| 55f2ea9f | 30-May-2026 |
Bjorn Andersson <bjorn.andersson@oss.qualcomm.com> |
slimbus: qcom-ngd-ctrl: Avoid ABBA on tx_lock/ctrl->lock
During the SSR/PDR down notification the tx_lock is taken with the
intent to provide synchronization with active DMA transfers.
But during t
slimbus: qcom-ngd-ctrl: Avoid ABBA on tx_lock/ctrl->lock
During the SSR/PDR down notification the tx_lock is taken with the
intent to provide synchronization with active DMA transfers.
But during this period qcom_slim_ngd_down() is invoked, which ends up in
slim_report_absent(), which takes the slim_controller lock. In multiple
other codepaths these two locks are taken in the opposite order (i.e.
slim_controller then tx_lock).
The result is a lockdep splat, and a possible deadlock:
rprocctl/449 is trying to acquire lock:
ffff00009793e620 (&ctrl->lock){+.+.}-{4:4}, at: slim_report_absent (drivers/slimbus/core.c:322) slimbus
but task is already holding lock:
ffff00009793fb50 (&ctrl->tx_lock){+.+.}-{4:4}, at: qcom_slim_ngd_ssr_pdr_notify (drivers/slimbus/qcom-ngd-ctrl.c:1475) slim_qcom_ngd_ctrl
which lock already depends on the new lock.
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ctrl->tx_lock);
lock(&ctrl->lock);
lock(&ctrl->tx_lock);
lock(&ctrl->lock);
The assumption is that the comment refers to the desire to not call
qcom_slim_ngd_exit_dma() while we have an ongoing DMA TX transaction.
But any such transaction is initiated and completed within a single
qcom_slim_ngd_xfer_msg().
Prior to calling qcom_slim_ngd_exit_dma() the slim_controller is torn
down, all child devices are notified that the slimbus is gone and the
child devices are removed.
Stop taking the tx_lock in qcom_slim_ngd_ssr_pdr_notify() to avoid the
deadlock.
Fixes: a899d324863a ("slimbus: qcom-ngd-ctrl: add Sub System Restart support")
Cc: stable@vger.kernel.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20260530204421.116824-9-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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| 6a003446 | 30-May-2026 |
Bjorn Andersson <bjorn.andersson@oss.qualcomm.com> |
slimbus: qcom-ngd-ctrl: Balance pm_runtime enablement for NGD
The pm_runtime_enable() and pm_runtime_use_autosuspend() calls are
supposed to be balanced on exit, add these calls.
Fixes: 917809e2280
slimbus: qcom-ngd-ctrl: Balance pm_runtime enablement for NGD
The pm_runtime_enable() and pm_runtime_use_autosuspend() calls are
supposed to be balanced on exit, add these calls.
Fixes: 917809e2280b ("slimbus: ngd: Add qcom SLIMBus NGD driver")
Cc: stable@vger.kernel.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20260530204421.116824-8-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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| 07c564ea | 30-May-2026 |
Bjorn Andersson <bjorn.andersson@oss.qualcomm.com> |
slimbus: qcom-ngd-ctrl: Initialize controller resources in controller
The work structs and work queue are controller resources, create and
destroy them in the controller context. Creating them as pa
slimbus: qcom-ngd-ctrl: Initialize controller resources in controller
The work structs and work queue are controller resources, create and
destroy them in the controller context. Creating them as part of the
child device's probe path seems to be okay now that the controller's
probe has been updated, but if for some reason the child does not probe
successfully a SSR or PDR notification will schedule_work() on an
uninitialized "ngd_up_work".
Move the initialization of these controller resources to the controller
probe function to avoid any issues, and to clarify the ownership.
Fixes: 917809e2280b ("slimbus: ngd: Add qcom SLIMBus NGD driver")
Cc: stable@vger.kernel.org
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20260530204421.116824-7-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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| 2a9d50e9 | 30-May-2026 |
Bjorn Andersson <bjorn.andersson@oss.qualcomm.com> |
slimbus: qcom-ngd-ctrl: Register callbacks after creating the ngd
When the remoteproc starts in parallel with the NGD driver being probed,
or the remoteproc is already up when the PDR lookup is bein
slimbus: qcom-ngd-ctrl: Register callbacks after creating the ngd
When the remoteproc starts in parallel with the NGD driver being probed,
or the remoteproc is already up when the PDR lookup is being registered,
or in the theoretical event that we get an interrupt from the hardware,
these callbacks will operate on uninitialized data. This result in
issues to boot the affected boards.
One such example can be seen in the following fault, where
qcom_slim_ngd_ssr_pdr_notify() schedules work on the NULL ngd_up_work.
[ 21.858578] ------------[ cut here ]------------
[ 21.858745] WARNING: kernel/workqueue.c:2338 at __queue_work+0x5e0/0x790, CPU#2: kworker/2:2/116
...
[ 21.859251] Call trace:
[ 21.859255] __queue_work+0x5e0/0x790 (P)
[ 21.859265] queue_work_on+0x6c/0xf0
[ 21.859273] qcom_slim_ngd_ssr_pdr_notify+0x110/0x150 [slim_qcom_ngd_ctrl]
[ 21.859304] qcom_slim_ngd_ssr_notify+0x24/0x40 [slim_qcom_ngd_ctrl]
[ 21.859318] notifier_call_chain+0xa4/0x230
[ 21.859329] srcu_notifier_call_chain+0x64/0xb8
[ 21.859338] ssr_notify_start+0x40/0x78 [qcom_common]
[ 21.859355] rproc_start+0x130/0x230
[ 21.859367] rproc_boot+0x3d4/0x518
...
Move the enablement of interrupts, and the registration of SSR and PDR
until after the NGD device has been registered.
This could be further refined by moving initialization to the control
driver probe and by removing the platform driver model from the picture.
Fixes: 917809e2280b ("slimbus: ngd: Add qcom SLIMBus NGD driver")
Cc: stable@vger.kernel.org
Reviewed-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20260530204421.116824-6-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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| 960b53a3 | 30-May-2026 |
Bjorn Andersson <bjorn.andersson@oss.qualcomm.com> |
slimbus: qcom-ngd-ctrl: Correct PDR and SSR cleanup ownership
PDR and SSR callbacks are registred from the controller probe function,
but currently released from the child device's remove function.
slimbus: qcom-ngd-ctrl: Correct PDR and SSR cleanup ownership
PDR and SSR callbacks are registred from the controller probe function,
but currently released from the child device's remove function.
The remove() function should only be unwinding what was done in the
same device's probe() function.
Fixes: 917809e2280b ("slimbus: ngd: Add qcom SLIMBus NGD driver")
Cc: stable@vger.kernel.org
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20260530204421.116824-5-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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| 2c22ff15 | 30-May-2026 |
Bjorn Andersson <bjorn.andersson@oss.qualcomm.com> |
slimbus: qcom-ngd-ctrl: Fix probe error path ordering
qcom_slim_ngd_ctrl_probe() first registers the SSR callback then
allocates the PDR context, as such the error path needs to come in
opposite ord
slimbus: qcom-ngd-ctrl: Fix probe error path ordering
qcom_slim_ngd_ctrl_probe() first registers the SSR callback then
allocates the PDR context, as such the error path needs to come in
opposite order to allow us to unroll each step.
Fixes: 16f14551d0df ("slimbus: qcom-ngd: cleanup in probe error path")
Cc: stable@vger.kernel.org
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20260530204421.116824-4-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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| 8663e833 | 30-May-2026 |
Bjorn Andersson <bjorn.andersson@oss.qualcomm.com> |
slimbus: qcom-ngd-ctrl: Fix up platform_driver registration
Device drivers should not invoke platform_driver_register()/unregister()
in their probe and remove paths. They should further not rely on
slimbus: qcom-ngd-ctrl: Fix up platform_driver registration
Device drivers should not invoke platform_driver_register()/unregister()
in their probe and remove paths. They should further not rely on
platform_driver_unregister() as their only means of "deleting" their
child devices.
Introduce a helper to unregister the child device and move the
platform_driver_register()/unregister() to module_init()/exit().
Fixes: 917809e2280b ("slimbus: ngd: Add qcom SLIMBus NGD driver")
Cc: stable@vger.kernel.org
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Reviewed-by: Mukesh Ojha <mukesh.ojha@oss.qualcomm.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@oss.qualcomm.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://patch.msgid.link/20260530204421.116824-3-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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| bba7fd12 | 26-Nov-2025 |
Johan Hovold <johan@kernel.org> |
slimbus: core: clean up of_slim_get_device()
Clean up of_find_slim_device() by folding in the of_find_slim_device()
helper.
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.
slimbus: core: clean up of_slim_get_device()
Clean up of_find_slim_device() by folding in the of_find_slim_device()
helper.
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20251126145329.5022-7-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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| 7831f710 | 26-Nov-2025 |
Johan Hovold <johan@kernel.org> |
slimbus: core: fix of_slim_get_device() kernel doc
Unlike slim_get_device() the of_slim_get_device() helper does not
allocate and register any slimbus devices in case lookup fails.
Update the of_sl
slimbus: core: fix of_slim_get_device() kernel doc
Unlike slim_get_device() the of_slim_get_device() helper does not
allocate and register any slimbus devices in case lookup fails.
Update the of_slim_get_device() kernel doc to reflect this and add a
comment about the helper taking a reference to the returned device.
Fixes: e0772de8a48b ("slimbus: core: add of_slim_device_get() helper")
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20251126145329.5022-6-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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| 4c6da2fd | 26-Nov-2025 |
Johan Hovold <johan@kernel.org> |
slimbus: core: amend slim_get_device() kernel doc
Add a comment to clarify that slim_get_device() takes a reference to
the embedded struct device of the returned slimbus device.
Signed-off-by: Joha
slimbus: core: amend slim_get_device() kernel doc
Add a comment to clarify that slim_get_device() takes a reference to
the embedded struct device of the returned slimbus device.
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20251126145329.5022-5-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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| 9391380e | 26-Nov-2025 |
Johan Hovold <johan@kernel.org> |
slimbus: core: fix device reference leak on report present
Slimbus devices can be allocated dynamically upon reception of
report-present messages.
Make sure to drop the reference taken when looking
slimbus: core: fix device reference leak on report present
Slimbus devices can be allocated dynamically upon reception of
report-present messages.
Make sure to drop the reference taken when looking up already registered
devices.
Note that this requires taking an extra reference in case the device has
not yet been registered and has to be allocated.
Fixes: 46a2bb5a7f7e ("slimbus: core: Add slim controllers support")
Cc: stable@vger.kernel.org # 4.16
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20251126145329.5022-4-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
show more ...
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| 0eb4ff65 | 26-Nov-2025 |
Johan Hovold <johan@kernel.org> |
slimbus: core: fix runtime PM imbalance on report present
Make sure to balance the runtime PM usage count in case slimbus device
or address allocation fails on report present, which would otherwise
slimbus: core: fix runtime PM imbalance on report present
Make sure to balance the runtime PM usage count in case slimbus device
or address allocation fails on report present, which would otherwise
prevent the controller from suspending.
Fixes: 4b14e62ad3c9 ("slimbus: Add support for 'clock-pause' feature")
Cc: stable@vger.kernel.org # 4.16
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://patch.msgid.link/20251126145329.5022-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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| ae0de633 | 12-Sep-2025 |
Xichao Zhao <zhao.xichao@vivo.com> |
slimbus: messaging: fix "transfered"->"transferred"
Trivial fix to spelling mistake in comment text.
Signed-off-by: Xichao Zhao <zhao.xichao@vivo.com>
Signed-off-by: Srinivas Kandagatla <srini@kern
slimbus: messaging: fix "transfered"->"transferred"
Trivial fix to spelling mistake in comment text.
Signed-off-by: Xichao Zhao <zhao.xichao@vivo.com>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://lore.kernel.org/r/20250912131202.303026-4-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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| 5c6794f1 | 12-Sep-2025 |
Qiang Liu <liuqiang@kylinos.cn> |
slimbus: messaging: Remove redundant code
Assigning txn->comp to itself has no effect.
Signed-off-by: Qiang Liu <liuqiang@kylinos.cn>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: htt
slimbus: messaging: Remove redundant code
Assigning txn->comp to itself has no effect.
Signed-off-by: Qiang Liu <liuqiang@kylinos.cn>
Signed-off-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://lore.kernel.org/r/20250912131202.303026-3-srini@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
show more ...
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