On some i.MX SoCs' low power mode, such as i.MX7D's LPSR(low power
state retention), UART iomux settings will be lost, need to add
pinctrl sleep/default mode switch during suspend/resume to make
sure UART iomux settings are correct after resume.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In noirq suspend/resume stage with no_console_suspend enabled,
imx_uart_console_write() may be called to print out log_buf
message by printk(), so there will be race condition between
imx_uart_console_write() and imx_uart_save/restore_context(),
need to add lock to protect the registers save/restore operations.
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Before the program enters the uart ISR, the local interrupt has been
disabled by the system, so it's not appropriate to use spin_lock_irqsave
interface in the ISR.
Signed-off-by: jun qian <hangdianqj@163.com>
Reviewed-by: Barry Song <21cnbao@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Driver console functions are using pointer to static array with fixed
size. There can be only one serial console at the time which is found
by register_console(). register_console() is filling cons->index to
port->line value.
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

register_console is called twice once from

uart_add_one_port -> uart_configure_port
remove the double call
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Move uart register to probe.
This is in preparation of removing the hardcoding of number of uarts.
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

At probe the uartlite is getting configured.
Enable the clocks before assiging uart and
disable after probe is done.
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The printk() in serial8250_interrupt() was once hidden behind a debug
macro in commit f4f653e9 ("serial: 8250, disable "too much work"
messages") and reverted back in commit 12de375e ("Revert "serial:
8250, disable "too much work" messages"").

This was introduced first in 0.99.13k with the "serial" driver itself
(and called pass_number with a limit of 64 and no print). In 1.1.13 it
was renamed to pass_counter and the printk was behind #if 0. In 1.1.94
the limit of 64 was increased to 256 and hidden behind
RS_ISR_PASS_LIMIT. With this change the #if 0 turned into #if 1. It
slowly become what we have today with a loop limit of 512.

Usually, that printk isn't hit. However on KVM with a busy UART and
overloaded host it might happen. It is also likely with threaded
interrupts and a task which preempts the interrupt handler.

If the UART has (legitimate) work to do and we break out of the loop,
nothing changes: the interrupt is most likely already pending in the
interrupt controller and we end up in the handler anyway. This printk is
hardly helping.

Older kernels also had a comment saying that a bad configuration might
lead to this but I don't see how that should happen because a wrongly
configured interrupt number would let the handler leave "early" with
IRQ_NONE and the spurious detected will handle that (weill since 2.6.11,
before that we had no spurious detector). In that case, we would never
loop that often here.

This loop looks like an optimisation in order to pull the bytes from the
FIFO which were received while we were already here instead of waiting
for the interrupt. This might have been a good idea while the CPUs were
slow and FIFOs small.
There are other serial driver in tree, like the amba-pl*, which also
have this kind of a loop but without the printk (and were based on this
driver).

Remove the printk which might trigger in otherwise valid situtations.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

There's an error when compiled with restrict:

drivers/tty/serial/kgdboc.c: In function ‘configure_kgdboc’:
drivers/tty/serial/kgdboc.c:137:2: error: ‘strcpy’ source argument is the same
as destination [-Werror=restrict]
  strcpy(config, opt);
  ^~~~~~~~~~~~~~~~~~~

As the error implies, this is from trying to use config as both source and
destination. Drop the call to the function where config is the argument
since nothing else happens in the function.
Signed-off-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pr_* is preferred according to scripts/checkpatch.pl.

Cc: jason.wessel@windriver.com
Cc: gregkh@linuxfoundation.org
Cc: jslaby@suse.com
Signed-off-by: He Zhe <zhe.he@windriver.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kgdboc_option_setup does not check input argument before passing it
to strlen. The argument would be a NULL pointer if "ekgdboc", without
its value, is set in command line and thus cause the following panic.

PANIC: early exception 0xe3 IP 10:ffffffff8fbbb620 error 0 cr2 0x0
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 4.18-rc8+ #1
[    0.000000] RIP: 0010:strlen+0x0/0x20
...
[    0.000000] Call Trace
[    0.000000]  ? kgdboc_option_setup+0x9/0xa0
[    0.000000]  ? kgdboc_early_init+0x6/0x1b
[    0.000000]  ? do_early_param+0x4d/0x82
[    0.000000]  ? parse_args+0x212/0x330
[    0.000000]  ? rdinit_setup+0x26/0x26
[    0.000000]  ? parse_early_options+0x20/0x23
[    0.000000]  ? rdinit_setup+0x26/0x26
[    0.000000]  ? parse_early_param+0x2d/0x39
[    0.000000]  ? setup_arch+0x2f7/0xbf4
[    0.000000]  ? start_kernel+0x5e/0x4c2
[    0.000000]  ? load_ucode_bsp+0x113/0x12f
[    0.000000]  ? secondary_startup_64+0xa5/0xb0

This patch adds a check to prevent the panic.

Cc: stable@vger.kernel.org
Cc: jason.wessel@windriver.com
Cc: gregkh@linuxfoundation.org
Cc: jslaby@suse.com
Signed-off-by: He Zhe <zhe.he@windriver.com>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Enable automatic flow control which should ensure that there is no
mainteinance in connection for zcu100 BT case.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Acked-by: Nava kishore Manne <navam@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Record port ID in device data structure to be have it connected to
certain instance.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Every instance is registering own struct console and struct uart_driver
with minor number which corresponds to alias ID (or 0 now) and with 1 uart
port. The same alias ID is saved to tty_driver->name_base which is key
field for creating ttyPSX name.

Because name_base and minor number are setup already there is no need to
setup any port->line number because 0 is the right value.

Unfortunately this driver is setting up major number to 0 for using
dynamic assignment and kernel is allocating different major numbers for
every instance instead of using the same major and different minor
number.

~# ls -la /dev/ttyPS*
crw-------    1 root     root      252,   0 Jan  1 03:36 /dev/ttyPS0
crw--w----    1 root     root      253,   1 Jan  1 00:00 /dev/ttyPS1

When major number is not 0. For example 252 then major/minor
combinations are in expected form

~# ls -la /dev/ttyPS*
crw-------    1 root     root      252,   0 Jan  1 04:04 /dev/ttyPS0
crw--w----    1 root     root      252,   1 Jan  1 00:00 /dev/ttyPS1

Driver is not freeing struct cdns_uart_console in case that instance is
not used as console. The reason is that console is incorrectly unregistred
and "console [0] disabled" message will be shown.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Change logic how console_port is setup by using CON_ENABLED flag
instead of index. There will be unique cdns_uart_console() structures
that's why code can't use id for console_port assignment.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This is preparation step for dynamic port allocation without
CDNS_UART_NR_PORTS macro. Fill the structure only once at probe.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Register uart driver in probe to be able to register one device with
unique major/minor separately. Also calculate number of instances of
this driver to be able to call uart_unregister_driver() when there is no
instance.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

This cosmetic change is done only for having next patch much easier to
read. Moving id setup higher in probe is not affecting any usage of this
driver and it also simplify error path.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

cdns_uart_suspend()/resume() and remove() are using static reference
to struct uart_driver. Assign this reference to private data structure
as preparation step for dynamic struct uart_driver allocation.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The driver's suspend/resume functions were buggy.
If UART node contains any child node in the DT and
the child is established a communication path with
the parent UART. The relevant /dev/ttyPS* node will
be not available for other operations.
If the driver is trying to do any operations like
suspend/resume without checking the tty->dev status
it leads to the kernel crash/hang.

This patch fix this issue by call the device_may_wake()
with the generic parameter of type struct device.
in the uart suspend and resume paths.

It also fixes a race condition in the uart suspend
path(i.e uart_suspend_port() should be called at the
end of cdns_uart_suspend API this path updates the same)
Signed-off-by: Nava kishore Manne <navam@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Writing zero and NULLs to already initialized fields is not needed.
Remove this additional writes.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

When console device is rebinded, console_setup() is called again.
But marking it as __init means that function will be clear after boot is
complete. If console device is binded again console_setup() is not found
and error "Unable to handle kernel paging request at virtual address"
is reported.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

We want the tty fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

The Code of Conflict is not achieving its implicit goal of fostering
civility and the spirit of 'be excellent to each other'.  Explicit
guidelines have demonstrated success in other projects and other areas
of the kernel.

Here is a Code of Conduct statement for the wider kernel.  It is based
on the Contributor Covenant as described at www.contributor-covenant.org

From this point forward, we should abide by these rules in order to help
make the kernel community a welcoming environment to participate in.
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Olof Johansson <olof@lxom.net>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull x86 fixes from Ingol Molnar:
 "Misc fixes:

   - EFI crash fix

   - Xen PV fixes

   - do not allow PTI on 2-level 32-bit kernels for now

   - documentation fix"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/APM: Fix build warning when PROC_FS is not enabled
  Revert "x86/mm/legacy: Populate the user page-table with user pgd's"
  x86/efi: Load fixmap GDT in efi_call_phys_epilog() before setting %cr3
  x86/xen: Disable CPU0 hotplug for Xen PV
  x86/EISA: Don't probe EISA bus for Xen PV guests
  x86/doc: Fix Documentation/x86/earlyprintk.txt

Pull scheduler fixes from Ingo Molnar:
 "Misc fixes: various scheduler metrics corner case fixes, a
  sched_features deadlock fix, and a topology fix for certain NUMA
  systems"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix kernel-doc notation warning
  sched/fair: Fix load_balance redo for !imbalance
  sched/fair: Fix scale_rt_capacity() for SMT
  sched/fair: Fix vruntime_normalized() for remote non-migration wakeup
  sched/pelt: Fix update_blocked_averages() for RT and DL classes
  sched/topology: Set correct NUMA topology type
  sched/debug: Fix potential deadlock when writing to sched_features

Pull perf fixes from Ingo Molnar:
 "Mostly tooling fixes, but also breakpoint and x86 PMU driver fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  perf tools: Fix maps__find_symbol_by_name()
  tools headers uapi: Update tools's copy of linux/if_link.h
  tools headers uapi: Update tools's copy of linux/vhost.h
  tools headers uapi: Update tools's copies of kvm headers
  tools headers uapi: Update tools's copy of drm/drm.h
  tools headers uapi: Update tools's copy of asm-generic/unistd.h
  tools headers uapi: Update tools's copy of linux/perf_event.h
  perf/core: Force USER_DS when recording user stack data
  perf/UAPI: Clearly mark __PERF_SAMPLE_CALLCHAIN_EARLY as internal use
  perf/x86/intel: Add support/quirk for the MISPREDICT bit on Knights Landing CPUs
  perf annotate: Fix parsing aarch64 branch instructions after objdump update
  perf probe powerpc: Ignore SyS symbols irrespective of endianness
  perf event-parse: Use fixed size string for comms
  perf util: Fix bad memory access in trace info.
  perf tools: Streamline bpf examples and headers installation
  perf evsel: Fix potential null pointer dereference in perf_evsel__new_idx()
  perf arm64: Fix include path for asm-generic/unistd.h
  perf/hw_breakpoint: Simplify breakpoint enable in perf_event_modify_breakpoint
  perf/hw_breakpoint: Enable breakpoint in modify_user_hw_breakpoint
  perf/hw_breakpoint: Remove superfluous bp->attr.disabled = 0
  ...

Pull locking fixes from Ingo Molnar:
 "Misc fixes: liblockdep fixes and ww_mutex fixes"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/ww_mutex: Fix spelling mistake "cylic" -> "cyclic"
  locking/lockdep: Delete unnecessary #include
  tools/lib/lockdep: Add dummy task_struct state member
  tools/lib/lockdep: Add empty nmi.h
  tools/lib/lockdep: Update Sasha Levin email to MSFT
  jump_label: Fix typo in warning message
  locking/mutex: Fix mutex debug call and ww_mutex documentation

Fix build warning in apm_32.c when CONFIG_PROC_FS is not enabled:

../arch/x86/kernel/apm_32.c:1643:12: warning: 'proc_apm_show' defined but not used [-Wunused-function]
 static int proc_apm_show(struct seq_file *m, void *v)

Fixes: 3f3942ac ("proc: introduce proc_create_single{,_data}")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Jiri Kosina <jikos@kernel.org>
Link: https://lkml.kernel.org/r/be39ac12-44c2-4715-247f-4dcc3c525b8b@infradead.org

Pull cifs fixes from Steve French:
 "Fixes for four CIFS/SMB3 potential pointer overflow issues, one minor
  build fix, and a build warning cleanup"

* tag '4.19-rc3-smb3-cifs' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: read overflow in is_valid_oplock_break()
  cifs: integer overflow in in SMB2_ioctl()
  CIFS: fix wrapping bugs in num_entries()
  cifs: prevent integer overflow in nxt_dir_entry()
  fs/cifs: require sha512
  fs/cifs: suppress a string overflow warning

Pull NFS client bugfixes from Anna Schumaker:
 "These are a handful of fixes for problems that Trond found. Patch #1
  and #3 have the same name, a second issue was found after applying the
  first patch.

  Stable bugfixes:
   - v4.17+: Fix tracepoint Oops in initiate_file_draining()
   - v4.11+: Fix an infinite loop on I/O

  Other fixes:
   - Return errors if a waiting layoutget is killed
   - Don't open code clearing of delegation state"

* tag 'nfs-for-4.19-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  NFS: Don't open code clearing of delegation state
  NFSv4.1 fix infinite loop on I/O.
  NFSv4: Fix a tracepoint Oops in initiate_file_draining()
  pNFS: Ensure we return the error if someone kills a waiting layoutget
  NFSv4: Fix a tracepoint Oops in initiate_file_draining()

Pull tracing fix from Steven Rostedt:
 "This fixes an issue with the build system caused by a change that
  modifies CC_FLAGS_FTRACE. The issue is that it breaks the dependencies
  and causes "make targz-pkg" to rebuild the entire world"

* tag 'trace-v4.19-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing/Makefile: Fix handling redefinition of CC_FLAGS_FTRACE

Pull DeviceTree fix from Rob Herring:
 "One regression for a 20 year old PowerMac:

   - Fix a regression on systems having a DT without any phandles which
     happens on a PowerMac G3"

* tag 'devicetree-fixes-for-4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  of: fix phandle cache creation for DTs with no phandles

Pull xen fixes from Juergen Gross:
 "This contains some minor cleanups and fixes:

   - a new knob for controlling scrubbing of pages returned by the Xen
     balloon driver to the Xen hypervisor to address a boot performance
     issue seen in large guests booted pre-ballooned

   - a fix of a regression in the gntdev driver which made it impossible
     to use fully virtualized guests (HVM guests) with a 4.19 based dom0

   - a fix in Xen cpu hotplug functionality which could be triggered by
     wrong admin commands (setting number of active vcpus to 0)

  One further note: the patches have all been under test for several
  days in another branch. This branch has been rebased in order to avoid
  merge conflicts"

* tag 'for-linus-4.19c-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/gntdev: fix up blockable calls to mn_invl_range_start
  xen: fix GCC warning and remove duplicate EVTCHN_ROW/EVTCHN_COL usage
  xen: avoid crash in disable_hotplug_cpu
  xen/balloon: add runtime control for scrubbing ballooned out pages
  xen/manage: don't complain about an empty value in control/sysrq node

Pull Xtensa fixes and cleanups from Max Filippov:

 - don't allocate memory in platform_setup as the memory allocator is
   not initialized at that point yet;

 - remove unnecessary ifeq KBUILD_SRC from arch/xtensa/Makefile;

 - enable SG chaining in arch/xtensa/Kconfig.

* tag 'xtensa-20180914' of git://github.com/jcmvbkbc/linux-xtensa:
  xtensa: enable SG chaining in Kconfig
  xtensa: remove unnecessary KBUILD_SRC ifeq conditional
  xtensa: ISS: don't allocate memory in platform_setup

Pull arm64 fixes from Will Deacon:
 "The trickle of arm64 fixes continues to come in.

  Nothing that's the end of the world, but we've got a fix for PCI IO
  port accesses, an accidental naked "asm goto" and a fix to the
  vmcoreinfo PT_NOTE merged this time around which we'd like to get
  sorted before it becomes ABI.

   - Fix ioport_map() mapping the wrong physical address for some I/O
     BARs

   - Remove direct use of "asm goto", since some compilers don't like
     that

   - Ensure kimage_voffset is always present in vmcoreinfo PT_NOTE"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  asm-generic: io: Fix ioport_map() for !CONFIG_GENERIC_IOMAP && CONFIG_INDIRECT_PIO
  arm64: kernel: arch_crash_save_vmcoreinfo() should depend on CONFIG_CRASH_CORE
  arm64: jump_label.h: use asm_volatile_goto macro instead of "asm goto"

Add a helper for the case when the nfs4 open state has been set to use
a delegation stateid, and we want to revert to using the open stateid.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

The previous fix broke recovery of delegated stateids because it assumes
that if we did not mark the delegation as suspect, then the delegation has
effectively been revoked, and so it removes that delegation irrespectively
of whether or not it is valid and still in use. While this is "mostly
harmless" for ordinary I/O, we've seen pNFS fail with LAYOUTGET spinning
in an infinite loop while complaining that we're using an invalid stateid
(in this case the all-zero stateid).

What we rather want to do here is ensure that the delegation is always
correctly marked as needing testing when that is the case. So we want
to close the loophole offered by nfs4_schedule_stateid_recovery(),
which marks the state as needing to be reclaimed, but not the
delegation that may be backing it.

Fixes: 0e3d3e5d ("NFSv4.1 fix infinite loop on IO BAD_STATEID error")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.11+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Now that the value of 'ino' can be NULL or an ERR_PTR(), we need to
change the test in the tracepoint.

Fixes: ce5624f7 ("NFSv4: Return NFS4ERR_DELAY when a layout fails...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.17+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>