 0); +reset_timer: sk_reset_timer(sk, &add_entry->add_timer, jiffies + mptcp_get_add_addr_timeout(net));

1 week, 2 days

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FAILED: patch "[PATCH] iommu/virtio: Make instance lookup robust" failed to apply to 6.16-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.16-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(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.16.y git checkout FETCH_HEAD git cherry-pick -x 72b6f7cd89cea8251979b65528d302f9c0ed37bf # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025082258-exert-mousy-2b51@gregkh' --subject-prefix 'PATCH 6.16.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 72b6f7cd89cea8251979b65528d302f9c0ed37bf Mon Sep 17 00:00:00 2001 From: Robin Murphy <robin.murphy(a)arm.com> Date: Thu, 14 Aug 2025 17:47:16 +0100 Subject: [PATCH] iommu/virtio: Make instance lookup robust Much like arm-smmu in commit 7d835134d4e1 ("iommu/arm-smmu: Make instance lookup robust"), virtio-iommu appears to have the same issue where iommu_device_register() makes the IOMMU instance visible to other API callers (including itself) straight away, but internally the instance isn't ready to recognise itself for viommu_probe_device() to work correctly until after viommu_probe() has returned. This matters a lot more now that bus_iommu_probe() has the DT/VIOT knowledge to probe client devices the way that was always intended. Tweak the lookup and initialisation in much the same way as for arm-smmu, to ensure that what we register is functional and ready to go. Cc: stable(a)vger.kernel.org Fixes: bcb81ac6ae3c ("iommu: Get DT/ACPI parsing into the proper probe path") Signed-off-by: Robin Murphy <robin.murphy(a)arm.com> Tested-by: Eric Auger <eric.auger(a)redhat.com> Link: https://lore.kernel.org/r/308911aaa1f5be32a3a709996c7bd6cf71d30f33.17551900… Signed-off-by: Joerg Roedel <joerg.roedel(a)amd.com> diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c index 532db1de201b..b39d6f134ab2 100644 --- a/drivers/iommu/virtio-iommu.c +++ b/drivers/iommu/virtio-iommu.c @@ -998,8 +998,7 @@ static void viommu_get_resv_regions(struct device *dev, struct list_head *head) iommu_dma_get_resv_regions(dev, head); } -static const struct iommu_ops viommu_ops; -static struct virtio_driver virtio_iommu_drv; +static const struct bus_type *virtio_bus_type; static int viommu_match_node(struct device *dev, const void *data) { @@ -1008,8 +1007,9 @@ static int viommu_match_node(struct device *dev, const void *data) static struct viommu_dev *viommu_get_by_fwnode(struct fwnode_handle *fwnode) { - struct device *dev = driver_find_device(&virtio_iommu_drv.driver, NULL, - fwnode, viommu_match_node); + struct device *dev = bus_find_device(virtio_bus_type, NULL, fwnode, + viommu_match_node); + put_device(dev); return dev ? dev_to_virtio(dev)->priv : NULL; @@ -1160,6 +1160,9 @@ static int viommu_probe(struct virtio_device *vdev) if (!viommu) return -ENOMEM; + /* Borrow this for easy lookups later */ + virtio_bus_type = dev->bus; + spin_lock_init(&viommu->request_lock); ida_init(&viommu->domain_ids); viommu->dev = dev; @@ -1229,10 +1232,10 @@ static int viommu_probe(struct virtio_device *vdev) if (ret) goto err_free_vqs; - iommu_device_register(&viommu->iommu, &viommu_ops, parent_dev); - vdev->priv = viommu; + iommu_device_register(&viommu->iommu, &viommu_ops, parent_dev); + dev_info(dev, "input address: %u bits\n", order_base_2(viommu->geometry.aperture_end)); dev_info(dev, "page mask: %#llx\n", viommu->pgsize_bitmap);

1 week, 2 days

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FAILED: patch "[PATCH] cpuidle: governors: menu: Avoid selecting states with too" failed to apply to 6.6-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.6-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(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 779b1a1cb13ae17028aeddb2fbbdba97357a1e15 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025082216-despair-postnasal-6dbe@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 779b1a1cb13ae17028aeddb2fbbdba97357a1e15 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" <rafael.j.wysocki(a)intel.com> Date: Wed, 13 Aug 2025 12:25:58 +0200 Subject: [PATCH] cpuidle: governors: menu: Avoid selecting states with too much latency Occasionally, the exit latency of the idle state selected by the menu governor may exceed the PM QoS CPU wakeup latency limit. Namely, if the scheduler tick has been stopped already and predicted_ns is greater than the tick period length, the governor may return an idle state whose exit latency exceeds latency_req because that decision is made before checking the current idle state's exit latency. For instance, say that there are 3 idle states, 0, 1, and 2. For idle states 0 and 1, the exit latency is equal to the target residency and the values are 0 and 5 us, respectively. State 2 is deeper and has the exit latency and target residency of 200 us and 2 ms (which is greater than the tick period length), respectively. Say that predicted_ns is equal to TICK_NSEC and the PM QoS latency limit is 20 us. After the first two iterations of the main loop in menu_select(), idx becomes 1 and in the third iteration of it the target residency of the current state (state 2) is greater than predicted_ns. State 2 is not a polling one and predicted_ns is not less than TICK_NSEC, so the check on whether or not the tick has been stopped is done. Say that the tick has been stopped already and there are no imminent timers (that is, delta_tick is greater than the target residency of state 2). In that case, idx becomes 2 and it is returned immediately, but the exit latency of state 2 exceeds the latency limit. Address this issue by modifying the code to compare the exit latency of the current idle state (idle state i) with the latency limit before comparing its target residency with predicted_ns, which allows one more exit_latency_ns check that becomes redundant to be dropped. However, after the above change, latency_req cannot take the predicted_ns value any more, which takes place after commit 38f83090f515 ("cpuidle: menu: Remove iowait influence"), because it may cause a polling state to be returned prematurely. In the context of the previous example say that predicted_ns is 3000 and the PM QoS latency limit is still 20 us. Additionally, say that idle state 0 is a polling one. Moving the exit_latency_ns check before the target_residency_ns one causes the loop to terminate in the second iteration, before the target_residency_ns check, so idle state 0 will be returned even though previously state 1 would be returned if there were no imminent timers. For this reason, remove the assignment of the predicted_ns value to latency_req from the code. Fixes: 5ef499cd571c ("cpuidle: menu: Handle stopped tick more aggressively") Cc: 4.17+ <stable(a)vger.kernel.org> # 4.17+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> Reviewed-by: Christian Loehle <christian.loehle(a)arm.com> Link: https://patch.msgid.link/5043159.31r3eYUQgx@rafael.j.wysocki diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index 81306612a5c6..b2e3d0b0a116 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -287,20 +287,15 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, return 0; } - if (tick_nohz_tick_stopped()) { - /* - * If the tick is already stopped, the cost of possible short - * idle duration misprediction is much higher, because the CPU - * may be stuck in a shallow idle state for a long time as a - * result of it. In that case say we might mispredict and use - * the known time till the closest timer event for the idle - * state selection. - */ - if (predicted_ns < TICK_NSEC) - predicted_ns = data->next_timer_ns; - } else if (latency_req > predicted_ns) { - latency_req = predicted_ns; - } + /* + * If the tick is already stopped, the cost of possible short idle + * duration misprediction is much higher, because the CPU may be stuck + * in a shallow idle state for a long time as a result of it. In that + * case, say we might mispredict and use the known time till the closest + * timer event for the idle state selection. + */ + if (tick_nohz_tick_stopped() && predicted_ns < TICK_NSEC) + predicted_ns = data->next_timer_ns; /* * Find the idle state with the lowest power while satisfying @@ -316,13 +311,15 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, if (idx == -1) idx = i; /* first enabled state */ + if (s->exit_latency_ns > latency_req) + break; + if (s->target_residency_ns > predicted_ns) { /* * Use a physical idle state, not busy polling, unless * a timer is going to trigger soon enough. */ if ((drv->states[idx].flags & CPUIDLE_FLAG_POLLING) && - s->exit_latency_ns <= latency_req && s->target_residency_ns <= data->next_timer_ns) { predicted_ns = s->target_residency_ns; idx = i; @@ -354,8 +351,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, return idx; } - if (s->exit_latency_ns > latency_req) - break; idx = i; }

1 week, 2 days

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FAILED: patch "[PATCH] cpuidle: governors: menu: Avoid selecting states with too" failed to apply to 6.12-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.12-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(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y git checkout FETCH_HEAD git cherry-pick -x 779b1a1cb13ae17028aeddb2fbbdba97357a1e15 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025082214-daughter-popsicle-4c08@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 779b1a1cb13ae17028aeddb2fbbdba97357a1e15 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" <rafael.j.wysocki(a)intel.com> Date: Wed, 13 Aug 2025 12:25:58 +0200 Subject: [PATCH] cpuidle: governors: menu: Avoid selecting states with too much latency Occasionally, the exit latency of the idle state selected by the menu governor may exceed the PM QoS CPU wakeup latency limit. Namely, if the scheduler tick has been stopped already and predicted_ns is greater than the tick period length, the governor may return an idle state whose exit latency exceeds latency_req because that decision is made before checking the current idle state's exit latency. For instance, say that there are 3 idle states, 0, 1, and 2. For idle states 0 and 1, the exit latency is equal to the target residency and the values are 0 and 5 us, respectively. State 2 is deeper and has the exit latency and target residency of 200 us and 2 ms (which is greater than the tick period length), respectively. Say that predicted_ns is equal to TICK_NSEC and the PM QoS latency limit is 20 us. After the first two iterations of the main loop in menu_select(), idx becomes 1 and in the third iteration of it the target residency of the current state (state 2) is greater than predicted_ns. State 2 is not a polling one and predicted_ns is not less than TICK_NSEC, so the check on whether or not the tick has been stopped is done. Say that the tick has been stopped already and there are no imminent timers (that is, delta_tick is greater than the target residency of state 2). In that case, idx becomes 2 and it is returned immediately, but the exit latency of state 2 exceeds the latency limit. Address this issue by modifying the code to compare the exit latency of the current idle state (idle state i) with the latency limit before comparing its target residency with predicted_ns, which allows one more exit_latency_ns check that becomes redundant to be dropped. However, after the above change, latency_req cannot take the predicted_ns value any more, which takes place after commit 38f83090f515 ("cpuidle: menu: Remove iowait influence"), because it may cause a polling state to be returned prematurely. In the context of the previous example say that predicted_ns is 3000 and the PM QoS latency limit is still 20 us. Additionally, say that idle state 0 is a polling one. Moving the exit_latency_ns check before the target_residency_ns one causes the loop to terminate in the second iteration, before the target_residency_ns check, so idle state 0 will be returned even though previously state 1 would be returned if there were no imminent timers. For this reason, remove the assignment of the predicted_ns value to latency_req from the code. Fixes: 5ef499cd571c ("cpuidle: menu: Handle stopped tick more aggressively") Cc: 4.17+ <stable(a)vger.kernel.org> # 4.17+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com> Reviewed-by: Christian Loehle <christian.loehle(a)arm.com> Link: https://patch.msgid.link/5043159.31r3eYUQgx@rafael.j.wysocki diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index 81306612a5c6..b2e3d0b0a116 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -287,20 +287,15 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, return 0; } - if (tick_nohz_tick_stopped()) { - /* - * If the tick is already stopped, the cost of possible short - * idle duration misprediction is much higher, because the CPU - * may be stuck in a shallow idle state for a long time as a - * result of it. In that case say we might mispredict and use - * the known time till the closest timer event for the idle - * state selection. - */ - if (predicted_ns < TICK_NSEC) - predicted_ns = data->next_timer_ns; - } else if (latency_req > predicted_ns) { - latency_req = predicted_ns; - } + /* + * If the tick is already stopped, the cost of possible short idle + * duration misprediction is much higher, because the CPU may be stuck + * in a shallow idle state for a long time as a result of it. In that + * case, say we might mispredict and use the known time till the closest + * timer event for the idle state selection. + */ + if (tick_nohz_tick_stopped() && predicted_ns < TICK_NSEC) + predicted_ns = data->next_timer_ns; /* * Find the idle state with the lowest power while satisfying @@ -316,13 +311,15 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, if (idx == -1) idx = i; /* first enabled state */ + if (s->exit_latency_ns > latency_req) + break; + if (s->target_residency_ns > predicted_ns) { /* * Use a physical idle state, not busy polling, unless * a timer is going to trigger soon enough. */ if ((drv->states[idx].flags & CPUIDLE_FLAG_POLLING) && - s->exit_latency_ns <= latency_req && s->target_residency_ns <= data->next_timer_ns) { predicted_ns = s->target_residency_ns; idx = i; @@ -354,8 +351,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, return idx; } - if (s->exit_latency_ns > latency_req) - break; idx = i; }

1 week, 2 days

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FAILED: patch "[PATCH] drm/dp: Change AUX DPCD probe address from DPCD_REV to" failed to apply to 6.1-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.1-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(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x a40c5d727b8111b5db424a1e43e14a1dcce1e77f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025082150-fiddle-impure-4da2@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From a40c5d727b8111b5db424a1e43e14a1dcce1e77f Mon Sep 17 00:00:00 2001 From: Imre Deak <imre.deak(a)intel.com> Date: Thu, 5 Jun 2025 11:28:46 +0300 Subject: [PATCH] drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Reading DPCD registers has side-effects in general. In particular accessing registers outside of the link training register range (0x102-0x106, 0x202-0x207, 0x200c-0x200f, 0x2216) is explicitly forbidden by the DP v2.1 Standard, see 3.6.5.1 DPTX AUX Transaction Handling Mandates 3.6.7.4 128b/132b DP Link Layer LTTPR Link Training Mandates Based on my tests, accessing the DPCD_REV register during the link training of an UHBR TBT DP tunnel sink leads to link training failures. Solve the above by using the DP_LANE0_1_STATUS (0x202) register for the DPCD register access quirk. Cc: <stable(a)vger.kernel.org> Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com> Cc: Jani Nikula <jani.nikula(a)linux.intel.com> Acked-by: Jani Nikula <jani.nikula(a)intel.com> Signed-off-by: Imre Deak <imre.deak(a)intel.com> Link: https://lore.kernel.org/r/20250605082850.65136-2-imre.deak@intel.com diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c index f2a6559a2710..dc622c78db9d 100644 --- a/drivers/gpu/drm/display/drm_dp_helper.c +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -725,7 +725,7 @@ ssize_t drm_dp_dpcd_read(struct drm_dp_aux *aux, unsigned int offset, * monitor doesn't power down exactly after the throw away read. */ if (!aux->is_remote) { - ret = drm_dp_dpcd_probe(aux, DP_DPCD_REV); + ret = drm_dp_dpcd_probe(aux, DP_LANE0_1_STATUS); if (ret < 0) return ret; }

1 week, 2 days

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FAILED: patch "[PATCH] drm/amd: Restore cached manual clock settings during resume" failed to apply to 6.16-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.16-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(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.16.y git checkout FETCH_HEAD git cherry-pick -x 796ff8a7e01bd18738d3bb4111f9d6f963145d29 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025082108-oil-trailing-aa0d@gregkh' --subject-prefix 'PATCH 6.16.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 796ff8a7e01bd18738d3bb4111f9d6f963145d29 Mon Sep 17 00:00:00 2001 From: Mario Limonciello <mario.limonciello(a)amd.com> Date: Thu, 24 Jul 2025 22:12:22 -0500 Subject: [PATCH] drm/amd: Restore cached manual clock settings during resume If the SCLK limits have been set before S3 they will not be restored. The limits are however cached in the driver and so they can be restored by running a commit sequence during resume. Acked-by: Alex Deucher <alexander.deucher(a)amd.com> Link: https://lore.kernel.org/r/20250725031222.3015095-3-superm1@kernel.org Signed-off-by: Mario Limonciello <mario.limonciello(a)amd.com> Signed-off-by: Alex Deucher <alexander.deucher(a)amd.com> (cherry picked from commit 4e9526924d09057a9ba854305e17eded900ced82) Cc: stable(a)vger.kernel.org diff --git a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c index 310f51ff05b9..b47cb4a5f488 100644 --- a/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c +++ b/drivers/gpu/drm/amd/pm/swsmu/amdgpu_smu.c @@ -77,6 +77,9 @@ static void smu_power_profile_mode_get(struct smu_context *smu, static void smu_power_profile_mode_put(struct smu_context *smu, enum PP_SMC_POWER_PROFILE profile_mode); static enum smu_clk_type smu_convert_to_smuclk(enum pp_clock_type type); +static int smu_od_edit_dpm_table(void *handle, + enum PP_OD_DPM_TABLE_COMMAND type, + long *input, uint32_t size); static int smu_sys_get_pp_feature_mask(void *handle, char *buf) @@ -2195,6 +2198,7 @@ static int smu_resume(struct amdgpu_ip_block *ip_block) int ret; struct amdgpu_device *adev = ip_block->adev; struct smu_context *smu = adev->powerplay.pp_handle; + struct smu_dpm_context *smu_dpm_ctx = &(smu->smu_dpm); if (amdgpu_sriov_multi_vf_mode(adev)) return 0; @@ -2232,6 +2236,12 @@ static int smu_resume(struct amdgpu_ip_block *ip_block) return ret; } + if (smu_dpm_ctx->dpm_level == AMD_DPM_FORCED_LEVEL_MANUAL) { + ret = smu_od_edit_dpm_table(smu, PP_OD_COMMIT_DPM_TABLE, NULL, 0); + if (ret) + return ret; + } + dev_info(adev->dev, "SMU is resumed successfully!\n"); return 0;

1 week, 2 days

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FAILED: patch "[PATCH] drm/dp: Change AUX DPCD probe address from DPCD_REV to" failed to apply to 6.6-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.6-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(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x a40c5d727b8111b5db424a1e43e14a1dcce1e77f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025082149-disfigure-divinely-bc5c@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From a40c5d727b8111b5db424a1e43e14a1dcce1e77f Mon Sep 17 00:00:00 2001 From: Imre Deak <imre.deak(a)intel.com> Date: Thu, 5 Jun 2025 11:28:46 +0300 Subject: [PATCH] drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Reading DPCD registers has side-effects in general. In particular accessing registers outside of the link training register range (0x102-0x106, 0x202-0x207, 0x200c-0x200f, 0x2216) is explicitly forbidden by the DP v2.1 Standard, see 3.6.5.1 DPTX AUX Transaction Handling Mandates 3.6.7.4 128b/132b DP Link Layer LTTPR Link Training Mandates Based on my tests, accessing the DPCD_REV register during the link training of an UHBR TBT DP tunnel sink leads to link training failures. Solve the above by using the DP_LANE0_1_STATUS (0x202) register for the DPCD register access quirk. Cc: <stable(a)vger.kernel.org> Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com> Cc: Jani Nikula <jani.nikula(a)linux.intel.com> Acked-by: Jani Nikula <jani.nikula(a)intel.com> Signed-off-by: Imre Deak <imre.deak(a)intel.com> Link: https://lore.kernel.org/r/20250605082850.65136-2-imre.deak@intel.com diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c index f2a6559a2710..dc622c78db9d 100644 --- a/drivers/gpu/drm/display/drm_dp_helper.c +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -725,7 +725,7 @@ ssize_t drm_dp_dpcd_read(struct drm_dp_aux *aux, unsigned int offset, * monitor doesn't power down exactly after the throw away read. */ if (!aux->is_remote) { - ret = drm_dp_dpcd_probe(aux, DP_DPCD_REV); + ret = drm_dp_dpcd_probe(aux, DP_LANE0_1_STATUS); if (ret < 0) return ret; }

1 week, 2 days

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FAILED: patch "[PATCH] drm/dp: Change AUX DPCD probe address from DPCD_REV to" failed to apply to 6.12-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.12-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(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y git checkout FETCH_HEAD git cherry-pick -x a40c5d727b8111b5db424a1e43e14a1dcce1e77f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025082149-baggy-limpness-3f61@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From a40c5d727b8111b5db424a1e43e14a1dcce1e77f Mon Sep 17 00:00:00 2001 From: Imre Deak <imre.deak(a)intel.com> Date: Thu, 5 Jun 2025 11:28:46 +0300 Subject: [PATCH] drm/dp: Change AUX DPCD probe address from DPCD_REV to LANE0_1_STATUS MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Reading DPCD registers has side-effects in general. In particular accessing registers outside of the link training register range (0x102-0x106, 0x202-0x207, 0x200c-0x200f, 0x2216) is explicitly forbidden by the DP v2.1 Standard, see 3.6.5.1 DPTX AUX Transaction Handling Mandates 3.6.7.4 128b/132b DP Link Layer LTTPR Link Training Mandates Based on my tests, accessing the DPCD_REV register during the link training of an UHBR TBT DP tunnel sink leads to link training failures. Solve the above by using the DP_LANE0_1_STATUS (0x202) register for the DPCD register access quirk. Cc: <stable(a)vger.kernel.org> Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com> Cc: Jani Nikula <jani.nikula(a)linux.intel.com> Acked-by: Jani Nikula <jani.nikula(a)intel.com> Signed-off-by: Imre Deak <imre.deak(a)intel.com> Link: https://lore.kernel.org/r/20250605082850.65136-2-imre.deak@intel.com diff --git a/drivers/gpu/drm/display/drm_dp_helper.c b/drivers/gpu/drm/display/drm_dp_helper.c index f2a6559a2710..dc622c78db9d 100644 --- a/drivers/gpu/drm/display/drm_dp_helper.c +++ b/drivers/gpu/drm/display/drm_dp_helper.c @@ -725,7 +725,7 @@ ssize_t drm_dp_dpcd_read(struct drm_dp_aux *aux, unsigned int offset, * monitor doesn't power down exactly after the throw away read. */ if (!aux->is_remote) { - ret = drm_dp_dpcd_probe(aux, DP_DPCD_REV); + ret = drm_dp_dpcd_probe(aux, DP_LANE0_1_STATUS); if (ret < 0) return ret; }

1 week, 2 days

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