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2022-09-28serial: tegra-tcu: Use uart_xmit_advance(), fixes icount.tx accountingIlpo Järvinen1-1/+1
commit 1d10cd4da593bc0196a239dcc54dac24b6b0a74e upstream. Tx'ing does not correctly account Tx'ed characters into icount.tx. Using uart_xmit_advance() fixes the problem. Fixes: 2d908b38d409 ("serial: Add Tegra Combined UART driver") Cc: <stable@vger.kernel.org> # serial: Create uart_xmit_advance() Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220901143934.8850-4-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-28serial: tegra: Use uart_xmit_advance(), fixes icount.tx accountingIlpo Järvinen1-3/+2
commit 754f68044c7dd6c52534ba3e0f664830285c4b15 upstream. DMA complete & stop paths did not correctly account Tx'ed characters into icount.tx. Using uart_xmit_advance() fixes the problem. Fixes: e9ea096dd225 ("serial: tegra: add serial driver") Cc: <stable@vger.kernel.org> # serial: Create uart_xmit_advance() Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220901143934.8850-3-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-28tty: serial: atmel: Preserve previous USART mode if RS485 disabledSergiu Moga1-3/+1
[ Upstream commit 692a8ebcfc24f4a5bea0eb2967e450f584193da6 ] Whenever the atmel_rs485_config() driver method would be called, the USART mode is reset to normal mode before even checking if RS485 flag is set, thus resulting in losing the previous USART mode in the case where the checking fails. Some tools, such as `linux-serial-test`, lead to the driver calling this method when doing the setup of the serial port: after setting the port mode (Hardware Flow Control, Normal Mode, RS485 Mode, etc.), `linux-serial-test` tries to enable/disable RS485 depending on the commandline arguments that were passed. Example of how this issue could reveal itself: When doing a serial communication with Hardware Flow Control through `linux-serial-test`, the tool would lead to the driver roughly doing the following: - set the corresponding bit to 1 (ATMEL_US_USMODE_HWHS bit in the ATMEL_US_MR register) through the atmel_set_termios() to enable Hardware Flow Control - disable RS485 through the atmel_config_rs485() method Thus, when the latter is called, the mode will be reset and the previously set bit is unset, leaving USART in normal mode instead of the expected Hardware Flow Control mode. This fix ensures that this reset is only done if the checking for RS485 succeeds and that the previous mode is preserved otherwise. Fixes: e8faff7330a35 ("ARM: 6092/1: atmel_serial: support for RS485 communications") Cc: stable <stable@kernel.org> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com> Link: https://lore.kernel.org/r/20220824142902.502596-1-sergiu.moga@microchip.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28serial: atmel: remove redundant assignment in rs485_configLino Sanfilippo1-3/+1
[ Upstream commit 60efd0513916f195dd85bfbf21653f74f9ab019c ] In uart_set_rs485_config() the serial core already assigns the passed serial_rs485 struct to the uart port. So remove the assignment from the drivers rs485_config() function to avoid redundancy. Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com> Acked-by: Richard Genoud <richard.genoud@gmail.com> Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Link: https://lore.kernel.org/r/20220410104642.32195-10-LinoSanfilippo@gmx.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Stable-dep-of: 692a8ebcfc24 ("tty: serial: atmel: Preserve previous USART mode if RS485 disabled") Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-23Revert "serial: 8250: Fix reporting real baudrate value in c_ospeed field"Johan Hovold1-17/+0
commit d02b006b29de14968ba4afa998bede0d55469e29 upstream. This reverts commit 32262e2e429cdb31f9e957e997d53458762931b7. The commit in question claims to determine the inverse of serial8250_get_divisor() but failed to notice that some drivers override the default implementation using a get_divisor() callback. This means that the computed line-speed values can be completely wrong and results in regular TCSETS requests failing (the incorrect values would also be passed to any overridden set_divisor() callback). Similarly, it also failed to honour the old (deprecated) ASYNC_SPD_FLAGS and would break applications relying on those when re-encoding the actual line speed. There are also at least two quirks, UART_BUG_QUOT and an OMAP1510 workaround, which were happily ignored and that are now broken. Finally, even if the offending commit were to be implemented correctly, this is a new feature and not something which should be backported to stable. Cc: Pali Rohár <pali@kernel.org> Fixes: 32262e2e429c ("serial: 8250: Fix reporting real baudrate value in c_ospeed field") Cc: stable <stable@vger.kernel.org> Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20211007133146.28949-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-23serial: 8250: Fix reporting real baudrate value in c_ospeed fieldPali Rohár1-0/+17
[ Upstream commit 32262e2e429cdb31f9e957e997d53458762931b7 ] In most cases it is not possible to set exact baudrate value to hardware. So fix reporting real baudrate value which was set to hardware via c_ospeed termios field. It can be retrieved by ioctl(TCGETS2) from userspace. Real baudrate value is calculated from chosen hardware divisor and base clock. It is implemented in a new function serial8250_compute_baud_rate() which is inverse of serial8250_get_divisor() function. With this change is fixed also UART timeout value (it is updated via uart_update_timeout() function), which is calculated from the now fixed baudrate value too. Cc: stable@vger.kernel.org Signed-off-by: Pali Rohár <pali@kernel.org> Link: https://lore.kernel.org/r/20210927093704.19768-1-pali@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15tty: n_gsm: avoid call of sleeping functions from atomic contextFedor Pchelkin1-21/+18
commit 902e02ea9385373ce4b142576eef41c642703955 upstream. Syzkaller reports the following problem: BUG: sleeping function called from invalid context at kernel/printk/printk.c:2347 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1105, name: syz-executor423 3 locks held by syz-executor423/1105: #0: ffff8881468b9098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x90 drivers/tty/tty_ldisc.c:266 #1: ffff8881468b9130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: tty_write_lock drivers/tty/tty_io.c:952 [inline] #1: ffff8881468b9130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: do_tty_write drivers/tty/tty_io.c:975 [inline] #1: ffff8881468b9130 (&tty->atomic_write_lock){+.+.}-{3:3}, at: file_tty_write.constprop.0+0x2a8/0x8e0 drivers/tty/tty_io.c:1118 #2: ffff88801b06c398 (&gsm->tx_lock){....}-{2:2}, at: gsmld_write+0x5e/0x150 drivers/tty/n_gsm.c:2717 irq event stamp: 3482 hardirqs last enabled at (3481): [<ffffffff81d13343>] __get_reqs_available+0x143/0x2f0 fs/aio.c:946 hardirqs last disabled at (3482): [<ffffffff87d39722>] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (3482): [<ffffffff87d39722>] _raw_spin_lock_irqsave+0x52/0x60 kernel/locking/spinlock.c:159 softirqs last enabled at (3408): [<ffffffff87e01002>] asm_call_irq_on_stack+0x12/0x20 softirqs last disabled at (3401): [<ffffffff87e01002>] asm_call_irq_on_stack+0x12/0x20 Preemption disabled at: [<0000000000000000>] 0x0 CPU: 2 PID: 1105 Comm: syz-executor423 Not tainted 5.10.137-syzkaller #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x107/0x167 lib/dump_stack.c:118 ___might_sleep.cold+0x1e8/0x22e kernel/sched/core.c:7304 console_lock+0x19/0x80 kernel/printk/printk.c:2347 do_con_write+0x113/0x1de0 drivers/tty/vt/vt.c:2909 con_write+0x22/0xc0 drivers/tty/vt/vt.c:3296 gsmld_write+0xd0/0x150 drivers/tty/n_gsm.c:2720 do_tty_write drivers/tty/tty_io.c:1028 [inline] file_tty_write.constprop.0+0x502/0x8e0 drivers/tty/tty_io.c:1118 call_write_iter include/linux/fs.h:1903 [inline] aio_write+0x355/0x7b0 fs/aio.c:1580 __io_submit_one fs/aio.c:1952 [inline] io_submit_one+0xf45/0x1a90 fs/aio.c:1999 __do_sys_io_submit fs/aio.c:2058 [inline] __se_sys_io_submit fs/aio.c:2028 [inline] __x64_sys_io_submit+0x18c/0x2f0 fs/aio.c:2028 do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xc6 The problem happens in the following control flow: gsmld_write(...) spin_lock_irqsave(&gsm->tx_lock, flags) // taken a spinlock on TX data con_write(...) do_con_write(...) console_lock() might_sleep() // -> bug As far as console_lock() might sleep it should not be called with spinlock held. The patch replaces tx_lock spinlock with mutex in order to avoid the problem. Found by Linux Verification Center (linuxtesting.org) with Syzkaller. Fixes: 32dd59f ("tty: n_gsm: fix race condition in gsmld_write()") Cc: stable <stable@kernel.org> Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Link: https://lore.kernel.org/r/20220829131640.69254-3-pchelkin@ispras.ru Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-15tty: n_gsm: initialize more members at gsm_alloc_mux()Tetsuo Handa1-5/+4
commit 4bb1a53be85fcb1e24c14860e326a00cdd362c28 upstream. syzbot is reporting use of uninitialized spinlock at gsmld_write() [1], for commit 32dd59f ("tty: n_gsm: fix race condition in gsmld_write()") allows accessing gsm->tx_lock before gsm_activate_mux() initializes it. Since object initialization should be done right after allocation in order to avoid accessing uninitialized memory, move initialization of timer/work/waitqueue/spinlock from gsmld_open()/gsm_activate_mux() to gsm_alloc_mux(). Link: https://syzkaller.appspot.com/bug?extid=cf155def4e717db68a12 [1] Fixes: 32dd59f ("tty: n_gsm: fix race condition in gsmld_write()") Reported-by: syzbot <syzbot+cf155def4e717db68a12@syzkaller.appspotmail.com> Tested-by: syzbot <syzbot+cf155def4e717db68a12@syzkaller.appspotmail.com> Cc: stable <stable@kernel.org> Acked-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Link: https://lore.kernel.org/r/2110618e-57f0-c1ce-b2ad-b6cacef3f60e@I-love.SAKURA.ne.jp Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-08tty: serial: lpuart: disable flow control while waiting for the transmit ↵Sherry Sun1-0/+1
engine to complete commit d5a2e0834364377a5d5a2fff1890a0b3f0bafd1f upstream. When the user initializes the uart port, and waits for the transmit engine to complete in lpuart32_set_termios(), if the UART TX fifo has dirty data and the UARTMODIR enable the flow control, the TX fifo may never be empty. So here we should disable the flow control first to make sure the transmit engin can complete. Fixes: 380c966c093e ("tty: serial: fsl_lpuart: add 32-bit register interface support") Cc: stable <stable@kernel.org> Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Link: https://lore.kernel.org/r/20220821101527.10066-1-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-08vt: Clear selection before changing the fontHelge Deller1-4/+8
commit 566f9c9f89337792070b5a6062dff448b3e7977f upstream. When changing the console font with ioctl(KDFONTOP) the new font size can be bigger than the previous font. A previous selection may thus now be outside of the new screen size and thus trigger out-of-bounds accesses to graphics memory if the selection is removed in vc_do_resize(). Prevent such out-of-memory accesses by dropping the selection before the various con_font_set() console handlers are called. Reported-by: syzbot+14b0e8f3fd1612e35350@syzkaller.appspotmail.com Cc: stable <stable@kernel.org> Tested-by: Khalid Masum <khalid.masum.92@gmail.com> Signed-off-by: Helge Deller <deller@gmx.de> Link: https://lore.kernel.org/r/YuV9apZGNmGfjcor@p100 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-09-08serial: fsl_lpuart: RS485 RTS polariy is inverseShenwei Wang1-2/+2
commit 846651eca073e2e02e37490a4a52752415d84781 upstream. The setting of RS485 RTS polarity is inverse in the current driver. When the property of 'rs485-rts-active-low' is enabled in the dts node, the RTS signal should be LOW during sending. Otherwise, if there is no such a property, the RTS should be HIGH during sending. Fixes: 03895cf41d18 ("tty: serial: fsl_lpuart: Add support for RS-485") Cc: stable <stable@kernel.org> Signed-off-by: Nicolas Diaz <nicolas.diaz@nxp.com> Signed-off-by: Shenwei Wang <shenwei.wang@nxp.com> Link: https://lore.kernel.org/r/20220805144529.604856-1-shenwei.wang@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25tty: serial: Fix refcount leak bug in ucc_uart.cLiang He1-0/+2
[ Upstream commit d24d7bb2cd947676f9b71fb944d045e09b8b282f ] In soc_info(), of_find_node_by_type() will return a node pointer with refcount incremented. We should use of_node_put() when it is not used anymore. Acked-by: Timur Tabi <timur@kernel.org> Signed-off-by: Liang He <windhl@126.com> Link: https://lore.kernel.org/r/20220618060850.4058525-1-windhl@126.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21serial: 8250: Fold EndRun device support into OxSemi Tornado codeMaciej W. Rozycki1-51/+25
[ Upstream commit 1f32c65bad24b9787d3e52843de375430e3df822 ] The EndRun PTP/1588 dual serial port device is based on the Oxford Semiconductor OXPCIe952 UART device with the PCI vendor:device ID set for EndRun Technologies and uses the same sequence to determine the number of ports available. Despite that we have duplicate code specific to the EndRun device. Remove redundant code then and factor out OxSemi Tornado device detection. Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181516220.9383@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21serial: 8250_pci: Replace dev_*() by pci_*() macrosAndy Shevchenko1-30/+22
[ Upstream commit 1177384179416c7136e1348f07609e0da1ae6b91 ] PCI subsystem provides convenient shortcut macros for message printing. Use those macros instead of dev_*(). Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Jiri Slaby <jslaby@kernel.org> Link: https://lore.kernel.org/r/20211022135147.70965-3-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21serial: 8250_pci: Refactor the loop in pci_ite887x_init()Andy Shevchenko1-8/+4
[ Upstream commit 35b4f17231923e2f64521bdf7a2793ce2c3c74a6 ] The loop can be refactored by using ARRAY_SIZE() instead of NULL terminator. This reduces code base and makes it easier to read and understand. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Jiri Slaby <jslaby@kernel.org> Link: https://lore.kernel.org/r/20211022135147.70965-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21serial: 8250: Correct the clock for OxSemi PCIe devicesMaciej W. Rozycki1-64/+64
[ Upstream commit 6cbe45d8ac9316ceedd0749759bd54caf03f7012 ] Oxford Semiconductor PCIe (Tornado) serial port devices are driven by a fixed 62.5MHz clock input derived from the 100MHz PCI Express clock. In the enhanced (650) mode, which we select in `autoconfig_has_efr' by setting the ECB bit in the EFR register, and in the absence of clock reconfiguration, which we currently don't do, the clock rate is divided only by the oversampling rate of 16 as it is supplied to the baud rate generator, yielding the baud base of 3906250. This comes from the reset values of the TCR and MCR[7] registers which are both zero[1][2][3][4], choosing the oversampling rate of 16 and the normal (divide by 1) baud rate generator prescaler respectively. This is the rate that is divided by the value held in the divisor latch to determine the baud rate used. Replace the incorrect baud base of 4000000 with the right value of 3906250 then. References: [1] "OXPCIe200 PCI Express Multi-Port Bridge", Oxford Semiconductor, Inc., DS-0045, 10 Nov 2008, Section "Reset Configuration", p. 72 [2] "OXPCIe952 PCI Express Bridge to Dual Serial & Parallel Port", Oxford Semiconductor, Inc., DS-0046, Mar 06 08, Section "Reset Configuration", p. 27 [3] "OXPCIe954 PCI Express Bridge to Quad Serial Port", Oxford Semiconductor, Inc., DS-0047, Feb 08, Section "Reset Configuration", p. 28 [4] "OXPCIe958 PCI Express Bridge to Octal Serial Port", Oxford Semiconductor, Inc., DS-0048, Feb 08, Section "Reset Configuration", p. 28 Fixes: 7106b4e333bae ("8250: Oxford Semiconductor Devices") Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106100203510.5469@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21serial: 8250: Dissociate 4MHz Titan ports from Oxford portsMaciej W. Rozycki1-6/+38
[ Upstream commit f771a34b141124a68265f91acae34cdb08aeb9e0 ] Oxford Semiconductor PCIe (Tornado) serial port devices have their baud base set incorrectly, however their `pciserial_board' entries have been reused for Titan serial port devices. Define own entries for the latter devices then, carrying over the settings, so that Oxford entries can be fixed. Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2106100142310.5469@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21tty: n_gsm: fix missing corner cases in gsmld_poll()Daniel Starke1-2/+5
[ Upstream commit 7e5b4322cde067e1d0f1bf8f490e93f664a7c843 ] gsmld_poll() currently fails to handle the following corner cases correctly: - remote party closed the associated tty Add the missing checks and map those to EPOLLHUP. Reorder the checks to group them by their reaction. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Daniel Starke <daniel.starke@siemens.com> Link: https://lore.kernel.org/r/20220707113223.3685-4-daniel.starke@siemens.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21tty: n_gsm: fix DM commandDaniel Starke1-1/+1
[ Upstream commit 18a948c7d90995d127785e308fa7b701df4c499f ] n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010. See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516 The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to the newer 27.010 here. Chapter 5.3.3 defines the DM response. There exists no DM command. However, the current implementation incorrectly sends DM as command in case of unexpected UIH frames in gsm_queue(). Correct this behavior by always sending DM as response. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Daniel Starke <daniel.starke@siemens.com> Link: https://lore.kernel.org/r/20220707113223.3685-2-daniel.starke@siemens.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21tty: n_gsm: fix wrong T1 retry count handlingDaniel Starke1-2/+2
[ Upstream commit f30e10caa80aa1f35508bc17fc302dbbde9a833c ] n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010. See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516 The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to the newer 27.010 here. Chapter 5.7.3 states that the valid range for the maximum number of retransmissions (N2) is from 0 to 255 (both including). gsm_dlci_t1() handles this number incorrectly by performing N2 - 1 retransmission attempts. Setting N2 to zero results in more than 255 retransmission attempts. Fix gsm_dlci_t1() to comply with 3GPP 27.010. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Daniel Starke <daniel.starke@siemens.com> Link: https://lore.kernel.org/r/20220707113223.3685-1-daniel.starke@siemens.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21tty: n_gsm: fix race condition in gsmld_write()Daniel Starke1-4/+17
[ Upstream commit 32dd59f96924f45e33bc79854f7a00679c0fa28e ] The function may be used by the user directly and also by the n_gsm internal functions. They can lead into a race condition which results in interleaved frames if both are writing at the same time. The receiving side is not able to decode those interleaved frames correctly. Add a lock around the low side tty write to avoid race conditions and frame interleaving between user originated writes and n_gsm writes. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Daniel Starke <daniel.starke@siemens.com> Link: https://lore.kernel.org/r/20220701061652.39604-9-daniel.starke@siemens.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21tty: n_gsm: fix packet re-transmission without open control channelDaniel Starke1-1/+1
[ Upstream commit 4fae831b3a71fc5a44cc5c7d0b8c1267ee7659f5 ] In the current implementation control packets are re-transmitted even if the control channel closed down during T2. This is wrong. Check whether the control channel is open before re-transmitting any packets. Note that control channel open/close is handled by T1 and not T2 and remains unaffected by this. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Daniel Starke <daniel.starke@siemens.com> Link: https://lore.kernel.org/r/20220701061652.39604-7-daniel.starke@siemens.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21tty: n_gsm: fix non flow control frames during mux flow offDaniel Starke1-1/+53
[ Upstream commit bec0224816d19abe4fe503586d16d51890540615 ] n_gsm is based on the 3GPP 07.010 and its newer version is the 3GPP 27.010. See https://portal.3gpp.org/desktopmodules/Specifications/SpecificationDetails.aspx?specificationId=1516 The changes from 07.010 to 27.010 are non-functional. Therefore, I refer to the newer 27.010 here. Chapter 5.4.6.3.6 states that FCoff stops the transmission on all channels except the control channel. This is already implemented in gsm_data_kick(). However, chapter 5.4.8.1 explains that this shall result in the same behavior as software flow control on the ldisc in advanced option mode. That means only flow control frames shall be sent during flow off. The current implementation does not consider this case. Change gsm_data_kick() to send only flow control frames if constipated to abide the standard. gsm_read_ea_val() and gsm_is_flow_ctrl_msg() are introduced as helper functions for this. It is planned to use gsm_read_ea_val() in later code cleanups for other functions, too. Fixes: c01af4fec2c8 ("n_gsm : Flow control handling in Mux driver") Signed-off-by: Daniel Starke <daniel.starke@siemens.com> Link: https://lore.kernel.org/r/20220701061652.39604-5-daniel.starke@siemens.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21tty: n_gsm: fix wrong queuing behavior in gsm_dlci_data_output()Daniel Starke1-32/+42
[ Upstream commit 556fc8ac06513cced381588d6d58c184d95cc4fe ] 1) The function drains the fifo for the given user tty/DLCI without considering 'TX_THRESH_HI' and different to gsm_dlci_data_output_framed(), which moves only one packet from the user side to the internal transmission queue. We can only handle one packet at a time here if we want to allow DLCI priority handling in gsm_dlci_data_sweep() to avoid link starvation. 2) Furthermore, the additional header octet from convergence layer type 2 is not counted against MTU. It is part of the UI/UIH frame message which needs to be limited to MTU. Hence, it is wrong not to consider this octet. 3) Finally, the waiting user tty is not informed about freed space in its send queue. Take at most one packet worth of data out of the DLCI fifo to fix 1). Limit the max user data size per packet to MTU - 1 in case of convergence layer type 2 to leave space for the control signal octet which is added in the later part of the function. This fixes 2). Add tty_port_tty_wakeup() to wake up the user tty if new write space has been made available to fix 3). Fixes: 268e526b935e ("tty/n_gsm: avoid fifo overflow in gsm_dlci_data_output") Signed-off-by: Daniel Starke <daniel.starke@siemens.com> Link: https://lore.kernel.org/r/20220701061652.39604-3-daniel.starke@siemens.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21tty: n_gsm: fix user open not possible at responder until initiator openDaniel Starke1-2/+29
[ Upstream commit ac77f0077c3265197d378158c85a55eee6d21508 ] After setting up the control channel on both sides the responder side may want to open a virtual tty to listen on until the initiator starts an application on a user channel. The current implementation allows the open() but no other operation, like termios. These fail with EINVAL. The responder sided application has no means to detect an open by the initiator sided application this way. And the initiator sided applications usually expect the responder sided application to listen on the user channel upon open. Set the user channel into half-open state on responder side once a user application opens the virtual tty to allow IO operations on it. Furthermore, keep the user channel constipated until the initiator side opens it to give the responder sided application the chance to detect the new connection and to avoid data loss if the responder sided application starts sending before the user channel is open. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Signed-off-by: Daniel Starke <daniel.starke@siemens.com> Link: https://lore.kernel.org/r/20220701061652.39604-1-daniel.starke@siemens.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21tty: n_gsm: Delete gsmtty open SABM frame when config requesterZhenguo Zhao1-1/+3
[ Upstream commit cbff2b32516881bef30bbebf413d1b49495bab1d ] When n_gsm config "initiator=0",as requester ,it doesn't need to send SABM frame data during gsmtty open. Example,when gsmtty open,it will send SABM frame.for initiator,it maybe not want to receive the frame. [ 88.410426] c1 gsmld_output: 00000000: f9 07 3f 01 de f9 [ 88.420839] c1 --> 1) R: SABM(F) Signed-off-by: Zhenguo Zhao <Zhenguo.Zhao1@unisoc.com> Link: https://lore.kernel.org/r/1629461872-26965-6-git-send-email-zhenguo6858@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21serial: 8250_dw: Store LSR into lsr_saved_flags in dw8250_tx_wait_empty()Ilpo Järvinen1-0/+3
[ Upstream commit af14f3007e2dca0d112f10f6717ba43093f74e81 ] Make sure LSR flags are preserved in dw8250_tx_wait_empty(). This function is called from a low-level out function and therefore cannot call serial_lsr_in() as it would lead to infinite recursion. It is borderline if the flags need to be saved here at all since this code relates to writing LCR register which usually implies no important characters should be arriving. Fixes: 914eaf935ec7 ("serial: 8250_dw: Allow TX FIFO to drain before writing to UART_LCR") Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220608095431.18376-7-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21serial: 8250: Export ICR access helpers for internal useMaciej W. Rozycki2-21/+22
[ Upstream commit cb5a40e3143bc64437858b337273fd63cc42e9c2 ] Make ICR access helpers available outside 8250_port.c, however retain them as ordinary static functions so as not to regress code generation. This is because `serial_icr_write' is currently automatically inlined by GCC, however `serial_icr_read' is not. Making them both static inline would grow code produced, e.g.: $ i386-linux-gnu-size --format=gnu 8250_port-{old,new}.o text data bss total filename 15065 3378 0 18443 8250_port-old.o 15289 3378 0 18667 8250_port-new.o and: $ riscv64-linux-gnu-size --format=gnu 8250_port-{old,new}.o text data bss total filename 16980 5306 0 22286 8250_port-old.o 17124 5306 0 22430 8250_port-new.o while making them external would needlessly add a new module interface and lose the benefit from `serial_icr_write' getting inlined outside 8250_port.o. Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181517500.9383@angie.orcam.me.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-21serial: mvebu-uart: uart2 error bits clearingNarendra Hadke1-0/+11
commit a7209541239e5dd44d981289e5f9059222d40fd1 upstream. For mvebu uart2, error bits are not cleared on buffer read. This causes interrupt loop and system hang. Cc: stable@vger.kernel.org Reviewed-by: Yi Guo <yi.guo@cavium.com> Reviewed-by: Nadav Haklai <nadavh@marvell.com> Signed-off-by: Narendra Hadke <nhadke@marvell.com> Signed-off-by: Pali Rohár <pali@kernel.org> Link: https://lore.kernel.org/r/20220726091221.12358-1-pali@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-21tty: vt: initialize unicode screen bufferTetsuo Handa1-1/+1
commit af77c56aa35325daa2bc2bed5c2ebf169be61b86 upstream. syzbot reports kernel infoleak at vcs_read() [1], for buffer can be read immediately after resize operation. Initialize buffer using kzalloc(). ---------- #include <fcntl.h> #include <unistd.h> #include <sys/ioctl.h> #include <linux/fb.h> int main(int argc, char *argv[]) { struct fb_var_screeninfo var = { }; const int fb_fd = open("/dev/fb0", 3); ioctl(fb_fd, FBIOGET_VSCREENINFO, &var); var.yres = 0x21; ioctl(fb_fd, FBIOPUT_VSCREENINFO, &var); return read(open("/dev/vcsu", O_RDONLY), &var, sizeof(var)) == -1; } ---------- Link: https://syzkaller.appspot.com/bug?extid=31a641689d43387f05d3 [1] Cc: stable <stable@vger.kernel.org> Reported-by: syzbot <syzbot+31a641689d43387f05d3@syzkaller.appspotmail.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Link: https://lore.kernel.org/r/4ef053cf-e796-fb5e-58b7-3ae58242a4ad@I-love.SAKURA.ne.jp Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29tty: use new tty_insert_flip_string_and_push_buffer() in pty_write()Jiri Slaby2-12/+33
commit a501ab75e7624d133a5a3c7ec010687c8b961d23 upstream. There is a race in pty_write(). pty_write() can be called in parallel with e.g. ioctl(TIOCSTI) or ioctl(TCXONC) which also inserts chars to the buffer. Provided, tty_flip_buffer_push() in pty_write() is called outside the lock, it can commit inconsistent tail. This can lead to out of bounds writes and other issues. See the Link below. To fix this, we have to introduce a new helper called tty_insert_flip_string_and_push_buffer(). It does both tty_insert_flip_string() and tty_flip_buffer_commit() under the port lock. It also calls queue_work(), but outside the lock. See 71a174b39f10 (pty: do tty_flip_buffer_push without port->lock in pty_write) for the reasons. Keep the helper internal-only (in drivers' tty.h). It is not intended to be used widely. Link: https://seclists.org/oss-sec/2022/q2/155 Fixes: 71a174b39f10 (pty: do tty_flip_buffer_push without port->lock in pty_write) Cc: 一只狗 <chennbnbnb@gmail.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Suggested-by: Hillf Danton <hdanton@sina.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20220707082558.9250-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29tty: extract tty_flip_buffer_commit() from tty_flip_buffer_push()Jiri Slaby1-5/+10
commit 716b10580283fda66f2b88140e3964f8a7f9da89 upstream. We will need this new helper in the next patch. Cc: Hillf Danton <hdanton@sina.com> Cc: 一只狗 <chennbnbnb@gmail.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20220707082558.9250-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29tty: drop tty_schedule_flip()Jiri Slaby1-22/+8
commit 5db96ef23bda6c2a61a51693c85b78b52d03f654 upstream. Since commit a9c3f68f3cd8d (tty: Fix low_latency BUG) in 2014, tty_flip_buffer_push() is only a wrapper to tty_schedule_flip(). All users were converted in the previous patches, so remove tty_schedule_flip() completely while inlining its body into tty_flip_buffer_push(). One less exported function. Reviewed-by: Johan Hovold <johan@kernel.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211122111648.30379-4-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29tty: drivers/tty/, stop using tty_schedule_flip()Jiri Slaby6-11/+11
commit 5f6a85158ccacc3f09744b3aafe8b11ab3b6c6f6 upstream. Since commit a9c3f68f3cd8d (tty: Fix low_latency BUG) in 2014, tty_flip_buffer_push() is only a wrapper to tty_schedule_flip(). We are going to remove the latter (as it is used less), so call the former in drivers/tty/. Cc: Vladimir Zapolskiy <vz@mleia.com> Reviewed-by: Johan Hovold <johan@kernel.org> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20211122111648.30379-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-29serial: mvebu-uart: correctly report configured baudrate valuePali Rohár1-12/+13
commit 4f532c1e25319e42996ec18a1f473fd50c8e575d upstream. Functions tty_termios_encode_baud_rate() and uart_update_timeout() should be called with the baudrate value which was set to hardware. Linux then report exact values via ioctl(TCGETS2) to userspace. Change mvebu_uart_baud_rate_set() function to return baudrate value which was set to hardware and propagate this value to above mentioned functions. With this change userspace would see precise value in termios c_ospeed field. Fixes: 68a0db1d7da2 ("serial: mvebu-uart: add function to change baudrate") Cc: stable <stable@kernel.org> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Signed-off-by: Pali Rohár <pali@kernel.org> Link: https://lore.kernel.org/r/20220628100922.10717-1-pali@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-21serial: 8250: Fix PM usage_count for console handoverIlpo Järvinen2-5/+4
commit f9b11229b79c0fb2100b5bb4628a101b1d37fbf6 upstream. When console is enabled, univ8250_console_setup() calls serial8250_console_setup() before .dev is set to uart_port. Therefore, it will not call pm_runtime_get_sync(). Later, when the actual driver is going to take over univ8250_console_exit() is called. As .dev is already set, serial8250_console_exit() makes pm_runtime_put_sync() call with usage count being zero triggering PM usage count warning (extra debug for univ8250_console_setup(), univ8250_console_exit(), and serial8250_register_ports()): [ 0.068987] univ8250_console_setup ttyS0 nodev [ 0.499670] printk: console [ttyS0] enabled [ 0.717955] printk: console [ttyS0] printing thread started [ 1.960163] serial8250_register_ports assigned dev for ttyS0 [ 1.976830] printk: console [ttyS0] disabled [ 1.976888] printk: console [ttyS0] printing thread stopped [ 1.977073] univ8250_console_exit ttyS0 usage:0 [ 1.977075] serial8250 serial8250: Runtime PM usage count underflow! [ 1.977429] dw-apb-uart.6: ttyS0 at MMIO 0x4010006000 (irq = 33, base_baud = 115200) is a 16550A [ 1.977812] univ8250_console_setup ttyS0 usage:2 [ 1.978167] printk: console [ttyS0] printing thread started [ 1.978203] printk: console [ttyS0] enabled To fix the issue, call pm_runtime_get_sync() in serial8250_register_ports() as soon as .dev is set for an uart_port if it has console enabled. This problem became apparent only recently because 82586a721595 ("PM: runtime: Avoid device usage count underflows") added the warning printout. I confirmed this problem also occurs with v5.18 (w/o the warning printout, obviously). Fixes: bedb404e91bb ("serial: 8250_port: Don't use power management for kernel console") Cc: stable <stable@kernel.org> Tested-by: Tony Lindgren <tony@atomide.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/b4f428e9-491f-daf2-2232-819928dc276e@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-21serial: pl011: UPSTAT_AUTORTS requires .throttle/unthrottleIlpo Järvinen1-2/+21
commit 211565b100993c90b53bf40851eacaefc830cfe0 upstream. The driver must provide throttle and unthrottle in uart_ops when it sets UPSTAT_AUTORTS. Add them using existing stop_rx & enable_interrupts functions. Fixes: 2a76fa283098 (serial: pl011: Adopt generic flag to store auto RTS status) Cc: stable <stable@kernel.org> Cc: Lukas Wunner <lukas@wunner.de> Reported-by: Nuno Gonçalves <nunojpg@gmail.com> Tested-by: Nuno Gonçalves <nunojpg@gmail.com> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220614075637.8558-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-21serial: stm32: Clear prev values before setting RTS delaysIlpo Järvinen1-0/+2
commit 5c5f44e36217de5ead789ff25da71c31c2331c96 upstream. The code lacks clearing of previous DEAT/DEDT values. Thus, changing values on the fly results in garbage delays tending towards the maximum value as more and more bits are ORed together. (Leaving RS485 mode would have cleared the old values though). Fixes: 1bcda09d2910 ("serial: stm32: add support for RS485 hardware control mode") Cc: stable <stable@kernel.org> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/20220627150753.34510-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-21serial: 8250: fix return error code in serial8250_request_std_resource()Yi Yang1-1/+3
commit 6e690d54cfa802f939cefbd2fa2c91bd0b8bd1b6 upstream. If port->mapbase = NULL in serial8250_request_std_resource() , it need return a error code instead of 0. If uart_set_info() fail to request new regions by serial8250_request_std_resource() but the return value of serial8250_request_std_resource() is 0, The system incorrectly considers that the resource application is successful and does not attempt to restore the old setting. A null pointer reference is triggered when the port resource is later invoked. Signed-off-by: Yi Yang <yiyang13@huawei.com> Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/r/20220628083515.64138-1-yiyang13@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-21vt: fix memory overlapping when deleting chars in the bufferYangxi Xiang1-1/+1
commit 39cdb68c64d84e71a4a717000b6e5de208ee60cc upstream. A memory overlapping copy occurs when deleting a long line. This memory overlapping copy can cause data corruption when scr_memcpyw is optimized to memcpy because memcpy does not ensure its behavior if the destination buffer overlaps with the source buffer. The line buffer is not always broken, because the memcpy utilizes the hardware acceleration, whose result is not deterministic. Fix this problem by using replacing the scr_memcpyw with scr_memmovew. Fixes: 81732c3b2fed ("tty vt: Fix line garbage in virtual console on command line edition") Cc: stable <stable@kernel.org> Signed-off-by: Yangxi Xiang <xyangxi5@gmail.com> Link: https://lore.kernel.org/r/20220628093322.5688-1-xyangxi5@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-21tty: serial: samsung_tty: set dma burst_size to 1Chanho Park1-3/+2
commit f7e35e4bf1e8dc2c8cbd5e0955dc1bd58558dae0 upstream. The src_maxburst and dst_maxburst have been changed to 1 but the settings of the UCON register aren't changed yet. They should be changed as well according to the dmaengine slave config. Fixes: aa2f80e752c7 ("serial: samsung: fix maxburst parameter for DMA transactions") Cc: stable <stable@kernel.org> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Signed-off-by: Chanho Park <chanho61.park@samsung.com> Link: https://lore.kernel.org/r/20220627065113.139520-1-chanho61.park@samsung.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-29vt: drop old FONT ioctlsJiri Slaby2-187/+3
commit ff2047fb755d4415ec3c70ac799889371151796d upstream. Drop support for these ioctls: * PIO_FONT, PIO_FONTX * GIO_FONT, GIO_FONTX * PIO_FONTRESET As was demonstrated by commit 90bfdeef83f1 (tty: make FONTX ioctl use the tty pointer they were actually passed), these ioctls are not used from userspace, as: 1) they used to be broken (set up font on current console, not the open one) and racy (before the commit above) 2) KDFONTOP ioctl is used for years instead Note that PIO_FONTRESET is defunct on most systems as VGA_CONSOLE is set on them for ages. That turns on BROKEN_GRAPHICS_PROGRAMS which makes PIO_FONTRESET just return an error. We are removing KD_FONT_FLAG_OLD here as it was used only by these removed ioctls. kd.h header exists both in kernel and uapi headers, so we can remove the kernel one completely. Everyone includeing kd.h will now automatically get the uapi one. There are now unused definitions of the ioctl numbers and "struct consolefontdesc" in kd.h, but as it is a uapi header, I am not touching these. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-8-jslaby@suse.cz Cc: guodaxing <guodaxing@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-25serial: core: Initialize rs485 RTS polarity already on probeLukas Wunner1-22/+12
commit 2dd8a74fddd21b95dcc60a2d3c9eaec993419d69 upstream. RTS polarity of rs485-enabled ports is currently initialized on uart open via: tty_port_open() tty_port_block_til_ready() tty_port_raise_dtr_rts() # if (C_BAUD(tty)) uart_dtr_rts() uart_port_dtr_rts() There's at least three problems here: First, if no baud rate is set, RTS polarity is not initialized. That's the right thing to do for rs232, but not for rs485, which requires that RTS is deasserted unconditionally. Second, if the DeviceTree property "linux,rs485-enabled-at-boot-time" is present, RTS should be deasserted as early as possible, i.e. on probe. Otherwise it may remain asserted until first open. Third, even though RTS is deasserted on open and close, it may subsequently be asserted by uart_throttle(), uart_unthrottle() or uart_set_termios() because those functions aren't rs485-aware. (Only uart_tiocmset() is.) To address these issues, move RTS initialization from uart_port_dtr_rts() to uart_configure_port(). Prevent subsequent modification of RTS polarity by moving the existing rs485 check from uart_tiocmget() to uart_update_mctrl(). That way, RTS is initialized on probe and then remains unmodified unless the uart transmits data. If rs485 is enabled at runtime (instead of at boot) through a TIOCSRS485 ioctl(), RTS is initialized by the uart driver's ->rs485_config() callback and then likewise remains unmodified. The PL011 driver initializes RTS on uart open and prevents subsequent modification in its ->set_mctrl() callback. That code is obsoleted by the present commit, so drop it. Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Su Bao Cheng <baocheng.su@siemens.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Link: https://lore.kernel.org/r/2d2acaf3a69e89b7bf687c912022b11fd29dfa1e.1642909284.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-22serial: 8250: Store to lsr_save_flags after lsr readIlpo Järvinen1-0/+2
commit be03b0651ffd8bab69dfd574c6818b446c0753ce upstream. Not all LSR register flags are preserved across reads. Therefore, LSR readers must store the non-preserved bits into lsr_save_flags. This fix was initially mixed into feature commit f6f586102add ("serial: 8250: Handle UART without interrupt on TEMT using em485"). However, that feature change had a flaw and it was reverted to make room for simpler approach providing the same feature. The embedded fix got reverted with the feature change. Re-add the lsr_save_flags fix and properly mark it's a fix. Link: https://lore.kernel.org/all/1d6c31d-d194-9e6a-ddf9-5f29af829f3@linux.intel.com/T/#m1737eef986bd20cf19593e344cebd7b0244945fc Fixes: e490c9144cfa ("tty: Add software emulated RS485 support for 8250") Cc: stable <stable@kernel.org> Acked-by: Uwe Kleine-König <u.kleine-koenig@penugtronix.de> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://lore.kernel.org/r/f4d774be-1437-a550-8334-19d8722ab98c@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-22tty: goldfish: Fix free_irq() on removeVincent Whitchurch1-1/+1
[ Upstream commit 499e13aac6c762e1e828172b0f0f5275651d6512 ] Pass the correct dev_id to free_irq() to fix this splat when the driver is unbound: WARNING: CPU: 0 PID: 30 at kernel/irq/manage.c:1895 free_irq Trying to free already-free IRQ 65 Call Trace: warn_slowpath_fmt free_irq goldfish_tty_remove platform_remove device_remove device_release_driver_internal device_driver_detach unbind_store drv_attr_store ... Fixes: 465893e18878e119 ("tty: goldfish: support platform_device with id -1") Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Link: https://lore.kernel.org/r/20220609141704.1080024-1-vincent.whitchurch@axis.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14serial: msm_serial: disable interrupts in __msm_console_write()John Ogness1-0/+5
[ Upstream commit aabdbb1b7a5819e18c403334a31fb0cc2c06ad41 ] __msm_console_write() assumes that interrupts are disabled, but with threaded console printers it is possible that the write() callback of the console is called with interrupts enabled. Explicitly disable interrupts using local_irq_save() to preserve the assumed context. Reported-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: John Ogness <john.ogness@linutronix.de> Link: https://lore.kernel.org/r/20220506213324.470461-1-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14sysrq: do not omit current cpu when showing backtrace of all active CPUsChangbin Du1-4/+9
[ Upstream commit 5390e7f46b9d5546d45a83e6463bc656678b1d0e ] The backtrace of current CPU also should be printed as it is active. This change add stack trace for current CPU and print a hint for idle CPU for the generic workqueue based printing. (x86 already does this) Now it looks like below: [ 279.401567] sysrq: Show backtrace of all active CPUs [ 279.407234] sysrq: CPU5: [ 279.407505] Call Trace: [ 279.408789] [<ffffffff8000606c>] dump_backtrace+0x2c/0x3a [ 279.411698] [<ffffffff800060ac>] show_stack+0x32/0x3e [ 279.411809] [<ffffffff80542258>] sysrq_handle_showallcpus+0x4c/0xc6 [ 279.411929] [<ffffffff80542f16>] __handle_sysrq+0x106/0x26c [ 279.412034] [<ffffffff805436a8>] write_sysrq_trigger+0x64/0x74 [ 279.412139] [<ffffffff8029cd48>] proc_reg_write+0x8e/0xe2 [ 279.412252] [<ffffffff8021a8f8>] vfs_write+0x90/0x2be [ 279.412362] [<ffffffff8021acd2>] ksys_write+0xa6/0xce [ 279.412467] [<ffffffff8021ad24>] sys_write+0x2a/0x38 [ 279.412689] [<ffffffff80003ff8>] ret_from_syscall+0x0/0x2 [ 279.417173] sysrq: CPU6: backtrace skipped as idling [ 279.417185] sysrq: CPU4: backtrace skipped as idling [ 279.417187] sysrq: CPU0: backtrace skipped as idling [ 279.417181] sysrq: CPU7: backtrace skipped as idling [ 279.417190] sysrq: CPU1: backtrace skipped as idling [ 279.417193] sysrq: CPU3: backtrace skipped as idling [ 279.417219] sysrq: CPU2: [ 279.419179] Call Trace: [ 279.419440] [<ffffffff8000606c>] dump_backtrace+0x2c/0x3a [ 279.419782] [<ffffffff800060ac>] show_stack+0x32/0x3e [ 279.420015] [<ffffffff80542b30>] showacpu+0x5c/0x96 [ 279.420317] [<ffffffff800ba71c>] flush_smp_call_function_queue+0xd6/0x218 [ 279.420569] [<ffffffff800bb438>] generic_smp_call_function_single_interrupt+0x14/0x1c [ 279.420798] [<ffffffff800079ae>] handle_IPI+0xaa/0x13a [ 279.421024] [<ffffffff804dcb92>] riscv_intc_irq+0x56/0x70 [ 279.421274] [<ffffffff80a05b70>] generic_handle_arch_irq+0x6a/0xfa [ 279.421518] [<ffffffff80004006>] ret_from_exception+0x0/0x10 [ 279.421750] [<ffffffff80096492>] rcu_idle_enter+0x16/0x1e Signed-off-by: Changbin Du <changbin.du@gmail.com> Link: https://lore.kernel.org/r/20220117154300.2808-1-changbin.du@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14drivers: tty: serial: Fix deadlock in sa1100_set_termios()Duoming Zhou1-2/+2
[ Upstream commit 62b2caef400c1738b6d22f636c628d9f85cd4c4c ] There is a deadlock in sa1100_set_termios(), which is shown below: (Thread 1) | (Thread 2) | sa1100_enable_ms() sa1100_set_termios() | mod_timer() spin_lock_irqsave() //(1) | (wait a time) ... | sa1100_timeout() del_timer_sync() | spin_lock_irqsave() //(2) (wait timer to stop) | ... We hold sport->port.lock in position (1) of thread 1 and use del_timer_sync() to wait timer to stop, but timer handler also need sport->port.lock in position (2) of thread 2. As a result, sa1100_set_termios() will block forever. This patch moves del_timer_sync() before spin_lock_irqsave() in order to prevent the deadlock. Signed-off-by: Duoming Zhou <duoming@zju.edu.cn> Link: https://lore.kernel.org/r/20220417111626.7802-1-duoming@zju.edu.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14tty: Fix a possible resource leak in icom_probeHuang Guobin1-1/+1
[ Upstream commit ee157a79e7c82b01ae4c25de0ac75899801f322c ] When pci_read_config_dword failed, call pci_release_regions() and pci_disable_device() to recycle the resource previously allocated. Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Huang Guobin <huangguobin4@huawei.com> Link: https://lore.kernel.org/r/20220331091005.3290753-1-huangguobin4@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-14tty: synclink_gt: Fix null-pointer-dereference in slgt_clean()Zheyu Ma1-0/+2
[ Upstream commit 689ca31c542687709ba21ec2195c1fbce34fd029 ] When the driver fails at alloc_hdlcdev(), and then we remove the driver module, we will get the following splat: [ 25.065966] general protection fault, probably for non-canonical address 0xdffffc0000000182: 0000 [#1] PREEMPT SMP KASAN PTI [ 25.066914] KASAN: null-ptr-deref in range [0x0000000000000c10-0x0000000000000c17] [ 25.069262] RIP: 0010:detach_hdlc_protocol+0x2a/0x3e0 [ 25.077709] Call Trace: [ 25.077924] <TASK> [ 25.078108] unregister_hdlc_device+0x16/0x30 [ 25.078481] slgt_cleanup+0x157/0x9f0 [synclink_gt] Fix this by checking whether the 'info->netdev' is a null pointer first. Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Zheyu Ma <zheyuma97@gmail.com> Link: https://lore.kernel.org/r/20220410114814.3920474-1-zheyuma97@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>