Commit Graph

6439 Commits

Author SHA1 Message Date
Matthew Howell
5fdbe136ae serial: exar: Fix GPIO configuration for Sealevel cards based on XR17V35X
Sealevel XR17V35X based devices are inoperable on kernel versions
4.11 and above due to a change in the GPIO preconfiguration introduced in
commit
7dea8165f1. This patch fixes this by preconfiguring the GPIO on Sealevel
cards to the value (0x00) used prior to commit 7dea8165f1

With GPIOs preconfigured as per commit 7dea8165f1 all ports on
Sealevel XR17V35X based devices become stuck in high impedance
mode, regardless of dip-switch or software configuration. This
causes the device to become effectively unusable. This patch (in
various forms) has been distributed to our customers and no issues
related to it have been reported.

Fixes: 7dea8165f1 ("serial: exar: Preconfigure xr17v35x MPIOs as output")
Signed-off-by: Matthew Howell <matthew.howell@sealevel.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2007221605270.13247@tstest-VirtualBox
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-24 10:58:14 +02:00
Serge Semin
551e553f0d serial: 8250_mtk: Fix high-speed baud rates clamping
Commit 7b668c064e ("serial: 8250: Fix max baud limit in generic 8250
port") fixed limits of a baud rate setting for a generic 8250 port.
In other words since that commit the baud rate has been permitted to be
within [uartclk / 16 / UART_DIV_MAX; uartclk / 16], which is absolutely
normal for a standard 8250 UART port. But there are custom 8250 ports,
which provide extended baud rate limits. In particular the Mediatek 8250
port can work with baud rates up to "uartclk" speed.

Normally that and any other peculiarity is supposed to be handled in a
custom set_termios() callback implemented in the vendor-specific
8250-port glue-driver. Currently that is how it's done for the most of
the vendor-specific 8250 ports, but for some reason for Mediatek a
solution has been spread out to both the glue-driver and to the generic
8250-port code. Due to that a bug has been introduced, which permitted the
extended baud rate limit for all even for standard 8250-ports. The bug
has been fixed by the commit 7b668c064e ("serial: 8250: Fix max baud
limit in generic 8250 port") by narrowing the baud rates limit back down to
the normal bounds. Unfortunately by doing so we also broke the
Mediatek-specific extended bauds feature.

A fix of the problem described above is twofold. First since we can't get
back the extended baud rate limits feature to the generic set_termios()
function and that method supports only a standard baud rates range, the
requested baud rate must be locally stored before calling it and then
restored back to the new termios structure after the generic set_termios()
finished its magic business. By doing so we still use the
serial8250_do_set_termios() method to set the LCR/MCR/FCR/etc. registers,
while the extended baud rate setting procedure will be performed later in
the custom Mediatek-specific set_termios() callback. Second since a true
baud rate is now fully calculated in the custom set_termios() method we
need to locally update the port timeout by calling the
uart_update_timeout() function. After the fixes described above are
implemented in the 8250_mtk.c driver, the Mediatek 8250-port should
get back to normally working with extended baud rates.

Link: https://lore.kernel.org/linux-serial/20200701211337.3027448-1-danielwinkler@google.com

Fixes: 7b668c064e ("serial: 8250: Fix max baud limit in generic 8250 port")
Reported-by: Daniel Winkler <danielwinkler@google.com>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: stable <stable@vger.kernel.org>
Tested-by: Claire Chang <tientzu@chromium.org>
Link: https://lore.kernel.org/r/20200714124113.20918-1-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-21 21:23:18 +02:00
Yang Yingliang
f4c23a140d serial: 8250: fix null-ptr-deref in serial8250_start_tx()
I got null-ptr-deref in serial8250_start_tx():

[   78.114630] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[   78.123778] Mem abort info:
[   78.126560]   ESR = 0x86000007
[   78.129603]   EC = 0x21: IABT (current EL), IL = 32 bits
[   78.134891]   SET = 0, FnV = 0
[   78.137933]   EA = 0, S1PTW = 0
[   78.141064] user pgtable: 64k pages, 48-bit VAs, pgdp=00000027d41a8600
[   78.147562] [0000000000000000] pgd=00000027893f0003, p4d=00000027893f0003, pud=00000027893f0003, pmd=00000027c9a20003, pte=0000000000000000
[   78.160029] Internal error: Oops: 86000007 [#1] SMP
[   78.164886] Modules linked in: sunrpc vfat fat aes_ce_blk crypto_simd cryptd aes_ce_cipher crct10dif_ce ghash_ce sha2_ce sha256_arm64 sha1_ce ses enclosure sg sbsa_gwdt ipmi_ssif spi_dw_mmio sch_fq_codel vhost_net tun vhost vhost_iotlb tap ip_tables ext4 mbcache jbd2 ahci hisi_sas_v3_hw libahci hisi_sas_main libsas hns3 scsi_transport_sas hclge libata megaraid_sas ipmi_si hnae3 ipmi_devintf ipmi_msghandler br_netfilter bridge stp llc nvme nvme_core xt_sctp sctp libcrc32c dm_mod nbd
[   78.207383] CPU: 11 PID: 23258 Comm: null-ptr Not tainted 5.8.0-rc6+ #48
[   78.214056] Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2 CS V3.B210.01 03/12/2020
[   78.222888] pstate: 80400089 (Nzcv daIf +PAN -UAO BTYPE=--)
[   78.228435] pc : 0x0
[   78.230618] lr : serial8250_start_tx+0x160/0x260
[   78.235215] sp : ffff800062eefb80
[   78.238517] x29: ffff800062eefb80 x28: 0000000000000fff
[   78.243807] x27: ffff800062eefd80 x26: ffff202fd83b3000
[   78.249098] x25: ffff800062eefd80 x24: ffff202fd83b3000
[   78.254388] x23: ffff002fc5e50be8 x22: 0000000000000002
[   78.259679] x21: 0000000000000001 x20: 0000000000000000
[   78.264969] x19: ffffa688827eecc8 x18: 0000000000000000
[   78.270259] x17: 0000000000000000 x16: 0000000000000000
[   78.275550] x15: ffffa68881bc67a8 x14: 00000000000002e6
[   78.280841] x13: ffffa68881bc67a8 x12: 000000000000c539
[   78.286131] x11: d37a6f4de9bd37a7 x10: ffffa68881cccff0
[   78.291421] x9 : ffffa68881bc6000 x8 : ffffa688819daa88
[   78.296711] x7 : ffffa688822a0f20 x6 : ffffa688819e0000
[   78.302002] x5 : ffff800062eef9d0 x4 : ffffa68881e707a8
[   78.307292] x3 : 0000000000000000 x2 : 0000000000000002
[   78.312582] x1 : 0000000000000001 x0 : ffffa688827eecc8
[   78.317873] Call trace:
[   78.320312]  0x0
[   78.322147]  __uart_start.isra.9+0x64/0x78
[   78.326229]  uart_start+0xb8/0x1c8
[   78.329620]  uart_flush_chars+0x24/0x30
[   78.333442]  n_tty_receive_buf_common+0x7b0/0xc30
[   78.338128]  n_tty_receive_buf+0x44/0x2c8
[   78.342122]  tty_ioctl+0x348/0x11f8
[   78.345599]  ksys_ioctl+0xd8/0xf8
[   78.348903]  __arm64_sys_ioctl+0x2c/0xc8
[   78.352812]  el0_svc_common.constprop.2+0x88/0x1b0
[   78.357583]  do_el0_svc+0x44/0xd0
[   78.360887]  el0_sync_handler+0x14c/0x1d0
[   78.364880]  el0_sync+0x140/0x180
[   78.368185] Code: bad PC value

SERIAL_PORT_DFNS is not defined on each arch, if it's not defined,
serial8250_set_defaults() won't be called in serial8250_isa_init_ports(),
so the p->serial_in pointer won't be initialized, and it leads a null-ptr-deref.
Fix this problem by calling serial8250_set_defaults() after init uart port.

Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200721143852.4058352-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-21 21:23:18 +02:00
Johan Hovold
707631ce63 serial: tegra: drop bogus NULL tty-port checks
The struct tty_port is part of the uart state and will never be NULL in
the receive helpers. Drop the bogus NULL checks and rename the
pointer-variables "port" to differentiate them from struct tty_struct
pointers (which can be NULL).

Fixes: 962963e4ee ("serial: tegra: Switch to using struct tty_port")
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200710135947.2737-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-21 20:59:38 +02:00
Johan Hovold
b374c562ee serial: tegra: fix CREAD handling for PIO
Commit 33ae787b74 ("serial: tegra: add support to ignore read") added
support for dropping input in case CREAD isn't set, but for PIO the
ignore_status_mask wasn't checked until after the character had been
put in the receive buffer.

Note that the NULL tty-port test is bogus and will be removed by a
follow-on patch.

Fixes: 33ae787b74 ("serial: tegra: add support to ignore read")
Cc: stable <stable@vger.kernel.org>     # 5.4
Cc: Shardar Shariff Md <smohammed@nvidia.com>
Cc: Krishna Yarlagadda <kyarlagadda@nvidia.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200710135947.2737-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-21 20:58:25 +02:00
Helmut Grohne
22a82fa7d6 tty: xilinx_uartps: Really fix id assignment
The problems started with the revert (18cc7ac8a2). The
cdns_uart_console.index is statically assigned -1. When the port is
registered, Linux assigns consecutive numbers to it. It turned out that
when using ttyPS1 as console, the index is not updated as we are reusing
the same cdns_uart_console instance for multiple ports. When registering
ttyPS0, it gets updated from -1 to 0, but when registering ttyPS1, it
already is 0 and not updated.

That led to 2ae11c46d5. It assigns the index prior to registering
the uart_driver once. Unfortunately, that ended up breaking the
situation where the probe order does not match the id order. When using
the same device tree for both uboot and linux, it is important that the
serial0 alias points to the console. So some boards reverse those
aliases. This was reported by Jan Kiszka. The proposed fix was reverting
the index assignment and going back to the previous iteration.

However such a reversed assignement (serial0 -> uart1, serial1 -> uart0)
was already partially broken by the revert (18cc7ac8a2). While the
ttyPS device works, the kmsg connection is already broken and kernel
messages go missing. Reverting the id assignment does not fix this.

>From the xilinx_uartps driver pov (after reverting the refactoring
commits), there can be only one console. This manifests in static
variables console_pprt and cdns_uart_console. These variables are not
properly linked and can go out of sync. The cdns_uart_console.index is
important for uart_add_one_port. We call that function for each port -
one of which hopefully is the console. If it isn't, the CON_ENABLED flag
is not set and console_port is cleared. The next cdns_uart_probe call
then tries to register the next port using that same cdns_uart_console.

It is important that console_port and cdns_uart_console (and its index
in particular) stay in sync. The index assignment implemented by
Shubhrajyoti Datta is correct in principle. It just may have to happen a
second time if the first cdns_uart_probe call didn't encounter the
console device. And we shouldn't change the index once the console uart
is registered.

Reported-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Reported-by: Jan Kiszka <jan.kiszka@web.de>
Link: https://lore.kernel.org/linux-serial/f4092727-d8f5-5f91-2c9f-76643aace993@siemens.com/
Fixes: 18cc7ac8a2 ("Revert "serial: uartps: Register own uart console and driver structures"")
Fixes: 2ae11c46d5 ("tty: xilinx_uartps: Fix missing id assignment to the console")
Fixes: 76ed2e1057 ("Revert "tty: xilinx_uartps: Fix missing id assignment to the console"")
Signed-off-by: Helmut Grohne <helmut.grohne@intenta.de>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200713073227.GA3805@laureti-dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-21 18:12:03 +02:00
Tetsuo Handa
ce684552a2 vt: Reject zero-sized screen buffer size.
syzbot is reporting general protection fault in do_con_write() [1] caused
by vc->vc_screenbuf == ZERO_SIZE_PTR caused by vc->vc_screenbuf_size == 0
caused by vc->vc_cols == vc->vc_rows == vc->vc_size_row == 0 caused by
fb_set_var() from ioctl(FBIOPUT_VSCREENINFO) on /dev/fb0 , for
gotoxy(vc, 0, 0) from reset_terminal() from vc_init() from vc_allocate()
 from con_install() from tty_init_dev() from tty_open() on such console
causes vc->vc_pos == 0x10000000e due to
((unsigned long) ZERO_SIZE_PTR) + -1U * 0 + (-1U << 1).

I don't think that a console with 0 column or 0 row makes sense. And it
seems that vc_do_resize() does not intend to allow resizing a console to
0 column or 0 row due to

  new_cols = (cols ? cols : vc->vc_cols);
  new_rows = (lines ? lines : vc->vc_rows);

exception.

Theoretically, cols and rows can be any range as long as
0 < cols * rows * 2 <= KMALLOC_MAX_SIZE is satisfied (e.g.
cols == 1048576 && rows == 2 is possible) because of

  vc->vc_size_row = vc->vc_cols << 1;
  vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;

in visual_init() and kzalloc(vc->vc_screenbuf_size) in vc_allocate().

Since we can detect cols == 0 or rows == 0 via screenbuf_size = 0 in
visual_init(), we can reject kzalloc(0). Then, vc_allocate() will return
an error, and con_write() will not be called on a console with 0 column
or 0 row.

We need to make sure that integer overflow in visual_init() won't happen.
Since vc_do_resize() restricts cols <= 32767 and rows <= 32767, applying
1 <= cols <= 32767 and 1 <= rows <= 32767 restrictions to vc_allocate()
will be practically fine.

This patch does not touch con_init(), for returning -EINVAL there
does not help when we are not returning -ENOMEM.

[1] https://syzkaller.appspot.com/bug?extid=017265e8553724e514e8

Reported-and-tested-by: syzbot <syzbot+017265e8553724e514e8@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200712111013.11881-1-penguin-kernel@I-love.SAKURA.ne.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-21 18:07:15 +02:00
Linus Torvalds
7531ee3147 TTY/Serial driver fixes for 5.8-rc6
Here are some small tty and serial driver fixes for 5.8-rc6.
 
 The largest set of patches in here is a revert of the sysrq changes that
 went into 5.8-rc1 but turned out to cause a noticable overhead and cpu
 usage.
 
 Other than that, there's a few small serial driver fixes to resolve
 reported issues, and finally resolving the spinlock init problem on many
 serial driver consoles.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty into master

Pull tty/serial driver fixes from Greg KH:
 :Here are some small tty and serial driver fixes for 5.8-rc6.

  The largest set of patches in here is a revert of the sysrq changes
  that went into 5.8-rc1 but turned out to cause a noticable overhead
  and cpu usage.

  Other than that, there's a few small serial driver fixes to resolve
  reported issues, and finally resolving the spinlock init problem on
  many serial driver consoles.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-5.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: core: Initialise spin lock before use in uart_configure_port()
  serial: mxs-auart: add missed iounmap() in probe failure and remove
  serial: sh-sci: Initialize spinlock for uart console
  Revert "tty: xilinx_uartps: Fix missing id assignment to the console"
  serial: core: drop redundant sysrq checks
  serial: core: fix sysrq overhead regression
  Revert "serial: core: Refactor uart_unlock_and_check_sysrq()"
  tty/serial: fix serial_core.c kernel-doc warnings
  tty: serial: cpm_uart: Fix behaviour for non existing GPIOs
2020-07-16 11:10:27 -07:00
Andy Shevchenko
f743061a85 serial: core: Initialise spin lock before use in uart_configure_port()
The comment near to uart_port_spin_lock_init() says:

  Ensure that the serial console lock is initialised early.
  If this port is a console, then the spinlock is already initialised.

and there is nothing about enabled or disabled consoles. The commit
a3cb39d258 ("serial: core: Allow detach and attach serial device
for console") made a change, which follows the comment, and also to
prevent reinitialisation of the lock in use, when user detaches and
attaches back the same console device. But this change discovers
another issue, that uart_add_one_port() tries to access a spin lock
that now may be uninitialised. This happens when a driver expects
the serial core to register a console on its behalf. In this case
we must initialise a spin lock before use.

Fixes: a3cb39d258 ("serial: core: Allow detach and attach serial device for console")
Reported-by: Marc Zyngier <maz@kernel.org>
Reported-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: Anatoly Pugachev <matorola@gmail.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20200706214903.56148-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-10 14:44:46 +02:00
Chuhong Yuan
d8edf8eb5f serial: mxs-auart: add missed iounmap() in probe failure and remove
This driver calls ioremap() in probe, but it misses calling iounmap() in
probe's error handler and remove.
Add the missed calls to fix it.

Fixes: 47d37d6f94 ("serial: Add auart driver for i.MX23/28")
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200709135608.68290-1-hslester96@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-10 14:44:46 +02:00
Lad Prabhakar
f38278e9b8 serial: sh-sci: Initialize spinlock for uart console
serial core expects the spinlock to be initialized by the controller
driver for serial console, this patch makes sure the spinlock is
initialized, fixing the below issue:

[    0.865928] BUG: spinlock bad magic on CPU#0, swapper/0/1
[    0.865945]  lock: sci_ports+0x0/0x4c80, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
[    0.865955] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc1+ #112
[    0.865961] Hardware name: HopeRun HiHope RZ/G2H with sub board (DT)
[    0.865968] Call trace:
[    0.865979]  dump_backtrace+0x0/0x1d8
[    0.865985]  show_stack+0x14/0x20
[    0.865996]  dump_stack+0xe8/0x130
[    0.866006]  spin_dump+0x6c/0x88
[    0.866012]  do_raw_spin_lock+0xb0/0xf8
[    0.866023]  _raw_spin_lock_irqsave+0x80/0xa0
[    0.866032]  uart_add_one_port+0x3a4/0x4e0
[    0.866039]  sci_probe+0x504/0x7c8
[    0.866048]  platform_drv_probe+0x50/0xa0
[    0.866059]  really_probe+0xdc/0x330
[    0.866066]  driver_probe_device+0x58/0xb8
[    0.866072]  device_driver_attach+0x6c/0x90
[    0.866078]  __driver_attach+0x88/0xd0
[    0.866085]  bus_for_each_dev+0x74/0xc8
[    0.866091]  driver_attach+0x20/0x28
[    0.866098]  bus_add_driver+0x14c/0x1f8
[    0.866104]  driver_register+0x60/0x110
[    0.866109]  __platform_driver_register+0x40/0x48
[    0.866119]  sci_init+0x2c/0x34
[    0.866127]  do_one_initcall+0x88/0x428
[    0.866137]  kernel_init_freeable+0x2c0/0x328
[    0.866143]  kernel_init+0x10/0x108
[    0.866150]  ret_from_fork+0x10/0x18

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Fixes: a3cb39d258 ("serial: core: Allow detach and attach serial device for console")
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/1593618100-2151-1-git-send-email-prabhakar.mahadev-lad.rj@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-03 10:40:34 +02:00
Jan Kiszka
76ed2e1057 Revert "tty: xilinx_uartps: Fix missing id assignment to the console"
This reverts commit 2ae11c46d5.

It turned out to break the ultra96-rev1, e.g., which uses uart1 as
serial0 (and stdout-path = "serial0:115200n8").

Fixes: 2ae11c46d5 ("tty: xilinx_uartps: Fix missing id assignment to the console")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Link: https://lore.kernel.org/r/f4092727-d8f5-5f91-2c9f-76643aace993@siemens.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-27 16:16:37 +02:00
Johan Hovold
08d5470308 serial: core: fix sysrq overhead regression
Commit 8e20fc3917 ("serial_core: Move sysrq functions from header
file") converted the inline sysrq helpers to exported functions which
are now called for every received character, interrupt and break signal
also on systems without CONFIG_MAGIC_SYSRQ_SERIAL instead of being
optimised away by the compiler.

Inlining these helpers again also avoids the function call overhead when
CONFIG_MAGIC_SYSRQ_SERIAL is enabled (e.g. when the port is not used as
a console).

Fixes: 8e20fc3917 ("serial_core: Move sysrq functions from header file")
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Cc: stable <stable@vger.kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Link: https://lore.kernel.org/r/20200610152232.16925-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-27 16:16:37 +02:00
Johan Hovold
10652a9e9f Revert "serial: core: Refactor uart_unlock_and_check_sysrq()"
This reverts commit da9a5aa340.

In order to ease backporting a fix for a sysrq regression, revert this
rewrite which was since added on top.

The other sysrq helpers now bail out early when sysrq is not enabled;
it's better to keep that pattern here as well.

Note that the __releases() attribute won't be needed after the follow-on
fix either.

Fixes: da9a5aa340 ("serial: core: Refactor uart_unlock_and_check_sysrq()")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200610152232.16925-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-27 16:16:37 +02:00
Randy Dunlap
a71725619f tty/serial: fix serial_core.c kernel-doc warnings
Fix kernel-doc warnings in serial_core.c:

../drivers/tty/serial/serial_core.c:3300: warning: Function parameter or member 'port' not described in 'uart_get_rs485_mode'
../drivers/tty/serial/serial_core.c:3300: warning: Excess function parameter 'dev' description in 'uart_get_rs485_mode'
../drivers/tty/serial/serial_core.c:3300: warning: Excess function parameter 'rs485conf' description in 'uart_get_rs485_mode'

Fixes: c150c0f362 ("serial: Allow uart_get_rs485_mode() to return errno")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-serial@vger.kernel.org
Link: https://lore.kernel.org/r/e170db8e-5c8b-27ac-79a4-81b96ac0ca2d@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-27 13:56:39 +02:00
Christophe Leroy
311eab8d59 tty: serial: cpm_uart: Fix behaviour for non existing GPIOs
devm_gpiod_get_index() doesn't return NULL but -ENOENT when the
requested GPIO doesn't exist,  leading to the following messages:

[    2.742468] gpiod_direction_input: invalid GPIO (errorpointer)
[    2.748147] can't set direction for gpio #2: -2
[    2.753081] gpiod_direction_input: invalid GPIO (errorpointer)
[    2.758724] can't set direction for gpio #3: -2
[    2.763666] gpiod_direction_output: invalid GPIO (errorpointer)
[    2.769394] can't set direction for gpio #4: -2
[    2.774341] gpiod_direction_input: invalid GPIO (errorpointer)
[    2.779981] can't set direction for gpio #5: -2
[    2.784545] ff000a20.serial: ttyCPM1 at MMIO 0xfff00a20 (irq = 39, base_baud = 8250000) is a CPM UART

Use devm_gpiod_get_index_optional() instead.

At the same time, handle the error case and properly exit
with an error.

Fixes: 97cbaf2c82 ("tty: serial: cpm_uart: Convert to use GPIO descriptors")
Cc: stable@vger.kernel.org
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/694a25fdce548c5ee8b060ef6a4b02746b8f25c0.1591986307.git.christophe.leroy@csgroup.eu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-27 13:50:51 +02:00
Sumit Garg
5946d1f5b3 kdb: Switch to use safer dbg_io_ops over console APIs
In kgdb context, calling console handlers aren't safe due to locks used
in those handlers which could in turn lead to a deadlock. Although, using
oops_in_progress increases the chance to bypass locks in most console
handlers but it might not be sufficient enough in case a console uses
more locks (VT/TTY is good example).

Currently when a driver provides both polling I/O and a console then kdb
will output using the console. We can increase robustness by using the
currently active polling I/O driver (which should be lockless) instead
of the corresponding console. For several common cases (e.g. an
embedded system with a single serial port that is used both for console
output and debugger I/O) this will result in no console handler being
used.

In order to achieve this we need to reverse the order of preference to
use dbg_io_ops (uses polling I/O mode) over console APIs. So we just
store "struct console" that represents debugger I/O in dbg_io_ops and
while emitting kdb messages, skip console that matches dbg_io_ops
console in order to avoid duplicate messages. After this change,
"is_console" param becomes redundant and hence removed.

Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/1591264879-25920-5-git-send-email-sumit.garg@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-06-26 15:40:16 +01:00
Masahiro Yamada
a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
Michel Lespinasse
c1e8d7c6a7 mmap locking API: convert mmap_sem comments
Convert comments that reference mmap_sem to reference mmap_lock instead.

[akpm@linux-foundation.org: fix up linux-next leftovers]
[akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil]
[akpm@linux-foundation.org: more linux-next fixups, per Michel]

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Dmitry Safonov
9cb8f069de kernel: rename show_stack_loglvl() => show_stack()
Now the last users of show_stack() got converted to use an explicit log
level, show_stack_loglvl() can drop it's redundant suffix and become once
again well known show_stack().

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-51-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Dmitry Safonov
ab34b46d1a sysrq: use show_stack_loglvl()
Show the stack trace on a CPU with the same log level as "CPU%d" header.

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Link: http://lkml.kernel.org/r/20200418201944.482088-45-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:12 -07:00
Linus Torvalds
081096d98b TTY/Serial driver updates for 5.8-rc1
Here is the tty and serial driver updates for 5.8-rc1
 
 Nothing huge at all, just a lot of little serial driver fixes, updates
 for new devices and features, and other small things.  Full details are
 in the shortlog.
 
 Note, you will get a conflict merging with your tree in the
 Documentation/devicetree/bindings/serial/rs485.yaml file, but it should
 be pretty obvious what to do.  If not, I'm sure Rob will clean it all up
 afterwards :)
 
 All of these have been in linux-next with no issues for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here is the tty and serial driver updates for 5.8-rc1

  Nothing huge at all, just a lot of little serial driver fixes, updates
  for new devices and features, and other small things. Full details are
  in the shortlog.

  All of these have been in linux-next with no issues for a while"

* tag 'tty-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (67 commits)
  tty: serial: qcom_geni_serial: Add 51.2MHz frequency support
  tty: serial: imx: clear Ageing Timer Interrupt in handler
  serial: 8250_fintek: Add F81966 Support
  sc16is7xx: Add flag to activate IrDA mode
  dt-bindings: sc16is7xx: Add flag to activate IrDA mode
  serial: 8250: Support rs485 bus termination GPIO
  serial: 8520_port: Fix function param documentation
  dt-bindings: serial: Add binding for rs485 bus termination GPIO
  vt: keyboard: avoid signed integer overflow in k_ascii
  serial: 8250: Enable 16550A variants by default on non-x86
  tty: hvc_console, fix crashes on parallel open/close
  serial: imx: Initialize lock for non-registered console
  sc16is7xx: Read the LSR register for basic device presence check
  sc16is7xx: Allow sharing the IRQ line
  sc16is7xx: Use threaded IRQ
  sc16is7xx: Always use falling edge IRQ
  tty: n_gsm: Fix bogus i++ in gsm_data_kick
  tty: n_gsm: Remove unnecessary test in gsm_print_packet()
  serial: stm32: add no_console_suspend support
  tty: serial: fsl_lpuart: Use __maybe_unused instead of #if CONFIG_PM_SLEEP
  ...
2020-06-07 09:52:36 -07:00
Linus Torvalds
3925c3bbdf pci-v5.8-changes
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Merge tag 'pci-v5.8-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "Enumeration:

   - Program MPS for RCiEP devices (Ashok Raj)

   - Fix pci_register_host_bridge() device_register() error handling
     (Rob Herring)

   - Fix pci_host_bridge struct device release/free handling (Rob
     Herring)

  Resource management:

   - Allow resizing BARs for devices on root bus (Ard Biesheuvel)

  Power management:

   - Reduce Thunderbolt resume time by working around devices that don't
     support DLL Link Active reporting (Mika Westerberg)

   - Work around a Pericom USB controller OHCI/EHCI PME# defect
     (Kai-Heng Feng)

  Virtualization:

   - Add ACS quirk for Intel Root Complex Integrated Endpoints (Ashok
     Raj)

   - Avoid FLR for AMD Starship USB 3.0 (Kevin Buettner)

   - Avoid FLR for AMD Matisse HD Audio & USB 3.0 (Marcos Scriven)

  Error handling:

   - Use only _OSC (not HEST FIRMWARE_FIRST) to determine AER ownership
     (Alexandru Gagniuc, Kuppuswamy Sathyanarayanan)

   - Reduce verbosity by logging only ACPI_NOTIFY_DISCONNECT_RECOVER
     events (Kuppuswamy Sathyanarayanan)

   - Don't enable AER by default in Kconfig (Bjorn Helgaas)

  Peer-to-peer DMA:

   - Add AMD Zen Raven and Renoir Root Ports to whitelist (Alex Deucher)

  ASPM:

   - Allow ASPM on links to PCIe-to-PCI/PCI-X Bridges (Kai-Heng Feng)

  Endpoint framework:

   - Fix DMA channel release in test (Kunihiko Hayashi)

   - Add page size as argument to pci_epc_mem_init() (Lad Prabhakar)

   - Add support to handle multiple base for mapping outbound memory
     (Lad Prabhakar)

  Generic host bridge driver:

   - Support building as module (Rob Herring)

   - Eliminate pci_host_common_probe wrappers (Rob Herring)

  Amlogic Meson PCIe controller driver:

   - Don't use FAST_LINK_MODE to set up link (Marc Zyngier)

  Broadcom STB PCIe controller driver:

   - Disable ASPM L0s if 'aspm-no-l0s' in DT (Jim Quinlan)

   - Fix clk_put() error (Jim Quinlan)

   - Fix window register offset (Jim Quinlan)

   - Assert fundamental reset on initialization (Nicolas Saenz Julienne)

   - Add notify xHCI reset property (Nicolas Saenz Julienne)

   - Add init routine for Raspberry Pi 4 VL805 USB controller (Nicolas
     Saenz Julienne)

   - Sync with Raspberry Pi 4 firmware for VL805 initialization (Nicolas
     Saenz Julienne)

  Cadence PCIe controller driver:

   - Remove "cdns,max-outbound-regions" DT property (replaced by
     "ranges") (Kishon Vijay Abraham I)

   - Read 32-bit (not 16-bit) Vendor ID/Device ID property from DT
     (Kishon Vijay Abraham I)

  Marvell Aardvark PCIe controller driver:

   - Improve link training (Marek Behún)

   - Add PHY support (Marek Behún)

   - Add "phys", "max-link-speed", "reset-gpios" to dt-binding (Marek
     Behún)

   - Train link immediately after enabling training to work around
     detection issues with some cards (Pali Rohár)

   - Issue PERST via GPIO to work around detection issues (Pali Rohár)

   - Don't blindly enable ASPM L0s (Pali Rohár)

   - Replace custom macros by standard linux/pci_regs.h macros (Pali
     Rohár)

  Microsoft Hyper-V host bridge driver:

   - Fix probe failure path to release resource (Wei Hu)

   - Retry PCI bus D0 entry on invalid device state for kdump (Wei Hu)

  Renesas R-Car PCIe controller driver:

   - Fix incorrect programming of OB windows (Andrew Murray)

   - Add suspend/resume (Kazufumi Ikeda)

   - Rename pcie-rcar.c to pcie-rcar-host.c (Lad Prabhakar)

   - Add endpoint controller driver (Lad Prabhakar)

   - Fix PCIEPAMR mask calculation (Lad Prabhakar)

   - Add r8a77961 to DT binding (Yoshihiro Shimoda)

  Socionext UniPhier Pro5 controller driver:

   - Add endpoint controller driver (Kunihiko Hayashi)

  Synopsys DesignWare PCIe controller driver:

   - Program outbound ATU upper limit register (Alan Mikhak)

   - Fix inner MSI IRQ domain registration (Marc Zyngier)

  Miscellaneous:

   - Check for platform_get_irq() failure consistently (negative return
     means failure) (Aman Sharma)

   - Fix several runtime PM get/put imbalances (Dinghao Liu)

   - Use flexible-array and struct_size() helpers for code cleanup
     (Gustavo A. R. Silva)

   - Update & fix issues in bridge emulation of PCIe registers (Jon
     Derrick)

   - Add macros for bridge window names (PCI_BRIDGE_IO_WINDOW, etc)
     (Krzysztof Wilczyński)

   - Work around Intel PCH MROMs that have invalid BARs (Xiaochun Lee)"

* tag 'pci-v5.8-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (100 commits)
  PCI: uniphier: Add Socionext UniPhier Pro5 PCIe endpoint controller driver
  PCI: Add ACS quirk for Intel Root Complex Integrated Endpoints
  PCI/DPC: Print IRQ number used by port
  PCI/AER: Use "aer" variable for capability offset
  PCI/AER: Remove redundant dev->aer_cap checks
  PCI/AER: Remove redundant pci_is_pcie() checks
  PCI/AER: Remove HEST/FIRMWARE_FIRST parsing for AER ownership
  PCI: tegra: Fix runtime PM imbalance on error
  PCI: vmd: Filter resource type bits from shadow register
  PCI: tegra194: Fix runtime PM imbalance on error
  dt-bindings: PCI: Add UniPhier PCIe endpoint controller description
  PCI: hv: Use struct_size() helper
  PCI: Rename _DSM constants to align with spec
  PCI: Avoid FLR for AMD Starship USB 3.0
  PCI: Avoid FLR for AMD Matisse HD Audio & USB 3.0
  x86/PCI: Drop unused xen_register_pirq() gsi_override parameter
  PCI: dwc: Use private data pointer of "struct irq_domain" to get pcie_port
  PCI: amlogic: meson: Don't use FAST_LINK_MODE to set up link
  PCI: dwc: Fix inner MSI IRQ domain registration
  PCI: dwc: pci-dra7xx: Use devm_platform_ioremap_resource_byname()
  ...
2020-06-06 11:01:58 -07:00
Linus Torvalds
f1e455352b kgdb patches for 5.8-rc1
By far the biggest change in this cycle are the changes that allow much
 earlier debug of systems that are hooked up via UART by taking advantage
 of the earlycon framework to implement the kgdb I/O hooks before handing
 over to the regular polling I/O drivers once they are available. When
 discussing Doug's work we also found and fixed an broken
 raw_smp_processor_id() sequence in in_dbg_master().
 
 Also included are a collection of much smaller fixes and tweaks: a
 couple of tweaks to ged rid of doc gen or coccicheck warnings, future
 proof some internal calculations that made implicit power-of-2
 assumptions and eliminate some rather weird handling of magic
 environment variables in kdb.
 
 Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
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Merge tag 'kgdb-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux

Pull kgdb updates from Daniel Thompson:
 "By far the biggest change in this cycle are the changes that allow
  much earlier debug of systems that are hooked up via UART by taking
  advantage of the earlycon framework to implement the kgdb I/O hooks
  before handing over to the regular polling I/O drivers once they are
  available. When discussing Doug's work we also found and fixed an
  broken raw_smp_processor_id() sequence in in_dbg_master().

  Also included are a collection of much smaller fixes and tweaks: a
  couple of tweaks to ged rid of doc gen or coccicheck warnings, future
  proof some internal calculations that made implicit power-of-2
  assumptions and eliminate some rather weird handling of magic
  environment variables in kdb"

* tag 'kgdb-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
  kdb: Remove the misfeature 'KDBFLAGS'
  kdb: Cleanup math with KDB_CMD_HISTORY_COUNT
  serial: amba-pl011: Support kgdboc_earlycon
  serial: 8250_early: Support kgdboc_earlycon
  serial: qcom_geni_serial: Support kgdboc_earlycon
  serial: kgdboc: Allow earlycon initialization to be deferred
  Documentation: kgdboc: Document new kgdboc_earlycon parameter
  kgdb: Don't call the deinit under spinlock
  kgdboc: Disable all the early code when kgdboc is a module
  kgdboc: Add kgdboc_earlycon to support early kgdb using boot consoles
  kgdboc: Remove useless #ifdef CONFIG_KGDB_SERIAL_CONSOLE in kgdboc
  kgdb: Prevent infinite recursive entries to the debugger
  kgdb: Delay "kgdbwait" to dbg_late_init() by default
  kgdboc: Use a platform device to handle tty drivers showing up late
  Revert "kgdboc: disable the console lock when in kgdb"
  kgdb: Disable WARN_CONSOLE_UNLOCKED for all kgdb
  kgdb: Return true in kgdb_nmi_poll_knock()
  kgdb: Drop malformed kernel doc comment
  kgdb: Fix spurious true from in_dbg_master()
2020-06-03 14:57:03 -07:00
Sumit Garg
195867ffea serial: amba-pl011: Support kgdboc_earlycon
Implement the read() function in the early console driver. With
recently added kgdboc_earlycon feature, this allows you to use kgdb
to debug fairly early into the system boot.

We only bother implementing this if polling is enabled since kgdb can't
be enabled without that.

Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200507130644.v4.12.I8ee0811f0e0816dd8bfe7f2f5540b3dba074fae8@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-06-02 15:15:46 +01:00
Douglas Anderson
c5e7467d92 serial: 8250_early: Support kgdboc_earlycon
Implement the read() function in the early console driver.  With
recent kgdb patches this allows you to use kgdb to debug fairly early
into the system boot.

We only bother implementing this if polling is enabled since kgdb
can't be enabled without that.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20200507130644.v4.11.I8f668556c244776523320a95b09373a86eda11b7@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-06-02 15:15:46 +01:00
Douglas Anderson
205b5bdda2 serial: qcom_geni_serial: Support kgdboc_earlycon
Implement the read() function in the early console driver.  With
recent kgdb patches this allows you to use kgdb to debug fairly early
into the system boot.

We only bother implementing this if polling is enabled since kgdb
can't be enabled without that.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20200507130644.v4.10.If2deff9679a62c1ce1b8f2558a8635dc837adf8c@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-06-02 15:15:46 +01:00
Daniel Thompson
a4912303ac serial: kgdboc: Allow earlycon initialization to be deferred
Currently there is no guarantee that an earlycon will be initialized
before kgdboc tries to adopt it. Almost the opposite: on systems
with ACPI then if earlycon has no arguments then it is guaranteed that
earlycon will not be initialized.

This patch mitigates the problem by giving kgdboc_earlycon a second
chance during console_init(). This isn't quite as good as stopping during
early parameter parsing but it is still early in the kernel boot.

Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20200430161741.1832050-1-daniel.thompson@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
2020-06-02 15:15:45 +01:00
Douglas Anderson
1feb48baf2 kgdboc: Disable all the early code when kgdboc is a module
When kgdboc is compiled as a module all of the "ekgdboc" and
"kgdb_earlycon" code isn't useful and, in fact, breaks compilation.
This is because early_param() isn't defined for modules and that's how
this code gets configured.

It turns out that this was broken by commit eae3e19ca9 ("kgdboc:
Remove useless #ifdef CONFIG_KGDB_SERIAL_CONSOLE in kgdboc") and then
made worse by commit 220995622d ("kgdboc: Add kgdboc_earlycon to
support early kgdb using boot consoles").  I guess the #ifdef wasn't
so useless, even if it wasn't obvious why it was useful.  When kgdboc
was compiled as a module only "CONFIG_KGDB_SERIAL_CONSOLE_MODULE" was
defined, not "CONFIG_KGDB_SERIAL_CONSOLE".  That meant that the old
module.

Let's basically do the same thing that the old code (pre-removal of
the #ifdef) did but use "IS_BUILTIN(CONFIG_KGDB_SERIAL_CONSOLE)" to
make it more obvious what the point of the check is.  We'll fix
kgdboc_earlycon in a similar way.

Fixes: 220995622d ("kgdboc: Add kgdboc_earlycon to support early kgdb using boot consoles")
Fixes: eae3e19ca9 ("kgdboc: Remove useless #ifdef CONFIG_KGDB_SERIAL_CONSOLE in kgdboc")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200519084345.1.I91670accc8a5ddabab227eb63bb4ad3e2e9d2b58@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-06-02 15:15:45 +01:00
Linus Torvalds
e0cd920687 Merge branch 'uaccess.access_ok' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull uaccess/access_ok updates from Al Viro:
 "Removals of trivially pointless access_ok() calls.

  Note: the fiemap stuff was removed from the series, since they are
  duplicates with part of ext4 series carried in Ted's tree"

* 'uaccess.access_ok' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vmci_host: get rid of pointless access_ok()
  hfi1: get rid of pointless access_ok()
  usb: get rid of pointless access_ok() calls
  lpfc_debugfs: get rid of pointless access_ok()
  efi_test: get rid of pointless access_ok()
  drm_read(): get rid of pointless access_ok()
  via-pmu: don't bother with access_ok()
  drivers/crypto/ccp/sev-dev.c: get rid of pointless access_ok()
  omapfb: get rid of pointless access_ok() calls
  amifb: get rid of pointless access_ok() calls
  drivers/fpga/dfl-afu-dma-region.c: get rid of pointless access_ok()
  drivers/fpga/dfl-fme-pr.c: get rid of pointless access_ok()
  cm4000_cs.c cmm_ioctl(): get rid of pointless access_ok()
  nvram: drop useless access_ok()
  n_hdlc_tty_read(): remove pointless access_ok()
  tomoyo_write_control(): get rid of pointless access_ok()
  btrfs_ioctl_send(): don't bother with access_ok()
  fat_dir_ioctl(): hadn't needed that access_ok() for more than a decade...
  dlmfs_file_write(): get rid of pointless access_ok()
2020-06-01 16:09:43 -07:00
Al Viro
1a4b8febb6 n_hdlc_tty_read(): remove pointless access_ok()
only copy_to_user() is done to the address in question

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-05-29 11:03:03 -04:00
satya priya
a1b44ea340 tty: serial: qcom_geni_serial: Add 51.2MHz frequency support
To support BT use case over UART at baud rate of 3.2 Mbps,
we need SE clocks to run at 51.2MHz frequency. Previously this
frequency was not available in clk src, so, we were requesting
for 102.4 MHz and dividing it internally by 2 to get 51.2MHz.

As now 51.2MHz frequency is made available in clk src,
adding this frequency to UART frequency table.

We will save significant amount of power, if 51.2 is used
because it belongs to LowSVS range whereas 102.4 fall into
Nominal category.

Signed-off-by: satya priya <skakit@codeaurora.org>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/1590747282-5487-1-git-send-email-skakit@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-29 13:49:02 +02:00
Matthias Schiffer
d1d996afbd tty: serial: imx: clear Ageing Timer Interrupt in handler
The AGTIM flag must be cleared explicitly, otherwise the IRQ handler
will be called in an endless loop.

Fortunately, this issue currently doesn't affect mainline kernels in
practice, as the the RX FIFO trigger level is set to 1 in UFCR. When
setting the trigger level to a higher number, the issue is trivially
reproducible by any RX without DMA that doesn't fill the FIFO up to the
configured level.

Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Link: https://lore.kernel.org/r/20200528154747.14201-1-matthias.schiffer@ew.tq-group.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-29 13:00:54 +02:00
Ji-Ze Hong (Peter Hong)
423d9118c6 serial: 8250_fintek: Add F81966 Support
Fintek F81966 is a LPC/eSPI to 6 UARTs SuperIO. It has fully compatible
with F81866. It's also need check the IRQ mode with system assigned.

F81966 IRQ Mode setting:
        0xf0
                Bit1: IRQ_MODE0
                Bit0: Share mode (always on)
        0xf6
                Bit3: IRQ_MODE1

        Level/Low: IRQ_MODE0:0, IRQ_MODE1:0
        Edge/High: IRQ_MODE0:1, IRQ_MODE1:0

Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Cc: Ji-Ze Hong (Peter Hong) <peter_hong@fintek.com.tw>
Link: https://lore.kernel.org/r/20200528022429.32078-1-hpeter+linux_kernel@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-29 13:00:54 +02:00
Pascal Huerst
9eb90d57b5 sc16is7xx: Add flag to activate IrDA mode
This series of uart controllers is able to work in IrDA mode.
Add per-port flag to the device-tree to enable that feature if needed.

Signed-off-by: Pascal Huerst <pascal.huerst@gmail.com>
Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200529055058.1606910-3-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-29 12:42:56 +02:00
Lukas Wunner
d58a2df3d8 serial: 8250: Support rs485 bus termination GPIO
Commit e8759ad17d ("serial: uapi: Add support for bus termination")
introduced the ability to enable rs485 bus termination from user space.
So far the feature is only used by a single driver, 8250_exar.c, using a
hardcoded GPIO pin specific to Siemens IOT2040 products.

Provide for a more generic solution by allowing specification of an
rs485 bus termination GPIO pin in the device tree:  Amend the serial
core to retrieve the GPIO from the device tree (or ACPI table) and amend
the default ->rs485_config() callback for 8250 drivers to change the
GPIO on request from user space.

Perhaps 8250_exar.c can be converted to the generic approach in a
follow-up patch.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>
Link: https://lore.kernel.org/r/94c6c800d1ca9fa04766dd1d43a8272c5ad4bedd.1589811297.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-29 12:42:54 +02:00
Heiko Stuebner
f40a6be4a4 serial: 8520_port: Fix function param documentation
The parameter is named p while the documentation talks about up.
Fix the doc to be in line with the code.

Fixes: 058bc104f7 ("serial: 8250: Generalize rs485 software emulation")
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Heiko Stuebner <heiko.stuebner@theobroma-systems.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200517215610.2131618-2-heiko@sntech.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-29 12:42:54 +02:00
Dmitry Torokhov
b86dab0540 vt: keyboard: avoid signed integer overflow in k_ascii
When k_ascii is invoked several times in a row there is a potential for
signed integer overflow:

UBSAN: Undefined behaviour in drivers/tty/vt/keyboard.c:888:19 signed integer overflow:
10 * 1111111111 cannot be represented in type 'int'
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.6.11 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xce/0x128 lib/dump_stack.c:118
 ubsan_epilogue+0xe/0x30 lib/ubsan.c:154
 handle_overflow+0xdc/0xf0 lib/ubsan.c:184
 __ubsan_handle_mul_overflow+0x2a/0x40 lib/ubsan.c:205
 k_ascii+0xbf/0xd0 drivers/tty/vt/keyboard.c:888
 kbd_keycode drivers/tty/vt/keyboard.c:1477 [inline]
 kbd_event+0x888/0x3be0 drivers/tty/vt/keyboard.c:1495

While it can be worked around by using check_mul_overflow()/
check_add_overflow(), it is better to introduce a separate flag to
signal that number pad is being used to compose a symbol, and
change type of the accumulator from signed to unsigned, thus
avoiding undefined behavior when it overflows.

Reported-by: Kyungtae Kim <kt0755@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200525232740.GA262061@dtor-ws
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 12:21:44 +02:00
Josh Triplett
15a3f03d5e serial: 8250: Enable 16550A variants by default on non-x86
Some embedded devices still use these serial ports; make sure they're
still enabled by default on architectures more likely to have them, to
avoid rendering someone's console unavailable.

Reported-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reported-by: Maxim Kochetkov <fido_max@inbox.ru>
Fixes: dc56ecb81a ("serial: 8250: Support disabling mdelay-filled probes of 16550A variants")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Link: https://lore.kernel.org/r/a20b5fb7dd295cfb48160eecf4bdebd76332d67d.1590509426.git.josh@joshtriplett.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 10:55:36 +02:00
Jiri Slaby
24eb2377f9 tty: hvc_console, fix crashes on parallel open/close
hvc_open sets tty->driver_data to NULL when open fails at some point.
Typically, the failure happens in hp->ops->notifier_add(). If there is
a racing process which tries to open such mangled tty, which was not
closed yet, the process will crash in hvc_open as tty->driver_data is
NULL.

All this happens because close wants to know whether open failed or not.
But ->open should not NULL this and other tty fields for ->close to be
happy. ->open should call tty_port_set_initialized(true) and close
should check by tty_port_initialized() instead. So do this properly in
this driver.

So this patch removes these from ->open:
* tty_port_tty_set(&hp->port, NULL). This happens on last close.
* tty->driver_data = NULL. Dtto.
* tty_port_put(&hp->port). This happens in shutdown and until now, this
  must have been causing a reference underflow, if I am not missing
  something.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: stable <stable@vger.kernel.org>
Reported-and-tested-by: Raghavendra <rananta@codeaurora.org>
Link: https://lore.kernel.org/r/20200526145632.13879-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 10:55:36 +02:00
Andy Shevchenko
8f065acec7 serial: imx: Initialize lock for non-registered console
The commit a3cb39d258
("serial: core: Allow detach and attach serial device for console")
changed a bit logic behind lock initialization since for most of the console
driver it's supposed to have lock already initialized even if console is not
enabled. However, it's not the case for Freescale IMX console.

Initialize lock explicitly in the ->probe().

Note, there is still an open question should or shouldn't not this driver
register console properly.

Fixes: a3cb39d258 ("serial: core: Allow detach and attach serial device for console")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200525105952.13744-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-27 10:55:35 +02:00
Greg Kroah-Hartman
344235f557 Merge 5.7-rc7 into tty-next
We need the tty/serial fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-25 13:22:05 +02:00
Daniel Mack
2aa916e67d sc16is7xx: Read the LSR register for basic device presence check
Currently, the driver probes just fine and binds all its resources even
if the physical device is not present.

As the device lacks an identification register, let's at least read the
LSR register to check whether a device at the configured address responds
to the request at all.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200521091152.404404-7-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-22 11:06:15 +02:00
Daniel Mack
2d12fc792c sc16is7xx: Allow sharing the IRQ line
When the interrupt line is shared with other devices, the IRQ must be
level-triggered, as only one device can trigger a falling edge. To support
this, try to acquire the IRQ with IRQF_TRIGGER_LOW|IRQF_SHARED first.

Interrupt controllers that lack support for level-triggers will return an
error, in which case the driver will now retry the acqusition with
IRQF_TRIGGER_FALLING, which was also the default before.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200521091152.404404-6-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-22 11:06:14 +02:00
Daniel Mack
6393ff1c44 sc16is7xx: Use threaded IRQ
Use a threaded IRQ handler to get rid of the irq_work kthread.
This also allows for the driver to use interrupts generated by
a threaded controller.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200521091152.404404-5-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-22 11:05:46 +02:00
Daniel Mack
37f3965d74 sc16is7xx: Always use falling edge IRQ
The driver currently only uses IRQF_TRIGGER_FALLING if the probing
happened without a device-tree setup. The device however will always
generate falling edges on its IRQ line, so let's use that flag in
all cases.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Link: https://lore.kernel.org/r/20200521091152.404404-4-daniel@zonque.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-22 11:04:23 +02:00
Gregory CLEMENT
4dd31f1ffe tty: n_gsm: Fix bogus i++ in gsm_data_kick
When submitting the previous fix "tty: n_gsm: Fix waking up upper tty
layer when room available". It was suggested to switch from a while to
a for loop, but when doing it, there was a remaining bogus i++.

This patch removes this i++ and also reorganizes the code making it more
compact.

Fixes: e1eaea46bb ("tty: n_gsm line discipline")
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Link: https://lore.kernel.org/r/20200518084517.2173242-3-gregory.clement@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-19 16:19:54 +02:00
Gregory CLEMENT
57626ff1c9 tty: n_gsm: Remove unnecessary test in gsm_print_packet()
If the length is zero then the print_hex_dump_bytes won't output
anything, so testing the length before the call is unnecessary.

Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Link: https://lore.kernel.org/r/20200518084517.2173242-2-gregory.clement@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-19 16:19:54 +02:00
Erwan Le Ray
55484fcc50 serial: stm32: add no_console_suspend support
In order to display console messages in low power mode, console pins
must be kept active after suspend call.

Initial patch "serial: stm32: add support for no_console_suspend" was part
of "STM32 usart power improvement" series, but as dependancy to
console_suspend pinctl state has been removed to fit with Rob comment [1],
this patch has no more dependancy with any other patch of this series.

[1] https://lkml.org/lkml/2019/7/9/451

Signed-off-by: Erwan Le Ray <erwan.leray@st.com>

Link: https://lore.kernel.org/r/20200519094104.27082-1-erwan.leray@st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-19 15:53:36 +02:00
Douglas Anderson
220995622d kgdboc: Add kgdboc_earlycon to support early kgdb using boot consoles
We want to enable kgdb to debug the early parts of the kernel.
Unfortunately kgdb normally is a client of the tty API in the kernel
and serial drivers don't register to the tty layer until fairly late
in the boot process.

Serial drivers do, however, commonly register a boot console.  Let's
enable the kgdboc driver to work with boot consoles to provide early
debugging.

This change co-opts the existing read() function pointer that's part
of "struct console".  It's assumed that if a boot console (with the
flag CON_BOOT) has implemented read() that both the read() and write()
function are polling functions.  That means they work without
interrupts and read() will return immediately (with 0 bytes read) if
there's nothing to read.  This should be a safe assumption since it
appears that no current boot consoles implement read() right now and
there seems no reason to do so unless they wanted to support
"kgdboc_earlycon".

The normal/expected way to make all this work is to use
"kgdboc_earlycon" and "kgdboc" together.  You should point them both
to the same physical serial connection.  At boot time, as the system
transitions from the boot console to the normal console (and registers
a tty), kgdb will switch over.

One awkward part of all this, though, is that there can be a window
where the boot console goes away and we can't quite transtion over to
the main kgdboc that uses the tty layer.  There are two main problems:

1. The act of registering the tty doesn't cause any call into kgdboc
   so there is a window of time when the tty is there but kgdboc's
   init code hasn't been called so we can't transition to it.

2. On some serial drivers the normal console inits (and replaces the
   boot console) quite early in the system.  Presumably these drivers
   were coded up before earlycon worked as well as it does today and
   probably they don't need to do this anymore, but it causes us
   problems nontheless.

Problem #1 is not too big of a deal somewhat due to the luck of probe
ordering.  kgdboc is last in the tty/serial/Makefile so its probe gets
right after all other tty devices.  It's not fun to rely on this, but
it does work for the most part.

Problem #2 is a big deal, but only for some serial drivers.  Other
serial drivers end up registering the console (which gets rid of the
boot console) and tty at nearly the same time.

The way we'll deal with the window when the system has stopped using
the boot console and the time when we're setup using the tty is to
keep using the boot console.  This may sound surprising, but it has
been found to work well in practice.  If it doesn't work, it shouldn't
be too hard for a given serial driver to make it keep working.
Specifically, it's expected that the read()/write() function provided
in the boot console should be the same (or nearly the same) as the
normal kgdb polling functions.  That means continuing to use them
should work just fine.  To make things even more likely to work work
we'll also trap the recently added exit() function in the boot console
we're using and delay any calls to it until we're all done with the
boot console.

NOTE: there could be ways to use all this in weird / unexpected ways.
If you do something like this, it's a bit of a buyer beware situation.
Specifically:
- If you specify only "kgdboc_earlycon" but not "kgdboc" then
  (depending on your serial driver) things will probably work OK, but
  you'll get a warning printed the first time you use kgdb after the
  boot console is gone.  You'd only be able to do this, of course, if
  the serial driver you're running atop provided an early boot console.
- If your "kgdboc_earlycon" and "kgdboc" devices are not the same
  device things should work OK, but it'll be your job to switch over
  which device you're monitoring (including figuring out how to switch
  over gdb in-flight if you're using it).

When trying to enable "kgdboc_earlycon" it should be noted that the
names that are registered through the boot console layer and the tty
layer are not the same for the same port.  For example when debugging
on one board I'd need to pass "kgdboc_earlycon=qcom_geni
kgdboc=ttyMSM0" to enable things properly.  Since digging up the boot
console name is a pain and there will rarely be more than one boot
console enabled, you can provide the "kgdboc_earlycon" parameter
without specifying the name of the boot console.  In this case we'll
just pick the first boot that implements read() that we find.

This new "kgdboc_earlycon" parameter should be contrasted to the
existing "ekgdboc" parameter.  While both provide a way to debug very
early, the usage and mechanisms are quite different.  Specifically
"kgdboc_earlycon" is meant to be used in tandem with "kgdboc" and
there is a transition from one to the other.  The "ekgdboc" parameter,
on the other hand, replaces the "kgdboc" parameter.  It runs the same
logic as the "kgdboc" parameter but just relies on your TTY driver
being present super early.  The only known usage of the old "ekgdboc"
parameter is documented as "ekgdboc=kbd earlyprintk=vga".  It should
be noted that "kbd" has special treatment allowing it to init early as
a tty device.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/20200507130644.v4.8.I8fba5961bf452ab92350654aa61957f23ecf0100@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2020-05-18 17:49:27 +01:00