linux.git/drivers/firewire/core-device.c, branch v6.8-rc2

firewire: core: fill model field in modalias of unit device for legacy layout of configuration ROM

2024-01-10T09:37:13+00:00

As the last part of support for legacy layout of configuration ROM, this
commit traverses vendor directory as well as root directory when
constructing modalias for unit device. The change brings loss of backward
compatibility since it can fill model field ('mo') which is 0 at current
implementation in the case. However, we can be optimistic against
regression for unit drivers in kernel, due to some points:

1. ALSA drivers for audio and music units use the model fields to match
   device, however all of supported devices does not have such legacy
   layout.
2. the other unit drivers (e.g. sbp2) does not use the model field to
   match device.

The rest of concern is user space application. The most of applications
just take care of node device and does not use the modalias of unit
device, thus the change does not affect to them. But systemd project is
known to get affects from the change since it includes hwdb to take udev
to configure fw character device conveniently. I have a plan to work for
systemd so that the access permission of character device could be kept
across the change.

Suggested-by: Adam Goldman 
Link: https://lore.kernel.org/r/20231221134849.603857-9-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto

firewire: core: detect model name for legacy layout of configuration ROM

2024-01-08T00:36:56+00:00

As the part of support for legacy layout of configuration ROM, this
commit traverses vendor directory as well as root directory when showing
device attribute for node device. This change expects 'model_name'
attribute appears in node device, however it is probable to see the other
types of descriptor leaf if the vendor directory includes.

Suggested-by: Adam Goldman 
Link: https://lore.kernel.org/r/20231221134849.603857-8-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto

firewire: core: detect numeric model identifier for legacy layout of configuration ROM

2024-01-08T00:36:56+00:00

As the part of support for legacy layout of configuration ROM, this
commit traverses vendor directory as well as root directory when showing
device attribute for node device. This change expects 'model' attribute
appears in node device, however it is probable to see the other types of
immediate values if the vendor directory includes.

Suggested-by: Adam Goldman 
Link: https://lore.kernel.org/r/20231221134849.603857-7-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto

firewire: test: add KUnit test for device attributes

2024-01-08T00:36:56+00:00

The traverse over CSR space results in attributes of node and unit
devices. Any test of the traverse is useful.

This commit adds a skeleton of KUnit test for the purpose.

Link: https://lore.kernel.org/r/20231221134849.603857-4-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto

firewire: core: replace magic number with macro

2024-01-08T00:36:56+00:00

In IEEE 1394 specification, the size of bus information block of
configuration ROM is fixed to 5, thus the offset of root directory is 5.
Current implementation to handle device structures has the hard-coded
offset.

This commit replaces the offset with macro.

Link: https://lore.kernel.org/r/20231221134849.603857-3-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto

firewire: core: adds constant qualifier for local helper functions

2024-01-08T00:36:56+00:00

Some local functions just handles given argument as mutable, thus it is
preferable to add constant qualifier to them.

Link: https://lore.kernel.org/r/20231221134849.603857-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto

firewire: make fw_bus_type const

2024-01-08T00:36:55+00:00

Now that the driver core can properly handle constant struct bus_type,
move the fw_bus_type variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.

Cc: Takashi Sakamoto 
Cc: linux1394-devel@lists.sourceforge.net
Signed-off-by: Greg Kroah-Hartman 
Link: https://lore.kernel.org/r/2023121931-skydiver-dodgy-d1bd@gregkh
Signed-off-by: Takashi Sakamoto

firewire: core: fix possible memory leak in create_units()

2023-11-30T00:16:35+00:00

If device_register() fails, the refcount of device is not 0, the name
allocated in dev_set_name() is leaked. To fix this by calling put_device(),
so that it will be freed in callback function kobject_cleanup().

unreferenced object 0xffff9d99035c7a90 (size 8):
  comm "systemd-udevd", pid 168, jiffies 4294672386 (age 152.089s)
  hex dump (first 8 bytes):
    66 77 30 2e 30 00 ff ff                          fw0.0...
  backtrace:
    [<00000000e1d62bac>] __kmem_cache_alloc_node+0x1e9/0x360
    [<00000000bbeaff31>] __kmalloc_node_track_caller+0x44/0x1a0
    [<00000000491f2fb4>] kvasprintf+0x67/0xd0
    [<000000005b960ddc>] kobject_set_name_vargs+0x1e/0x90
    [<00000000427ac591>] dev_set_name+0x4e/0x70
    [<000000003b4e447d>] create_units+0xc5/0x110

fw_unit_release() will be called in the error path, move fw_device_get()
before calling device_register() to keep balanced with fw_device_put() in
fw_unit_release().

Cc: stable@vger.kernel.org
Fixes: 1fa5ae857bb1 ("driver core: get rid of struct device's bus_id string array")
Fixes: a1f64819fe9f ("firewire: struct device - replace bus_id with dev_name(), dev_set_name()")
Signed-off-by: Yang Yingliang 
Signed-off-by: Takashi Sakamoto

Revert "firewire: core: obsolete usage of GFP_ATOMIC at building node tree"

2023-09-15T09:37:52+00:00

This reverts commit 06f45435d985d60d7d2fe2424fbb9909d177a63d.

John Ogness reports the case that the allocation is in atomic context under
acquired spin-lock.

[   12.555784] BUG: sleeping function called from invalid context at include/linux/sched/mm.h:306
[   12.555808] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 70, name: kworker/1:2
[   12.555814] preempt_count: 1, expected: 0
[   12.555820] INFO: lockdep is turned off.
[   12.555824] irq event stamp: 208
[   12.555828] hardirqs last  enabled at (207): [] ._raw_spin_unlock_irq+0x44/0x80
[   12.555850] hardirqs last disabled at (208): [] .__schedule+0x854/0xfe0
[   12.555859] softirqs last  enabled at (188): [] .addrconf_verify_rtnl+0x2c4/0xb70
[   12.555872] softirqs last disabled at (182): [] .addrconf_verify_rtnl+0x70/0xb70
[   12.555884] CPU: 1 PID: 70 Comm: kworker/1:2 Tainted: G S                 6.6.0-rc1 #1
[   12.555893] Hardware name: PowerMac7,2 PPC970 0x390202 PowerMac
[   12.555898] Workqueue: firewire_ohci .bus_reset_work [firewire_ohci]
[   12.555939] Call Trace:
[   12.555944] [c000000009677830] [c0000000010d83c0] .dump_stack_lvl+0x8c/0xd0 (unreliable)
[   12.555963] [c0000000096778b0] [c000000000140270] .__might_resched+0x320/0x340
[   12.555978] [c000000009677940] [c000000000497600] .__kmem_cache_alloc_node+0x390/0x460
[   12.555993] [c000000009677a10] [c0000000003fe620] .__kmalloc+0x70/0x310
[   12.556007] [c000000009677ac0] [c0003d00004e2268] .fw_core_handle_bus_reset+0x2c8/0xba0 [firewire_core]
[   12.556060] [c000000009677c20] [c0003d0000491190] .bus_reset_work+0x330/0x9b0 [firewire_ohci]
[   12.556079] [c000000009677d10] [c00000000011d0d0] .process_one_work+0x280/0x6f0
[   12.556094] [c000000009677e10] [c00000000011d8a0] .worker_thread+0x360/0x500
[   12.556107] [c000000009677ef0] [c00000000012e3b4] .kthread+0x154/0x160
[   12.556120] [c000000009677f90] [c00000000000bfa8] .start_kernel_thread+0x10/0x14

Cc: stable@kernel.org
Reported-by: John Ogness 
Link: https://lore.kernel.org/lkml/87jzsuv1xk.fsf@jogness.linutronix.de/raw
Signed-off-by: Takashi Sakamoto

firewire: core: obsolete usage of GFP_ATOMIC at building node tree

2023-06-05T22:54:52+00:00

The flag of GFP_ATOMIC is given to the call of kmalloc when building node
tree, but the call is not atomic context. The call of
fw_core_handle_bus_reset() and fw_core_remove_card() builds the tree,
while they are done in specific workqueue or pci remove callback.

This commit obsolete the usage of GFP_ATOMIC.

Link: https://lore.kernel.org/r/20230604070255.172700-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto