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2021-01-15tty: vcc: Drop unnecessary if blockUwe Kleine-König
If vcc_probe() succeeded dev_set_drvdata() is called with a non-NULL value, and if vcc_probe() failed vcc_remove() isn't called. So there is no way dev_get_drvdata() can return NULL in vcc_remove() and the check can just go away. Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20210114175718.137483-3-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-15tty: hvcs: Drop unnecessary if blockUwe Kleine-König
If hvcs_probe() succeeded dev_set_drvdata() is called with a non-NULL value, and if hvcs_probe() failed hvcs_remove() isn't called. So there is no way dev_get_drvdata() can return NULL in hvcs_remove() and the check can just go away. Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20210114175718.137483-2-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-13tty: serial: owl: Add support for kernel debuggerCristian Ciocaltea
Implement 'poll_put_char' and 'poll_get_char' callbacks in struct 'owl_uart_ops' that enables OWL UART to be used for kernel debugging over serial line. Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@gmail.com> Link: https://lore.kernel.org/r/026543195b9aeefb339d90abc5660a6ac7463c63.1610484108.git.cristian.ciocaltea@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-08Revert "init/console: Use ttynull as a fallback when there is no console"Petr Mladek
This reverts commit 757055ae8dedf5333af17b3b5b4b70ba9bc9da4e. The commit caused that ttynull was used as the default console on several systems[1][2][3]. As a result, the console was blank even when a better alternative existed. It happened when there was no console configured on the command line and ttynull_init() was the first initcall calling register_console(). Or it happened when /dev/ did not exist when console_on_rootfs() was called. It was not able to open /dev/console even though a console driver was registered. It tried to add ttynull console but it obviously did not help. But ttynull became the preferred console and was used by /dev/console when it was available later. The commit tried to fix a historical problem that have been there for ages. The primary motivation was the commit 3cffa06aeef7ece30f6 ("printk/console: Allow to disable console output by using console="" or console=null"). It provided a clean solution for a workaround that was widely used and worked only by chance. This revert causes that the console="" or console=null command line options will again work only by chance. These options will cause that a particular console will be preferred and the default (tty) ones will not get enabled. There will be no console registered at all. As a result there won't be stdin, stdout, and stderr for the init process. But it worked exactly this way even before. The proper solution has to fulfill many conditions: + Register ttynull only when explicitly required or as the ultimate fallback. + ttynull should get associated with /dev/console but it must not become preferred console when used as a fallback. Especially, it must still be possible to replace it by a better console later. Such a change requires clean up of the register_console() code. Otherwise, it would be even harder to follow. Especially, the use of has_preferred_console and CON_CONSDEV flag is tricky. The clean up is risky. The ordering of consoles is not well defined. And any changes tend to break existing user settings. Do the revert at the least risky solution for now. [1] https://lore.kernel.org/linux-kselftest/20201221144302.GR4077@smile.fi.intel.com/ [2] https://lore.kernel.org/lkml/d2a3b3c0-e548-7dd1-730f-59bc5c04e191@synopsys.com/ [3] https://patchwork.ozlabs.org/project/linux-um/patch/20210105120128.10854-1-thomas@m3y3r.de/ Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reported-by: Vineet Gupta <vgupta@synopsys.com> Reported-by: Thomas Meyer <thomas@m3y3r.de> Signed-off-by: Petr Mladek <pmladek@suse.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-01-07riscv: Fix sifive serial driverDamien Le Moal
Setup the port uartclk in sifive_serial_probe() so that the base baud rate is correctly printed during device probe instead of always showing "0". I.e. the probe message is changed from 38000000.serial: ttySIF0 at MMIO 0x38000000 (irq = 1, base_baud = 0) is a SiFive UART v0 to the correct: 38000000.serial: ttySIF0 at MMIO 0x38000000 (irq = 1, base_baud = 115200) is a SiFive UART v0 Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com> Acked-by: Palmer Dabbelt <palmerdabbelt@google.com> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-07tty: Protect disc_data in n_tty_close and n_tty_flush_bufferYan.Gao
n_tty_flush_buffer can happen in parallel with n_tty_close that the tty->disc_data will be set to NULL. n_tty_flush_buffer accesses tty->disc_data, so we must prevent n_tty_close clear tty->disc_data while n_tty_flush_buffer has a non-NULL view of tty->disc_data. So we need to make sure that accesses to disc_data are atomic using tty->termios_rwsem. There is an example I meet: When n_tty_flush_buffer accesses tty struct, the disc_data is right. However, then reset_buffer_flags accesses tty->disc_data, disc_data become NULL, So kernel crash when accesses tty->disc_data->real_tail. I guess there could be another thread change tty->disc_data to NULL, and during N_TTY line discipline, n_tty_close will set tty->disc_data to be NULL. So use tty->termios_rwsem to protect disc_data between close and flush_buffer. IP: reset_buffer_flags+0x9/0xf0 PGD 0 P4D 0 Oops: 0002 [#1] SMP CPU: 23 PID: 2087626 Comm: (agetty) Kdump: loaded Tainted: G Hardware name: UNISINSIGHT X3036P-G3/ST01M2C7S, BIOS 2.00.13 01/11/2019 task: ffff9c4e9da71e80 task.stack: ffffb30cfe898000 RIP: 0010:reset_buffer_flags+0x9/0xf0 RSP: 0018:ffffb30cfe89bca8 EFLAGS: 00010246 RAX: ffff9c4e9da71e80 RBX: ffff9c368d1bac00 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffff9c4ea17b50f0 RDI: 0000000000000000 RBP: ffffb30cfe89bcc8 R08: 0000000000000100 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000000 R12: ffff9c368d1bacc0 R13: ffff9c20cfd18428 R14: ffff9c4ea17b50f0 R15: ffff9c368d1bac00 FS: 00007f9fbbe97940(0000) GS:ffff9c375c740000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000002260 CR3: 0000002f72233003 CR4: 00000000007606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: ? n_tty_flush_buffer+0x2a/0x60 tty_buffer_flush+0x76/0x90 tty_ldisc_flush+0x22/0x40 vt_ioctl+0x5a7/0x10b0 ? n_tty_ioctl_helper+0x27/0x110 tty_ioctl+0xef/0x8c0 do_vfs_ioctl+0xa7/0x5e0 ? __audit_syscall_entry+0xaf/0x100 ? syscall_trace_enter+0x1d0/0x2b0 SyS_ioctl+0x79/0x90 do_syscall_64+0x6c/0x1b0 entry_SYSCALL64_slow_path+0x25/0x25 n_tty_flush_buffer --->tty->disc_data is OK ->reset_buffer_flags -->tty->disc_data is NULL Signed-off-by: Yan.Gao <gao.yanB@h3c.com> Reviewed-by: Xianting Tian <tian.xianting@h3c.com> Link: https://lore.kernel.org/r/20201210022507.30729-1-gao.yanB@h3c.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07drivers:tty:pty: Fix a race causing data loss on closeCorey Minyard
Remove the tty_vhangup() from the pty code and just release the redirect. The tty_vhangup() results in data loss and data out of order issues. If you write to a pty master an immediately close the pty master, the receiver might get a chunk of data dropped, but then receive some later data. That's obviously something rather unexpected for a user. It certainly confused my test program. It turns out that tty_vhangup() on the slave pty gets called from pty_close(), and that causes the data on the slave side to be flushed, but due to races more data can be copied into the slave side's buffer after that. Consider the following sequence: thread1 thread2 thread3 ------- ------- ------- | |-write data into buffer, | | n_tty buffer is filled | | along with other buffers | |-pty_close(master) | |--tty_vhangup(slave) | |---tty_ldisc_hangup() | |----n_tty_flush_buffer() | |-----reset_buffer_flags() |-n_tty_read() | |--up_read(&tty->termios_rwsem); | |------down_read(&tty->termios_rwsem) | |------clear n_tty buffer contents | |------up_read(&tty->termios_rwsem) |--tty_buffer_flush_work() | |--schedules work calling | | flush_to_ldisc() | | |-flush_to_ldisc() | |--receive_buf() | |---tty_port_default_receive_buf() | |----tty_ldisc_receive_buf() | |-----n_tty_receive_buf2() | |------n_tty_receive_buf_common() | |-------down_read(&tty->termios_rwsem) | |-------__receive_buf() | | copies data into n_tty buffer | |-------up_read(&tty->termios_rwsem) |--down_read(&tty->termios_rwsem) |--copy buffer data to user >From this sequence, you can see that thread2 writes to the buffer then only clears the part of the buffer in n_tty. The n_tty receive buffer code then copies more data into the n_tty buffer. But part of the vhangup, releasing the redirect, is still required to avoid issues with consoles running on pty slaves. So do that. As far as I can tell, that is all that should be required. Signed-off-by: Corey Minyard <cminyard@mvista.com> Link: https://lore.kernel.org/r/20201124004902.1398477-3-minyard@acm.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07tty: Export redirect releaseCorey Minyard
This will be required by the pty code when it removes tty_vhangup() on master close. Signed-off-by: Corey Minyard <cminyard@mvista.com> Link: https://lore.kernel.org/r/20201124004902.1398477-2-minyard@acm.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07serial: stm32: update transmission complete error message in shutdownErwan Le Ray
The transmission complete error message provides the status of the ISR_USART_TC bit. This bit, when set, indicates that the transmission has not been completed. The bit status indication is not a very understandable information. The error message sent on console should indicate that the transmission is not complete, instead of providing USART_TC bit status. Update the error message and add a comment for better understanding. Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210106162203.28854-9-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07serial: stm32: clean probe and remove port deinitErwan Le Ray
Clean probe and remove port deinit by moving clk_disable_unprepare in a new dedicated deinit_port function. Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Signed-off-by: Etienne Carriere <etienne.carriere@foss.st.com> Link: https://lore.kernel.org/r/20210106162203.28854-8-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07serial: stm32: update conflicting RTS/CTS config commentErwan Le Ray
The comment for conflicting RTS/CTS config refers to "st, hw-flow-ctrl", but this property is deprecated since the generic RTS/CTS property has been introduced by the patch 'serial: stm32: Use generic DT binding for announcing RTS/CTS lines'. Update the comment to refer to both generic and deprecated RTS/CTS properties. Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210106162203.28854-7-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07serial: stm32: add authorErwan Le Ray
Update email address add new author in authors list. Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210106162203.28854-5-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07serial: stm32: add "_usart" prefix in functions nameErwan Le Ray
Adds the prefix "_usart" in the name of stm32 usart functions in order to ease the usage of kernel trace and tools, such as f-trace. Allows to trace "stm32_usart_*" functions with f-trace. Without this patch, all the driver functions needs to be added manually in f-trace filter. Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Signed-off-by: Valentin Caron <valentin.caron@foss.st.com> Link: https://lore.kernel.org/r/20210106162203.28854-4-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07serial: stm32: fix code cleaning warnings and checksErwan Le Ray
Fixes checkpatch --strict warnings and checks: - checkpatch --strict "Unnecessary parentheses" - checkpatch --strict "Blank lines aren't necessary before a close brace - checkpatch --strict "Alignment should match open parenthesis" - checkpatch --strict "Please don't use multiple blank lines" - checkpatch --strict "Comparison to NULL could be written ..." - visual check code ordering warning Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210106162203.28854-3-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07serial: stm32: fix DMA initialization error handlingErwan Le Ray
DMA initialization error handling is not properly implemented in the driver. Fix DMA initialization error handling by: - moving TX DMA descriptor request error handling in a new dedicated fallback_err label - adding error handling to TX DMA descriptor submission - adding error handling to RX DMA descriptor submission This patch depends on '24832ca3ee85 ("tty: serial: stm32-usart: Remove set but unused 'cookie' variables")' which unfortunately doesn't include a "Fixes" tag. Fixes: 3489187204eb ("serial: stm32: adding dma support") Signed-off-by: Erwan Le Ray <erwan.leray@foss.st.com> Link: https://lore.kernel.org/r/20210106162203.28854-2-erwan.leray@foss.st.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07tty_port: drop last traces of low_latencyJiri Slaby
The main purpose of tty_port::low_latency was removed in commit a9c3f68f3cd8 (tty: Fix low_latency BUG) back in 2014. It was left in place for drivers as an optional tune knob. But only one driver has been using it until the previous commit. So remove this misconcept completely, given there are no users. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-11-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07tty: cpm_uart, use port->flags instead of low_latencyJiri Slaby
This is the only in-kernel user of tty_port::low_latency. Switch this last one to test uport->flags directly as tty_port::low_latency is going away in the next patch. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-10-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07vt: drop old FONT ioctlsJiri Slaby
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 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07vt/consolemap: do font sum unsignedJiri Slaby
The constant 20 makes the font sum computation signed which can lead to sign extensions and signed wraps. It's not much of a problem as we build with -fno-strict-overflow. But if we ever decide not to, be ready, so switch the constant to unsigned. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-7-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-078250_tegra: clean up tegra_uart_handle_breakJiri Slaby
* switch "do { A; } while (1)" to "while (1) { A; }" * switch "if (A) B; else break;" to "if (!A) break; B;" * remove unused assignment from p->serial_in() to status Objdump -d shows no difference. Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Jonathan Hunter <jonathanh@nvidia.com> Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-6-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07tty: pty, remove BUG_ON from pty_closeJiri Slaby
tty->ops->close is always called with a valid tty, so the BUG_ON cannot trigger. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-5-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07vt: keyboard, defkeymap.c_shipped, approach the unicode tableJiri Slaby
Commit 5ce2087ed0eb (Fix default compose table initialization) fixed unicode table so that the values are not sign extended. The upstream (kbd package) chose a different approach. They use hexadecimal values. So use the same, so that the output of loadkeys and our shipped file correspond more to each other. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-4-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07vt: keyboard, defkeymap.c_shipped, approach the definitionsJiri Slaby
loadkeys (from kbd) generates 'unsigned short' instead of 'u_short' since 2.0.3. It also marks maps as 'static' for longer than kbd's history. So adapt the shipped defkeymap.c to conform more to loadkeys output. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-3-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07vt: keyboard, make keyboard_tasklet localJiri Slaby
Now that the last extern user of the tasklet (set_leds) is in keyboard.c, we can make keyboard_tasklet local to this unit too. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-2-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-07vt: move set_leds to keyboard.cJiri Slaby
set_leds and compute_shiftstate are called from a single place in vt.c. Let's combine these two into vt_set_leds_compute_shiftstate. This allows for making keyboard_tasklet local in the next patch. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Link: https://lore.kernel.org/r/20210105120239.28031-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-28serial: mvebu-uart: fix tx lost characters at power offPali Rohár
Commit c685af1108d7 ("serial: mvebu-uart: fix tx lost characters") fixed tx lost characters at low baud rates but started causing tx lost characters when kernel is going to power off or reboot. TX_EMP tells us when transmit queue is empty therefore all characters were transmitted. TX_RDY tells us when CPU can send a new character. Therefore we need to use different check prior transmitting new character and different check after all characters were sent. This patch splits polling code into two functions: wait_for_xmitr() which waits for TX_RDY and wait_for_xmite() which waits for TX_EMP. When rebooting A3720 platform without this patch on UART is print only: [ 42.699� And with this patch on UART is full output: [ 39.530216] reboot: Restarting system Fixes: c685af1108d7 ("serial: mvebu-uart: fix tx lost characters") Signed-off-by: Pali Rohár <pali@kernel.org> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20201223191931.18343-1-pali@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-28tty: serial: icom: Use DEFINE_SPINLOCK() for spinlockZheng Yongjun
spinlock can be initialized automatically with DEFINE_SPINLOCK() rather than explicitly calling spin_lock_init(). Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com> Link: https://lore.kernel.org/r/20201223141438.889-1-zhengyongjun3@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-28tty: serial: cpm_uart: Add udbg support for enabling xmonChristophe Leroy
In order to use xmon with powerpc 8xx, the serial driver must provide udbg_putc() and udpb_getc(). Provide them via cpm_put_poll_char() and cpm_get_poll_char(). This requires CONFIG_CONSOLE_POLL. Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Link: https://lore.kernel.org/r/e4471bf81089252470efb3eed735d71a5b32adbd.1608716197.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-28tty/serial/lantiq: convert comma to semicolonZheng Yongjun
Replace a comma between expression statements by a semicolon. Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com> Link: https://lore.kernel.org/r/20201214133755.3945-1-zhengyongjun3@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-28tty/serial/imx: convert comma to semicolonZheng Yongjun
Replace a comma between expression statements by a semicolon. Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com> Link: https://lore.kernel.org/r/20201214133719.3893-1-zhengyongjun3@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-28tty: new helper function tty_get_icount()Uwe Kleine-König
For a given struct tty_struct this yields the corresponding statistics about sent and received characters (and some more) which is needed to implement an LED trigger for tty devices. The new function is then used to simplify tty_tiocgicount(). Reviewed-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20201218104246.591315-3-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-28tty: rename tty_kopen() and add new function tty_kopen_shared()Uwe Kleine-König
Introduce a new function tty_kopen_shared() that yields a struct tty_struct. The semantic difference to tty_kopen() is that the tty is expected to be used already. So rename tty_kopen() to tty_kopen_exclusive() for clearness, adapt the single user and put the common code in a new static helper function. tty_kopen_shared is to be used to implement an LED trigger for tty devices in one of the next patches. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20201218104246.591315-2-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-17Merge tag 'for-linus' of git://github.com/openrisc/linuxLinus Torvalds
Pull OpenRISC updates from Stafford Horne: - New drivers and OpenRISC support for the LiteX platform - A bug fix to support userspace gdb debugging - Fixes one compile issue with blk-iocost * tag 'for-linus' of git://github.com/openrisc/linux: openrisc: add local64.h to fix blk-iocost build openrisc: fix trap for debugger breakpoint signalling openrisc: add support for LiteX drivers/tty/serial: add LiteUART driver dt-bindings: serial: document LiteUART bindings drivers/soc/litex: add LiteX SoC Controller driver dt-bindings: soc: document LiteX SoC Controller bindings dt-bindings: vendor: add vendor prefix for LiteX
2020-12-16Merge tag 'printk-for-5.11' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux Pull printk updates from Petr Mladek: - Finally allow parallel writes and reads into/from the lockless ringbuffer. But it is not a complete solution. Readers are still serialized against each other. And nested writes are still prevented by printk_safe per-CPU buffers. - Use ttynull as the ultimate fallback for /dev/console. - Officially allow disabling console output by using console="" or console=null - A few code cleanups * tag 'printk-for-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: printk: remove logbuf_lock writer-protection of ringbuffer printk: inline log_output(),log_store() in vprintk_store() printk: remove obsolete dead assignment printk/console: Allow to disable console output by using console="" or console=null init/console: Use ttynull as a fallback when there is no console printk: ringbuffer: Reference text_data_ring directly in callees.
2020-12-15Merge tag 'tty-5.11-rc1' of ↵Linus Torvalds
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 patches for 5.11-rc1. Nothing major at all, some cleanups and some driver removals, always a nice sign: - build warning cleanups - vt locking and logic unwinding and cleanups - tiny serial driver fixes and updates - removal of the synclink serial driver as it's no longer needed - removal of dead termiox code All of this has been in linux-next for a while with no reported issues" * tag 'tty-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (89 commits) serial: 8250_pci: Drop bogus __refdata annotation tty: serial: meson: enable console as module serial: 8250_omap: Avoid FIFO corruption caused by MDR1 access serial: imx: Move imx_uart_probe_dt() content into probe() serial: imx: Remove unneeded of_device_get_match_data() NULL check tty: Fix whitespace inconsistencies in vt_io_ioctl serial_core: Check for port state when tty is in error state dt-bindings: serial: Update DT binding docs to support SiFive FU740 SoC tty: use const parameters in port-flag accessors tty: use assign_bit() in port-flag accessors earlycon: drop semicolon from earlycon macro tty: Remove dead termiox code tty/serial/imx: Enable TXEN bit in imx_poll_init(). tty : serial: jsm: Fixed file by adding spacing tty: serial: uartlite: Support probe deferral earlycon: simplify earlycon-table implementation tty: serial: bcm63xx: lower driver dependencies serial: mxs-auart: Remove unneeded platform_device_id serial: 8250-mtk: Fix reference leak in mtk8250_probe serial: imx: Remove unused .id_table support ...
2020-12-14Merge tag 'm68k-for-v5.11-tag1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k Pull m68k updates from Geert Uytterhoeven: - fix WARNING splat in pmac_zilog driver - fix ADB input device regression - assume maintainership for adb-iop and via-macii - minor fixes and improvements - defconfig updates * tag 'm68k-for-v5.11-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k: MAINTAINERS: Update m68k Mac entry macintosh/adb-iop: Send correct poll command macintosh/adb-iop: Always wait for reply message from IOP m68k: Fix WARNING splat in pmac_zilog driver m68k: Add a missing ELF_DETAILS in link script m68k: Drop redundant NOTES in link script m68k: mac: Update Kconfig help m68k: mac: Remove redundant VIA register writes m68k: mac: Remove dead code m68k: mac: Refactor iop_preinit() and iop_init() m68k: defconfig: Enable KUnit tests m68k: defconfig: Update defconfigs for v5.10-rc1 m68k: Remove unused mach_max_dma_address m68k: Avoid xchg() warning
2020-12-14Merge branch 'for-5.11-null-console' into for-linusPetr Mladek
2020-12-11serial: 8250_pci: Drop bogus __refdata annotationGeert Uytterhoeven
Since commit d73dfc6a4199e0e3 ("serial: 8250_pci: remove __devexit usage") in v3.9, the 8250/16550 PCI serial driver no longer has any code or data located in initmem, hence there is no need to annotate the pci_serial_quirks structure with __refdata. Drop the annotation, to avoid suppressing future section warnings. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20201211133907.2970460-1-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-11tty: serial: meson: enable console as moduleKevin Hilman
Enable serial driver to be built as a module. To do so, init the console support on driver/module load instead of using console_initcall(). Signed-off-by: Kevin Hilman <khilman@baylibre.com> Link: https://lore.kernel.org/r/20201211005744.12855-1-khilman@baylibre.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-10serial: 8250_omap: Avoid FIFO corruption caused by MDR1 accessAlexander Sverdlin
It has been observed that once per 300-1300 port openings the first transmitted byte is being corrupted on AM3352 ("v" written to FIFO appeared as "e" on the wire). It only happened if single byte has been transmitted right after port open, which means, DMA is not used for this transfer and the corruption never happened afterwards. Therefore I've carefully re-read the MDR1 errata (link below), which says "when accessing the MDR1 registers that causes a dummy under-run condition that will freeze the UART in IrDA transmission. In UART mode, this may corrupt the transferred data". Strictly speaking, omap_8250_mdr1_errataset() performs a read access and if the value is the same as should be written, exits without errata-recommended FIFO reset. A brief check of the serial_omap_mdr1_errataset() from the competing omap-serial driver showed it has no read access of MDR1. After removing the read access from omap_8250_mdr1_errataset() the data corruption never happened any more. Link: https://www.ti.com/lit/er/sprz360i/sprz360i.pdf Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver") Cc: stable@vger.kernel.org Signed-off-by: Alexander Sverdlin <alexander.sverdlin@gmail.com> Link: https://lore.kernel.org/r/20201210055257.1053028-1-alexander.sverdlin@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-10serial: imx: Move imx_uart_probe_dt() content into probe()Fabio Estevam
Now that the driver only probes via devicetree, we can move the content of imx_uart_probe_dt() directly into imx_uart_probe() to make the code simpler. Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Fabio Estevam <festevam@gmail.com> Link: https://lore.kernel.org/r/20201209214712.15247-1-festevam@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09serial: imx: Remove unneeded of_device_get_match_data() NULL checkFabio Estevam
Since 5.10-rc1 i.MX is a devicetree-only platform and the NULL check on of_device_get_match_data() is no longer needed. This check was only needed when this driver supported both DT and non-DT platforms. Remove the unneeded of_device_get_match_data() NULL check. Signed-off-by: Fabio Estevam <festevam@gmail.com> Link: https://lore.kernel.org/r/20201126124643.3371-1-festevam@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09tty: Fix whitespace inconsistencies in vt_io_ioctlYan.Gao
Replaces spaces with tabs for indentation. Signed-off-by: Yan.Gao <gao.yanB@h3c.com> Link: https://lore.kernel.org/r/20201209030551.48029-1-gao.yanB@h3c.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-09serial_core: Check for port state when tty is in error stateAlexey Kardashevskiy
At the moment opening a serial device node (such as /dev/ttyS3) succeeds even if there is no actual serial device behind it. Reading/writing/ioctls fail as expected because the uart port is not initialized (the type is PORT_UNKNOWN) and the TTY_IO_ERROR error state bit is set fot the tty. However setting line discipline does not have these checks 8250_port.c (8250 is the default choice made by univ8250_console_init()). As the result of PORT_UNKNOWN, uart_port::iobase is NULL which a platform translates onto some address accessing which produces a crash like below. This adds tty_port_initialized() to uart_set_ldisc() to prevent the crash. Found by syzkaller. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Link: https://lore.kernel.org/r/20201203055834.45838-1-aik@ozlabs.ru Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-07Merge 5.10-rc7 into tty-nextGreg Kroah-Hartman
We want the tty fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-04tty: Fix ->session lockingJann Horn
Currently, locking of ->session is very inconsistent; most places protect it using the legacy tty mutex, but disassociate_ctty(), __do_SAK(), tiocspgrp() and tiocgsid() don't. Two of the writers hold the ctrl_lock (because they already need it for ->pgrp), but __proc_set_tty() doesn't do that yet. On a PREEMPT=y system, an unprivileged user can theoretically abuse this broken locking to read 4 bytes of freed memory via TIOCGSID if tiocgsid() is preempted long enough at the right point. (Other things might also go wrong, especially if root-only ioctls are involved; I'm not sure about that.) Change the locking on ->session such that: - tty_lock() is held by all writers: By making disassociate_ctty() hold it. This should be fine because the same lock can already be taken through the call to tty_vhangup_session(). The tricky part is that we need to shorten the area covered by siglock to be able to take tty_lock() without ugly retry logic; as far as I can tell, this should be fine, since nothing in the signal_struct is touched in the `if (tty)` branch. - ctrl_lock is held by all writers: By changing __proc_set_tty() to hold the lock a little longer. - All readers that aren't holding tty_lock() hold ctrl_lock: By adding locking to tiocgsid() and __do_SAK(), and expanding the area covered by ctrl_lock in tiocspgrp(). Cc: stable@kernel.org Signed-off-by: Jann Horn <jannh@google.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-04tty: Fix ->pgrp locking in tiocspgrp()Jann Horn
tiocspgrp() takes two tty_struct pointers: One to the tty that userspace passed to ioctl() (`tty`) and one to the TTY being changed (`real_tty`). These pointers are different when ioctl() is called with a master fd. To properly lock real_tty->pgrp, we must take real_tty->ctrl_lock. This bug makes it possible for racing ioctl(TIOCSPGRP, ...) calls on both sides of a PTY pair to corrupt the refcount of `struct pid`, leading to use-after-free errors. Fixes: 47f86834bbd4 ("redo locking of tty->pgrp") CC: stable@kernel.org Signed-off-by: Jann Horn <jannh@google.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-04tty: Remove dead termiox codeJann Horn
set_termiox() and the TCGETX handler bail out with -EINVAL immediately if ->termiox is NULL, but there are no code paths that can set ->termiox to a non-NULL pointer; and no such code paths seem to have existed since the termiox mechanism was introduced back in commit 1d65b4a088de ("tty: Add termiox") in v2.6.28. Similarly, no driver actually implements .set_termiox; and it looks like no driver ever has. Delete this dead code; but leave the definition of struct termiox in the UAPI headers intact. Signed-off-by: Jann Horn <jannh@google.com> Link: https://lore.kernel.org/r/20201203020331.2394754-1-jannh@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-04tty/serial/imx: Enable TXEN bit in imx_poll_init().Mingrui Ren
As described in Documentation, poll_init() is called by kgdb to initialize hardware which supports both poll_put_char() and poll_get_char(). It's necessary to enable TXEN bit, otherwise, it will cause hardware fault and kernel panic when calling imx_poll_put_char(). Generally, if use /dev/ttymxc0 as kgdb console as well as system console, ttymxc0 is initialized early by system console which does enable TXEN bit.But when use /dev/ttymxc1 as kgbd console, ttymxc1 is only initialized by imx_poll_init() cannot enable the TXEN bit, which will cause kernel panic. Signed-off-by: Mingrui Ren <jiladahe1997@gmail.com> Link: https://lore.kernel.org/r/20201202072543.151-1-972931182@qq.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-04tty : serial: jsm: Fixed file by adding spacingClement Smith
Fixed a coding style issue Signed-off-by: Clement Smith <rclemsmith@gmail.com> Link: https://lore.kernel.org/r/20201202060916.34130-1-rclemsmith@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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