kernel/linux.git/drivers/parport/share.c, branch v7.1

parport: Fix race between port and client registration

2026-05-22T10:19:02+00:00

The parport subsystem registers port devices before they are fully initialised, resulting in a race condition where client drivers such as lp can attach to ports that are not completely initialised or even being torn down. When the port and client drivers are built as modules and loaded around the same time during boot, this occasionally results in a crash. I was able to make this happen reliably in a VM with a PC-style parallel port by patching parport_pc to fail probing: > --- a/drivers/parport/parport_pc.c > +++ b/drivers/parport/parport_pc.c > @@ -2069,7 +2069,7 @@ static struct parport *__parport_pc_probe_port(unsigned long int base, > if (!p) > goto out3; > > - base_res = request_region(base, 3, p->name); > + base_res = NULL; > if (!base_res) > goto out4; > and then running: while true; do modprobe lp & modprobe parport_pc wait rmmod lp parport_pc done for a few seconds. In the long term I think port registration should be changed to put the call to device_add() inside parport_announce_port(), but since the latter currently cannot fail this will require changing all port drivers. For now, add a flag to indicate whether a port has been "announced" and only try to attach client drivers to ports when the flag is set. Fixes: 6fa45a226897 ("parport: add device-model to parport subsystem") Closes: https://bugs.debian.org/1130365 Closes: https://lore.kernel.org/all/6ba903ad-9897-42bb-8c2d-337385cc3746@molgen.mpg.de/ Cc: stable Signed-off-by: Ben Hutchings Acked-by: Sudip Mukherjee Link: https://patch.msgid.link/afo6uBv68GDevbMD@decadent.org.uk Signed-off-by: Greg Kroah-Hartman

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

Merge tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2024-07-25T17:42:22+00:00

Pull driver core updates from Greg KH: "Here is the big set of driver core changes for 6.11-rc1. Lots of stuff in here, with not a huge diffstat, but apis are evolving which required lots of files to be touched. Highlights of the changes in here are: - platform remove callback api final fixups (Uwe took many releases to get here, finally!) - Rust bindings for basic firmware apis and initial driver-core interactions. It's not all that useful for a "write a whole driver in rust" type of thing, but the firmware bindings do help out the phy rust drivers, and the driver core bindings give a solid base on which others can start their work. There is still a long way to go here before we have a multitude of rust drivers being added, but it's a great first step. - driver core const api changes. This reached across all bus types, and there are some fix-ups for some not-common bus types that linux-next and 0-day testing shook out. This work is being done to help make the rust bindings more safe, as well as the C code, moving toward the end-goal of allowing us to put driver structures into read-only memory. We aren't there yet, but are getting closer. - minor devres cleanups and fixes found by code inspection - arch_topology minor changes - other minor driver core cleanups All of these have been in linux-next for a very long time with no reported problems" * tag 'driver-core-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits) ARM: sa1100: make match function take a const pointer sysfs/cpu: Make crash_hotplug attribute world-readable dio: Have dio_bus_match() callback take a const * zorro: make match function take a const pointer driver core: module: make module_[add|remove]_driver take a const * driver core: make driver_find_device() take a const * driver core: make driver_[create|remove]_file take a const * firmware_loader: fix soundness issue in `request_internal` firmware_loader: annotate doctests as `no_run` devres: Correct code style for functions that return a pointer type devres: Initialize an uninitialized struct member devres: Fix memory leakage caused by driver API devm_free_percpu() devres: Fix devm_krealloc() wasting memory driver core: platform: Switch to use kmemdup_array() driver core: have match() callback in struct bus_type take a const * MAINTAINERS: add Rust device abstractions to DRIVER CORE device: rust: improve safety comments MAINTAINERS: add Danilo as FIRMWARE LOADER maintainer MAINTAINERS: add Rust FW abstractions to FIRMWARE LOADER firmware: rust: improve safety comments ...

parport: Remove 'drivers' list

2024-07-03T14:44:22+00:00

The list has been empty since: 'commit 3275158fa52a ("parport: remove use of devmodel")' This also means we can remove the 'list_head' from struct parport_driver. Signed-off-by: Dr. David Alan Gilbert Acked-by: Sudip Mukherjee Link: https://lore.kernel.org/r/20240502154823.67235-2-linux@treblig.org Signed-off-by: Greg Kroah-Hartman

parport: make parport_bus_type const

2024-06-18T14:05:14+00:00

Now that the driver core can properly handle constant struct bus_type, move the parport_bus_type variable to be a constant structure as well, placing it into read-only memory which can not be modified at runtime. Suggested-by: Greg Kroah-Hartman Signed-off-by: Ricardo B. Marliere Reviewed-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20240204-bus_cleanup-parport-v1-1-e6a0f756bbb8@marliere.net Signed-off-by: Greg Kroah-Hartman

parport: add missing MODULE_DESCRIPTION()

2024-06-04T15:39:56+00:00

make allmodconfig && make W=1 C=1 reports: WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/parport/parport.o Add the missing MODULE_DESCRIPTION() macro invocation. Signed-off-by: Jeff Johnson Link: https://lore.kernel.org/r/20240530-parport-v1-1-09bee2ca3123@quicinc.com Signed-off-by: Greg Kroah-Hartman

parport: Save a few bytes of memory

2023-12-07T02:09:31+00:00

Most of parport_register_dev_model() callers pass a 'name' that is a constant string. So kstrdup_const() can be used to save the duplication of this string when it is not needed. This saves a few bytes of memory. Use kfree_const() accordingly when this string is freed. Signed-off-by: Christophe JAILLET Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/0eba5f2ddd142ab0f577f67e482d1152b40ee720.1700860416.git.christophe.jaillet@wanadoo.fr Signed-off-by: Greg Kroah-Hartman

parport: Drop even more unneeded NULL or 0 assignments

2023-10-21T21:04:23+00:00

kzalloc() gives us a zeroed memory, no need to explicitly assing 0 or NULL or similar to the members of the data structure that has been allocated with the above mentioned API. Note, the initializstion of full_list member is not needed anymore as list_add_tail will rewrite the contents of the prev and next pointers. Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20231018145948.1367648-2-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman

parport: Clean up resources correctly when parport_register_port() fails

2023-10-21T21:04:23+00:00

The smatch warns about uncleaned resources in case the parport_register_port() fails: parport_register_port() warn: '&tmp->full_list' not removed from list This is indeed an issue introduced when converting code to use kasprintf(). However, the whole kasprintf() dance in this case is not needed as dev_set_name() can handle the formatted input and produces the same result. So, the solution is to delegate name forming to the dev_set_name() and make device_register() error path to deal with error handling (via put_device() call). Fixes: 8d8ae17eb0de ("parport: Use kasprintf() instead of fixed buffer formatting") Reported-by: kernel test robot Reported-by: Dan Carpenter Closes: https://lore.kernel.org/r/202310180809.hepZB9k6-lkp@intel.com/ Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20231018145948.1367648-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman