linux-stable.git/drivers/tty/hvc, branch linux-6.3.y

Merge tag 'for-linus-6.3-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2023-03-24T16:44:43+00:00

Pull xen fixes from Juergen Gross:

 - fix build warning

 - avoid concurrent accesses to the Xen PV console ring page

* tag 'for-linus-6.3-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/PVH: avoid 32-bit build warning when obtaining VGA console info
  hvc/xen: prevent concurrent accesses to the shared ring

hvc/xen: prevent concurrent accesses to the shared ring

2023-03-22T15:59:39+00:00

The hvc machinery registers both a console and a tty device based on
the hv ops provided by the specific implementation.  Those two
interfaces however have different locks, and there's no single locks
that's shared between the tty and the console implementations, hence
the driver needs to protect itself against concurrent accesses.
Otherwise concurrent calls using the split interfaces are likely to
corrupt the ring indexes, leaving the console unusable.

Introduce a lock to xencons_info to serialize accesses to the shared
ring.  This is only required when using the shared memory console,
concurrent accesses to the hypercall based console implementation are
not an issue.

Note the conditional logic in domU_read_console() is slightly modified
so the notify_daemon() call can be done outside of the locked region:
it's an hypercall and there's no need for it to be done with the lock
held.

Fixes: b536b4b96230 ('xen: use the hvc console infrastructure for Xen console')
Signed-off-by: Roger Pau Monné 
Reviewed-by: Juergen Gross 
Link: https://lore.kernel.org/r/20221130150919.13935-1-roger.pau@citrix.com
Signed-off-by: Juergen Gross

hvcs: Synchronize hotplug remove with port free

2023-02-08T12:09:15+00:00

Synchronizes hotplug remove with the freeing of the port.
This ensures we have freed all the memory associated with
this port and are not leaking memory.

Signed-off-by: Brian King 
Link: https://lore.kernel.org/r/20230203155802.404324-6-brking@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman

hvcs: Use vhangup in hotplug remove

2023-02-08T12:09:15+00:00

When hotplug removing an hvcs device, we need to ensure the
hangup processing is done prior to exiting the remove function,
so use tty_vhangup to do the hangup processing directly
rather than using tty_hangup which simply schedules the hangup
work for later execution.

Signed-off-by: Brian King 
Link: https://lore.kernel.org/r/20230203155802.404324-5-brking@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman

hvcs: Get reference to tty in remove

2023-02-08T12:09:15+00:00

Grab a reference to the tty when removing the hvcs to ensure
it does not get freed unexpectedly.

Signed-off-by: Brian King 
Link: https://lore.kernel.org/r/20230203155802.404324-4-brking@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman

hvcs: Use driver groups to manage driver attributes

2023-02-08T12:09:14+00:00

Rather than manually creating attributes for the hvcs driver,
let the driver core do this for us. This also fixes some hotplug
remove issues and ensures that cleanup of these attributes
is done in the right order.

Signed-off-by: Brian King 
Link: https://lore.kernel.org/r/20230203155802.404324-3-brking@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman

hvcs: Use dev_groups to manage hvcs device attributes

2023-02-08T12:09:14+00:00

Use the dev_groups functionality to manage the attribute groups
for hvcs devices. This simplifies the code and also eliminates
errors coming from kernfs when attempting to remove a console
device that is in use.

Signed-off-by: Brian King 
Link: https://lore.kernel.org/r/20230203155802.404324-2-brking@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman

hvcs: Fix hvcs port reference counting

2023-02-02T10:51:03+00:00

The hvcs driver only ever gets two references to the port. One
at initialization time, and one at install time. Remove the code
that was trying to do multiple port puts for each open, which
would result in more puts than gets.

Signed-off-by: Brian King 
Link: https://lore.kernel.org/r/20230201195743.303163-2-brking@linux.vnet.ibm.com
Signed-off-by: Greg Kroah-Hartman

tty: Call ->dtr_rts() parameter active consistently

2023-01-19T15:04:35+00:00

Convert various parameter names for ->dtr_rts() and related functions
from onoff, on, and raise to active.

Reviewed-by: Jiri Slaby 
Acked-by: Ulf Hansson  # For MMC
Signed-off-by: Ilpo Järvinen 
Link: https://lore.kernel.org/r/20230117090358.4796-12-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman

tty: Convert ->dtr_rts() to take bool argument

2023-01-19T15:04:35+00:00

Convert the raise/on parameter in ->dtr_rts() to bool through the
callchain. The parameter is used like bool. In USB serial, there
remains a few implicit bool -> larger type conversions because some
devices use u8 in their control messages.

In moxa_tiocmget(), dtr variable was reused for line status which
requires int so use a separate variable for status.

Reviewed-by: Jiri Slaby 
Acked-by: Ulf Hansson  # For MMC
Signed-off-by: Ilpo Järvinen 
Link: https://lore.kernel.org/r/20230117090358.4796-8-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman