kernel/linux.git/drivers/base/base.h, branch v6.1.168

driver core: remove make_class_name declaration

2022-09-09T08:49:54+00:00

make_class_name has been removed since commit 39aba963d937 ("driver core: remove CONFIG_SYSFS_DEPRECATED_V2 but keep it for block devices"), so remove it. Signed-off-by: Gaosheng Cui Link: https://lore.kernel.org/r/20220909063337.1146151-1-cuigaosheng1@huawei.com Signed-off-by: Greg Kroah-Hartman

driver core: Add wait_for_init_devices_probe helper function

2022-06-10T13:57:54+00:00

Some devices might need to be probed and bound successfully before the kernel boot sequence can finish and move on to init/userspace. For example, a network interface might need to be bound to be able to mount a NFS rootfs. With fw_devlink=on by default, some of these devices might be blocked from probing because they are waiting on a optional supplier that doesn't have a driver. While fw_devlink will eventually identify such devices and unblock the probing automatically, it might be too late by the time it unblocks the probing of devices. For example, the IP4 autoconfig might timeout before fw_devlink unblocks probing of the network interface. This function is available to temporarily try and probe all devices that have a driver even if some of their suppliers haven't been added or don't have drivers. The drivers can then decide which of the suppliers are optional vs mandatory and probe the device if possible. By the time this function returns, all such "best effort" probes are guaranteed to be completed. If a device successfully probes in this mode, we delete all fw_devlink discovered dependencies of that device where the supplier hasn't yet probed successfully because they have to be optional dependencies. This also means that some devices that aren't needed for init and could have waited for their optional supplier to probe (when the supplier's module is loaded later on) would end up probing prematurely with limited functionality. So call this function only when boot would fail without it. Tested-by: Geert Uytterhoeven Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20220601070707.3946847-5-saravanak@google.com Signed-off-by: Greg Kroah-Hartman

driver core: Extend deferred probe timeout on driver registration

2022-05-19T17:32:33+00:00

The deferred probe timer that's used for this currently starts at late_initcall and runs for driver_deferred_probe_timeout seconds. The assumption being that all available drivers would be loaded and registered before the timer expires. This means, the driver_deferred_probe_timeout has to be pretty large for it to cover the worst case. But if we set the default value for it to cover the worst case, it would significantly slow down the average case. For this reason, the default value is set to 0. Also, with CONFIG_MODULES=y and the current default values of driver_deferred_probe_timeout=0 and fw_devlink=on, devices with missing drivers will cause their consumer devices to always defer their probes. This is because device links created by fw_devlink defer the probe even before the consumer driver's probe() is called. Instead of a fixed timeout, if we extend an unexpired deferred probe timer on every successful driver registration, with the expectation more modules would be loaded in the near future, then the default value of driver_deferred_probe_timeout only needs to be as long as the worst case time difference between two consecutive module loads. So let's implement that and set the default value to 10 seconds when CONFIG_MODULES=y. Cc: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" Cc: Rob Herring Cc: Linus Walleij Cc: Will Deacon Cc: Ulf Hansson Cc: Kevin Hilman Cc: Thierry Reding Cc: Mark Brown Cc: Pavel Machek Cc: Geert Uytterhoeven Cc: Yoshihiro Shimoda Cc: Paul Kocialkowski Cc: linux-gpio@vger.kernel.org Cc: linux-pm@vger.kernel.org Cc: iommu@lists.linux-foundation.org Reviewed-by: Mark Brown Acked-by: Rob Herring Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20220429220933.1350374-1-saravanak@google.com Signed-off-by: Greg Kroah-Hartman

software nodes: Split software_node_notify()

2021-07-16T17:17:05+00:00

Split software_node_notify_remove) out of software_node_notify() and make device_platform_notify() call the latter on device addition and the former on device removal. While at it, put the headers of the above functions into base.h, because they don't need to be present in a global header file. No intentional functional impact. Signed-off-by: Rafael J. Wysocki Reviewed-by: Greg Kroah-Hartman Reviewed-by: Heikki Krogerus Reviewed-by: Andy Shevchenko

driver core: Export device_driver_attach()

2021-06-21T21:29:24+00:00

This is intended as a replacement API for device_bind_driver(). It has at least the following benefits: - Internal locking. Few of the users of device_bind_driver() follow the locking rules - Calls device driver probe() internally. Notably this means that devm support for probe works correctly as probe() error will call devres_release_all() - struct device_driver -> dev_groups is supported - Simplified calling convention, no need to manually call probe(). The general usage is for situations that already know what driver to bind and need to ensure the bind is synchronized with other logic. Call device_driver_attach() after device_add(). If probe() returns a failure then this will be preserved up through to the error return of device_driver_attach(). Signed-off-by: Jason Gunthorpe Signed-off-by: Christoph Hellwig Reviewed-by: Cornelia Huck Reviewed-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20210617142218.1877096-6-hch@lst.de Signed-off-by: Alex Williamson

driver core: Improve fw_devlink & deferred_probe_timeout interaction

2021-04-05T07:17:56+00:00

deferred_probe_timeout kernel commandline parameter allows probing of consumer devices if the supplier devices don't have any drivers. fw_devlink=on will indefintely block probe() calls on a device if all its suppliers haven't probed successfully. This completely skips calls to driver_deferred_probe_check_state() since that's only called when a .probe() function calls framework APIs. So fw_devlink=on breaks deferred_probe_timeout. deferred_probe_timeout in its current state also ignores a lot of information that's now available to the kernel. It assumes all suppliers that haven't probed when the timer expires (or when initcalls are done on a static kernel) will never probe and fails any calls to acquire resources from these unprobed suppliers. However, this assumption by deferred_probe_timeout isn't true under many conditions. For example: - If the consumer happens to be before the supplier in the deferred probe list. - If the supplier itself is waiting on its supplier to probe. This patch fixes both these issues by relaxing device links between devices only if the supplier doesn't have any driver that could match with (NOT bound to) the supplier device. This way, we only fail attempts to acquire resources from suppliers that truly don't have any driver vs suppliers that just happen to not have probed yet. Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20210402040342.2944858-3-saravanak@google.com Signed-off-by: Greg Kroah-Hartman

driver core: Update device link status properly for device_bind_driver()

2021-03-23T13:58:11+00:00

Device link status was not getting updated correctly when device_bind_driver() is called on a device. This causes a warning[1]. Fix this by updating device links that can be updated and dropping device links that can't be updated to a sensible state. [1] - https://lore.kernel.org/lkml/56f7d032-ba5a-a8c7-23de-2969d98c527e@nvidia.com/ Tested-by: Jon Hunter Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20210302211133.2244281-3-saravanak@google.com Signed-off-by: Greg Kroah-Hartman

driver core: auxiliary bus: Fix calling stage for auxiliary bus init

2021-02-11T07:43:03+00:00

When the auxiliary device code is built into the kernel, it can be executed before the auxiliary bus is registered. This causes bus->p to be not allocated and triggers a NULL pointer dereference when the auxiliary bus device gets added with bus_add_device(). Call the auxiliary_bus_init() under driver_init() so the bus is initialized before devices. Below is the kernel splat for the bug: [ 1.948215] BUG: kernel NULL pointer dereference, address: 0000000000000060 [ 1.950670] #PF: supervisor read access in kernel mode [ 1.950670] #PF: error_code(0x0000) - not-present page [ 1.950670] PGD 0 [ 1.950670] Oops: 0000 1 SMP NOPTI [ 1.950670] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.10.0-intel-nextsvmtest+ #2205 [ 1.950670] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [ 1.950670] RIP: 0010:bus_add_device+0x64/0x140 [ 1.950670] Code: 00 49 8b 75 20 48 89 df e8 59 a1 ff ff 41 89 c4 85 c0 75 7b 48 8b 53 50 48 85 d2 75 03 48 8b 13 49 8b 85 a0 00 00 00 48 89 de <48> 8 78 60 48 83 c7 18 e8 ef d9 a9 ff 41 89 c4 85 c0 75 45 48 8b [ 1.950670] RSP: 0000:ff46032ac001baf8 EFLAGS: 00010246 [ 1.950670] RAX: 0000000000000000 RBX: ff4597f7414aa680 RCX: 0000000000000000 [ 1.950670] RDX: ff4597f74142bbc0 RSI: ff4597f7414aa680 RDI: ff4597f7414aa680 [ 1.950670] RBP: ff46032ac001bb10 R08: 0000000000000044 R09: 0000000000000228 [ 1.950670] R10: ff4597f741141b30 R11: ff4597f740182a90 R12: 0000000000000000 [ 1.950670] R13: ffffffffa5e936c0 R14: 0000000000000000 R15: 0000000000000000 [ 1.950670] FS: 0000000000000000(0000) GS:ff4597f7bba00000(0000) knlGS:0000000000000000 [ 1.950670] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.950670] CR2: 0000000000000060 CR3: 000000002140c001 CR4: 0000000000f71ef0 [ 1.950670] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1.950670] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 [ 1.950670] PKRU: 55555554 [ 1.950670] Call Trace: [ 1.950670] device_add+0x3ee/0x850 [ 1.950670] __auxiliary_device_add+0x47/0x60 [ 1.950670] idxd_pci_probe+0xf77/0x1180 [ 1.950670] local_pci_probe+0x4a/0x90 [ 1.950670] pci_device_probe+0xff/0x1b0 [ 1.950670] really_probe+0x1cf/0x440 [ 1.950670] ? rdinit_setup+0x31/0x31 [ 1.950670] driver_probe_device+0xe8/0x150 [ 1.950670] device_driver_attach+0x58/0x60 [ 1.950670] __driver_attach+0x8f/0x150 [ 1.950670] ? device_driver_attach+0x60/0x60 [ 1.950670] ? device_driver_attach+0x60/0x60 [ 1.950670] bus_for_each_dev+0x79/0xc0 [ 1.950670] ? kmem_cache_alloc_trace+0x323/0x430 [ 1.950670] driver_attach+0x1e/0x20 [ 1.950670] bus_add_driver+0x154/0x1f0 [ 1.950670] driver_register+0x70/0xc0 [ 1.950670] __pci_register_driver+0x54/0x60 [ 1.950670] idxd_init_module+0xe2/0xfc [ 1.950670] ? idma64_platform_driver_init+0x19/0x19 [ 1.950670] do_one_initcall+0x4a/0x1e0 [ 1.950670] kernel_init_freeable+0x1fc/0x25c [ 1.950670] ? rest_init+0xba/0xba [ 1.950670] kernel_init+0xe/0x116 [ 1.950670] ret_from_fork+0x1f/0x30 [ 1.950670] Modules linked in: [ 1.950670] CR2: 0000000000000060 [ 1.950670] --[ end trace cd7d1b226d3ca901 ]-- Fixes: 7de3697e9cbd ("Add auxiliary bus support") Reported-by: Jacob Pan Reviewed-by: Dan Williams Acked-by: Dave Ertman Signed-off-by: Dave Jiang Link: https://lore.kernel.org/r/20210210201611.1611074-1-dave.jiang@intel.com Cc: stable Signed-off-by: Greg Kroah-Hartman

driver core: make driver_probe_device() static

2020-12-09T18:30:44+00:00

It's only used inside drivers/base/dd.c Signed-off-by: Julian Wiedmann Link: https://lore.kernel.org/r/20201123111938.18968-1-jwi@linux.ibm.com Signed-off-by: Greg Kroah-Hartman

Revert "driver core: fw_devlink: Add support for batching fwnode parsing"

2020-12-09T18:10:20+00:00

This reverts commit 716a7a25969003d82ab738179c3f1068a120ed11. The fw_devlink_pause/resume() APIs added by the commit being reverted were a first cut attempt at optimizing boot time. But these APIs don't fully solve the problem and are very fragile (can only be used for the top level devices being added). This series replaces them with a much better optimization that works for all device additions and also has the benefit of reducing the complexity of the firmware (DT, EFI) specific code and abstracting out common code to driver core. Signed-off-by: Saravana Kannan Link: https://lore.kernel.org/r/20201121020232.908850-7-saravanak@google.com Signed-off-by: Greg Kroah-Hartman