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2026-05-29firmware: samsung: acpm: Make acpm_ops const and access via pointerTudor Ambarus
Replace the embedded `struct acpm_ops` inside `struct acpm_handle` with a pointer to a `const struct acpm_ops`. Previously, the operations structure was embedded directly within the handle and populated dynamically at runtime via `acpm_setup_ops()`. This resulted in mutable function pointers and unnecessary per-instance memory overhead. By defining `exynos_acpm_driver_ops` statically as a `const` structure, the function pointers are now safely housed in the read-only `.rodata` section. This improves security by preventing function pointer overwrites, saves memory, and slightly reduces initialization overhead in `acpm_probe()`. Consequently, update all consumer drivers (clk, mfd) to access the operations via the new pointer indirection (`->ops->`). Finally, fix the previously empty kernel-doc description for the ops member to reflect its new pointer nature. Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> Reviewed-by: Peter Griffin <peter.griffin@linaro.org> Link: https://patch.msgid.link/20260515-acpm-tmu-helpers-v2-4-8ca011d5a965@linaro.org Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
2026-05-29firmware: samsung: acpm: Drop redundant _ops suffix in acpm_ops membersTudor Ambarus
Rename the `dvfs_ops` and `pmic_ops` members of `struct acpm_ops` to `dvfs` and `pmic` respectively. Since these members are housed within the `acpm_ops` structure and utilize the `acpm_*_ops` types, the `_ops` suffix on the variable names creates unnecessary redundancy (e.g., `handle.ops.dvfs_ops`). This cleanup removes the stuttering, leading to cleaner consumer code. Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> Reviewed-by: Peter Griffin <peter.griffin@linaro.org> Acked-by: Lee Jones <lee@kernel.org> Link: https://lore.kernel.org/linux-samsung-soc/CADrjBPqzKpcd9vuCmNUptCUPyPpPbHcc19-7kN-1c0RpW1e5DQ@mail.gmail.com/T/#mcce154a7e0c6cd1ca6cd5a1e37541ed7a85a84d4 [1] Link: https://patch.msgid.link/20260515-acpm-tmu-helpers-v2-3-8ca011d5a965@linaro.org Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
2026-05-29firmware: samsung: acpm: Annotate rx_data->cmd with __counted_by_ptrTudor Ambarus
Rename the `n_cmd` member of `struct acpm_rx_data` to `cmdcnt` to maintain consistent nomenclature across the driver (aligning with `txcnt`, `rxcnt`, and transfer helpers). With the member renamed, annotate the dynamically allocated `cmd` pointer with the `__counted_by_ptr(cmdcnt)` macro to improve runtime bounds checking. Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> Reviewed-by: Peter Griffin <peter.griffin@linaro.org> Link: https://patch.msgid.link/20260515-acpm-tmu-helpers-v2-2-8ca011d5a965@linaro.org Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
2026-05-29firmware: samsung: acpm: Consolidate transfer initialization helperTudor Ambarus
Both the DVFS and PMIC ACPM sub-drivers implement similar local helper functions (acpm_dvfs_set_xfer and acpm_pmic_set_xfer) to initialize the acpm_xfer structure before sending an IPC message. Move this logic into a single centralized helper, acpm_set_xfer(), in the core ACPM driver to reduce boilerplate, eliminate code duplication, and prepare for the upcoming ACPM TMU helper sub-driver which will also utilize this method. Note that there is no change in underlying functionality. While the old acpm_pmic_set_xfer() unconditionally assigned the RX buffer parameters (xfer->rxd and xfer->rxcnt), the new unified helper introduces a 'response' boolean. All updated PMIC call sites now explicitly pass 'true' for this argument. This ensures the unified helper takes the 'if (response)' branch, performing the exact same assignments and preserving the original PMIC behavior. Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> Reviewed-by: Peter Griffin <peter.griffin@linaro.org> Link: https://patch.msgid.link/20260515-acpm-tmu-helpers-v2-1-8ca011d5a965@linaro.org Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
2026-05-29drm/xe/ggtt: Fix xe_ggtt documentationMichal Wajdeczko
The following error is reported during the htmldocs build: ... Documentation/gpu/xe/xe_mm:22: ../drivers/gpu/drm/xe/xe_ggtt.c:125: ERROR: Unexpected indentation. [docutils] Fix this by adding a blank line before the enumeration. While around correct some invalid spaces. Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com> Reviewed-by: Maarten Lankhorst <dev@lankhorst.se> Link: https://patch.msgid.link/20260527122154.22480-1-michal.wajdeczko@intel.com
2026-05-29RDMA/rxe: Fix typos in commentsPurushothaman Ramalingam
Fix typos found by codespell in driver comments: rxe.c: s/mangagement/management/ rxe_param.h: s/interations/iterations/ rxe_resp.c: s/recive/receive/ No functional change. Link: https://patch.msgid.link/r/20260527104527.3222-1-purush.ramalingam@gmail.com Signed-off-by: Purushothaman Ramalingam <purush.ramalingam@gmail.com> Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2026-05-29mmc: dw_mmc: Add desc_num field for clarityShawn Lin
The ring_size field in struct dw_mci is misleadingly named. Despite its name, it does not represent the size of the descriptor ring buffer in bytes, but rather the number of descriptors allocated within the fixed-size ring buffer. The actual ring buffer size is fixed at PAGE_SIZE (or DESC_RING_BUF_SZ, which equals PAGE_SIZE). Within this buffer, we allocate either struct idmac_desc or struct idmac_desc_64addr descriptors, and ring_size stores the count of these descriptors. This naming has caused confusion, as it's also used to set mmc->max_segs (the maximum number of scatter-gather segments), which logically corresponds to the number of descriptors, not a size in bytes. No functional change is introduced by this naming-only patch. Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29mmc: sdhci: add signal voltage switch in sdhci_resume_hostJisheng Zhang
I met one suspend/resume issue with sdr104 capable sdio wifi card (with "keep-power-in-suspend" set in DT property): After resuming from suspend to ram, the sdio wifi card stops working. Further debug shows that although ios shows the sdio card is at sdr104 mode, the voltage is still at 3V3. This is due to missing the calling of ->start_signal_voltage_switch() in sdhci_resume_host(). Fix this issue by adding ->start_signal_voltage_switch() in sdhci_resume_host(). This also matches what we do for sdhci_runtime_resume_host(). Then the question is: why this issue hasn't reported and fixed for so long time. IMHO, several reasons: Some host controllers just kick off the runtime resume for system resume, so they benefit from the well supported runtime pm code; Some platforms just use the old sdio wifi card which doesn't need signal voltage switch at all, the default voltage is 3v3 after resuming. Fixes: 6308d2905bd3 ("mmc: sdhci: add quirk for keeping card power during suspend") Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29mmc: dw_mmc-rockchip: Add missing private data for very old controllersHeiko Stuebner
The really old controllers (rk2928, rk3066, rk3188) do not support UHS speeds at all, and thus never handled phase data. For that reason it never had a parse_dt callback and no driver private data at all. Commit ff6f0286c896 ("mmc: dw_mmc-rockchip: Add memory clock auto-gating support") makes the private data sort of mandatory, because the init function checks whether phases are configured internally or through the clock controller. This results in the old SoCs then experiencing NULL-pointer dereferences when they try to access that private-data struct. While we could have if (priv) conditionals in all places, it's way less cluttery to just give the old types their private-data struct. Fixes: ff6f0286c896 ("mmc: dw_mmc-rockchip: Add memory clock auto-gating support") Cc: stable@vger.kernel.org Signed-off-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Shawn Lin <shawn.lin@rock-chips.com> Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29mmc: sdhci-of-dwcmshc: use dev_err_probe() to simplify error pathsArtem Shimko
Replace common pattern of dev_err() + return with dev_err_probe() in probe functions and their callees. This macro provides standardized error message format with symbolic error names and adds deferred probe debugging information. The conversion makes the code more compact and ensures consistent error logging across all initialization paths. Acked-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Artem Shimko <a.shimko.dev@gmail.com> Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29mmc: sdhci-of-dwcmshc: remove redundant IS_ERR() checkArtem Shimko
The clk_disable_unprepare() function has internal protection against ERR_PTR and NULL pointers (IS_ERR_OR_NULL). Remove the redundant IS_ERR() check for bus_clk in dwcmshc_suspend() and in the error path of dwcmshc_resume() to simplify the code. Note that the clk_prepare_enable() call in dwcmshc_resume() must retain its IS_ERR() check because clk_prepare() only handles NULL pointers, not ERR_PTR. No functional change intended. Acked-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Artem Shimko <a.shimko.dev@gmail.com> Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29Merge branch 'acpi-driver-devm'Rafael J. Wysocki
Merge updates that introduce devm_acpi_install_notify_handler() and convert some drivers for core ACPI devices previously using acpi_dev_install_notify_handler() to devres-based resource management. * acpi-driver-devm: ACPI: video: Switch over to devres-based resource management ACPI: video: Use devm for video->entry and backlight cleanup ACPI: video: Use devm action for freeing video devices ACPI: video: Use devm action for video bus object cleanup ACPI: video: Rearrange probe and remove code ACPI: video: Reduce the number of auxiliary device dereferences ACPI: PAD: Switch over to devres-based resource management ACPI: PAD: Fix teardown ordering in acpi_pad_remove() ACPI: PAD: Pass struct device pointer to acpi_pad_notify() ACPI: PAD: Rearrange acpi_pad_notify() ACPI: thermal: Switch over to devres-based resource management ACPI: HED: Switch over to devres-based resource management ACPI: HED: Refine guarding against adding a second instance ACPI: battery: Switch over to devres-based resource management ACPI: AC: Switch over to devres-based resource management ACPI: NFIT: core: Use devm_acpi_install_notify_handler() ACPI: bus: Introduce devm_acpi_install_notify_handler()
2026-05-29mmc: litex_mmc: Set mandatory idle clocks before CMD0Inochi Amaoto
The litex_mmc driver assumes the card is already probed in the BIOS and skip the phy initialization. This will cause the command fail like the following when the old card is unplugged and then insert a new card: [ 62.923593] litex-mmc f0004000.mmc: Command (cmd 8) error, status -110 [ 62.949717] litex-mmc f0004000.mmc: Command (cmd 55) error, status -110 [ 62.976606] litex-mmc f0004000.mmc: Command (cmd 55) error, status -110 [ 63.002516] litex-mmc f0004000.mmc: Command (cmd 55) error, status -110 [ 63.028442] litex-mmc f0004000.mmc: Command (cmd 55) error, status -110 Add required clock settings and initialization for the CMD 0, so it can probe the new card. Fixes: 92e099104729 ("mmc: Add driver for LiteX's LiteSDCard interface") Signed-off-by: Inochi Amaoto <inochiama@gmail.com> Reviewed-by: Gabriel Somlo <gsomlo@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29Merge branch 'acpi-pmic'Rafael J. Wysocki
Merge an ACPI PMIC driver cleanup for 7.2. * acpi-pmic: ACPI: PMIC: Replace mutex_lock/unlock() with guard()/scoped_guard()
2026-05-29mmc: litex_mmc: Use DIV_ROUND_UP for more accurate clock calculationInochi Amaoto
The previous clock uses roundup_pow_of_two() to calculate the core clock frequency. It does not meet the actual hardware meaning. The actual frequency is calculated by "ref_clk / ((div >> 1) << 1)". Fix the clock divider calculation. Fixes: 92e099104729 ("mmc: Add driver for LiteX's LiteSDCard interface") Signed-off-by: Inochi Amaoto <inochiama@gmail.com> Reviewed-by: Gabriel Somlo <gsomlo@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29Merge branch 'acpi-video'Rafael J. Wysocki
Merge an ACPI video bus driver cleanup for 7.2. * acpi-video: ACPI: video: Do not initialise device_id_scheme directly
2026-05-29soc: renesas: rcar-mfis: Add R-Car V4H/V4M supportWolfram Sang
The above SoCs have a weird register layout for the mailbox registers. So, encapsulate register offset calculation in a per-SoC callback. Other than that, only a separate config struct and compatibles are needed. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://patch.msgid.link/20260519075620.4128-3-wsa+renesas@sang-engineering.com Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
2026-05-29soc/tegra: Use ARM SMCCC to get chip ID, revision, and platform infoKartik Rajput
Tegra410 and Tegra241 deprecate the HIDREV register. The recommended method is to use ARM SMCCC to retrieve the chip ID, major and minor revisions, and platform information. Prefer ARM SMCCC when the platform supports it; fall back to HIDREV otherwise. Behavior on older Tegra SoCs that do not support ARM SMCCC remains unchanged. Signed-off-by: Kartik Rajput <kkartik@nvidia.com> Signed-off-by: Thierry Reding <treding@nvidia.com>
2026-05-29Merge back earlier cpufreq material for 7.2Rafael J. Wysocki
2026-05-29mmc: renesas_sdhi: Add OF entry for RZ/G2E SoCLad Prabhakar
The RZ/G2E (R8A774C0) SoC was previously handled via the generic "renesas,rcar-gen3-sdhi" fallback compatible string. However, because the SDHI IP on RZ/G2E is identical with the R-Car E3 (R8A77990), it requires the specific quirks and configuration defined in `of_r8a77990_compatible` rather than the generic Gen3 data. Add the explicit "renesas,sdhi-r8a774c0" match entry to map it correctly. Note that the DT binding file renesas,sdhi.yaml does not need an update as the entry for this SoC is already present. Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29mmc: renesas_sdhi: Add OF entry for RZ/G2N SoCLad Prabhakar
The RZ/G2N (R8A774B1) SoC was previously handled via the generic "renesas,rcar-gen3-sdhi" fallback compatible string. However, because the SDHI IP on RZ/G2N is identical with the R-Car M3-N (R8A77965), it requires the specific quirks and configuration defined in `of_r8a77965_compatible` rather than the generic Gen3 data. Add the explicit "renesas,sdhi-r8a774b1" match entry to map it correctly. Note that the DT binding file renesas,sdhi.yaml does not need an update as the entry for this SoC is already present. Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29drm/tegra: dsi: Re-add clear enable register if DSI was powered by bootloaderSvyatoslav Ryhel
Original commit b22fd0b9639e ("drm/tegra: dsi: Clear enable register if powered by bootloader") was added to address the issue of DSI being in an unknown state after the bootloader, ensuring correct panel configuration. This worked fairly well under the assumption that the bootloader had set up DSI; however, in cases where it did not, the device would hang because a DSI read was called before the DSI hardware was ready. Removing this workaround results in the issue described in the original fix: the panel initialization sequence fails and the panel gets stuck in an undefined state. This is especially noticeable with command mode panels In order to properly address this issue, the original workaround is restored and placed after the DSI hardware is prepared for R/W operations. This fixes behavior for both cases: where DSI is set by the bootloader and where DSI is untouched. I have tested this change on Tegra20 (Motorola Atrix 4G), Tegra114 (NVIDIA Tegra Note 7 and ASUS Transformer Pad TF701T), and Tegra124 (Xiaomi Mi Pad) with U-Boot, using both bootloader-initialized DSI and untouched DSI. Fixes: b22fd0b9639e ("drm/tegra: dsi: Clear enable register if powered by bootloader") Fixes: 660b299bed2a ("Revert "drm/tegra: dsi: Clear enable register if powered by bootloader"") Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com> Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com> Signed-off-by: Thierry Reding <treding@nvidia.com> Link: https://patch.msgid.link/20260511074538.24563-3-clamor95@gmail.com
2026-05-29mmc: Merge branch fixes into nextUlf Hansson
Merge the mmc fixes for v7.1-rc[n] into the next branch, to allow them to get tested together with the mmc changes that are targeted for the next release. Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29drm/tegra: dsi: Add support for Tegra20/Tegra30Svyatoslav Ryhel
Tegra20 and Tegra30 are fully compatible with existing Tegra DSI driver apart from clock configuration and pad calibration which are addressed by this patch. Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com> Reviewed-by: Mikko Perttunen <mperttunen@nvidia.com> Signed-off-by: Thierry Reding <treding@nvidia.com> Link: https://patch.msgid.link/20260511074538.24563-2-clamor95@gmail.com
2026-05-29mmc: renesas_sdhi: Add OF entry for RZ/G2H SoCLad Prabhakar
The RZ/G2H (R8A774E1) SoC was previously handled via the generic "renesas,rcar-gen3-sdhi" fallback compatible string. However, because the SDHI IP on RZ/G2H is identical with the R-Car H3-N (R8A77951), it requires the specific quirks and configuration defined in `of_r8a7795_compatible` rather than the generic Gen3 data. Add the explicit "renesas,sdhi-r8a774e1" match entry to map it correctly. Note that the DT binding file renesas,sdhi.yaml does not need an update as the entry for this SoC is already present. Fixes: 31941342888d ("arm64: dts: renesas: r8a774e1: Add SDHI nodes") Cc: stable@vger.kernel.org Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29mmc: davinci: fix mmc_add_host order in probeOsama Abdelkader
mmc_add_host() makes the host visible to the MMC core. Register the interrupt handlers and advertise MMC_CAP_SDIO_IRQ before that, so the core cannot start using the host before IRQ handling is set up. Signed-off-by: Osama Abdelkader <osama.abdelkader@gmail.com> Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29mmc: sdhci-of-dwcmshc: Fix reset, clk, and SDIO support for Eswin EIC7700Huan He
The EIC7700 code in sdhci-of-dwcmshc uses host->mmc->caps2 to select different configuration paths for different card types. The current logic distinguishes eMMC and SD, but does not handle SDIO separately. Update the EIC7700 card-type checks so that eMMC, SD and SDIO are distinguished explicitly. Switch the reset path to dwcmshc_reset() so that pending interrupt state is cleared consistently, and use sdhci_enable_clk() so the clock enable sequence follows the standard SDHCI flow. Fixes: 32b2633219d3 ("mmc: sdhci-of-dwcmshc: Add support for Eswin EIC7700") Signed-off-by: Huan He <hehuan1@eswincomputing.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson <ulfh@kernel.org>
2026-05-29firmware: samsung: acpm: Fix infinite loop on sequence number exhaustionTudor Ambarus
Sashiko identified a possible infinite loop [1]. ACPM IPC sequence numbers are tracked via a 64-bit bitmap. Previously, acpm_prepare_xfer() used a do...while loop to search for a free sequence number. If all 63 available sequence numbers are leaked due to transient hardware timeouts or mailbox failures, the bitmap becomes full. The next call to acpm_prepare_xfer() would enter an infinite loop. Fix this by utilizing the kernel's optimized bitmap search functions (find_next_zero_bit / find_first_zero_bit). If the pool is completely exhausted, log the failure and return -EBUSY to allow the kernel to fail gracefully instead of hanging. Furthermore, drop the allocation loop entirely. Because acpm_prepare_xfer() is strictly called under the 'tx_lock' mutex, sequence number allocations are perfectly serialized. If find_next_zero_bit() locates a free bit, a single test_and_set_bit_lock() is mathematically guaranteed to succeed. To enforce this locking invariant, wrap the allocation in a WARN_ON_ONCE. If the atomic set fails, it indicates the driver's mutex serialization is fundamentally broken. The warning generates a stack trace for debugging, while returning -EIO immediately aborts the transfer to prevent silent payload corruption. Cc: stable@vger.kernel.org Fixes: a88927b534ba ("firmware: add Exynos ACPM protocol driver") Closes: https://sashiko.dev/#/patchset/20260420-acpm-tmu-v3-0-3dc8e93f0b26%40linaro.org [1] Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> Link: https://patch.msgid.link/20260505-acpm-fixes-sashiko-reports-v5-7-43b5ee7f1674@linaro.org Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
2026-05-29firmware: samsung: acpm: Fix missing LKMM barriers in sequence allocatorTudor Ambarus
Sashiko identified memory ordering races in [1]. The ACPM driver uses a globally shared 'bitmap_seqnum' to track available sequence numbers. Even though threads now strictly free their own sequence numbers, the allocation and freeing of these bits across concurrent threads are effectively lockless operations and require explicit LKMM memory barriers. Previously, the driver used plain bitwise operators (test_bit, set_bit, clear_bit), which lack ordering guarantees. This creates two race conditions on weakly ordered architectures like ARM64: 1. Polling Release Violation: The polling thread copies its payload and calls clear_bit(). Without a release barrier, the CPU can reorder the memory operations, making the cleared bit globally visible before the payload reads have fully completed. 2. TX Acquire Violation: The TX thread loops on test_bit(), calls set_bit(), and then wipes the payload buffer via memset(). Without an acquire barrier, the CPU can speculatively execute the memset() before the bit is safely and formally claimed. If these reorderings overlap, a new TX thread can claim the sequence number and overwrite the buffer while the original polling thread is still actively reading from it. Fix this by upgrading the bitwise operators. Wrap the TX allocation in test_and_set_bit_lock() to establish formal LKMM Acquire semantics, and pair it with clear_bit_unlock() in the polling path to enforce Release semantics. Cc: stable@vger.kernel.org Fixes: a88927b534ba ("firmware: add Exynos ACPM protocol driver") Closes: https://sashiko.dev/#/patchset/20260423-acpm-fixes-sashiko-reports-v1-0-2217b790925e%40linaro.org [1] Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> Link: https://patch.msgid.link/20260505-acpm-fixes-sashiko-reports-v5-6-43b5ee7f1674@linaro.org Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
2026-05-29firmware: samsung: acpm: Fix false timeouts and Use-After-Free in pollingTudor Ambarus
Sashiko identified severe races in the polling state machine [1]. In the ACPM driver's polling mode, threads waited for responses by monitoring the globally shared 'bitmap_seqnum'. This caused false timeouts because if a thread processed its response and freed the sequence number, a concurrent TX thread could immediately reallocate it before the polling thread woke up. Additionally, the driver suffered from a cross-thread Use-After-Free (UAF) preemption race. Previously, acpm_get_rx() cleared the sequence number of whichever RX message it drained from the hardware queue. This meant Thread A could globally free Thread B's sequence slot while Thread B was asleep. A new Thread C could then steal the slot, overwrite the buffer, and leave Thread B to wake up to corrupted state or a timeout. Fix this by rewriting the polling state machine: 1. Decouple polling from the global allocator by introducing a per-slot 'completed' flag, synchronized via smp_store_release() and smp_load_acquire(). 2. Strip acpm_get_saved_rx() out of acpm_get_rx() to make it a pure queue-draining function. Introduce a 'native_match' boolean argument which evaluates to true only if the thread natively processed its own sequence number during the call. This explicitly informs the polling loop whether it must retrieve its payload from the cross-thread cache. 3. Centralize the cache fallback and sequence number free (clear_bit) inside the polling loop. Crucially, the free operation now strictly targets the thread's own TX sequence number (xfer->txd[0]), rather than the drained RX sequence number. This enforces strict ownership: a thread only ever frees its own allocated sequence slot, and only at the exact moment it completes its poll, eliminating the UAF window. Furthermore, explicitly guard the 'native_match' assignment with an if (rx_seqnum == tx_seqnum) check, even for zero-length (no payload) responses. While an unguarded assignment wouldn't crash (because the cache fallback acpm_get_saved_rx() safely returns early on zero-length transfers) doing so would "lie" to the state machine. If a thread drained the queue and found another thread's zero-length message, setting native_match = true would falsely convince the polling loop that it natively handled its own response. Maintaining a rigorous state machine requires that native_match is only set when a thread explicitly processes its own sequence number. Cc: stable@vger.kernel.org Fixes: a88927b534ba ("firmware: add Exynos ACPM protocol driver") Closes: https://sashiko.dev/#/patchset/20260429-acpm-fixes-sashiko-reports-v3-0-47cf74ab09ad%40linaro.org [1] Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org> Link: https://patch.msgid.link/20260505-acpm-fixes-sashiko-reports-v5-5-43b5ee7f1674@linaro.org Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
2026-05-29drm/msm: Restore second parameter name in purge() and evict()Nathan Chancellor
After commit 3392291fc509 ("drm/msm: Fix shrinker deadlock"), all supported versions of clang warn (or error with CONFIG_WERROR=y): drivers/gpu/drm/msm/msm_gem_shrinker.c:105:58: error: omitting the parameter name in a function definition is a C23 extension [-Werror,-Wc23-extensions] 105 | purge(struct drm_gem_object *obj, struct ww_acquire_ctx *) | ^ drivers/gpu/drm/msm/msm_gem_shrinker.c:117:58: error: omitting the parameter name in a function definition is a C23 extension [-Werror,-Wc23-extensions] 117 | evict(struct drm_gem_object *obj, struct ww_acquire_ctx *) | ^ 2 errors generated. With older but supported versions of GCC, this is an unconditional hard error: drivers/gpu/drm/msm/msm_gem_shrinker.c: In function 'purge': drivers/gpu/drm/msm/msm_gem_shrinker.c:105:35: error: parameter name omitted purge(struct drm_gem_object *obj, struct ww_acquire_ctx *) ^~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/msm/msm_gem_shrinker.c: In function 'evict': drivers/gpu/drm/msm/msm_gem_shrinker.c:117:35: error: parameter name omitted evict(struct drm_gem_object *obj, struct ww_acquire_ctx *) ^~~~~~~~~~~~~~~~~~~~~~~ Restore the parameter name to clear up the warnings, renaming it "unused" to make it clear it is only needed to satisfy the prototype of drm_gem_lru_scan(). Cc: stable@vger.kernel.org Fixes: 3392291fc509 ("drm/msm: Fix shrinker deadlock") Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Patchwork: https://patchwork.freedesktop.org/patch/725924/ Link: https://lore.kernel.org/r/20260518-drm-msm-fix-c23-extensions-v1-1-0833559418c7@kernel.org Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
2026-05-29drm/msm/dp: clear EDID on display unplugDmitry Baryshkov
Currently the driver only updates the EDID when it detects a connected monitor, which results in the connector still listing outdated modes even after the display is unplugged. Set connector's EDID to NULL on unplug to clear the list of modes. Tested-by: Val Packett <val@packett.cool> # x1e80100-dell-latitude-7455 Tested-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com> # Hamoa IOT EVK, QCS8300 Ride Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Patchwork: https://patchwork.freedesktop.org/patch/727619/ Link: https://lore.kernel.org/r/20260524-hpd-refactor-v6-10-cf3ab488dd7b@oss.qualcomm.com
2026-05-29drm/msm/dp: turn link_ready into pluggedDmitry Baryshkov
Tracking when the DP link is ready isn't that useful from the driver point of view. It doesn't provide a direct information if the device should be suspended, etc. Replace it with the 'plugged' boolean, which is set when the driver knows that there is DPRX plugged. Tested-by: Val Packett <val@packett.cool> # x1e80100-dell-latitude-7455 Tested-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com> # Hamoa IOT EVK, QCS8300 Ride Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Patchwork: https://patchwork.freedesktop.org/patch/727614/ Link: https://lore.kernel.org/r/20260524-hpd-refactor-v6-9-cf3ab488dd7b@oss.qualcomm.com
2026-05-29drm/msm/dp: Add sink_count to debug logsJessica Zhang
Add sink count to the debug logs for [un]plug and HPD IRQ handling. Signed-off-by: Jessica Zhang <jessica.zhang@oss.qualcomm.com> [DB: dropped link_ready handling] Tested-by: Val Packett <val@packett.cool> # x1e80100-dell-latitude-7455 Tested-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com> # Hamoa IOT EVK, QCS8300 Ride Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Patchwork: https://patchwork.freedesktop.org/patch/727620/ Link: https://lore.kernel.org/r/20260524-hpd-refactor-v6-8-cf3ab488dd7b@oss.qualcomm.com
2026-05-29drm/msm/dp: rework HPD handlingJessica Zhang
Handling of the HPD events in the MSM DP driver is plagued with lots of problems. It tries to work aside of the main DRM framework, handling the HPD signals on its own. There are two separate paths, one for the HPD signals coming from the DP HPD pin and another path for signals coming from outside (e.g. from the Type-C AltMode). It lies about the connected state, returning the link established state instead. It is not easy to understand or modify it. Having a separate event machine doesn't add extra clarity. Drop the whole event machine. When the DP receives a HPD event, send it to the DRM core. Then handle the events in the hpd_notify callback, unifying paths for HPD signals. Signed-off-by: Jessica Zhang <jessica.zhang@oss.qualcomm.com> Tested-by: Val Packett <val@packett.cool> # x1e80100-dell-latitude-7455 Tested-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com> # Hamoa IOT EVK, QCS8300 Ride Co-developed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Patchwork: https://patchwork.freedesktop.org/patch/727616/ Link: https://lore.kernel.org/r/20260524-hpd-refactor-v6-7-cf3ab488dd7b@oss.qualcomm.com
2026-05-29drm/msm/dp: drop event dataDmitry Baryshkov
With EV_USER_NOTIFICATION gone event's data is no longer useful. Drop it, removing also the argument from event handlers. Reviewed-by: Bjorn Andersson <andersson@kernel.org> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Tested-by: Val Packett <val@packett.cool> # x1e80100-dell-latitude-7455 Tested-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com> # Hamoa IOT EVK, QCS8300 Ride Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Patchwork: https://patchwork.freedesktop.org/patch/727610/ Link: https://lore.kernel.org/r/20260524-hpd-refactor-v6-6-cf3ab488dd7b@oss.qualcomm.com
2026-05-29drm/msm/dp: Drop EV_USER_NOTIFICATIONJessica Zhang
Currently, we queue an event for signalling HPD connect/disconnect. This can mean a delay in plug/unplug handling and notifying DRM core when a hotplug happens. Drop EV_USER_NOTIFICATION and signal the IRQ event as part of hotplug handling. Signed-off-by: Jessica Zhang <jessica.zhang@oss.qualcomm.com> Reviewed-by: Bjorn Andersson <andersson@kernel.org> Acked-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Tested-by: Val Packett <val@packett.cool> # x1e80100-dell-latitude-7455 Tested-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com> # Hamoa IOT EVK, QCS8300 Ride Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Patchwork: https://patchwork.freedesktop.org/patch/727607/ Link: https://lore.kernel.org/r/20260524-hpd-refactor-v6-5-cf3ab488dd7b@oss.qualcomm.com
2026-05-29drm/msm/dp: Move link training to atomic_enable()Jessica Zhang
Currently, the DP link training is being done during HPD. Move link training to atomic_enable() in accordance with the atomic_enable() documentation. Link disabling is already done in atomic_post_disable() (as part of the dp_ctrl_off_link_stream() helper). Signed-off-by: Jessica Zhang <jessica.zhang@oss.qualcomm.com> Tested-by: Val Packett <val@packett.cool> # x1e80100-dell-latitude-7455 Tested-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com> # Hamoa IOT EVK, QCS8300 Ride Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Acked-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Patchwork: https://patchwork.freedesktop.org/patch/727606/ Link: https://lore.kernel.org/r/20260524-hpd-refactor-v6-4-cf3ab488dd7b@oss.qualcomm.com
2026-05-29drm/msm/dp: Read DPCD and sink count in bridge detect()Jessica Zhang
Instead of relying on the link_ready flag to specify if DP is connected, read the DPCD bits and get the sink count to accurately detect if DP is connected. Signed-off-by: Jessica Zhang <jessica.zhang@oss.qualcomm.com> Tested-by: Val Packett <val@packett.cool> # x1e80100-dell-latitude-7455 Tested-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com> # Hamoa IOT EVK, QCS8300 Ride Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Patchwork: https://patchwork.freedesktop.org/patch/727603/ Link: https://lore.kernel.org/r/20260524-hpd-refactor-v6-3-cf3ab488dd7b@oss.qualcomm.com
2026-05-29drm/msm/dp: Fix the ISR_* enum valuesJessica Zhang
The ISR_HPD_* enum should represent values that can be read from the REG_DP_DP_HPD_INT_STATUS register. Swap ISR_HPD_IO_GLITCH_COUNT and ISR_HPD_REPLUG_COUNT to map them correctly to register values. While we are at it, correct the spelling for ISR_HPD_REPLUG_COUNT. Fixes: 8ede2ecc3e5e ("drm/msm/dp: Add DP compliance tests on Snapdragon Chipsets") Signed-off-by: Jessica Zhang <jessica.zhang@oss.qualcomm.com> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Tested-by: Val Packett <val@packett.cool> # x1e80100-dell-latitude-7455 Tested-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com> # Hamoa IOT EVK, QCS8300 Ride Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Patchwork: https://patchwork.freedesktop.org/patch/727602/ Link: https://lore.kernel.org/r/20260524-hpd-refactor-v6-2-cf3ab488dd7b@oss.qualcomm.com
2026-05-29drm/msm/dp: fix HPD state status bit shift valueJessica Zhang
The HPD state status is the 3 most significant bits, not 4 bits of the HPD_INT_STATUS register. Fix the bit shift macro so that the correct bits are returned in msm_dp_aux_is_link_connected(). Fixes: 19e52bcb27c2 ("drm/msm/dp: return correct connection status after suspend") Signed-off-by: Jessica Zhang <jessica.zhang@oss.qualcomm.com> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Tested-by: Val Packett <val@packett.cool> # x1e80100-dell-latitude-7455 Tested-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com> # Hamoa IOT EVK, QCS8300 Ride Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Patchwork: https://patchwork.freedesktop.org/patch/727611/ Link: https://lore.kernel.org/r/20260524-hpd-refactor-v6-1-cf3ab488dd7b@oss.qualcomm.com
2026-05-29gpu/buddy: Track per-order used blocks with a scoreboardFrancois Dugast
Extend the scoreboard approach from the previous commit to used blocks, so drm_buddy_print() can report per-order allocation pressure in O(1). Unlike free blocks, an allocated block can leave the allocated state through mark_free() (normal free and gpu_buddy_block_trim()) or be consumed directly by gpu_block_free() during coalescing. Both sites are guarded by gpu_buddy_block_is_allocated() and paired with the increment in mark_allocated(). v3: - Assert scoreboard is empty at fini(), as sanity check (Matthew Auld) v2: - Update after fix for use-after-free in split_block() call sites - Change goto label to out_free_used_scoreboard for clarity - Make drm_buddy_print() and gpu_buddy_print() symmetric for used and free Assisted-by: GitHub Copilot:claude-sonnet-4.6 Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://lore.kernel.org/r/20260522092600.32818-6-francois.dugast@intel.com Signed-off-by: Francois Dugast <francois.dugast@intel.com>
2026-05-29gpu/buddy: Track per-order free blocks with a scoreboardFrancois Dugast
Reporting per-order free block counts in drm_buddy_print() currently requires walking all rbtrees, which is O(n) over the total number of free blocks and holds the allocator lock for the duration. This becomes expensive on large VRAM heaps with many small free fragments. Maintain a free_scoreboard[] array indexed by order instead, so that the count for any order is always available in O(1). The scoreboard is kept accurate by hooking into the four places where a block's free state changes: mark_free(), mark_allocated(), mark_split(), and the sites in __gpu_buddy_free(), __force_merge(), and the four err_undo paths that call rbtree_remove() directly on free blocks without going through mark_*(). The print functions are simplified as a result: the rbtree traversal is replaced by a direct array lookup. v3: Update after introducing __gpu_buddy_undo_splits() helper v2: Update after fix for use-after-free in split_block() call sites Assisted-by: GitHub Copilot:claude-sonnet-4.6 Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://lore.kernel.org/r/20260522092600.32818-5-francois.dugast@intel.com Signed-off-by: Francois Dugast <francois.dugast@intel.com>
2026-05-29gpu/buddy: Introduce __gpu_buddy_undo_splits() helperFrancois Dugast
The pattern of merging a block back with its buddy on error paths is duplicated across multiple locations. Extract it into a __gpu_buddy_undo_splits() helper to avoid repetition and prepare for future changes. Suggested-by: Matthew Auld <matthew.auld@intel.com> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://lore.kernel.org/r/20260522092600.32818-4-francois.dugast@intel.com Signed-off-by: Francois Dugast <francois.dugast@intel.com>
2026-05-29gpu/buddy: Remove redundant condition in alloc_from_freetree() error pathFrancois Dugast
The err_undo label in alloc_from_freetree() is only reachable via a goto from inside the `while (tmp != order)` loop, which means tmp is guaranteed to differ from order at that point. The surrounding `if (tmp != order)` guard was therefore always true and can be dropped without any behavioral change. Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://lore.kernel.org/r/20260522092600.32818-3-francois.dugast@intel.com Signed-off-by: Francois Dugast <francois.dugast@intel.com>
2026-05-29gpu/buddy: Fix use-after-free in split_block() call sitesFrancois Dugast
When split_block() fails it returns before calling mark_split(), leaving the block in the FREE state and still linked in the rbtree. The four err_undo paths then call __gpu_buddy_free() without first removing the block from the tree, which leads to two distinct bugs: - If the buddy is also free, __gpu_buddy_free() merges the two siblings by calling gpu_block_free(mm, block) while block->rb is still linked in the tree. Any subsequent rbtree traversal will follow the now- dangling pointer, causing a use-after-free. - In alloc_from_freetree(), where there is no buddy guard, __gpu_buddy_free() always reaches mark_free() -> rbtree_insert() with block still in the tree, corrupting the rbtree. The same pattern is already used correctly in __force_merge(): call rbtree_remove() to unlink the block before handing it to __gpu_buddy_free(). Apply the same fix to all four err_undo sites. Reported-by: Sashiko <sashiko-bot@kernel.org> Assisted-by: GitHub Copilot:claude-sonnet-4.6 Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://lore.kernel.org/r/20260522092600.32818-2-francois.dugast@intel.com Signed-off-by: Francois Dugast <francois.dugast@intel.com>
2026-05-29Revert "media: renesas: vsp1: brx: Fix format propagation"Laurent Pinchart
This reverts commit 937f3e6b51f1cea079be9ba642665f2bf8bcc31f. The change to format propagation in the BRx broke configuration of the DRM pipeline. Revert it to fix the regression. The original commit was meant to fix a v4l2-compliance failure, with no known userspace applications being affected beside test tools. Reverting is the simplest option, a more comprehensive fix can be developed (and tested more thoroughly) later. Reported-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Closes: https://lore.kernel.org/linux-media/CA+V-a8t481xuwava0nb7uY9CUPqFWZ_8EP0xrK3BgumP7HDcLg@mail.gmail.com Fixes: 937f3e6b51f1 ("media: renesas: vsp1: brx: Fix format propagation") Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # On RZ/T2H Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Link: https://patch.msgid.link/20260506215650.1897177-3-laurent.pinchart+renesas@ideasonboard.com Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
2026-05-29Revert "media: renesas: vsp1: Initialize format on all pads"Laurent Pinchart
This reverts commit 133ac42af0a1b389e8b7b3dc7c1cc8c30ff162b6. The change to format initialization, along with the change to format propagation in the BRx in commit 937f3e6b51f1 ("media: renesas: vsp1: brx: Fix format propagation"), broke configuration of the DRM pipeline. Revert it to fix the regression. The original commit was meant to fix a v4l2-compliance failure, with no known userspace applications being affected beside test tools. Reverting is the simplest option, a more comprehensive fix can be developed (and tested more thoroughly) later. Fixes: 133ac42af0a1 ("media: renesas: vsp1: Initialize format on all pads") Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> # On RZ/T2H Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com> Link: https://patch.msgid.link/20260506215650.1897177-2-laurent.pinchart+renesas@ideasonboard.com Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
2026-05-29drm/hyperv: Use "hv_drm_" as symbol name prefixMichael Kelley
Function and structure names in the Hyper-V DRM driver currently use "hyperv_" as the prefix. This conflicts with usage in core Hyper-V and VMBus code, and incorrectly implies that functions and structures in this driver apply generically to Hyper-V. A specific conflict arises for "hyperv_init", which is an initcall for generic Hyper-V initialization on arm64. The conflict prevents the use of initcall_blacklist on the kernel boot line to skip loading this driver. Fix this by substituting "hv_drm_" as the prefix for all functions and structures in this driver. In most places, this is replacing "hyperv_" with "hv_drm_". In a few places, the substitution results in "hv_drm_drm_", which has been collapsed to just "hv_drm_". In two cases, the existing prefix is a bare "hv" (including in the to_hv() macro), which has been replaced with "hv_drm" for consistency. The changes are all mechanical text substitution in symbol names. There are no other code or functional changes. Signed-off-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Dexuan Cui <decui@microsoft.com> Signed-off-by: Hamza Mahfooz <someguy@effective-light.com> Link: https://patchwork.freedesktop.org/patch/msgid/20260529014826.41256-1-mhklkml@zohomail.com
2026-05-29drm/virtio: Add PM notifier to restore objects after hibernationDongwon Kim
Register a PM notifier in virtio-gpu to handle suspend/hibernate events. On PM_POST_HIBERNATION, restore all GPU objects so that the driver can properly recover after resume. Suggested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Cc: Vivek Kasireddy <vivek.kasireddy@intel.com> Signed-off-by: Dongwon Kim <dongwon.kim@intel.com> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Link: https://patch.msgid.link/20260526192814.179673-4-dongwon.kim@intel.com [dmitry.osipenko@collabora.com: rename vgdev->hibernation -> hibernated] [dmitry.osipenko@collabora.com: restore objs on suspend error] [dmitry.osipenko@collabora.com: no_cb int -> bool] [dmitry.osipenko@collabora.com: don't include pm_runtime.h] [dmitry.osipenko@collabora.com: proeprly handle failing register_pm_notifier]