linux/include
Benjamin Herrenschmidt 726e410979 drivers: core: Remove glue dirs from sysfs earlier
For devices with a class, we create a "glue" directory between
the parent device and the new device with the class name.

This directory is never "explicitely" removed when empty however,
this is left to the implicit sysfs removal done by kobject_release()
when the object loses its last reference via kobject_put().

This is problematic because as long as it's not been removed from
sysfs, it is still present in the class kset and in sysfs directory
structure.

The presence in the class kset exposes a use after free bug fixed
by the previous patch, but the presence in sysfs means that until
the kobject is released, which can take a while (especially with
kobject debugging), any attempt at re-creating such as binding a
new device for that class/parent pair, will result in a sysfs
duplicate file name error.

This fixes it by instead doing an explicit kobject_del() when
the glue dir is empty, by keeping track of the number of
child devices of the gluedir.

This is made easy by the fact that all glue dir operations are
done with a global mutex, and there's already a function
(cleanup_glue_dir) called in all the right places taking that
mutex that can be enhanced for this. It appears that this was
in fact the intent of the function, but the implementation was
wrong.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-16 13:42:02 +02:00
..
acpi ACPI / processor: Finish making acpi_processor_ppc_has_changed() void 2018-06-20 10:50:40 +02:00
asm-generic iommu: Remove IOMMU_OF_DECLARE 2018-07-10 17:22:35 +02:00
clocksource
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2018-06-05 15:51:21 -07:00
drm drm for v4.18-rc1 2018-06-06 08:16:33 -07:00
dt-bindings ARM: SoC driver updates 2018-06-11 18:15:22 -07:00
keys docs: Fix some broken references 2018-06-15 18:10:01 -03:00
kvm
linux drivers: core: Remove glue dirs from sysfs earlier 2018-07-16 13:42:02 +02:00
math-emu
media media: v4l2-core: push taking ioctl mutex down to ioctl handler 2018-05-28 16:31:44 -04:00
memory
misc ocxl: Expose the thread_id needed for wait on POWER9 2018-06-03 20:40:32 +10:00
net net/ipv6: respect rcu grace period before freeing fib6_info 2018-06-20 07:57:23 +09:00
pcmcia
ras
rdma 4.18-rc 2018-06-21 07:22:30 +09:00
scsi SCSI misc on 20180610 2018-06-10 13:01:12 -07:00
soc ARM: SoC: late updates 2018-06-11 18:19:45 -07:00
sound sound updates for 4.18 2018-06-06 09:08:38 -07:00
target
trace NFS client updates for Linux 4.18 2018-06-12 10:09:03 -07:00
uapi for-linus-20180623 2018-06-24 06:33:54 +08:00
video fbdev changes for v4.18: 2018-06-17 05:00:24 +09:00
xen xen: fixes for 4.18-rc2 2018-06-23 20:44:11 +08:00