android_kernel_motorola_sm6375/include
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Logan Gunthorpe f99958a96c dmaengine: Store module owner in dma_device struct
[ Upstream commit dae7a589c18a4d979d5f14b09374e871b995ceb1 ]

dma_chan_to_owner() dereferences the driver from the struct device to
obtain the owner and call module_[get|put](). However, if the backing
device is unbound before the dma_device is unregistered, the driver
will be cleared and this will cause a NULL pointer dereference.

Instead, store a pointer to the owner module in the dma_device struct
so the module reference can be properly put when the channel is put, even
if the backing device was destroyed first.

This change helps to support a safer unbind of DMA engines.
If the dma_device is unregistered in the driver's remove function,
there's no guarantee that there are no existing clients and a users
action may trigger the WARN_ONCE in dma_async_device_unregister()
which is unlikely to leave the system in a consistent state.
Instead, a better approach is to allow the backing driver to go away
and fail any subsequent requests to it.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Link: https://lore.kernel.org/r/20191216190120.21374-2-logang@deltatee.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-24 08:36:40 +01:00
..
acpi ACPICA: Introduce acpi_any_gpe_status_set() 2020-02-19 19:52:57 +01:00
asm-generic mm/mmu_gather: invalidate TLB correctly on batch allocation failure and flush 2020-02-11 04:35:42 -08:00
clocksource
crypto crypto: algif_skcipher - Use chunksize instead of blocksize 2020-01-17 19:48:46 +01:00
drm
dt-bindings dt-bindings: reset: meson8b: fix duplicate reset IDs 2020-01-23 08:22:28 +01:00
keys
kvm
linux dmaengine: Store module owner in dma_device struct 2020-02-24 08:36:40 +01:00
math-emu
media media: v4l2-device.h: Explicitly compare grp{id,mask} to zero in v4l2_device macros 2020-02-24 08:36:36 +01:00
misc
net bonding/alb: properly access headers in bond_alb_xmit() 2020-02-11 04:35:48 -08:00
pcmcia
ras
rdma IB/core: Let IB core distribute cache update events 2020-02-24 08:36:26 +01:00
scsi
soc
sound ALSA: hda: Apply aligned MMIO access only conditionally 2020-02-11 04:35:15 -08:00
target
trace rcu: Fix data-race due to atomic_t copy-by-value 2020-02-24 08:36:23 +01:00
uapi rdma: Remove nes ABI header 2020-01-17 19:48:39 +01:00
vdso
video
xen
Kbuild