linux.git/drivers/rpmsg/rpmsg_char.c, branch v5.17

rpmsg: char: Fix race between the release of rpmsg_eptdev and cdev

2022-01-17T22:39:58+00:00

struct rpmsg_eptdev contains a struct cdev. The current code frees
the rpmsg_eptdev struct in rpmsg_eptdev_destroy(), but the cdev is
a managed object, therefore its release is not predictable and the
rpmsg_eptdev could be freed before the cdev is entirely released.

The cdev_device_add/del() API was created to address this issue
(see commit '233ed09d7fda ("chardev: add helper function to register
char devs with a struct device")'), use it instead of cdev add/del().

Fixes: c0cdc19f84a4 ("rpmsg: Driver for user space endpoint interface")
Suggested-by: Bjorn Andersson 
Signed-off-by: Matthias Kaehlcke 
Reviewed-by: Mathieu Poirier 
Reviewed-by: Stephen Boyd 
Reviewed-by: Bjorn Andersson 
Signed-off-by: Bjorn Andersson 
Link: https://lore.kernel.org/r/20220110104706.v6.2.Idde68b05b88d4a2e6e54766c653f3a6d9e419ce6@changeid

rpmsg: char: Fix race between the release of rpmsg_ctrldev and cdev

2022-01-17T22:38:48+00:00

struct rpmsg_ctrldev contains a struct cdev. The current code frees
the rpmsg_ctrldev struct in rpmsg_ctrldev_release_device(), but the
cdev is a managed object, therefore its release is not predictable
and the rpmsg_ctrldev could be freed before the cdev is entirely
released, as in the backtrace below.

[   93.625603] ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x7c
[   93.636115] WARNING: CPU: 0 PID: 12 at lib/debugobjects.c:488 debug_print_object+0x13c/0x1b0
[   93.644799] Modules linked in: veth xt_cgroup xt_MASQUERADE rfcomm algif_hash algif_skcipher af_alg uinput ip6table_nat fuse uvcvideo videobuf2_vmalloc venus_enc venus_dec videobuf2_dma_contig hci_uart btandroid btqca snd_soc_rt5682_i2c bluetooth qcom_spmi_temp_alarm snd_soc_rt5682v
[   93.715175] CPU: 0 PID: 12 Comm: kworker/0:1 Tainted: G    B             5.4.163-lockdep #26
[   93.723855] Hardware name: Google Lazor (rev3 - 8) with LTE (DT)
[   93.730055] Workqueue: events kobject_delayed_cleanup
[   93.735271] pstate: 60c00009 (nZCv daif +PAN +UAO)
[   93.740216] pc : debug_print_object+0x13c/0x1b0
[   93.744890] lr : debug_print_object+0x13c/0x1b0
[   93.749555] sp : ffffffacf5bc7940
[   93.752978] x29: ffffffacf5bc7940 x28: dfffffd000000000
[   93.758448] x27: ffffffacdb11a800 x26: dfffffd000000000
[   93.763916] x25: ffffffd0734f856c x24: dfffffd000000000
[   93.769389] x23: 0000000000000000 x22: ffffffd0733c35b0
[   93.774860] x21: ffffffd0751994a0 x20: ffffffd075ec27c0
[   93.780338] x19: ffffffd075199100 x18: 00000000000276e0
[   93.785814] x17: 0000000000000000 x16: dfffffd000000000
[   93.791291] x15: ffffffffffffffff x14: 6e6968207473696c
[   93.796768] x13: 0000000000000000 x12: ffffffd075e2b000
[   93.802244] x11: 0000000000000001 x10: 0000000000000000
[   93.807723] x9 : d13400dff1921900 x8 : d13400dff1921900
[   93.813200] x7 : 0000000000000000 x6 : 0000000000000000
[   93.818676] x5 : 0000000000000080 x4 : 0000000000000000
[   93.824152] x3 : ffffffd0732a0fa4 x2 : 0000000000000001
[   93.829628] x1 : ffffffacf5bc7580 x0 : 0000000000000061
[   93.835104] Call trace:
[   93.837644]  debug_print_object+0x13c/0x1b0
[   93.841963]  __debug_check_no_obj_freed+0x25c/0x3c0
[   93.846987]  debug_check_no_obj_freed+0x18/0x20
[   93.851669]  slab_free_freelist_hook+0xbc/0x1e4
[   93.856346]  kfree+0xfc/0x2f4
[   93.859416]  rpmsg_ctrldev_release_device+0x78/0xb8
[   93.864445]  device_release+0x84/0x168
[   93.868310]  kobject_cleanup+0x12c/0x298
[   93.872356]  kobject_delayed_cleanup+0x10/0x18
[   93.876948]  process_one_work+0x578/0x92c
[   93.881086]  worker_thread+0x804/0xcf8
[   93.884963]  kthread+0x2a8/0x314
[   93.888303]  ret_from_fork+0x10/0x18

The cdev_device_add/del() API was created to address this issue (see
commit '233ed09d7fda ("chardev: add helper function to register char
devs with a struct device")'), use it instead of cdev add/del().

Fixes: c0cdc19f84a4 ("rpmsg: Driver for user space endpoint interface")
Signed-off-by: Sujit Kautkar 
Signed-off-by: Matthias Kaehlcke 
Reviewed-by: Mathieu Poirier 
Reviewed-by: Bjorn Andersson 
Reviewed-by: Stephen Boyd 
Signed-off-by: Bjorn Andersson 
Link: https://lore.kernel.org/r/20220110104706.v6.1.Iaac908f3e3149a89190ce006ba166e2d3fd247a3@changeid

rpmsg: char: Add pr_fmt() to prefix messages

2021-11-18T17:27:15+00:00

Make all messages to be prefixed in a unified way.
Add pr_fmt() to achieve this.

Signed-off-by: Arnaud Pouliquen 
Link: https://lore.kernel.org/r/20211108135945.3364-1-arnaud.pouliquen@foss.st.com
Signed-off-by: Mathieu Poirier

rpmsg: char: Remove useless include

2021-10-08T22:21:20+00:00

No facility requests the include of rpmsg_internal.h header file.

Signed-off-by: Arnaud Pouliquen 
Reviewed-by: Mathieu Poirier 
Signed-off-by: Bjorn Andersson 
Link: https://lore.kernel.org/r/20210712123752.10449-2-arnaud.pouliquen@foss.st.com

rpmsg: char: Return an error if device already open

2021-03-17T19:16:58+00:00

The rpmsg_create_ept function is invoked when the device is opened.
As only one endpoint must be created per device. It is not possible to
open the same device twice. But there is nothing to prevent multi open.
Return -EBUSY when device is already opened to have a generic error
instead of relying on the back-end to potentially detect the error.

Without this patch for instance the GLINK driver return -EBUSY while
the virtio bus return -ENOSPC.

Reviewed-by: Bjorn Andersson 
Reviewed-by: Mathieu Poirier 
Signed-off-by: Arnaud Pouliquen 
Link: https://lore.kernel.org/r/20210311140413.31725-7-arnaud.pouliquen@foss.st.com
Signed-off-by: Bjorn Andersson

rpmsg: char: Use rpmsg_sendto to specify the message destination address

2021-03-17T19:16:36+00:00

When the endpoint device is created by the application, a destination
address is specified in the rpmsg_channel_info structure. Since the
rpmsg_endpoint structure does not store the destination address,
this destination address must be specified when sending a message.

Replaces rpmsg_send with rpmsg_sendto to allow to specify the
destination address. This implementation is requested for compatibly with
some rpmsg backends like the virtio backend.

For this, the GLINK an SMD drivers have been updated to support the
rpmsg_sendto, even if the destination address is ignored for these
backends. For these drivers, the rpmsg_send and rpmsg_trysend ops are
preserved to avoid breaking the legacy.

Signed-off-by: Arnaud Pouliquen 

Reviewed-by: Bjorn Andersson 
Reviewed-by: Mathieu Poirier 
Link: https://lore.kernel.org/r/20210311140413.31725-5-arnaud.pouliquen@foss.st.com
Signed-off-by: Bjorn Andersson

rpmsg: char: Rename rpmsg_char_init to rpmsg_chrdev_init

2021-03-17T19:16:04+00:00

To be coherent with the other functions which are prefixed by
rpmsg_chrdev, rename the rpmsg_char_init function.

Reviewed-by: Bjorn Andersson 
Reviewed-by: Mathieu Poirier 
Signed-off-by: Arnaud Pouliquen 
Link: https://lore.kernel.org/r/20210311140413.31725-2-arnaud.pouliquen@foss.st.com
Signed-off-by: Bjorn Andersson

Merge tag 'rpmsg-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/andersson/remoteproc

2019-12-02T02:39:24+00:00

Pull rpmsg updates from Bjorn Andersson:
 "This contains a number of bug fixes to the GLINK transport driver, an
  off-by-one in the GLINK smem driver and a memory leak fix in the rpmsg
  char driver"

* tag 'rpmsg-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/andersson/remoteproc:
  rpmsg: Fix Kconfig indentation
  rpmsg: char: Simplify 'rpmsg_eptdev_release()'
  rpmsg: glink: Free pending deferred work on remove
  rpmsg: glink: Don't send pending rx_done during remove
  rpmsg: glink: Fix rpmsg_register_device err handling
  rpmsg: glink: Put an extra reference during cleanup
  rpmsg: glink: Fix use after free in open_ack TIMEOUT case
  rpmsg: glink: Fix reuse intents memory leak issue
  rpmsg: glink: Set tail pointer to 0 at end of FIFO
  rpmsg: char: release allocated memory

rpmsg: char: Simplify 'rpmsg_eptdev_release()'

2019-11-09T00:49:37+00:00

Use 'skb_queue_purge()' instead of re-implementing it.

Signed-off-by: Christophe JAILLET 
Signed-off-by: Bjorn Andersson

compat_ioctl: move more drivers to compat_ptr_ioctl

2019-10-23T15:23:44+00:00

The .ioctl and .compat_ioctl file operations have the same prototype so
they can both point to the same function, which works great almost all
the time when all the commands are compatible.

One exception is the s390 architecture, where a compat pointer is only
31 bit wide, and converting it into a 64-bit pointer requires calling
compat_ptr(). Most drivers here will never run in s390, but since we now
have a generic helper for it, it's easy enough to use it consistently.

I double-checked all these drivers to ensure that all ioctl arguments
are used as pointers or are ignored, but are not interpreted as integer
values.

Acked-by: Jason Gunthorpe 
Acked-by: Daniel Vetter 
Acked-by: Mauro Carvalho Chehab 
Acked-by: Greg Kroah-Hartman 
Acked-by: David Sterba 
Acked-by: Darren Hart (VMware) 
Acked-by: Jonathan Cameron 
Acked-by: Bjorn Andersson 
Acked-by: Dan Williams 
Signed-off-by: Arnd Bergmann