kernel/linux.git/include/linux/device.h, branch v6.12.80

driver core: generalize driver_override in struct device

2026-04-02T11:09:25+00:00

[ Upstream commit cb3d1049f4ea77d5ad93f17d8ac1f2ed4da70501 ] Currently, there are 12 busses (including platform and PCI) that duplicate the driver_override logic for their individual devices. All of them seem to be prone to the bug described in [1]. While this could be solved for every bus individually using a separate lock, solving this in the driver-core generically results in less (and cleaner) changes overall. Thus, move driver_override to struct device, provide corresponding accessors for busses and handle locking with a separate lock internally. In particular, add device_set_driver_override(), device_has_driver_override(), device_match_driver_override() and generalize the sysfs store() and show() callbacks via a driver_override feature flag in struct bus_type. Until all busses have migrated, keep driver_set_override() in place. Note that we can't use the device lock for the reasons described in [2]. Link: https://bugzilla.kernel.org/show_bug.cgi?id=220789 [1] Link: https://lore.kernel.org/driver-core/DGRGTIRHA62X.3RY09D9SOK77P@kernel.org/ [2] Tested-by: Gui-Dong Han Co-developed-by: Gui-Dong Han Signed-off-by: Gui-Dong Han Reviewed-by: Greg Kroah-Hartman Link: https://patch.msgid.link/20260303115720.48783-2-dakr@kernel.org [ Use dev->bus instead of sp->bus for consistency; fix commit message to refer to the struct bus_type's driver_override feature flag. - Danilo ] Signed-off-by: Danilo Krummrich Stable-dep-of: 2b38efc05bf7 ("driver core: platform: use generic driver_override infrastructure") Signed-off-by: Sasha Levin

driver core/PM: Set power.no_callbacks along with power.no_pm

2025-10-12T10:57:19+00:00

commit c2ce2453413d429e302659abc5ace634e873f6f5 upstream. Devices with power.no_pm set are not expected to need any power management at all, so modify device_set_pm_not_required() to set power.no_callbacks for them too in case runtime PM will be enabled for any of them (which in principle may be done for convenience if such a device participates in a dependency chain). Since device_set_pm_not_required() must be called before device_add() or it would not have any effect, it can update power.no_callbacks without locking, unlike pm_runtime_no_callbacks() that can be called after registering the target device. Signed-off-by: Rafael J. Wysocki Cc: stable Reviewed-by: Sudeep Holla Link: https://lore.kernel.org/r/1950054.tdWV9SEqCh@rafael.j.wysocki Signed-off-by: Greg Kroah-Hartman

driver core: Split devres APIs to device/devres.h

2025-05-29T09:03:15+00:00

[ Upstream commit a21cad9312767d26b5257ce0662699bb202cdda1 ] device.h is a huge header which is hard to follow and easy to miss something. Improve that by splitting devres APIs to device/devres.h. In particular this helps to speedup the build of the code that includes device.h solely for a devres APIs. While at it, cast the error pointers to __iomem using IOMEM_ERR_PTR() and fix sparse warnings. Signed-off-by: Raag Jadav Acked-by: Arnd Bergmann Reviewed-by: Greg Kroah-Hartman Signed-off-by: Andy Shevchenko Stable-dep-of: 7dd7f39fce00 ("ASoC: SOF: Intel: hda: Fix UAF when reloading module") Signed-off-by: Sasha Levin

cxl/port: Fix use-after-free, permit out-of-order decoder shutdown

2024-10-25T21:07:03+00:00

In support of investigating an initialization failure report [1], cxl_test was updated to register mock memory-devices after the mock root-port/bus device had been registered. That led to cxl_test crashing with a use-after-free bug with the following signature: cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem0:decoder7.0 @ 0 next: cxl_switch_uport.0 nr_eps: 1 nr_targets: 1 cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem4:decoder14.0 @ 1 next: cxl_switch_uport.0 nr_eps: 2 nr_targets: 1 cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[0] = cxl_switch_dport.0 for mem0:decoder7.0 @ 0 1) cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[1] = cxl_switch_dport.4 for mem4:decoder14.0 @ 1 [..] cxld_unregister: cxl decoder14.0: cxl_region_decode_reset: cxl_region region3: mock_decoder_reset: cxl_port port3: decoder3.0 reset 2) mock_decoder_reset: cxl_port port3: decoder3.0: out of order reset, expected decoder3.1 cxl_endpoint_decoder_release: cxl decoder14.0: [..] cxld_unregister: cxl decoder7.0: 3) cxl_region_decode_reset: cxl_region region3: Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bc3: 0000 [#1] PREEMPT SMP PTI [..] RIP: 0010:to_cxl_port+0x8/0x60 [cxl_core] [..] Call Trace: cxl_region_decode_reset+0x69/0x190 [cxl_core] cxl_region_detach+0xe8/0x210 [cxl_core] cxl_decoder_kill_region+0x27/0x40 [cxl_core] cxld_unregister+0x5d/0x60 [cxl_core] At 1) a region has been established with 2 endpoint decoders (7.0 and 14.0). Those endpoints share a common switch-decoder in the topology (3.0). At teardown, 2), decoder14.0 is the first to be removed and hits the "out of order reset case" in the switch decoder. The effect though is that region3 cleanup is aborted leaving it in-tact and referencing decoder14.0. At 3) the second attempt to teardown region3 trips over the stale decoder14.0 object which has long since been deleted. The fix here is to recognize that the CXL specification places no mandate on in-order shutdown of switch-decoders, the driver enforces in-order allocation, and hardware enforces in-order commit. So, rather than fail and leave objects dangling, always remove them. In support of making cxl_region_decode_reset() always succeed, cxl_region_invalidate_memregion() failures are turned into warnings. Crashing the kernel is ok there since system integrity is at risk if caches cannot be managed around physical address mutation events like CXL region destruction. A new device_for_each_child_reverse_from() is added to cleanup port->commit_end after all dependent decoders have been disabled. In other words if decoders are allocated 0->1->2 and disabled 1->2->0 then port->commit_end only decrements from 2 after 2 has been disabled, and it decrements all the way to zero since 1 was disabled previously. Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net [1] Cc: stable@vger.kernel.org Fixes: 176baefb2eb5 ("cxl/hdm: Commit decoder state to hardware") Reviewed-by: Jonathan Cameron Cc: Greg Kroah-Hartman Cc: Davidlohr Bueso Cc: Dave Jiang Cc: Alison Schofield Cc: Ira Weiny Cc: Zijun Hu Signed-off-by: Dan Williams Reviewed-by: Ira Weiny Link: https://patch.msgid.link/172964782781.81806.17902885593105284330.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Ira Weiny

dma-mapping: clearly mark DMA ops as an architecture feature

2024-09-04T04:08:51+00:00

DMA ops are a helper for architectures and not for drivers to override the DMA implementation. Unfortunately driver authors keep ignoring this. Make the fact more clear by renaming the symbol to ARCH_HAS_DMA_OPS and having the two drivers overriding their dma_ops depend on that. These drivers should probably be marked broken, but we can give them a bit of a grace period for that. Signed-off-by: Christoph Hellwig Reviewed-by: Thomas Gleixner Acked-by: Sakari Ailus # for IPU6 Acked-by: Robin Murphy

dma-mapping: direct calls for dma-iommu

2024-08-22T04:18:11+00:00

Directly call into dma-iommu just like we have been doing for dma-direct for a while. This avoids the indirect call overhead for IOMMU ops and removes the need to have DMA ops entirely for many common configurations. Signed-off-by: Leon Romanovsky Signed-off-by: Leon Romanovsky Acked-by: Greg Kroah-Hartman Acked-by: Robin Murphy Signed-off-by: Christoph Hellwig

driver core: make [device_]driver_attach take a const *

2024-06-20T10:51:42+00:00

Change device_driver_attach() and driver_attach() to take a const * to struct device driver as neither of them modify the structure at all. Also, for some odd reason, drivers/dma/idxd/compat.c had a duplicate external reference to device_driver_attach(), so remove that to fix up the build, it should never have had that there in the first place. Cc: Rafael J. Wysocki Cc: Fenghua Yu Cc: Dave Jiang Cc: Vinod Koul Cc: Andy Shevchenko Cc: Petr Tesarik Cc: Alexander Lobakin Cc: dmaengine@vger.kernel.org Link: https://lore.kernel.org/r/2024061401-rasping-manger-c385@gregkh Signed-off-by: Greg Kroah-Hartman

Merge tag 'v6.10-rc4' into driver-core-next

2024-06-17T06:33:41+00:00

We need the driver core and sysfs fixes in here to build on top of. Signed-off-by: Greg Kroah-Hartman

driver core: device.h: Group of_node handling declarations and definitions

2024-06-04T16:04:36+00:00

There are a few of_node related APIs defined in the driver core. Group the respective declarations and definitions in the header. There is no functional change. Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20240531145129.1506733-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman

driver core: remove devm_device_add_groups()

2024-06-04T13:53:36+00:00

There is no more in-kernel users of this function, and no driver should ever be using it, so remove it from the kernel. Acked-by: Dmitry Torokhov Acked-by: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230704131715.44454-8-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman