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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are a few small TTY/Serial/vt fixes for 5.9-rc3
Included in here are:
- qcom serial fixes
- vt ioctl and core bugfixes
- pl011 serial driver fixes
- 8250 serial driver fixes
- other misc serial driver fixes
and for good measure:
- fbcon fix for syzbot found problem.
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-5.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
tty: serial: imx: add dependence and build for earlycon
serial: samsung: Removes the IRQ not found warning
serial: 8250: change lock order in serial8250_do_startup()
serial: stm32: avoid kernel warning on absence of optional IRQ
serial: pl011: Fix oops on -EPROBE_DEFER
serial: pl011: Don't leak amba_ports entry on driver register error
serial: 8250_exar: Fix number of ports for Commtech PCIe cards
tty: serial: qcom_geni_serial: Drop __init from qcom_geni_console_setup
serial: qcom_geni_serial: Fix recent kdb hang
vt_ioctl: change VT_RESIZEX ioctl to check for error return from vc_resize()
fbcon: prevent user font height or width change from causing potential out-of-bounds access
vt: defer kfree() of vc_screenbuf in vc_do_resize()
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Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.
[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
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Add the earlycon dependence and add earlycon Makefile support
to allow to build the driver.
Fixes: 699cc4dfd140 ("tty: serial: imx: add imx earlycon driver")
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Link: https://lore.kernel.org/r/20200810060652.3436-1-fugang.duan@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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In few older Samsung SoCs like s3c2410, s3c2412
and s3c2440, UART IP is having 2 interrupt lines.
However, in other SoCs like s3c6400, s5pv210,
exynos5433, and exynos4210 UART is having only 1
interrupt line. Due to this, "platform_get_irq(platdev, 1)"
call in the driver gives the following false-positive error:
"IRQ index 1 not found" on newer SoC's.
This patch adds the condition to check for Tx interrupt
only for the those SoC's which have 2 interrupt lines.
Tested-by: Alim Akhtar <alim.akhtar@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Alim Akhtar <alim.akhtar@samsung.com>
Signed-off-by: Tamseel Shams <m.shams@samsung.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200810030021.45348-1-m.shams@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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We have a number of "uart.port->desc.lock vs desc.lock->uart.port"
lockdep reports coming from 8250 driver; this causes a bit of trouble
to people, so let's fix it.
The problem is reverse lock order in two different call paths:
chain #1:
serial8250_do_startup()
spin_lock_irqsave(&port->lock);
disable_irq_nosync(port->irq);
raw_spin_lock_irqsave(&desc->lock)
chain #2:
__report_bad_irq()
raw_spin_lock_irqsave(&desc->lock)
for_each_action_of_desc()
printk()
spin_lock_irqsave(&port->lock);
Fix this by changing the order of locks in serial8250_do_startup():
do disable_irq_nosync() first, which grabs desc->lock, and grab
uart->port after that, so that chain #1 and chain #2 have same lock
order.
Full lockdep splat:
======================================================
WARNING: possible circular locking dependency detected
5.4.39 #55 Not tainted
======================================================
swapper/0/0 is trying to acquire lock:
ffffffffab65b6c0 (console_owner){-...}, at: console_lock_spinning_enable+0x31/0x57
but task is already holding lock:
ffff88810a8e34c0 (&irq_desc_lock_class){-.-.}, at: __report_bad_irq+0x5b/0xba
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&irq_desc_lock_class){-.-.}:
_raw_spin_lock_irqsave+0x61/0x8d
__irq_get_desc_lock+0x65/0x89
__disable_irq_nosync+0x3b/0x93
serial8250_do_startup+0x451/0x75c
uart_startup+0x1b4/0x2ff
uart_port_activate+0x73/0xa0
tty_port_open+0xae/0x10a
uart_open+0x1b/0x26
tty_open+0x24d/0x3a0
chrdev_open+0xd5/0x1cc
do_dentry_open+0x299/0x3c8
path_openat+0x434/0x1100
do_filp_open+0x9b/0x10a
do_sys_open+0x15f/0x3d7
kernel_init_freeable+0x157/0x1dd
kernel_init+0xe/0x105
ret_from_fork+0x27/0x50
-> #1 (&port_lock_key){-.-.}:
_raw_spin_lock_irqsave+0x61/0x8d
serial8250_console_write+0xa7/0x2a0
console_unlock+0x3b7/0x528
vprintk_emit+0x111/0x17f
printk+0x59/0x73
register_console+0x336/0x3a4
uart_add_one_port+0x51b/0x5be
serial8250_register_8250_port+0x454/0x55e
dw8250_probe+0x4dc/0x5b9
platform_drv_probe+0x67/0x8b
really_probe+0x14a/0x422
driver_probe_device+0x66/0x130
device_driver_attach+0x42/0x5b
__driver_attach+0xca/0x139
bus_for_each_dev+0x97/0xc9
bus_add_driver+0x12b/0x228
driver_register+0x64/0xed
do_one_initcall+0x20c/0x4a6
do_initcall_level+0xb5/0xc5
do_basic_setup+0x4c/0x58
kernel_init_freeable+0x13f/0x1dd
kernel_init+0xe/0x105
ret_from_fork+0x27/0x50
-> #0 (console_owner){-...}:
__lock_acquire+0x118d/0x2714
lock_acquire+0x203/0x258
console_lock_spinning_enable+0x51/0x57
console_unlock+0x25d/0x528
vprintk_emit+0x111/0x17f
printk+0x59/0x73
__report_bad_irq+0xa3/0xba
note_interrupt+0x19a/0x1d6
handle_irq_event_percpu+0x57/0x79
handle_irq_event+0x36/0x55
handle_fasteoi_irq+0xc2/0x18a
do_IRQ+0xb3/0x157
ret_from_intr+0x0/0x1d
cpuidle_enter_state+0x12f/0x1fd
cpuidle_enter+0x2e/0x3d
do_idle+0x1ce/0x2ce
cpu_startup_entry+0x1d/0x1f
start_kernel+0x406/0x46a
secondary_startup_64+0xa4/0xb0
other info that might help us debug this:
Chain exists of:
console_owner --> &port_lock_key --> &irq_desc_lock_class
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&irq_desc_lock_class);
lock(&port_lock_key);
lock(&irq_desc_lock_class);
lock(console_owner);
*** DEADLOCK ***
2 locks held by swapper/0/0:
#0: ffff88810a8e34c0 (&irq_desc_lock_class){-.-.}, at: __report_bad_irq+0x5b/0xba
#1: ffffffffab65b5c0 (console_lock){+.+.}, at: console_trylock_spinning+0x20/0x181
stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.4.39 #55
Hardware name: XXXXXX
Call Trace:
<IRQ>
dump_stack+0xbf/0x133
? print_circular_bug+0xd6/0xe9
check_noncircular+0x1b9/0x1c3
__lock_acquire+0x118d/0x2714
lock_acquire+0x203/0x258
? console_lock_spinning_enable+0x31/0x57
console_lock_spinning_enable+0x51/0x57
? console_lock_spinning_enable+0x31/0x57
console_unlock+0x25d/0x528
? console_trylock+0x18/0x4e
vprintk_emit+0x111/0x17f
? lock_acquire+0x203/0x258
printk+0x59/0x73
__report_bad_irq+0xa3/0xba
note_interrupt+0x19a/0x1d6
handle_irq_event_percpu+0x57/0x79
handle_irq_event+0x36/0x55
handle_fasteoi_irq+0xc2/0x18a
do_IRQ+0xb3/0x157
common_interrupt+0xf/0xf
</IRQ>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Fixes: 768aec0b5bcc ("serial: 8250: fix shared interrupts issues with SMP and RT kernels")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: Raul Rangel <rrangel@google.com>
BugLink: https://bugs.chromium.org/p/chromium/issues/detail?id=1114800
Link: https://lore.kernel.org/lkml/CAHQZ30BnfX+gxjPm1DUd5psOTqbyDh4EJE=2=VAMW_VDafctkA@mail.gmail.com/T/#u
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200817022646.1484638-1-sergey.senozhatsky@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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stm32_init_port() of the stm32-usart may trigger a warning in
platform_get_irq() when the device tree specifies no wakeup interrupt.
The wakeup interrupt is usually a board-specific GPIO and the driver
functions correctly in its absence. The mainline stm32mp151.dtsi does
not specify it, so all mainline device trees trigger an unnecessary
kernel warning. Use of platform_get_irq_optional() avoids this.
Fixes: 2c58e56096dd ("serial: stm32: fix the get_irq error case")
Signed-off-by: Holger Assmann <h.assmann@pengutronix.de>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200813152757.32751-1-h.assmann@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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If probing of a pl011 gets deferred until after free_initmem(), an oops
ensues because pl011_console_match() is called which has been freed.
Fix by removing the __init attribute from the function and those it
calls.
Commit 10879ae5f12e ("serial: pl011: add console matching function")
introduced pl011_console_match() not just for early consoles but
regular preferred consoles, such as those added by acpi_parse_spcr().
Regular consoles may be registered after free_initmem() for various
reasons, one being deferred probing, another being dynamic enablement
of serial ports using a DeviceTree overlay.
Thus, pl011_console_match() must not be declared __init and the
functions it calls mustn't either.
Stack trace for posterity:
Unable to handle kernel paging request at virtual address 80c38b58
Internal error: Oops: 8000000d [#1] PREEMPT SMP ARM
PC is at pl011_console_match+0x0/0xfc
LR is at register_console+0x150/0x468
[<80187004>] (register_console)
[<805a8184>] (uart_add_one_port)
[<805b2b68>] (pl011_register_port)
[<805b3ce4>] (pl011_probe)
[<80569214>] (amba_probe)
[<805ca088>] (really_probe)
[<805ca2ec>] (driver_probe_device)
[<805ca5b0>] (__device_attach_driver)
[<805c8060>] (bus_for_each_drv)
[<805c9dfc>] (__device_attach)
[<805ca630>] (device_initial_probe)
[<805c90a8>] (bus_probe_device)
[<805c95a8>] (deferred_probe_work_func)
Fixes: 10879ae5f12e ("serial: pl011: add console matching function")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v4.10+
Cc: Aleksey Makarov <amakarov@marvell.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Christopher Covington <cov@codeaurora.org>
Link: https://lore.kernel.org/r/f827ff09da55b8c57d316a1b008a137677b58921.1597315557.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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pl011_probe() calls pl011_setup_port() to reserve an amba_ports[] entry,
then calls pl011_register_port() to register the uart driver with the
tty layer.
If registration of the uart driver fails, the amba_ports[] entry is not
released. If this happens 14 times (value of UART_NR macro), then all
amba_ports[] entries will have been leaked and driver probing is no
longer possible. (To be fair, that can only happen if the DeviceTree
doesn't contain alias IDs since they cause the same entry to be used for
a given port.) Fix it.
Fixes: ef2889f7ffee ("serial: pl011: Move uart_register_driver call to device")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org # v3.15+
Cc: Tushar Behera <tushar.behera@linaro.org>
Link: https://lore.kernel.org/r/138f8c15afb2f184d8102583f8301575566064a6.1597316167.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The following in 8250_exar.c line 589 is used to determine the number
of ports for each Exar board:
nr_ports = board->num_ports ? board->num_ports : pcidev->device & 0x0f;
If the number of ports a card has is not explicitly specified, it defaults
to the rightmost 4 bits of the PCI device ID. This is prone to error since
not all PCI device IDs contain a number which corresponds to the number of
ports that card provides.
This particular case involves COMMTECH_4222PCIE, COMMTECH_4224PCIE and
COMMTECH_4228PCIE cards with device IDs 0x0022, 0x0020 and 0x0021.
Currently the multiport cards receive 2, 0 and 1 port instead of 2, 4 and
8 ports respectively.
To fix this, each Commtech Fastcom PCIe card is given a struct where the
number of ports is explicitly specified. This ensures 'board->num_ports'
is used instead of the default 'pcidev->device & 0x0f'.
Fixes: d0aeaa83f0b0 ("serial: exar: split out the exar code from 8250_pci")
Signed-off-by: Valmer Huhn <valmer.huhn@concurrent-rt.com>
Tested-by: Valmer Huhn <valmer.huhn@concurrent-rt.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200813165255.GC345440@icarus.concurrent-rt.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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When booting with heavily modularized config, the serial console
may not be able to load until after init when modules that
satisfy needed dependencies have time to load.
Unfortunately, as qcom_geni_console_setup is marked as __init,
the function may have been freed before we get to run it,
causing boot time crashes such as:
[ 6.469057] Unable to handle kernel paging request at virtual address ffffffe645d4e6cc
[ 6.481623] Mem abort info:
[ 6.484466] ESR = 0x86000007
[ 6.487557] EC = 0x21: IABT (current EL), IL = 32 bits
[ 6.492929] SET = 0, FnV = 0g
[ 6.496016] EA = 0, S1PTW = 0
[ 6.499202] swapper pgtable: 4k pages, 39-bit VAs, pgdp=000000008151e000
[ 6.501286] ufshcd-qcom 1d84000.ufshc: ufshcd_print_pwr_info:[RX, TX]: gear=[3, 3], lane[2, 2], pwr[FAST MODE, FAST MODE], rate = 2
[ 6.505977] [ffffffe645d4e6cc] pgd=000000017df9f003, p4d=000000017df9f003, pud=000000017df9f003, pmd=000000017df9c003, pte=0000000000000000
[ 6.505990] Internal error: Oops: 86000007 [#1] PREEMPT SMP
[ 6.505995] Modules linked in: zl10353 zl10039 zl10036 zd1301_demod xc5000 xc4000 ves1x93 ves1820 tuner_xc2028 tuner_simple tuner_types tua9001 tua6100 1
[ 6.506152] isl6405
[ 6.518104] ufshcd-qcom 1d84000.ufshc: ufshcd_find_max_sup_active_icc_level: Regulator capability was not set, actvIccLevel=0
[ 6.530549] horus3a helene fc2580 fc0013 fc0012 fc0011 ec100 e4000 dvb_pll ds3000 drxk drxd drx39xyj dib9000 dib8000 dib7000p dib7000m dib3000mc dibx003
[ 6.624271] CPU: 7 PID: 148 Comm: kworker/7:2 Tainted: G W 5.8.0-mainline-12021-g6defd37ba1cd #3455
[ 6.624273] Hardware name: Thundercomm Dragonboard 845c (DT)
[ 6.624290] Workqueue: events deferred_probe_work_func
[ 6.624296] pstate: 40c00005 (nZcv daif +PAN +UAO BTYPE=--)
[ 6.624307] pc : qcom_geni_console_setup+0x0/0x110
[ 6.624316] lr : try_enable_new_console+0xa0/0x140
[ 6.624318] sp : ffffffc010843a30
[ 6.624320] x29: ffffffc010843a30 x28: ffffffe645c3e7d0
[ 6.624325] x27: ffffff80f8022180 x26: ffffffc010843b28
[ 6.637937] x25: 0000000000000000 x24: ffffffe6462a2000
[ 6.637941] x23: ffffffe646398000 x22: 0000000000000000
[ 6.637945] x21: 0000000000000000 x20: ffffffe6462a5ce8
[ 6.637952] x19: ffffffe646398e38 x18: ffffffffffffffff
[ 6.680296] x17: 0000000000000000 x16: ffffffe64492b900
[ 6.680300] x15: ffffffe6461e9d08 x14: 69202930203d2064
[ 6.680305] x13: 7561625f65736162 x12: 202c363331203d20
[ 6.696434] x11: 0000000000000030 x10: 0101010101010101
[ 6.696438] x9 : 4d4d20746120304d x8 : 7f7f7f7f7f7f7f7f
[ 6.707249] x7 : feff4c524c787373 x6 : 0000000000008080
[ 6.707253] x5 : 0000000000000000 x4 : 8080000000000000
[ 6.707257] x3 : 0000000000000000 x2 : ffffffe645d4e6cc
[ 6.744223] qcom_geni_serial 898000.serial: dev_pm_opp_set_rate: failed to find OPP for freq 102400000 (-34)
[ 6.744966] x1 : fffffffefe74e174 x0 : ffffffe6462a5ce8
[ 6.753580] qcom_geni_serial 898000.serial: dev_pm_opp_set_rate: failed to find OPP for freq 102400000 (-34)
[ 6.761634] Call trace:
[ 6.761639] qcom_geni_console_setup+0x0/0x110
[ 6.761645] register_console+0x29c/0x2f8
[ 6.767981] Bluetooth: hci0: Frame reassembly failed (-84)
[ 6.775252] uart_add_one_port+0x438/0x500
[ 6.775258] qcom_geni_serial_probe+0x2c4/0x4a8
[ 6.775266] platform_drv_probe+0x58/0xa8
[ 6.855359] really_probe+0xec/0x398
[ 6.855362] driver_probe_device+0x5c/0xb8
[ 6.855367] __device_attach_driver+0x98/0xb8
[ 7.184945] bus_for_each_drv+0x74/0xd8
[ 7.188825] __device_attach+0xec/0x148
[ 7.192705] device_initial_probe+0x24/0x30
[ 7.196937] bus_probe_device+0x9c/0xa8
[ 7.200816] deferred_probe_work_func+0x7c/0xb8
[ 7.205398] process_one_work+0x20c/0x4b0
[ 7.209456] worker_thread+0x48/0x460
[ 7.213157] kthread+0x14c/0x158
[ 7.216432] ret_from_fork+0x10/0x18
[ 7.220049] Code: bad PC value
[ 7.223139] ---[ end trace 73f3b21e251d5a70 ]---
Thus this patch removes the __init avoiding crash in such
configs.
Cc: Andy Gross <agross@kernel.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Todd Kjos <tkjos@google.com>
Cc: Amit Pundir <amit.pundir@linaro.org>
Cc: linux-arm-msm@vger.kernel.org
Cc: linux-serial@vger.kernel.org
Suggested-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20200811025044.70626-1-john.stultz@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The commit e42d6c3ec0c7 ("serial: qcom_geni_serial: Make kgdb work
even if UART isn't console") worked pretty well and I've been doing a
lot of debugging with it. However, recently I typed "dmesg" in kdb
and then held the space key down to scroll through the pagination. My
device hung. This was repeatable and I found that it was introduced
with the aforementioned commit.
It turns out that there are some strange boundary cases in geni where
in some weird situations it will signal RX_LAST but then will put 0 in
RX_LAST_BYTE. This means that the entire last FIFO entry is valid.
This weird corner case is handled in qcom_geni_serial_handle_rx()
where you can see that we only honor RX_LAST_BYTE if RX_LAST is set
_and_ RX_LAST_BYTE is non-zero. If either of these is not true we use
BYTES_PER_FIFO_WORD (4) for the size of the last FIFO word.
Let's fix kgdb. While at it, also use the proper #define for 4.
Fixes: e42d6c3ec0c7 ("serial: qcom_geni_serial: Make kgdb work even if UART isn't console")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Akash Asthana <akashast@codeaurora.org>
Link: https://lore.kernel.org/r/20200806221904.1.I4455ff86f0ef5281c2a0cd0a4712db614548a5ca@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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vc_resize() can return with an error after failure. Change VT_RESIZEX ioctl
to save struct vc_data values that are modified and restore the original
values in case of error.
Signed-off-by: George Kennedy <george.kennedy@oracle.com>
Cc: stable <stable@vger.kernel.org>
Reported-by: syzbot+38a3699c7eaf165b97a6@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/1596213192-6635-2-git-send-email-george.kennedy@oracle.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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syzbot is reporting UAF bug in set_origin() from vc_do_resize() [1], for
vc_do_resize() calls kfree(vc->vc_screenbuf) before calling set_origin().
Unfortunately, in set_origin(), vc->vc_sw->con_set_origin() might access
vc->vc_pos when scroll is involved in order to manipulate cursor, but
vc->vc_pos refers already released vc->vc_screenbuf until vc->vc_pos gets
updated based on the result of vc->vc_sw->con_set_origin().
Preserving old buffer and tolerating outdated vc members until set_origin()
completes would be easier than preventing vc->vc_sw->con_set_origin() from
accessing outdated vc members.
[1] https://syzkaller.appspot.com/bug?id=6649da2081e2ebdc65c0642c214b27fe91099db3
Reported-by: syzbot <syzbot+9116ecc1978ca3a12f43@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/1596034621-4714-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial updates from Greg KH:
"Here is the large set of TTY and Serial driver patches for 5.9-rc1.
Lots of bugfixes in here, thanks to syzbot fuzzing for serial and vt
and console code.
Other highlights include:
- much needed vt/vc code cleanup from Jiri Slaby
- 8250 driver fixes and additions
- various serial driver updates and feature enhancements
- locking cleanup for serial/console initializations
- other minor cleanups
All of these have been in linux-next with no reported issues"
* tag 'tty-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (90 commits)
MAINTAINERS: enlist Greg formally for console stuff
vgacon: Fix for missing check in scrollback handling
Revert "serial: 8250: Let serial core initialise spin lock"
serial: 8250: Let serial core initialise spin lock
tty: keyboard, do not speculate on func_table index
serial: stm32: Add RS485 RTS GPIO control
serial: 8250_dw: Fix common clocks usage race condition
serial: 8250_dw: Pass the same rate to the clk round and set rate methods
serial: 8250_dw: Simplify the ref clock rate setting procedure
serial: 8250: Add 8250 port clock update method
tty: serial: imx: add imx earlycon driver
tty: serial: imx: enable imx serial console port as module
tty/synclink: remove leftover bits of non-PCI card support
tty: Use the preferred form for passing the size of a structure type
tty: Fix identation issues in struct serial_struct32
tty: Avoid the use of one-element arrays
serial: msm_serial: add sparse context annotation
serial: pmac_zilog: add sparse context annotation
newport_con: vc_color is now in state
serial: imx: use hrtimers for rs485 delays
...
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull sched/fifo updates from Ingo Molnar:
"This adds the sched_set_fifo*() encapsulation APIs to remove static
priority level knowledge from non-scheduler code.
The three APIs for non-scheduler code to set SCHED_FIFO are:
- sched_set_fifo()
- sched_set_fifo_low()
- sched_set_normal()
These are two FIFO priority levels: default (high), and a 'low'
priority level, plus sched_set_normal() to set the policy back to
non-SCHED_FIFO.
Since the changes affect a lot of non-scheduler code, we kept this in
a separate tree"
* tag 'sched-fifo-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
sched,tracing: Convert to sched_set_fifo()
sched: Remove sched_set_*() return value
sched: Remove sched_setscheduler*() EXPORTs
sched,psi: Convert to sched_set_fifo_low()
sched,rcutorture: Convert to sched_set_fifo_low()
sched,rcuperf: Convert to sched_set_fifo_low()
sched,locktorture: Convert to sched_set_fifo()
sched,irq: Convert to sched_set_fifo()
sched,watchdog: Convert to sched_set_fifo()
sched,serial: Convert to sched_set_fifo()
sched,powerclamp: Convert to sched_set_fifo()
sched,ion: Convert to sched_set_normal()
sched,powercap: Convert to sched_set_fifo*()
sched,spi: Convert to sched_set_fifo*()
sched,mmc: Convert to sched_set_fifo*()
sched,ivtv: Convert to sched_set_fifo*()
sched,drm/scheduler: Convert to sched_set_fifo*()
sched,msm: Convert to sched_set_fifo*()
sched,psci: Convert to sched_set_fifo*()
sched,drbd: Convert to sched_set_fifo*()
...
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git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
- Herbert Xu made printk header file self-contained.
- Andy Shevchenko and Sergey Senozhatsky cleaned up console->setup()
error handling.
- Andy Shevchenko did some cleanups (e.g. sparse warning) in vsprintf
code.
- Minor documentation updates.
* tag 'printk-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
lib/vsprintf: Force type of flags value for gfp_t
lib/vsprintf: Replace custom spec to print decimals with generic one
lib/vsprintf: Replace hidden BUILD_BUG_ON() with static_assert()
printk: Make linux/printk.h self-contained
doc:kmsg: explicitly state the return value in case of SEEK_CUR
Replace HTTP links with HTTPS ones: vsprintf
hvc: unify console setup naming
console: Fix trivia typo 'change' -> 'chance'
console: Propagate error code from console ->setup()
tty: hvc: Return proper error code from console ->setup() hook
serial: sunzilog: Return proper error code from console ->setup() hook
serial: sunsab: Return proper error code from console ->setup() hook
mips: Return proper error code from console ->setup() hook
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git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull uninitialized_var() macro removal from Kees Cook:
"This is long overdue, and has hidden too many bugs over the years. The
series has several "by hand" fixes, and then a trivial treewide
replacement.
- Clean up non-trivial uses of uninitialized_var()
- Update documentation and checkpatch for uninitialized_var() removal
- Treewide removal of uninitialized_var()"
* tag 'uninit-macro-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
compiler: Remove uninitialized_var() macro
treewide: Remove uninitialized_var() usage
checkpatch: Remove awareness of uninitialized_var() macro
mm/debug_vm_pgtable: Remove uninitialized_var() usage
f2fs: Eliminate usage of uninitialized_var() macro
media: sur40: Remove uninitialized_var() usage
KVM: PPC: Book3S PR: Remove uninitialized_var() usage
clk: spear: Remove uninitialized_var() usage
clk: st: Remove uninitialized_var() usage
spi: davinci: Remove uninitialized_var() usage
ide: Remove uninitialized_var() usage
rtlwifi: rtl8192cu: Remove uninitialized_var() usage
b43: Remove uninitialized_var() usage
drbd: Remove uninitialized_var() usage
x86/mm/numa: Remove uninitialized_var() usage
docs: deprecated.rst: Add uninitialized_var()
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git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull tasklets API update from Kees Cook:
"These are the infrastructure updates needed to support converting the
tasklet API to something more modern (and hopefully for removal
further down the road).
There is a 300-patch series waiting in the wings to get set out to
subsystem maintainers, but these changes need to be present in the
kernel first. Since this has some treewide changes, I carried this
series for -next instead of paining Thomas with it in -tip, but it's
got his Ack.
This is similar to the timer_struct modernization from a while back,
but not nearly as messy (I hope). :)
- Prepare for tasklet API modernization (Romain Perier, Allen Pais,
Kees Cook)"
* tag 'tasklets-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
tasklet: Introduce new initialization API
treewide: Replace DECLARE_TASKLET() with DECLARE_TASKLET_OLD()
usb: gadget: udc: Avoid tasklet passing a global
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git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
Pull ARM SoC driver updates from Arnd Bergmann:
"A couple of subsystems have their own subsystem maintainers but choose
to have the code merged through the soc tree as upstream, as the code
tends to be used across multiple SoCs or has SoC specific drivers
itself:
- memory controllers:
Krzysztof Kozlowski takes ownership of the drivers/memory subsystem
and its drivers, starting out with a set of cleanup patches.
A larger driver for the Tegra memory controller that was
accidentally missed for v5.8 is now added.
- reset controllers:
Only minor updates to drivers/reset this time
- firmware:
The "turris mox" firmware driver gains support for signed firmware
blobs The tegra firmware driver gets extended to export some debug
information Various updates to i.MX firmware drivers, mostly
cosmetic
- ARM SCMI/SCPI:
A new mechanism for platform notifications is added, among a number
of minor changes.
- optee:
Probing of the TEE bus is rewritten to better support detection of
devices that depend on the tee-supplicant user space. A new
firmware based trusted platform module (fTPM) driver is added based
on OP-TEE
- SoC attributes:
A new driver is added to provide a generic soc_device for
identifying a machine through the SMCCC ARCH_SOC_ID firmware
interface rather than by probing SoC family specific registers.
The series also contains some cleanups to the common soc_device
code.
There are also a number of updates to SoC specific drivers, the main
ones are:
- Mediatek cmdq driver gains a few in-kernel interfaces
- Minor updates to Qualcomm RPMh, socinfo, rpm drivers, mostly adding
support for additional SoC variants
- The Qualcomm GENI core code gains interconnect path voting and
performance level support, and integrating this into a number of
device drivers.
- A new driver for Samsung Exynos5800 voltage coupler for
- Renesas RZ/G2H (R8A774E1) SoC support gets added to a couple of SoC
specific device drivers
- Updates to the TI K3 Ring Accelerator driver"
* tag 'arm-drivers-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (164 commits)
soc: qcom: geni: Fix unused label warning
soc: qcom: smd-rpm: Fix kerneldoc
memory: jz4780_nemc: Only request IO memory the driver will use
soc: qcom: pdr: Reorder the PD state indication ack
MAINTAINERS: Add Git repository for memory controller drivers
memory: brcmstb_dpfe: Fix language typo
memory: samsung: exynos5422-dmc: Correct white space issues
memory: samsung: exynos-srom: Correct alignment
memory: pl172: Enclose macro argument usage in parenthesis
memory: of: Correct kerneldoc
memory: omap-gpmc: Fix language typo
memory: omap-gpmc: Correct white space issues
memory: omap-gpmc: Use 'unsigned int' for consistency
memory: omap-gpmc: Enclose macro argument usage in parenthesis
memory: omap-gpmc: Correct kerneldoc
memory: mvebu-devbus: Align with open parenthesis
memory: mvebu-devbus: Add missing braces to all arms of if statement
memory: bt1-l2-ctl: Add blank lines after declarations
soc: TI knav_qmss: make symbol 'knav_acc_range_ops' static
firmware: ti_sci: Replace HTTP links with HTTPS ones
...
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Pull core block updates from Jens Axboe:
"Good amount of cleanups and tech debt removals in here, and as a
result, the diffstat shows a nice net reduction in code.
- Softirq completion cleanups (Christoph)
- Stop using ->queuedata (Christoph)
- Cleanup bd claiming (Christoph)
- Use check_events, moving away from the legacy media change
(Christoph)
- Use inode i_blkbits consistently (Christoph)
- Remove old unused writeback congestion bits (Christoph)
- Cleanup/unify submission path (Christoph)
- Use bio_uninit consistently, instead of bio_disassociate_blkg
(Christoph)
- sbitmap cleared bits handling (John)
- Request merging blktrace event addition (Jan)
- sysfs add/remove race fixes (Luis)
- blk-mq tag fixes/optimizations (Ming)
- Duplicate words in comments (Randy)
- Flush deferral cleanup (Yufen)
- IO context locking/retry fixes (John)
- struct_size() usage (Gustavo)
- blk-iocost fixes (Chengming)
- blk-cgroup IO stats fixes (Boris)
- Various little fixes"
* tag 'for-5.9/block-20200802' of git://git.kernel.dk/linux-block: (135 commits)
block: blk-timeout: delete duplicated word
block: blk-mq-sched: delete duplicated word
block: blk-mq: delete duplicated word
block: genhd: delete duplicated words
block: elevator: delete duplicated word and fix typos
block: bio: delete duplicated words
block: bfq-iosched: fix duplicated word
iocost_monitor: start from the oldest usage index
iocost: Fix check condition of iocg abs_vdebt
block: Remove callback typedefs for blk_mq_ops
block: Use non _rcu version of list functions for tag_set_list
blk-cgroup: show global disk stats in root cgroup io.stat
blk-cgroup: make iostat functions visible to stat printing
block: improve discard bio alignment in __blkdev_issue_discard()
block: change REQ_OP_ZONE_RESET and REQ_OP_ZONE_RESET_ALL to be odd numbers
block: defer flush request no matter whether we have elevator
block: make blk_timeout_init() static
block: remove retry loop in ioc_release_fn()
block: remove unnecessary ioc nested locking
block: integrate bd_start_claiming into __blkdev_get
...
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This reverts commit 679193b7baf8d88e41cbeb397ca17f797654947d.
It appears that in QEmu the lock has been initialised differently
(it wasn't obvious on real hardware during testing). Let's
revert the change until the better approach will be developed.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200802111612.36189-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Since the serial core handles spin lock initialisation,
let the driver rely on it.
Depends-on: f743061a85f5 ("serial: core: Initialise spin lock before use in uart_configure_port()")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200731123733.22754-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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It is very unlikely for processor to speculate on the func_table index.
The index is uchar and func_table is of size 256. So the compiler would
need to screw up and generate a really bad code.
But to stay on the safe side, forbid speculation on this user passed
index.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Jiri Kosina <jikos@kernel.org>
Link: https://lore.kernel.org/r/20200730105546.24268-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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This converts all the existing DECLARE_TASKLET() (and ...DISABLED)
macros with DECLARE_TASKLET_OLD() in preparation for refactoring the
tasklet callback type. All existing DECLARE_TASKLET() users had a "0"
data argument, it has been removed here as well.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
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While the STM32 does support RS485 drive-enable control within the
UART IP itself, some systems have the drive-enable line connected
to a pin which cannot be pinmuxed as RTS. Add support for toggling
the RTS GPIO line using the modem control GPIOs to provide at least
some sort of emulation.
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Manivannan Sadhasivam <mani@kernel.org>
Cc: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-stm32@st-md-mailman.stormreply.com
Link: https://lore.kernel.org/r/20200725144947.537007-1-marex@denx.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The race condition may happen if the UART reference clock is shared with
some other device (on Baikal-T1 SoC it's another DW UART port). In this
case if that device changes the clock rate while serial console is using
it the DW 8250 UART port might not only end up with an invalid uartclk
value saved, but may also experience a distorted output data since
baud-clock could have been changed. In order to fix this lets at least
try to adjust the 8250 port setting like UART clock rate in case if the
reference clock rate change is discovered. The driver will call the new
method to update 8250 UART port clock rate settings. It's done by means of
the clock event notifier registered at the port startup and unregistered
in the shutdown callback method.
Note 1. In order to avoid deadlocks we had to execute the UART port update
method in a dedicated deferred work. This is due to (in my opinion
redundant) the clock update implemented in the dw8250_set_termios()
method.
Note 2. Before the ref clock is manually changed by the custom
set_termios() function we swap the port uartclk value with new rate
adjusted to be suitable for the requested baud. It is necessary in
order to effectively disable a functionality of the ref clock events
handler for the current UART port, since uartclk update will be done
a bit further in the generic serial8250_do_set_termios() function.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200723003357.26897-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Indeed according to the clk API if clk_round_rate() has successfully
accepted a rate, then in order setup the clock with value returned by the
clk_round_rate() the clk_set_rate() method must be called with the
original rate value.
Suggested-by: Russell King <linux@armlinux.org.uk>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200723003357.26897-4-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Really instead of twice checking the clk_round_rate() return value
we could do it once, and if it isn't error the clock rate can be changed.
By doing so we decrease a number of ret-value tests and remove a weird
goto-based construction implemented in the dw8250_set_termios() method.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200723003357.26897-3-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Some platforms can be designed in a way so the UART port reference clock
might be asynchronously changed at some point. In Baikal-T1 SoC this may
happen due to the reference clock being shared between two UART ports, on
the Allwinner SoC the reference clock is derived from the CPU clock, so
any CPU frequency change should get to be known/reflected by/in the UART
controller as well. But it's not enough to just update the
uart_port->uartclk field of the corresponding UART port, the 8250
controller reference clock divisor should be altered so to preserve
current baud rate setting. All of these things is done in a coherent
way by calling the serial8250_update_uartclk() method provided in this
patch. Though note that it isn't supposed to be called from within the
UART port callbacks because the locks using to the protect the UART port
data are already taken in there.
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Link: https://lore.kernel.org/r/20200723003357.26897-2-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Split imx earlycon driver from imx serial driver "imx.c" as
separated driver. imx serial driver can be built as module,
but earlycon driver only support build in.
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Link: https://lore.kernel.org/r/20200724070815.11445-3-fugang.duan@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Add support for building i.MX serial driver as module.
The changes of the patch:
- imx console driver can be built as module.
- move out earlycon code to separated driver like imx_earlycon.c,
and imx earlycon driver only support build-in.
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Link: https://lore.kernel.org/r/20200724070815.11445-2-fugang.duan@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Since commit 1355cba9c3ba ("tty/synclink: remove ISA support"), the
synlink driver only supports PCI card. Remove any leftover dead code
to support other cards.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20200727130501.31005-1-hch@lst.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use the preferred form for passing the size of a structure type. The
alternative form where the structure type is spelled out hurts
readability and introduces an opportunity for a bug when the object
type is changed but the corresponding object identifier to which the
sizeof operator is applied is not.
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/b04dd8cdd67bd6ffde3fd12940aeef35fdb824a6.1595543280.git.gustavoars@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Fix the following checkpatch.pl warnings together with all the
identation issues in struct serial_struct32:
ERROR: code indent should use tabs where possible
+ char reserved_char;$
WARNING: please, no spaces at the start of a line
+ char reserved_char;$
ERROR: code indent should use tabs where possible
+ compat_int_t reserved;$
WARNING: please, no spaces at the start of a line
+ compat_int_t reserved;$
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/77576843397aeab0af8aa0423a9768f3ca8dedfb.1595543280.git.gustavoars@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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One-element arrays are being deprecated[1]. Replace the one-element arrays
with simple value types 'char reserved_char' and 'compat_int_t reserved'[2],
once it seems these are just placeholders for alignment.
[1] https://github.com/KSPP/linux/issues/79
[2] https://github.com/KSPP/linux/issues/86
Tested-by: kernel test robot <lkp@intel.com>
Link: https://github.com/GustavoARSilva/linux-hardening/blob/master/cii/0-day/tty-20200716.md
Acked-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/f49bf0e27eaac396c96d21392c8c284f9f5ef52a.1595543280.git.gustavoars@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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we need the tty/serial fixes in here as well.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Sealevel XR17V35X based devices are inoperable on kernel versions
4.11 and above due to a change in the GPIO preconfiguration introduced in
commit
7dea8165f1d. This patch fixes this by preconfiguring the GPIO on Sealevel
cards to the value (0x00) used prior to commit 7dea8165f1d
With GPIOs preconfigured as per commit 7dea8165f1d 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: 7dea8165f1d6 ("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>
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Add sparse context annotation to the receive handlers, which release and
reacquire the port lock, to silence sparse warnings:
drivers/tty/serial/msm_serial.c:748:25: warning: context imbalance in 'msm_handle_rx_dm' - unexpected unlock
drivers/tty/serial/msm_serial.c:814:28: warning: context imbalance in 'msm_handle_rx' - unexpected unlock
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200723123327.5843-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Add sparse context annotation to the receive handler, which releases and
reacquires the port lock, to silence a sparse warning:
drivers/tty/serial/pmac_zilog.c:255:36: sparse: sparse: context imbalance in 'pmz_receive_chars' - unexpected unlock
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200723123327.5843-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Commit 7b668c064ec3 ("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 7b668c064ec3 ("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-dani |