Commit Graph

6322 Commits

Author SHA1 Message Date
Linus Torvalds d38c07afc3 powerpc updates for 5.7
- A large series from Nick for 64-bit to further rework our exception vectors,
    and rewrite portions of the syscall entry/exit and interrupt return in C. The
    result is much easier to follow code that is also faster in general.
 
  - Cleanup of our ptrace code to split various parts out that had become badly
    intertwined with #ifdefs over the years.
 
  - Changes to our NUMA setup under the PowerVM hypervisor which should
    hopefully avoid non-sensical topologies which can lead to warnings from the
    workqueue code and other problems.
 
  - MAINTAINERS updates to remove some of our old orphan entries and update the
    status of others.
 
  - Quite a few other small changes and fixes all over the map.
 
 Thanks to:
   Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew Donnellan, Aneesh
   Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen Zhou, Christophe JAILLET,
   Christophe Leroy, Christoph Hellwig, Clement Courbet, Daniel Axtens, David
   Gibson, Douglas Miller, Fabiano Rosas, Fangrui Song, Ganesh Goudar, Gautham R.
   Shenoy, Greg Kroah-Hartman, Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie
   Halip, Jan Kara, Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger,
   Laurentiu Tudor, Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh
   Salgaonkar, Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira,
   Michael Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan
   Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers,
   Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat, Rasmus Villemoes, Ravi
   Bangoria, Roman Bolshakov, Sam Bobroff, Sandipan Das, Santosh S, Sedat Dilek,
   Segher Boessenkool, Shilpasri G Bhat, Sourabh Jain, Srikar Dronamraju, Stephen
   Rothwell, Tyrel Datwyler, Vaibhav Jain, YueHaibing.
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Merge tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Slightly late as I had to rebase mid-week to insert a bug fix:

   - A large series from Nick for 64-bit to further rework our exception
     vectors, and rewrite portions of the syscall entry/exit and
     interrupt return in C. The result is much easier to follow code
     that is also faster in general.

   - Cleanup of our ptrace code to split various parts out that had
     become badly intertwined with #ifdefs over the years.

   - Changes to our NUMA setup under the PowerVM hypervisor which should
     hopefully avoid non-sensical topologies which can lead to warnings
     from the workqueue code and other problems.

   - MAINTAINERS updates to remove some of our old orphan entries and
     update the status of others.

   - Quite a few other small changes and fixes all over the map.

  Thanks to: Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew
  Donnellan, Aneesh Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen
  Zhou, Christophe JAILLET, Christophe Leroy, Christoph Hellwig, Clement
  Courbet, Daniel Axtens, David Gibson, Douglas Miller, Fabiano Rosas,
  Fangrui Song, Ganesh Goudar, Gautham R. Shenoy, Greg Kroah-Hartman,
  Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie Halip, Jan Kara,
  Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger, Laurentiu Tudor,
  Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh Salgaonkar,
  Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira, Michael
  Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan
  Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick
  Desaulniers, Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat,
  Rasmus Villemoes, Ravi Bangoria, Roman Bolshakov, Sam Bobroff,
  Sandipan Das, Santosh S, Sedat Dilek, Segher Boessenkool, Shilpasri G
  Bhat, Sourabh Jain, Srikar Dronamraju, Stephen Rothwell, Tyrel
  Datwyler, Vaibhav Jain, YueHaibing"

* tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits)
  powerpc: Make setjmp/longjmp signature standard
  powerpc/cputable: Remove unnecessary copy of cpu_spec->oprofile_type
  powerpc: Suppress .eh_frame generation
  powerpc: Drop -fno-dwarf2-cfi-asm
  powerpc/32: drop unused ISA_DMA_THRESHOLD
  powerpc/powernv: Add documentation for the opal sensor_groups sysfs interfaces
  selftests/powerpc: Fix try-run when source tree is not writable
  powerpc/vmlinux.lds: Explicitly retain .gnu.hash
  powerpc/ptrace: move ptrace_triggered() into hw_breakpoint.c
  powerpc/ptrace: create ppc_gethwdinfo()
  powerpc/ptrace: create ptrace_get_debugreg()
  powerpc/ptrace: split out ADV_DEBUG_REGS related functions.
  powerpc/ptrace: move register viewing functions out of ptrace.c
  powerpc/ptrace: split out TRANSACTIONAL_MEM related functions.
  powerpc/ptrace: split out SPE related functions.
  powerpc/ptrace: split out ALTIVEC related functions.
  powerpc/ptrace: split out VSX related functions.
  powerpc/ptrace: drop PARAMETER_SAVE_AREA_OFFSET
  powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64
  powerpc/ptrace: remove unused header includes
  ...
2020-04-05 11:12:59 -07:00
Linus Torvalds 0ad5b053d4 Char/Misc driver patches for 5.7-rc1
Here is the big set of char/misc/other driver patches for 5.7-rc1.
 
 Lots of things in here, and it's later than expected due to some reverts
 to resolve some reported issues.  All is now clean with no reported
 problems in linux-next.
 
 Included in here is:
 	- interconnect updates
 	- mei driver updates
 	- uio updates
 	- nvmem driver updates
 	- soundwire updates
 	- binderfs updates
 	- coresight updates
 	- habanalabs updates
 	- mhi new bus type and core
 	- extcon driver updates
 	- some Kconfig cleanups
 	- other small misc driver cleanups and updates
 
 As mentioned, all have been in linux-next for a while, and with the last
 two reverts, all is calm and good.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big set of char/misc/other driver patches for 5.7-rc1.

  Lots of things in here, and it's later than expected due to some
  reverts to resolve some reported issues. All is now clean with no
  reported problems in linux-next.

  Included in here is:
   - interconnect updates
   - mei driver updates
   - uio updates
   - nvmem driver updates
   - soundwire updates
   - binderfs updates
   - coresight updates
   - habanalabs updates
   - mhi new bus type and core
   - extcon driver updates
   - some Kconfig cleanups
   - other small misc driver cleanups and updates

  As mentioned, all have been in linux-next for a while, and with the
  last two reverts, all is calm and good"

* tag 'char-misc-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (174 commits)
  Revert "driver core: platform: Initialize dma_parms for platform devices"
  Revert "amba: Initialize dma_parms for amba devices"
  amba: Initialize dma_parms for amba devices
  driver core: platform: Initialize dma_parms for platform devices
  bus: mhi: core: Drop the references to mhi_dev in mhi_destroy_device()
  bus: mhi: core: Initialize bhie field in mhi_cntrl for RDDM capture
  bus: mhi: core: Add support for reading MHI info from device
  misc: rtsx: set correct pcr_ops for rts522A
  speakup: misc: Use dynamic minor numbers for speakup devices
  mei: me: add cedar fork device ids
  coresight: do not use the BIT() macro in the UAPI header
  Documentation: provide IBM contacts for embargoed hardware
  nvmem: core: remove nvmem_sysfs_get_groups()
  nvmem: core: use is_bin_visible for permissions
  nvmem: core: use device_register and device_unregister
  nvmem: core: add root_only member to nvmem device struct
  extcon: axp288: Add wakeup support
  extcon: Mark extcon_get_edev_name() function as exported symbol
  extcon: palmas: Hide error messages if gpio returns -EPROBE_DEFER
  dt-bindings: extcon: usbc-cros-ec: convert extcon-usbc-cros-ec.txt to yaml format
  ...
2020-04-03 13:22:40 -07:00
Linus Torvalds 1f944f976d TTY/Serial patches for 5.7-rc1
Here is the big set of TTY / Serial patches for 5.7-rc1
 
 Lots of console fixups and reworking in here, serial core tweaks
 (doesn't that ever get old, why are we still creating new serial
 devices?), serial driver updates, line-protocol driver updates, and some
 vt cleanups and fixes included in here as well.
 
 All have been in linux-next with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here is the big set of TTY / Serial patches for 5.7-rc1

  Lots of console fixups and reworking in here, serial core tweaks
  (doesn't that ever get old, why are we still creating new serial
  devices?), serial driver updates, line-protocol driver updates, and
  some vt cleanups and fixes included in here as well.

  All have been in linux-next with no reported issues"

* tag 'tty-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (161 commits)
  serial: 8250: Optimize irq enable after console write
  serial: 8250: Fix rs485 delay after console write
  vt: vt_ioctl: fix use-after-free in vt_in_use()
  vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console
  tty: serial: make SERIAL_SPRD depend on COMMON_CLK
  tty: serial: fsl_lpuart: fix return value checking
  tty: serial: fsl_lpuart: move dma_request_chan()
  ARM: dts: tango4: Make /serial compatible with ns16550a
  ARM: dts: mmp*: Make the serial ports compatible with xscale-uart
  ARM: dts: mmp*: Fix serial port names
  ARM: dts: mmp2-brownstone: Don't redeclare phandle references
  ARM: dts: pxa*: Make the serial ports compatible with xscale-uart
  ARM: dts: pxa*: Fix serial port names
  ARM: dts: pxa*: Don't redeclare phandle references
  serial: omap: drop unused dt-bindings header
  serial: 8250: 8250_omap: Add DMA support for UARTs on K3 SoCs
  serial: 8250: 8250_omap: Work around errata causing spurious IRQs with DMA
  serial: 8250: 8250_omap: Extend driver data to pass FIFO trigger info
  serial: 8250: 8250_omap: Move locking out from __dma_rx_do_complete()
  serial: 8250: 8250_omap: Account for data in flight during DMA teardown
  ...
2020-03-31 16:18:55 -07:00
Rafael J. Wysocki 8f1073ed8c Merge branch 'pm-qos'
* pm-qos: (30 commits)
  PM: QoS: annotate data races in pm_qos_*_value()
  Documentation: power: fix pm_qos_interface.rst format warning
  PM: QoS: Make CPU latency QoS depend on CONFIG_CPU_IDLE
  Documentation: PM: QoS: Update to reflect previous code changes
  PM: QoS: Update file information comments
  PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY and rename related functions
  sound: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: usb: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: tty: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: spi: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: net: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: mmc: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: media: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: hsi: Call cpu_latency_qos_*() instead of pm_qos_*()
  drm: i915: Call cpu_latency_qos_*() instead of pm_qos_*()
  x86: platform: iosf_mbi: Call cpu_latency_qos_*() instead of pm_qos_*()
  cpuidle: Call cpu_latency_qos_limit() instead of pm_qos_request()
  PM: QoS: Add CPU latency QoS API wrappers
  PM: QoS: Adjust pm_qos_request() signature and reorder pm_qos.h
  PM: QoS: Simplify definitions of CPU latency QoS trace events
  ...
2020-03-30 14:45:57 +02:00
Lukas Wunner 8d5b305484 serial: 8250: Optimize irq enable after console write
Commit 7f9803072f ("serial: 8250: Support console on software emulated
rs485 ports") amended serial8250_console_write() with rs485 support, but
positioned the invocation of ->rs485_stop_tx() after re-enablement of
interrupts.  The irq handler and ->console_write() are serialized with
the port spinlock, so no problem there, but due to the rs485 delay, the
irq handler may unnecessarily spin for a while.  Avoid that by moving
->rs485_stop_tx() before re-enablement of interrupts, which also mirrors
the order at the beginning of serial8250_console_write().

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/019839cb1f61b01210b6ff9ac9f9079ca77f8411.1585319447.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-27 15:45:54 +01:00
Lukas Wunner 4e36f94e99 serial: 8250: Fix rs485 delay after console write
Due to a silly copy-paste mistake, commit 7f9803072f ("serial: 8250:
Support console on software emulated rs485 ports") erroneously pauses
for the duration of delay_rts_before_send after writing to the console,
instead of delay_rts_after_send.  Mea culpa.

Fixes: 7f9803072f ("serial: 8250: Support console on software emulated rs485 ports")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/9dd67f33c90d23f7fafa3b81b1e812ddabf9ca24.1585319447.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-27 15:45:54 +01:00
Eric Biggers 7cf64b18b0 vt: vt_ioctl: fix use-after-free in vt_in_use()
vt_in_use() dereferences console_driver->ttys[i] without proper locking.
This is broken because the tty can be closed and freed concurrently.

We could fix this by using 'READ_ONCE(console_driver->ttys[i]) != NULL'
and skipping the check of tty_struct::count.  But, looking at
console_driver->ttys[i] isn't really appropriate anyway because even if
it is NULL the tty can still be in the process of being closed.

Instead, fix it by making vt_in_use() require console_lock() and check
whether the vt is allocated and has port refcount > 1.  This works since
following the patch "vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use
virtual console" the port refcount is incremented while the vt is open.

Reproducer (very unreliable, but it worked for me after a few minutes):

	#include <fcntl.h>
	#include <linux/vt.h>

	int main()
	{
		int fd, nproc;
		struct vt_stat state;
		char ttyname[16];

		fd = open("/dev/tty10", O_RDONLY);
		for (nproc = 1; nproc < 8; nproc *= 2)
			fork();
		for (;;) {
			sprintf(ttyname, "/dev/tty%d", rand() % 8);
			close(open(ttyname, O_RDONLY));
			ioctl(fd, VT_GETSTATE, &state);
		}
	}

KASAN report:

	BUG: KASAN: use-after-free in vt_in_use drivers/tty/vt/vt_ioctl.c:48 [inline]
	BUG: KASAN: use-after-free in vt_ioctl+0x1ad3/0x1d70 drivers/tty/vt/vt_ioctl.c:657
	Read of size 4 at addr ffff888065722468 by task syz-vt2/132

	CPU: 0 PID: 132 Comm: syz-vt2 Not tainted 5.6.0-rc5-00130-g089b6d3654916 #13
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014
	Call Trace:
	 [...]
	 vt_in_use drivers/tty/vt/vt_ioctl.c:48 [inline]
	 vt_ioctl+0x1ad3/0x1d70 drivers/tty/vt/vt_ioctl.c:657
	 tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660
	 [...]

	Allocated by task 136:
	 [...]
	 kzalloc include/linux/slab.h:669 [inline]
	 alloc_tty_struct+0x96/0x8a0 drivers/tty/tty_io.c:2982
	 tty_init_dev+0x23/0x350 drivers/tty/tty_io.c:1334
	 tty_open_by_driver drivers/tty/tty_io.c:1987 [inline]
	 tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035
	 [...]

	Freed by task 41:
	 [...]
	 kfree+0xbf/0x200 mm/slab.c:3757
	 free_tty_struct+0x8d/0xb0 drivers/tty/tty_io.c:177
	 release_one_tty+0x22d/0x2f0 drivers/tty/tty_io.c:1468
	 process_one_work+0x7f1/0x14b0 kernel/workqueue.c:2264
	 worker_thread+0x8b/0xc80 kernel/workqueue.c:2410
	 [...]

Fixes: 4001d7b7fc ("vt: push down the tty lock so we can see what is left to tackle")
Cc: <stable@vger.kernel.org> # v3.4+
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200322034305.210082-3-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-27 12:35:04 +01:00
Eric Biggers ca4463bf84 vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console
The VT_DISALLOCATE ioctl can free a virtual console while tty_release()
is still running, causing a use-after-free in con_shutdown().  This
occurs because VT_DISALLOCATE considers a virtual console's
'struct vc_data' to be unused as soon as the corresponding tty's
refcount hits 0.  But actually it may be still being closed.

Fix this by making vc_data be reference-counted via the embedded
'struct tty_port'.  A newly allocated virtual console has refcount 1.
Opening it for the first time increments the refcount to 2.  Closing it
for the last time decrements the refcount (in tty_operations::cleanup()
so that it happens late enough), as does VT_DISALLOCATE.

Reproducer:
	#include <fcntl.h>
	#include <linux/vt.h>
	#include <sys/ioctl.h>
	#include <unistd.h>

	int main()
	{
		if (fork()) {
			for (;;)
				close(open("/dev/tty5", O_RDWR));
		} else {
			int fd = open("/dev/tty10", O_RDWR);

			for (;;)
				ioctl(fd, VT_DISALLOCATE, 5);
		}
	}

KASAN report:
	BUG: KASAN: use-after-free in con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278
	Write of size 8 at addr ffff88806a4ec108 by task syz_vt/129

	CPU: 0 PID: 129 Comm: syz_vt Not tainted 5.6.0-rc2 #11
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014
	Call Trace:
	 [...]
	 con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278
	 release_tty+0xa8/0x410 drivers/tty/tty_io.c:1514
	 tty_release_struct+0x34/0x50 drivers/tty/tty_io.c:1629
	 tty_release+0x984/0xed0 drivers/tty/tty_io.c:1789
	 [...]

	Allocated by task 129:
	 [...]
	 kzalloc include/linux/slab.h:669 [inline]
	 vc_allocate drivers/tty/vt/vt.c:1085 [inline]
	 vc_allocate+0x1ac/0x680 drivers/tty/vt/vt.c:1066
	 con_install+0x4d/0x3f0 drivers/tty/vt/vt.c:3229
	 tty_driver_install_tty drivers/tty/tty_io.c:1228 [inline]
	 tty_init_dev+0x94/0x350 drivers/tty/tty_io.c:1341
	 tty_open_by_driver drivers/tty/tty_io.c:1987 [inline]
	 tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035
	 [...]

	Freed by task 130:
	 [...]
	 kfree+0xbf/0x1e0 mm/slab.c:3757
	 vt_disallocate drivers/tty/vt/vt_ioctl.c:300 [inline]
	 vt_ioctl+0x16dc/0x1e30 drivers/tty/vt/vt_ioctl.c:818
	 tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660
	 [...]

Fixes: 4001d7b7fc ("vt: push down the tty lock so we can see what is left to tackle")
Cc: <stable@vger.kernel.org> # v3.4+
Reported-by: syzbot+522643ab5729b0421998@syzkaller.appspotmail.com
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200322034305.210082-2-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-27 12:35:04 +01:00
Chunyan Zhang 3b9c55efb2 tty: serial: make SERIAL_SPRD depend on COMMON_CLK
kbuild-test reported an error:

  config: mips-randconfig-a001-20200321 ...
  >> drivers/tty/serial/sprd_serial.c:1175: undefined reference
  to `clk_set_parent'

Because some mips Kconfig selects HAVE_CLK but not COMMON_CLK and no
clk_set_parent implemented, so the error was exposed. So adding
dependence on COMMON_CLK can fix this issue.

Fixes: 7ba87cfec7 ("tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20200325081427.20312-1-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-26 15:41:03 +01:00
Michael Walle d7c53fb081 tty: serial: fsl_lpuart: fix return value checking
The return value of lpuart_dma_tx_request() is an negative errno on
failure and zero on success.

Fixes: 159381df14 ("tty: serial: fsl_lpuart: fix DMA operation when using IOMMU")
Reported-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Fugang Duan <fugang.duan@nxp.com>
Link: https://lore.kernel.org/r/20200325090658.25967-2-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-26 15:34:05 +01:00
Michael Walle d0e7600b91 tty: serial: fsl_lpuart: move dma_request_chan()
Move dma_request_chan() out of the atomic context. First this call
should not be in the atomic context at all and second the
dev_info_once() may cause a hang because because the console takes this
spinlock, too.

Fixes: 159381df14 ("tty: serial: fsl_lpuart: fix DMA operation when using IOMMU")
Reported-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Fugang Duan <fugang.duan@nxp.com>
Tested-by: Leonard Crestez <leonard.crestez@nxp.com>
Link: https://lore.kernel.org/r/20200325090658.25967-1-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-26 15:34:05 +01:00
Uwe Kleine-König c97c65f36e serial: omap: drop unused dt-bindings header
The definitons in the dt-binding's gpio header only contains some
constants to be used in device trees. It is not relevant for omap-serial
(as the gpio API hides the details) and in fact unused so it can just be
dropped.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Link: https://lore.kernel.org/r/20200321204031.30369-1-uwe@kleine-koenig.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:26:11 +01:00
Vignesh Raghavendra c26389f998 serial: 8250: 8250_omap: Add DMA support for UARTs on K3 SoCs
UART on K3 SoCs has configurable RX timeout behavior (controlled via
EFR2) and better DMA integration. This allows to transfer as larger
amount data per DMA transfer compared to older SoCs.  Add support for
the same.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-7-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:11 +01:00
Vignesh Raghavendra c6689dfd87 serial: 8250: 8250_omap: Work around errata causing spurious IRQs with DMA
As per Advisory 27 of AM437x Silicon errata document, Spurious UART
interrupts may occur when DMA mode (FCR.DMA_MODE) is enabled. The
Interrupt Controller flags that a UART interrupt has occurred; however,
the associated IT_PENDING bit remains set to 1, indicating that no
interrupt is pending. Acknowledge the spurious interrupts for every
occurrence as workaround.

Errata is applicable to all TI SoCs with this IP.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-6-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:11 +01:00
Vignesh Raghavendra 7229b84c20 serial: 8250: 8250_omap: Extend driver data to pass FIFO trigger info
Although same 8250 compliant UART IP is reused across different SoC,
their integration wrt DMA varies greatly across SoCs. Therefore,
different SoC may need to use different FIFO trigger level for DMA
event and DMA configuration parameters. Provide a way to pass this
information via driver data. This is required to support UART DMA on
AM654/J721e SoCs.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-5-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:10 +01:00
Peter Ujfalusi 7898984167 serial: 8250: 8250_omap: Move locking out from __dma_rx_do_complete()
Caller functions of __dma_rx_do_complete() already hold rx_dma_lock.
Therefore move locking out of the function to avoid need to release and
reacquire lock.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-4-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:10 +01:00
Vignesh Raghavendra 4bcf59a5de serial: 8250: 8250_omap: Account for data in flight during DMA teardown
Take into account data stuck in DMA internal buffers before pushing data
to higher layer. dma_tx_state has "in_flight_bytes" member that provides
this information.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-3-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:10 +01:00
Vignesh Raghavendra 7cf4df30a9 serial: 8250: 8250_omap: Terminate DMA before pushing data on RX timeout
Terminate and flush DMA internal buffers, before pushing RX data to
higher layer. Otherwise, this will lead to data corruption, as driver
would end up pushing stale buffer data to higher layer while actual data
is still stuck inside DMA hardware and has yet not arrived at the
memory.
While at that, replace deprecated dmaengine_terminate_all() with
dmaengine_terminate_async().

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-2-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:10 +01:00
Peter Ujfalusi 4ce35a3617 serial: 8250_omap: Fix sleeping function called from invalid context during probe
When booting j721e the following bug is printed:

[    1.154821] BUG: sleeping function called from invalid context at kernel/sched/completion.c:99
[    1.154827] in_atomic(): 0, irqs_disabled(): 128, non_block: 0, pid: 12, name: kworker/0:1
[    1.154832] 3 locks held by kworker/0:1/12:
[    1.154836]  #0: ffff000840030728 ((wq_completion)events){+.+.}, at: process_one_work+0x1d4/0x6e8
[    1.154852]  #1: ffff80001214fdd8 (deferred_probe_work){+.+.}, at: process_one_work+0x1d4/0x6e8
[    1.154860]  #2: ffff00084060b170 (&dev->mutex){....}, at: __device_attach+0x38/0x138
[    1.154872] irq event stamp: 63096
[    1.154881] hardirqs last  enabled at (63095): [<ffff800010b74318>] _raw_spin_unlock_irqrestore+0x70/0x78
[    1.154887] hardirqs last disabled at (63096): [<ffff800010b740d8>] _raw_spin_lock_irqsave+0x28/0x80
[    1.154893] softirqs last  enabled at (62254): [<ffff800010080c88>] _stext+0x488/0x564
[    1.154899] softirqs last disabled at (62247): [<ffff8000100fdb3c>] irq_exit+0x114/0x140
[    1.154906] CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.6.0-rc6-next-20200318-00094-g45e4089b0bd3 #221
[    1.154911] Hardware name: Texas Instruments K3 J721E SoC (DT)
[    1.154917] Workqueue: events deferred_probe_work_func
[    1.154923] Call trace:
[    1.154928]  dump_backtrace+0x0/0x190
[    1.154933]  show_stack+0x14/0x20
[    1.154940]  dump_stack+0xe0/0x148
[    1.154946]  ___might_sleep+0x150/0x1f0
[    1.154952]  __might_sleep+0x4c/0x80
[    1.154957]  wait_for_completion_timeout+0x40/0x140
[    1.154964]  ti_sci_set_device_state+0xa0/0x158
[    1.154969]  ti_sci_cmd_get_device_exclusive+0x14/0x20
[    1.154977]  ti_sci_dev_start+0x34/0x50
[    1.154984]  genpd_runtime_resume+0x78/0x1f8
[    1.154991]  __rpm_callback+0x3c/0x140
[    1.154996]  rpm_callback+0x20/0x80
[    1.155001]  rpm_resume+0x568/0x758
[    1.155007]  __pm_runtime_resume+0x44/0xb0
[    1.155013]  omap8250_probe+0x2b4/0x508
[    1.155019]  platform_drv_probe+0x50/0xa0
[    1.155023]  really_probe+0xd4/0x318
[    1.155028]  driver_probe_device+0x54/0xe8
[    1.155033]  __device_attach_driver+0x80/0xb8
[    1.155039]  bus_for_each_drv+0x74/0xc0
[    1.155044]  __device_attach+0xdc/0x138
[    1.155049]  device_initial_probe+0x10/0x18
[    1.155053]  bus_probe_device+0x98/0xa0
[    1.155058]  deferred_probe_work_func+0x74/0xb0
[    1.155063]  process_one_work+0x280/0x6e8
[    1.155068]  worker_thread+0x48/0x430
[    1.155073]  kthread+0x108/0x138
[    1.155079]  ret_from_fork+0x10/0x18

To fix the bug we need to first call pm_runtime_enable() prior to any
pm_runtime calls.

Reported-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20200320125200.6772-1-peter.ujfalusi@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:09 +01:00
Vignesh Raghavendra f4b042a050 serial: 8250: 8250_omap: Fix throttle to call stop_rx()
Call stop_rx() to halt reception when throttle is requested. Update
unthrottle callback to restart reception.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319103230.16867-3-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:09 +01:00
Vignesh Raghavendra f19c3f6c81 serial: 8250_port: Don't service RX FIFO if throttled
When port's throttle callback is called, it should stop pushing any more
data into TTY buffer to avoid buffer overflow. This means driver has to
stop HW from receiving more data and assert the HW flow control. For
UARTs with auto HW flow control (such as 8250_omap) manual assertion of
flow control line is not possible and only way is to allow RX FIFO to
fill up, thus trigger auto HW flow control logic.

Therefore make sure that 8250 generic IRQ handler does not drain data
when port is stopped (i.e UART_LSR_DR is unset in read_status_mask). Not
servicing, RX FIFO would trigger auto HW flow control when FIFO
occupancy reaches preset threshold, thus halting RX.
Since, error conditions in UART_LSR register are cleared just by reading
the register, data has to be drained in case there are FIFO errors, else
error information will lost.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319103230.16867-2-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:09 +01:00
Raviteja Narayanam 706bbc572d serial: uartps: Add TACTIVE check in cdns_uart_tx_empty function
Make sure that all bytes are transmitted out of Uart by monitoring
CDNS_UART_SR_TACTIVE bit as well.

Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com>
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Acked-by: Maarten Brock <m.brock@vanmierlo.com>
Link: https://lore.kernel.org/r/e2514818af5973be291cc117d07739f068b71639.1584610774.git.shubhrajyoti.datta@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:23:04 +01:00
Raviteja Narayanam 97451855cc serial: uartps: Remove unconditional wait inside set_termios
set_termios function should not wait for the transmit FIFO empty
(CDNS_UART_SR_TXEMPTY) unconditionally. The tty layer takes care
of it based on the parameter passed (TCSANOW/TCSADRAIN/TCSAFLUSH).

Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com>
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Link: https://lore.kernel.org/r/536e190dd5bbb474007a67e6323c048288942a28.1584610774.git.shubhrajyoti.datta@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:23:03 +01:00
Greg Kroah-Hartman cbf580ff09 Merge 5.6-rc7 into tty-next
We need the tty fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-23 08:02:55 +01:00
Greg Kroah-Hartman baca54d956 Merge 5.6-rc7 into char-misc-next
We need the char/misc driver fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-23 07:59:38 +01:00
Eric Biggers 6e622cd8bd tty: fix compat TIOCGSERIAL checking wrong function ptr
Commit 7765435030 ("take compat TIOC[SG]SERIAL treatment into
tty_compat_ioctl()") changed the compat version of TIOCGSERIAL to start
checking for the presence of the ->set_serial function pointer rather
than ->get_serial.  This appears to be a copy-and-paste error, since
->get_serial is the function pointer that is called as well as the
pointer that is checked by the non-compat version of TIOCGSERIAL.

Fix this by checking the correct function pointer.

Fixes: 7765435030 ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()")
Cc: <stable@vger.kernel.org> # v4.20+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200224182044.234553-3-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 13:15:13 +01:00
Eric Biggers 17329563a9 tty: fix compat TIOCGSERIAL leaking uninitialized memory
Commit 7765435030 ("take compat TIOC[SG]SERIAL treatment into
tty_compat_ioctl()") changed the compat version of TIOCGSERIAL to start
copying a whole 'serial_struct32' to userspace rather than individual
fields, but failed to initialize all padding and fields -- namely the
hole after the 'iomem_reg_shift' field, and the 'reserved' field.

Fix this by initializing the struct to zero.

[v2: use sizeof, and convert the adjacent line for consistency.]

Reported-by: syzbot+8da9175e28eadcb203ce@syzkaller.appspotmail.com
Fixes: 7765435030 ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()")
Cc: <stable@vger.kernel.org> # v4.20+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200224182044.234553-2-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 13:15:13 +01:00
Eric Biggers ed069827ca tty: drop outdated comments about release_tty() locking
The current version of the TTY code unlocks the tty_struct(s) before
release_tty() rather than after.  Moreover, tty_unlock_pair() no longer
exists.  Thus, remove the outdated comments regarding tty_unlock_pair().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200224073359.292795-1-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 13:08:45 +01:00
Nishad Kamdar db1032f7e4 tty: n_tracesink: Use the correct style for SPDX License Identifier
This patch corrects the SPDX License Identifier style in
header file related to Kernel driver API to route trace data.
For C header files Documentation/process/license-rules.rst
mandates C-like comments (opposed to C source files where
C++ style should be used).

Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Link: https://lore.kernel.org/r/20200302143642.GA3335@nishad
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 13:01:31 +01:00
Nishad Kamdar bdc3070e3f tty: hvc: Use the correct style for SPDX License Identifier
This patch corrects the SPDX License Identifier style in
header file related to the HVC driver.
For C header files Documentation/process/license-rules.rst
mandates C-like comments (opposed to C source files where
C++ style should be used).

Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Link: https://lore.kernel.org/r/20200301170419.GA7125@nishad
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 13:01:05 +01:00
Takashi Iwai caa47cc639 tty: nozomi: Use scnprintf() for avoiding potential buffer overflow
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Also rewrite the code in a standard if-form instead of ugly
conditional operators.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20200311092905.24362-1-tiwai@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 12:59:29 +01:00
Takashi Iwai e39c0ffe8c tty: serial: pch_uart: Use scnprintf() for avoiding potential buffer overflow
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20200311092930.24433-1-tiwai@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 12:59:29 +01:00
Alexandre Belloni e2c2e79871 tty: nozomi: fix spelling mistake "reserverd" -> "reserved"
The reserved bits should be named reserved.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200214141455.20902-1-alexandre.belloni@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 12:59:29 +01:00
Chunyan Zhang 7253407747 serial: sprd: remove redundant sprd_port cleanup
We don't need to cleanup sprd_port anymore, since we've dropped the way
of using the sprd_port[] array to get port index.

Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20200318105049.19623-3-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 12:20:04 +01:00
Chunyan Zhang 4b7349cb4e serial: sprd: getting port index via serial aliases only
This patch simplifies the process of getting serial port number, with
this patch, serial devices must have aliases configured in devicetree.

The serial port searched out via sprd_port array maybe wrong if we don't
have serial alias defined in devicetree, and specify console with command
line, we would get the wrong port number if other serial ports probe
failed before console's. So using aliases is mandatory.

Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20200318105049.19623-2-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 12:20:04 +01:00
Vincent Chen 630db5cbc7 tty: serial: Add CONSOLE_POLL support to SiFive UART
Add CONSOLE_POLL support for future KGDB porting.

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>

Changes since v1:
1. Fix the compile error reported by kbuild test robot
Link: https://lore.kernel.org/r/1584492027-23236-1-git-send-email-vincent.chen@sifive.com

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 11:07:13 +01:00
Andy Shevchenko 089b6d3654 serial: 8250_port: Disable DMA operations for kernel console
It would be too tricky and error prone to allow DMA operations on
kernel console.

One of the concern is when DMA is a separate device, for example on
Intel CherryTrail platforms, and might need special work around to be
functional, see the commit

  eebb3e8d8a ("ACPI / LPSS: override power state for LPSS DMA device")

for more information.

Another one is that kernel console is used in atomic context, e.g.
when printing crucial information to the user (Oops or crash),
and DMA may not serve due to power management complications
including non-atomic ACPI calls but not limited to it (see above).

Besides that, other concerns are described in the commit

  84b40e3b57 ("serial: 8250: omap: Disable DMA for console UART")

done for OMAP UART and may be repeated here.

Disable any kind of DMA operations on kernel console due to above concerns.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200217114016.49856-7-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:58:00 +01:00
Andy Shevchenko bedb404e91 serial: 8250_port: Don't use power management for kernel console
Doing any kind of power management for kernel console is really bad idea.

First of all, it runs in poll and atomic mode. This fact attaches a limitation
on the functions that might be called. For example, pm_runtime_get_sync() might
sleep and thus can't be used. This call needs, for example, to bring the device
to powered on state on the system, where the power on sequence may require
on-atomic operations, such as Intel Cherrytrail with ACPI enumerated UARTs.
That said, on ACPI enabled platforms it might even call firmware for a job.

On the other hand pm_runtime_get() doesn't guarantee that device will become
powered on fast enough.

Besides that, imagine the case when console is about to print a kernel Oops and
it's powered off. In such an emergency case calling the complex functions is
not the best what we can do, taking into consideration that user wants to see
at least something of the last kernel word before it passes away.

Here we modify the 8250 console code to prevent runtime power management.

Note, there is a behaviour change for OMAP boards. It will require to detach
kernel console to become idle.

Link: https://lists.openwall.net/linux-kernel/2018/09/29/65
Suggested-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200217114016.49856-6-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:58:00 +01:00
Andy Shevchenko a3cb39d258 serial: core: Allow detach and attach serial device for console
In the future we would like to disable power management on the serial devices
used as kernel consoles to avoid weird behaviour in some cases. However,
disabling PM may prevent system to go to deep sleep states, which in its turn
leads to the higher power consumption.

Tony Lindgren proposed a work around, i.e. allow user to detach such consoles
to make PM working again. In case user wants to see what's going on, it also
provides a mechanism to attach console back.

Link: https://lists.openwall.net/linux-kernel/2018/09/29/65
Suggested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200217114016.49856-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:57:59 +01:00
Geert Uytterhoeven 7e13d0a6b1 Revert "tty: serial: samsung_tty: build it for any platform"
This reverts commit 175b558d0e.

When the user configures a kernel without support for Samsung SoCs, it
makes no sense to ask the user about enabling "Samsung SoC serial
support", as Samsung serial ports can only be found on Samsung SoCs.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200306102301.16870-1-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:22:23 +01:00
Lanqing Liu efc176929a serial: sprd: Fix a dereference warning
We should validate if the 'sup' is NULL or not before freeing DMA
memory, to fix below warning.

"drivers/tty/serial/sprd_serial.c:1141 sprd_remove()
 error: we previously assumed 'sup' could be null (see line 1132)"

Fixes: f4487db58e ("serial: sprd: Add DMA mode support")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Lanqing Liu <liuhhome@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/e2bd92691538e95b04a2c2a728f3292e1617018f.1584325957.git.liuhhome@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:20:41 +01:00
Chunyan Zhang f1b49d5a07 serial: sprd: remove __init from sprd_console_setup
The function sprd_console_setup() would be called from .probe() which can
be called after freeing __init functions, for example the .probe() would
return -EPROBE_DEFER since it depends on clock modules.

Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/20200316101930.9962-3-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:20:41 +01:00
Chunyan Zhang 72cc06be19 serial: sprd: check console via stdout-path in addition
The SPRD serial driver need to know which serial port would be used as
console in an early period during initialization, the purpose is to
keep the console port alive as possible even if there's some error
caused by no clock configured under serial devicetree nodes. But with
the patch [1], the console port couldn't be identified if missing
console command line.

So this patch adds using another interface to do check by reading
stdout-path.

[1] https://lore.kernel.org/lkml/20190826072929.7696-4-zhang.lyra@gmail.com/

Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/20200316101930.9962-2-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:20:41 +01:00
Stephen Rothwell 3670664b5d tty: evh_bytechan: Fix out of bounds accesses
ev_byte_channel_send() assumes that its third argument is a 16 byte
array. Some places where it is called it may not be (or we can't
easily tell if it is). Newer compilers have started producing warnings
about this, so make sure we actually pass a 16 byte array.

There may be more elegant solutions to this, but the driver is quite
old and hasn't been updated in many years.

The warnings (from a powerpc allyesconfig build) are:

  In file included from include/linux/byteorder/big_endian.h:5,
                   from arch/powerpc/include/uapi/asm/byteorder.h:14,
                   from include/asm-generic/bitops/le.h:6,
                   from arch/powerpc/include/asm/bitops.h:250,
                   from include/linux/bitops.h:29,
                   from include/linux/kernel.h:12,
                   from include/asm-generic/bug.h:19,
                   from arch/powerpc/include/asm/bug.h:109,
                   from include/linux/bug.h:5,
                   from include/linux/mmdebug.h:5,
                   from include/linux/gfp.h:5,
                   from include/linux/slab.h:15,
                   from drivers/tty/ehv_bytechan.c:24:
  drivers/tty/ehv_bytechan.c: In function ‘ehv_bc_udbg_putc’:
  arch/powerpc/include/asm/epapr_hcalls.h:298:20: warning: array subscript 1 is outside array bounds of ‘const char[1]’ [-Warray-bounds]
    298 |  r6 = be32_to_cpu(p[1]);
  include/uapi/linux/byteorder/big_endian.h:40:51: note: in definition of macro ‘__be32_to_cpu’
     40 | #define __be32_to_cpu(x) ((__force __u32)(__be32)(x))
        |                                                   ^
  arch/powerpc/include/asm/epapr_hcalls.h:298:7: note: in expansion of macro ‘be32_to_cpu’
    298 |  r6 = be32_to_cpu(p[1]);
        |       ^~~~~~~~~~~
  drivers/tty/ehv_bytechan.c:166:13: note: while referencing ‘data’
    166 | static void ehv_bc_udbg_putc(char c)
        |             ^~~~~~~~~~~~~~~~

Fixes: dcd83aaff1 ("tty/powerpc: introduce the ePAPR embedded hypervisor byte channel driver")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tested-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
[mpe: Trim warnings from change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200109183912.5fcb52aa@canb.auug.org.au
2020-03-17 23:40:31 +11:00
Jiri Slaby c3a834e87c vt: indent switch-case in setterm_command properly
Shift cases one level left. This makes the code more readable and some
lines need not wrap anymore.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200316065911.11024-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16 08:41:17 +01:00
Jiri Slaby f0e8e3da22 vt: selection, use rounddown() for start/endline computation
We have a helper called rounddown for these modulo computations. So use
it.

No functional change intended and "objdump -d" proves that.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200316065911.11024-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16 08:41:17 +01:00
Jiri Slaby 85af37056a vt: use min() to limit intervals
Instead of awkward ternary operator with comparison, use simple min()
for blankinterval and vesa_off_interval.

No functional change intended and "objdump -d" proves that.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200316065911.11024-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16 08:41:17 +01:00
Jiri Slaby b18d1c2efa tty: n_hdlc, remove FILE and LINE from pr_debug
As Joe suggests, dynamic debug can print module name and line number
along with message. So remove __FILE__ and __LINE__ from all those
pr_debug calls.

Out of curiosity, I measured the savings, 200 bytes of code are gone.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Suggested-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/20200316064910.4941-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16 08:39:47 +01:00
Jiri Slaby 5b30dee6cc vt: selection, fix double lock introduced by a merge
The merge commit cb05c6c82f (Merge 5.6-rc5 into tty-next) introduced a
double lock to set_selection_kernel. vc_sel.lock is locked both in
set_selection_kernel and its callee __set_selection_kernel now.

Remove the latter.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/r/20200316064544.4799-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16 08:39:47 +01:00
Douglas Anderson d49e7953f9 tty: serial: qcom_geni_serial: Don't try to manually disable the console
The geni serial driver's shutdown code had a special case to call
console_stop().  Grepping through the code, it was the only serial
driver doing something like this (the only other caller of
console_stop() was in serial_core.c).

As far as I can tell there's no reason to call console_stop() in the
geni code.  ...and a good reason _not_ to call it.  Specifically if
you have an agetty running on the same serial port as the console then
killing the agetty kills your console and if you start the agetty
again the console doesn't come back.

Fixes: c4f528795d ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200313134635.2.I3648fac6c98b887742934146ac2729ecb7232eb1@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-14 09:40:27 +01:00