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* Merge branch 'syscalls-next' of ↵Linus Torvalds2018-04-022-4/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux Pull removal of in-kernel calls to syscalls from Dominik Brodowski: "System calls are interaction points between userspace and the kernel. Therefore, system call functions such as sys_xyzzy() or compat_sys_xyzzy() should only be called from userspace via the syscall table, but not from elsewhere in the kernel. At least on 64-bit x86, it will likely be a hard requirement from v4.17 onwards to not call system call functions in the kernel: It is better to use use a different calling convention for system calls there, where struct pt_regs is decoded on-the-fly in a syscall wrapper which then hands processing over to the actual syscall function. This means that only those parameters which are actually needed for a specific syscall are passed on during syscall entry, instead of filling in six CPU registers with random user space content all the time (which may cause serious trouble down the call chain). Those x86-specific patches will be pushed through the x86 tree in the near future. Moreover, rules on how data may be accessed may differ between kernel data and user data. This is another reason why calling sys_xyzzy() is generally a bad idea, and -- at most -- acceptable in arch-specific code. This patchset removes all in-kernel calls to syscall functions in the kernel with the exception of arch/. On top of this, it cleans up the three places where many syscalls are referenced or prototyped, namely kernel/sys_ni.c, include/linux/syscalls.h and include/linux/compat.h" * 'syscalls-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux: (109 commits) bpf: whitelist all syscalls for error injection kernel/sys_ni: remove {sys_,sys_compat} from cond_syscall definitions kernel/sys_ni: sort cond_syscall() entries syscalls/x86: auto-create compat_sys_*() prototypes syscalls: sort syscall prototypes in include/linux/compat.h net: remove compat_sys_*() prototypes from net/compat.h syscalls: sort syscall prototypes in include/linux/syscalls.h kexec: move sys_kexec_load() prototype to syscalls.h x86/sigreturn: use SYSCALL_DEFINE0 x86: fix sys_sigreturn() return type to be long, not unsigned long x86/ioport: add ksys_ioperm() helper; remove in-kernel calls to sys_ioperm() mm: add ksys_readahead() helper; remove in-kernel calls to sys_readahead() mm: add ksys_mmap_pgoff() helper; remove in-kernel calls to sys_mmap_pgoff() mm: add ksys_fadvise64_64() helper; remove in-kernel call to sys_fadvise64_64() fs: add ksys_fallocate() wrapper; remove in-kernel calls to sys_fallocate() fs: add ksys_p{read,write}64() helpers; remove in-kernel calls to syscalls fs: add ksys_truncate() wrapper; remove in-kernel calls to sys_truncate() fs: add ksys_sync_file_range helper(); remove in-kernel calls to syscall kernel: add ksys_setsid() helper; remove in-kernel call to sys_setsid() kernel: add ksys_unshare() helper; remove in-kernel calls to sys_unshare() ...
| * x86/ioport: add ksys_ioperm() helper; remove in-kernel calls to sys_ioperm()Dominik Brodowski2018-04-021-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using this helper allows us to avoid the in-kernel calls to the sys_ioperm() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_ioperm(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: x86@kernel.org Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
| * fs: add ksys_sync() helper; remove in-kernel calls to sys_sync()Dominik Brodowski2018-04-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Using this helper allows us to avoid the in-kernel calls to the sys_sync() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_sync(). This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
* | Merge tag 'arch-removal' of ↵Linus Torvalds2018-04-0219-11368/+0
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pul removal of obsolete architecture ports from Arnd Bergmann: "This removes the entire architecture code for blackfin, cris, frv, m32r, metag, mn10300, score, and tile, including the associated device drivers. I have been working with the (former) maintainers for each one to ensure that my interpretation was right and the code is definitely unused in mainline kernels. Many had fond memories of working on the respective ports to start with and getting them included in upstream, but also saw no point in keeping the port alive without any users. In the end, it seems that while the eight architectures are extremely different, they all suffered the same fate: There was one company in charge of an SoC line, a CPU microarchitecture and a software ecosystem, which was more costly than licensing newer off-the-shelf CPU cores from a third party (typically ARM, MIPS, or RISC-V). It seems that all the SoC product lines are still around, but have not used the custom CPU architectures for several years at this point. In contrast, CPU instruction sets that remain popular and have actively maintained kernel ports tend to all be used across multiple licensees. [ See the new nds32 port merged in the previous commit for the next generation of "one company in charge of an SoC line, a CPU microarchitecture and a software ecosystem" - Linus ] The removal came out of a discussion that is now documented at https://lwn.net/Articles/748074/. Unlike the original plans, I'm not marking any ports as deprecated but remove them all at once after I made sure that they are all unused. Some architectures (notably tile, mn10300, and blackfin) are still being shipped in products with old kernels, but those products will never be updated to newer kernel releases. After this series, we still have a few architectures without mainline gcc support: - unicore32 and hexagon both have very outdated gcc releases, but the maintainers promised to work on providing something newer. At least in case of hexagon, this will only be llvm, not gcc. - openrisc, risc-v and nds32 are still in the process of finishing their support or getting it added to mainline gcc in the first place. They all have patched gcc-7.3 ports that work to some degree, but complete upstream support won't happen before gcc-8.1. Csky posted their first kernel patch set last week, their situation will be similar [ Palmer Dabbelt points out that RISC-V support is in mainline gcc since gcc-7, although gcc-7.3.0 is the recommended minimum - Linus ]" This really says it all: 2498 files changed, 95 insertions(+), 467668 deletions(-) * tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (74 commits) MAINTAINERS: UNICORE32: Change email account staging: iio: remove iio-trig-bfin-timer driver tty: hvc: remove tile driver tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers serial: remove tile uart driver serial: remove m32r_sio driver serial: remove blackfin drivers serial: remove cris/etrax uart drivers usb: Remove Blackfin references in USB support usb: isp1362: remove blackfin arch glue usb: musb: remove blackfin port usb: host: remove tilegx platform glue pwm: remove pwm-bfin driver i2c: remove bfin-twi driver spi: remove blackfin related host drivers watchdog: remove bfin_wdt driver can: remove bfin_can driver mmc: remove bfin_sdh driver input: misc: remove blackfin rotary driver input: keyboard: remove bf54x driver ...
| * | tty: hvc: remove tile driverArnd Bergmann2018-03-262-197/+0
| | | | | | | | | | | | | | | | | | | | | | | | The Tile architecture is obsolete and getting removed from the kernel, this removes the corresponding console driver as well. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | tty: remove bfin_jtag_comm and hvc_bfin_jtag driversArnd Bergmann2018-03-266-481/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | The blackfin architecture is getting removed, so these drivers are not needed any more. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Aaron Wu <aaron.wu@analog.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | serial: remove tile uart driverArnd Bergmann2018-03-263-699/+0
| | | | | | | | | | | | | | | | | | | | | | | | The tile architecture is getting removed, and this driver is useless without it. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | serial: remove m32r_sio driverArnd Bergmann2018-03-264-1233/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | The m32r architecture is getting removed, so we don't need this any more. Acked-by: Nicolas Pitre <nico@fluxnic.net> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | serial: remove blackfin driversArnd Bergmann2018-03-265-2725/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | The blackfin architecture is getting removed, so both the bfin_uart and bfin_sport_uart can be removed as well. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Aaron Wu <aaron.wu@analog.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | serial: remove cris/etrax uart driversArnd Bergmann2018-03-265-5354/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | The cris architecture is getting removed, so we don't need the uart driver any more. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
| * | tty: Remove metag DA TTY and console driverJames Hogan2018-03-053-679/+0
| |/ | | | | | | | | | | | | | | | | | | Now that arch/metag/ has been removed, remove the metag DA TTY and console driver. It is of no value without the architecture code. Signed-off-by: James Hogan <jhogan@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.com> Cc: linux-metag@vger.kernel.org
* | tty: vt: fix up tabstops properlyLinus Torvalds2018-03-251-4/+4
| | | | | | | | | | | | | | | | | | | | Tabs on a console with long lines do not wrap properly, so correctly account for the line length when computing the tab placement location. Reported-by: James Holderness <j4_james@hotmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | serial: imx: fix bogus dev_errphil eichinger2018-02-281-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Only one of the two is really required, not both: * have_rtscts or * have_rtsgpio In imx_rs485_config() this is done correctly, so RS485 is working, just the error message is false. Signed-off-by: Phil Eichinger <phil@zankapfel.net> Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com> Fixes: b8f3bff057b0 ("serial: imx: Support common rs485 binding for RTS polarity" Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | serial: sh-sci: prevent lockup on full TTY buffersUlrich Hecht2018-02-281-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the TTY buffers fill up to the configured maximum, a system lockup occurs: [ 598.820128] INFO: rcu_preempt detected stalls on CPUs/tasks: [ 598.825796] 0-...!: (1 GPs behind) idle=5a6/2/0 softirq=1974/1974 fqs=1 [ 598.832577] (detected by 3, t=62517 jiffies, g=296, c=295, q=126) [ 598.838755] Task dump for CPU 0: [ 598.841977] swapper/0 R running task 0 0 0 0x00000022 [ 598.849023] Call trace: [ 598.851476] __switch_to+0x98/0xb0 [ 598.854870] (null) This can be prevented by doing a dummy read of the RX data register. This issue affects both HSCIF and SCIF ports. Reported for R-Car H3 ES2.0; reproduced and fixed on H3 ES1.1. Probably affects other R-Car platforms as well. Reported-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: stable <stable@vger.kernel.org> Tested-by: Nguyen Viet Dung <dung.nguyen.aj@renesas.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | serial: 8250_pci: Add Brainboxes UC-260 4 port serial deviceNikola Ciprich2018-02-281-0/+11
| | | | | | | | | | | | | | | | | | | | Add PCI ids for two variants of Brainboxes UC-260 quad port PCI serial cards. Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | earlycon: add reg-offset to physical address before mappingGreentime Hu2018-02-281-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | It will get the wrong virtual address because port->mapbase is not added the correct reg-offset yet. We have to update it before earlycon_map() is called Signed-off-by: Greentime Hu <greentime@andestech.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: stable@vger.kernel.org Fixes: 088da2a17619 ("of: earlycon: Initialize port fields from DT properties") Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | serial: core: mark port as initialized in autoconfigSebastian Andrzej Siewior2018-02-281-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a followup on 44117a1d1732 ("serial: core: mark port as initialized after successful IRQ change"). Nikola has been using autoconfig via setserial and reported a crash similar to what I fixed in the earlier mentioned commit. Here I do the same fixup for the autoconfig. I wasn't sure that this is the right approach. Nikola confirmed that it fixes his crash. Fixes: b3b576461864 ("tty: serial_core: convert uart_open to use tty_port_open") Link: http://lkml.kernel.org/r/20180131072000.GD1853@localhost.localdomain Reported-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Tested-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Acked-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | serial: 8250_pci: Don't fail on multiport card classAndy Shevchenko2018-02-281-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Do not fail on multiport cards in serial_pci_is_class_communication(). It restores behaviour for SUNIX multiport cards, that enumerated by class and have a custom board data. Moreover it allows users to reenumerate port-by-port from user space. Fixes: 7d8905d06405 ("serial: 8250_pci: Enable device after we check black list") Reported-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tty/serial: atmel: add new version check for usartJonas Danielsson2018-02-281-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | On our at91sam9260 based board the usart0 and usart1 ports report their versions (ATMEL_US_VERSION) as 0x10302. This version is not included in the current checks in the driver. Signed-off-by: Jonas Danielsson <jonas@orbital-systems.com> Acked-by: Richard Genoud <richard.genoud@gmail.com> Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | tty: make n_tty_read() always abort if hangup is in progressTejun Heo2018-02-282-0/+15
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A tty is hung up by __tty_hangup() setting file->f_op to hung_up_tty_fops, which is skipped on ttys whose write operation isn't tty_write(). This means that, for example, /dev/console whose write op is redirected_tty_write() is never actually marked hung up. Because n_tty_read() uses the hung up status to decide whether to abort the waiting readers, the lack of hung-up marking can lead to the following scenario. 1. A session contains two processes. The leader and its child. The child ignores SIGHUP. 2. The leader exits and starts disassociating from the controlling terminal (/dev/console). 3. __tty_hangup() skips setting f_op to hung_up_tty_fops. 4. SIGHUP is delivered and ignored. 5. tty_ldisc_hangup() is invoked. It wakes up the waits which should clear the read lockers of tty->ldisc_sem. 6. The reader wakes up but because tty_hung_up_p() is false, it doesn't abort and goes back to sleep while read-holding tty->ldisc_sem. 7. The leader progresses to tty_ldisc_lock() in tty_ldisc_hangup() and is now stuck in D sleep indefinitely waiting for tty->ldisc_sem. The following is Alan's explanation on why some ttys aren't hung up. http://lkml.kernel.org/r/20171101170908.6ad08580@alans-desktop 1. It broke the serial consoles because they would hang up and close down the hardware. With tty_port that *should* be fixable properly for any cases remaining. 2. The console layer was (and still is) completely broken and doens't refcount properly. So if you turn on console hangups it breaks (as indeed does freeing consoles and half a dozen other things). As neither can be fixed quickly, this patch works around the problem by introducing a new flag, TTY_HUPPING, which is used solely to tell n_tty_read() that hang-up is in progress for the console and the readers should be aborted regardless of the hung-up status of the device. The following is a sample hung task warning caused by this issue. INFO: task agetty:2662 blocked for more than 120 seconds. Not tainted 4.11.3-dbg-tty-lockup-02478-gfd6c7ee-dirty #28 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. 0 2662 1 0x00000086 Call Trace: __schedule+0x267/0x890 schedule+0x36/0x80 schedule_timeout+0x23c/0x2e0 ldsem_down_write+0xce/0x1f6 tty_ldisc_lock+0x16/0x30 tty_ldisc_hangup+0xb3/0x1b0 __tty_hangup+0x300/0x410 disassociate_ctty+0x6c/0x290 do_exit+0x7ef/0xb00 do_group_exit+0x3f/0xa0 get_signal+0x1b3/0x5d0 do_signal+0x28/0x660 exit_to_usermode_loop+0x46/0x86 do_syscall_64+0x9c/0xb0 entry_SYSCALL64_slow_path+0x25/0x25 The following is the repro. Run "$PROG /dev/console". The parent process hangs in D state. #include <sys/types.h> #include <sys/stat.h> #include <sys/wait.h> #include <sys/ioctl.h> #include <fcntl.h> #include <unistd.h> #include <stdio.h> #include <stdlib.h> #include <errno.h> #include <signal.h> #include <time.h> #include <termios.h> int main(int argc, char **argv) { struct sigaction sact = { .sa_handler = SIG_IGN }; struct timespec ts1s = { .tv_sec = 1 }; pid_t pid; int fd; if (argc < 2) { fprintf(stderr, "test-hung-tty /dev/$TTY\n"); return 1; } /* fork a child to ensure that it isn't already the session leader */ pid = fork(); if (pid < 0) { perror("fork"); return 1; } if (pid > 0) { /* top parent, wait for everyone */ while (waitpid(-1, NULL, 0) >= 0) ; if (errno != ECHILD) perror("waitpid"); return 0; } /* new session, start a new session and set the controlling tty */ if (setsid() < 0) { perror("setsid"); return 1; } fd = open(argv[1], O_RDWR); if (fd < 0) { perror("open"); return 1; } if (ioctl(fd, TIOCSCTTY, 1) < 0) { perror("ioctl"); return 1; } /* fork a child, sleep a bit and exit */ pid = fork(); if (pid < 0) { perror("fork"); return 1; } if (pid > 0) { nanosleep(&ts1s, NULL); printf("Session leader exiting\n"); exit(0); } /* * The child ignores SIGHUP and keeps reading from the controlling * tty. Because SIGHUP is ignored, the child doesn't get killed on * parent exit and the bug in n_tty makes the read(2) block the * parent's control terminal hangup attempt. The parent ends up in * D sleep until the child is explicitly killed. */ sigaction(SIGHUP, &sact, NULL); printf("Child reading tty\n"); while (1) { char buf[1024]; if (read(fd, buf, sizeof(buf)) < 0) { perror("read"); return 1; } } return 0; } Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Alan Cox <alan@llwyncelyn.cymru> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* vfs: do bulk POLL* -> EPOLL* replacementLinus Torvalds2018-02-118-29/+29
| | | | | | | | | | | | | | | | | | | | | | | This is the mindless scripted replacement of kernel use of POLL* variables as described by Al, done by this script: for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'` for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done done with de-mangling cleanups yet to come. NOTE! On almost all architectures, the EPOLL* constants have the same values as the POLL* constants do. But they keyword here is "almost". For various bad reasons they aren't the same, and epoll() doesn't actually work quite correctly in some cases due to this on Sparc et al. The next patch from Al will sort out the final differences, and we should be all done. Scripted-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'acpi-part2-4.16-rc1' of ↵Linus Torvalds2018-02-091-10/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more ACPI updates from Rafael Wysocki: "These are mostly fixes and cleanups, a few new quirks, a couple of updates related to the handling of ACPI tables and ACPICA copyrights refreshment. Specifics: - Update the ACPICA kernel code to upstream revision 20180105 including: * Assorted fixes (Jung-uk Kim) * Support for X32 ABI compilation (Anuj Mittal) * Update of ACPICA copyrights to 2018 (Bob Moore) - Prepare for future modifications to avoid executing the _STA control method too early (Hans de Goede) - Make the processor performance control library code ignore _PPC notifications if they cannot be handled and fix up the C1 idle state definition when it is used as a fallback state (Chen Yu, Yazen Ghannam) - Make it possible to use the SPCR table on x86 and to replace the original IORT table with a new one from initrd (Prarit Bhargava, Shunyong Yang) - Add battery-related quirks for Asus UX360UA and UX410UAK and add quirks for table parsing on Dell XPS 9570 and Precision M5530 (Kai Heng Feng) - Address static checker warnings in the CPPC code (Gustavo Silva) - Avoid printing a raw pointer to the kernel log in the smart battery driver (Greg Kroah-Hartman)" * tag 'acpi-part2-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: ACPI: sbshc: remove raw pointer from printk() message ACPI: SPCR: Make SPCR available to x86 ACPI / CPPC: Use 64-bit arithmetic instead of 32-bit ACPI / tables: Add IORT to injectable table list ACPI / bus: Parse tables as term_list for Dell XPS 9570 and Precision M5530 ACPICA: Update version to 20180105 ACPICA: All acpica: Update copyrights to 2018 ACPI / processor: Set default C1 idle state description ACPI / battery: Add quirk for Asus UX360UA and UX410UAK ACPI: processor_perflib: Do not send _PPC change notification if not ready ACPI / scan: Use acpi_bus_get_status() to initialize ACPI_TYPE_DEVICE devs ACPI / bus: Do not call _STA on battery devices with unmet dependencies PCI: acpiphp_ibm: prepare for acpi_get_object_info() no longer returning status ACPI: export acpi_bus_get_status_handle() ACPICA: Add a missing pair of parentheses ACPICA: Prefer ACPI_TO_POINTER() over ACPI_ADD_PTR() ACPICA: Avoid NULL pointer arithmetic ACPICA: Linux: add support for X32 ABI compilation ACPI / video: Use true for boolean value
| * ACPI: SPCR: Make SPCR available to x86Prarit Bhargava2018-02-071-10/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SPCR is currently only enabled or ARM64 and x86 can use SPCR to setup an early console. General fixes include updating Documentation & Kconfig (for x86), updating comments, and changing parse_spcr() to acpi_parse_spcr(), and earlycon_init_is_deferred to earlycon_acpi_spcr_enable to be more descriptive. On x86, many systems have a valid SPCR table but the table version is not 2 so the table version check must be a warning. On ARM64 when the kernel parameter earlycon is used both the early console and console are enabled. On x86, only the earlycon should be enabled by by default. Modify acpi_parse_spcr() to allow options for initializing the early console and console separately. Signed-off-by: Prarit Bhargava <prarit@redhat.com> Acked-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Mark Salter <msalter@redhat.com> Tested-by: Mark Salter <msalter@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | Merge tag 'driver-core-4.16-rc1' of ↵Linus Torvalds2018-02-011-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here is the set of "big" driver core patches for 4.16-rc1. The majority of the work here is in the firmware subsystem, with reworks to try to attempt to make the code easier to handle in the long run, but no functional change. There's also some tree-wide sysfs attribute fixups with lots of acks from the various subsystem maintainers, as well as a handful of other normal fixes and changes. And finally, some license cleanups for the driver core and sysfs code. All have been in linux-next for a while with no reported issues" * tag 'driver-core-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (48 commits) device property: Define type of PROPERTY_ENRTY_*() macros device property: Reuse property_entry_free_data() device property: Move property_entry_free_data() upper firmware: Fix up docs referring to FIRMWARE_IN_KERNEL firmware: Drop FIRMWARE_IN_KERNEL Kconfig option USB: serial: keyspan: Drop firmware Kconfig options sysfs: remove DEBUG defines sysfs: use SPDX identifiers drivers: base: add coredump driver ops sysfs: add attribute specification for /sysfs/devices/.../coredump test_firmware: fix missing unlock on error in config_num_requests_store() test_firmware: make local symbol test_fw_config static sysfs: turn WARN() into pr_warn() firmware: Fix a typo in fallback-mechanisms.rst treewide: Use DEVICE_ATTR_WO treewide: Use DEVICE_ATTR_RO treewide: Use DEVICE_ATTR_RW sysfs.h: Use octal permissions component: add debugfs support bus: simple-pm-bus: convert bool SIMPLE_PM_BUS to tristate ...
| * | treewide: Use DEVICE_ATTR_RWJoe Perches2018-01-091-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Convert DEVICE_ATTR uses to DEVICE_ATTR_RW where possible. Done with perl script: $ git grep -w --name-only DEVICE_ATTR | \ xargs perl -i -e 'local $/; while (<>) { s/\bDEVICE_ATTR\s*\(\s*(\w+)\s*,\s*\(?(\s*S_IRUGO\s*\|\s*S_IWUSR|\s*S_IWUSR\s*\|\s*S_IRUGO\s*|\s*0644\s*)\)?\s*,\s*\1_show\s*,\s*\1_store\s*\)/DEVICE_ATTR_RW(\1)/g; print;}' Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com> Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Acked-by: Zhang Rui <rui.zhang@intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@bitmer.com> Acked-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | Merge tag 'tty-4.16-rc1' of ↵Linus Torvalds2018-02-0132-330/+460
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/staging driver updates from Greg KH: "Here is the big tty/serial driver update for 4.16-rc1. The usual number of various serial driver fixes and updates to try to get them to work with crazy hardware configurations (seriously, how many different ways are hardware engineers going to come up with to hook up a simple UART?) There is also some serdev bugfixes and updates, as well as a smattering of other small fixes in here. All have been in the linux-next tree for a while, with no reported issues" * tag 'tty-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (65 commits) tty: serial: exar: Relocate sleep wake-up handling tty: fix data race between tty_init_dev and flush of buf serial: imx: fix endless loop during suspend serial: core: mark port as initialized after successful IRQ change serdev: only match serdev devices serdev: do not generate modaliases for controllers serial: mxs-auart: don't use GPIOF_* with gpiod_get_direction serial: 8250_dw: Revert "Improve clock rate setting" MAINTAINERS: Add myself as designated reviewer for 8250_dw gpio: serial: max310x: Support open-drain configuration for GPIOs serdev: Fix serdev_uevent failure on ACPI enumerated serdev-controllers serial: 8250_ingenic: Parse earlycon options serial: 8250_ingenic: Add support for the JZ4770 SoC serial: core: Make uart_parse_options take const char* argument serial: 8250_of: fix return code when probe function fails to get reset serial: imx: Only wakeup via RTSDEN bit if the system has RTS/CTS serial: 8250_uniphier: fix error return code in uniphier_uart_probe() tty: n_gsm: Allow ADM response in addition to UA for control dlci tty: omap-serial: Fix initial on-boot RTS GPIO level tty: serial: jsm: Add one check against NULL pointer dereference ...
| * | tty: serial: exar: Relocate sleep wake-up handlingAaron Sierra2018-01-252-30/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Exar sleep wake-up handling has been done on a per-channel basis by virtue of INT0 being accessible from each channel's address space. I believe this was initially done out of necessity, but now that Exar devices have their own driver, we can do things more efficiently by registering a dedicated INT0 handler at the PCI device level. I see this change providing the following benefits: 1. If more than one port is active, eliminates the redundant bus cycles for reading INT0 on every interrupt. 2. This note associated with hooking in the per-channel handler in 8250_port.c is resolved: /* Fixme: probably not the best place for this */ Cc: Matt Schulte <matts@commtech-fastcom.com> Signed-off-by: Aaron Sierra <asierra@xes-inc.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: fix data race between tty_init_dev and flush of bufGaurav Kohli2018-01-232-3/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There can be a race, if receive_buf call comes before tty initialization completes in n_tty_open and tty->disc_data may be NULL. CPU0 CPU1 ---- ---- 000|n_tty_receive_buf_common() n_tty_open() -001|n_tty_receive_buf2() tty_ldisc_open.isra.3() -002|tty_ldisc_receive_buf(inline) tty_ldisc_setup() Using ldisc semaphore lock in tty_init_dev till disc_data initializes completely. Signed-off-by: Gaurav Kohli <gkohli@codeaurora.org> Reviewed-by: Alan Cox <alan@linux.intel.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: imx: fix endless loop during suspendMartin Kaiser2018-01-221-17/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before we go into suspend mode, we enable the imx uart's interrupt for the awake bit in the UART Status Register 1. If, for some reason, the awake bit is already set before we enter suspend mode, we get an interrupt immediately when we enable interrupts for awake. The uart's clk_ipg is disabled at this point (unless there's an ongoing transfer). We end up in the interrupt handler, which usually tries to clear the awake bit. This doesn't work with the clock disabled. Therefore, we keep getting interrupts forever, resulting in an endless loop. Clear the awake bit before setting the awaken bit to signal that we want an imx interrupt when the awake bit will be set. This ensures that we're not woken up by events that happened before we started going into suspend mode. Change the clock handling so that suspend prepares and enables the clock and suspend_noirq disables it. Revert these operations in resume_noirq and resume. With these preparations in place, we can now modify awake and awaken in the suspend function when the actual imx interrupt is disabled and the required clk_ipg is active. Update the thaw and freeze functions to use the new clock handling since we share the suspend_noirq function between suspend and hibernate. Signed-off-by: Martin Kaiser <martin@kaiser.cx> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: core: mark port as initialized after successful IRQ changeSebastian Andrzej Siewior2018-01-221-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | setserial changes the IRQ via uart_set_info(). It invokes uart_shutdown() which free the current used IRQ and clear TTY_PORT_INITIALIZED. It will then update the IRQ number and invoke uart_startup() before returning to the caller leaving TTY_PORT_INITIALIZED cleared. The next open will crash with | list_add double add: new=ffffffff839fcc98, prev=ffffffff839fcc98, next=ffffffff839fcc98. since the close from the IOCTL won't free the IRQ (and clean the list) due to the TTY_PORT_INITIALIZED check in uart_shutdown(). There is same pattern in uart_do_autoconfig() and I *think* it also needs to set TTY_PORT_INITIALIZED there. Is there a reason why uart_startup() does not set the flag by itself after the IRQ has been acquired (since it is cleared in uart_shutdown)? Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serdev: only match serdev devicesJohan Hovold2018-01-221-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Only serdev devices (a.k.a. clients or slaves) are bound to drivers so bail out early from match() in case the device is not a serdev device (i.e. if it's a serdev controller). Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serdev: do not generate modaliases for controllersJohan Hovold2018-01-221-38/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Serdev controllers are not bound to any drivers and it therefore makes no sense to generate modaliases for them. This has already been fixed separately for ACPI controllers for which uevent errors were also being logged during probe due to the missing ACPI companions (from which ACPI modaliases are generated). This patch moves the modalias handling from the bus type to the client device type. Specifically, this means that only serdev devices (a.k.a. clients or slaves) will have have MODALIAS fields in their uevent environments and corresponding modalias sysfs attributes. Also add the missing static keyword for the modalias device attribute when moving the definition. Reported-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Johan Hovold <johan@kernel.org> Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: mxs-auart: don't use GPIOF_* with gpiod_get_directionWolfram Sang2018-01-221-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The documentation was wrong, gpiod_get_direction() returns 0/1 instead of the GPIOF_* flags. The docs were fixed with commit 94fc73094abe47 ("gpio: correct docs about return value of gpiod_get_direction"). Now, fix this user (until a better, system-wide solution is in place). This also means we can drop the deprecated use of 'linux/gpio.h'. Yay! Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250_dw: Revert "Improve clock rate setting"Andy Shevchenko2018-01-221-18/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The commit de9e33bdfa22 ("serial: 8250_dw: Improve clock rate setting") obviously tries to cure symptoms, and not a root cause. The root cause is the non-flexible rate calculation inside the corresponding clock driver. What we need is to provide maximum UART divisor value to the clock driver to allow it do the job transparently to the caller. Since from the initial commit message I have got no clue which clock driver actually needs to be amended, I leave this exercise to the people who know better the case. Moreover, it seems [1] the fix introduced a regression. And possible even one more [2]. Taking above, revert the commit de9e33bdfa22 for now. [1]: https://www.spinics.net/lists/linux-serial/msg28872.html [2]: https://github.com/Dunedan/mbp-2016-linux/issues/29#issuecomment-357583782 Fixes: de9e33bdfa22 ("serial: 8250_dw: Improve clock rate setting") Cc: stable <stable@vger.kernel.org> # 4.15 Cc: Ed Blake <ed.blake@sondrel.com> Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com> Cc: Lukas Wunner <lukas@wunner.de> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | gpio: serial: max310x: Support open-drain configuration for GPIOsJan Kundrát2018-01-091-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The push-pull vs. open-drain are the only supported output modes. The inputs are always unconditionally equipped with weak pull-downs. That's the only mode, so there's probably no point in exporting that. I wonder if it's worthwhile to provide a custom dbg_show method to indicate the current status of the outputs, though. This patch and [1] for i2c-gpio together make it possible to bit-bang an I2C bus over GPIOs of an UART which is connected via SPI :). Yes, this is crazy, but it's fast enough (while on a 26Mhz SPI HW bus with a dual-core 1.6GHz CPU) to drive an I2C bus at 200kHz, according to my scope. [1] https://patchwork.ozlabs.org/patch/852591/ Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serdev: Fix serdev_uevent failure on ACPI enumerated serdev-controllersHans de Goede2018-01-091-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ACPI enumerated serdev-controllers do not have an ACPI companion, the ACPI companion belongs to the serdev-device child of the serdev-controller, not to the controller itself. This was causing serdev_uevent to always return -ENODEV when called on a serdev-controller leading to errors like these: kernel: serial serial0: uevent: failed to send synthetic uevent being logged. This commit modifies serdev_uevent to directly return 0 when called on an ACPI enumerated serdev-controller fixing this. Note: I do not think that setting a modalias on a devicetree enumerated serdev-controller makes sense either. So perhaps the !dev->of_node part of the check can be dropped too, but I'm not entirely sure that doing this on devicetree too is correct. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250_ingenic: Parse earlycon optionsPaul Cercueil2018-01-091-2/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the devicetree, it is possible to specify the baudrate, parity, bits, flow of the early console, by passing a configuration string like this: aliases { serial0 = &uart0; }; chosen { stdout-path = "serial0:57600n8"; }; This, for instance, will configure the early console for a baudrate of 57600 bps, no parity, and 8 bits per baud. This patches implements parsing of this configuration string in the 8250_ingenic driver, which previously just ignored it. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250_ingenic: Add support for the JZ4770 SoCPaul Cercueil2018-01-091-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | The JZ4770 SoC's UART is no different from the other JZ SoCs, so this commit simply adds the ingenic,jz4770-uart compatible string. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: core: Make uart_parse_options take const char* argumentPaul Cercueil2018-01-091-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | The pointed string is never modified from within uart_parse_options, so it should be marked as const in the function prototype. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250_of: fix return code when probe function fails to get resetMasahiro Yamada2018-01-091-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The error pointer from devm_reset_control_get_optional_shared() is not propagated. One of the most common problem scenarios is it returns -EPROBE_DEFER when the reset controller has not probed yet. In this case, the probe of the reset consumer should be deferred. Fixes: e2860e1f62f2 ("serial: 8250_of: Add reset support") Cc: stable@vger.kernel.org # v4.13+ Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: imx: Only wakeup via RTSDEN bit if the system has RTS/CTSFabio Estevam2018-01-091-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The wakeup mechanism via RTSDEN bit relies on the system using the RTS/CTS lines, so only allow such wakeup method when the system actually has RTS/CTS support. Fixes: bc85734b126f ("serial: imx: allow waking up on RTSD") Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Reviewed-by: Martin Kaiser <martin@kaiser.cx> Acked-by: Fugang Duan <fugang.duan@nxp.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: 8250_uniphier: fix error return code in uniphier_uart_probe()Wei Yongjun2018-01-091-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix to return a negative error code from the port register error handling case instead of 0, as done elsewhere in this function. Fixes: 39be40ce066d ("serial: 8250_uniphier: fix serial port index in private data") Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Acked-by: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: n_gsm: Allow ADM response in addition to UA for control dlciTony Lindgren2018-01-091-3/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some devices have the control dlci stay in ADM mode instead of the UA mode. This can seen at least on droid 4 when trying to open the ts 27.010 mux port. Enabling n_gsm debug mode shows the control dlci always respond with DM to SABM instead of UA: # modprobe n_gsm debug=0xff # ldattach -d GSM0710 /dev/ttyS0 & gsmld_output: 00000000: f9 03 3f 01 1c f9 --> 0) C: SABM(P) gsmld_receive: 00000000: f9 03 1f 01 36 f9 <-- 0) C: DM(P) ... $ minicom -D /dev/gsmtty1 minicom: cannot open /dev/gsmtty1: No error information $ strace minicom -D /dev/gsmtty1 ... open("/dev/gsmtty1", O_RDWR|O_NOCTTY|O_NONBLOCK|O_LARGEFILE) = -1 EL2HLT Note that this is different issue from other n_gsm -EL2HLT issues such as timeouts when the control dlci does not respond at all. The ADM mode seems to be a quite common according to "RF Wireless World" article "GSM Issue-UE sends SABM and gets a DM response instead of UA response": This issue is most commonly observed in GSM networks where in UE sends SABM and expects network to send UA response but it ends up receiving DM response from the network. SABM stands for Set asynchronous balanced mode, UA stands for Unnumbered Acknowledge and DA stands for Disconnected Mode. An RLP entity can be in one of two modes: - Asynchronous Balanced Mode (ABM) - Asynchronous Disconnected Mode (ADM) Currently Linux kernel closes the control dlci after several retries in gsm_dlci_t1() on DM. This causes n_gsm /dev/gsmtty ports to produce error code -EL2HLT when trying to open them as the closing of control dlci has already set gsm->dead. Let's fix the issue by allowing control dlci stay in ADM mode after the retries so the /dev/gsmtty ports can be opened and used. It seems that it might take several attempts to get any response from the control dlci, so it's best to allow ADM mode only after the SABM retries are done. Note that for droid 4 additional patches are needed to mux the ttyS0 pins and to toggle RTS gpio_149 to wake up the mdm6600 modem are also needed to use n_gsm. And the mdm6600 modem needs to be powered on. Cc: linux-serial@vger.kernel.org Cc: Alan Cox <alan@llwyncelyn.cymru> Cc: Jiri Prchal <jiri.prchal@aksignal.cz> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Marcel Partap <mpartap@gmx.net> Cc: Michael Scott <michael.scott@linaro.org> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Russ Gorby <russ.gorby@intel.com> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Sebastian Reichel <sre@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: omap-serial: Fix initial on-boot RTS GPIO levelRafael Gago2018-01-091-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | The rs485 flag "SER_RS485_RTS_AFTER_SEND" was wrongly read from the GPIO flags. This caused the RTS pin to be high during boot. Signed-off-by: Rafael Gago Castano <rgc@hms.se> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: serial: jsm: Add one check against NULL pointer dereferenceGuilherme G. Piccoli2018-01-091-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All calls to neo_copy_data_from_uart_to_queue() are safeguarded against NULL dereference of its parameter, except the one that this patch changes. That said, let's play safe and check for NULL in this case too. Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | tty: serial: jsm: Remove unnecessary NULL checksGuilherme G. Piccoli2018-01-092-9/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After inspection made by Markus using Coccinelle software, he observed that we could possibly be triggering a NULL pointer dereference in 2 functions [0]. After discussion in mailing list, it was observed in fact we have two unnecessary checks for NULL pointer, and they were leading to Coccinelle warn. So, instead of reworking the code as proposed by him, we hereby remove the unnecessary checks, and also some unneeded extra lines in the code. These two unnecessary NULL checks were tracked in the call chain as never NULL, so they can be safely removed. No functional changes are intended. [0] https://lkml.org/lkml/2017/11/29/705 Suggested-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | Merge 4.15-rc6 into tty-nextGreg Kroah-Hartman2018-01-021-2/+2
| |\| | | | | | | | | | | | | | | | We want the ldisc fix here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | pty: cancel pty slave port buf's work in tty_releaseSahara2017-12-191-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In case that CONFIG_SLUB_DEBUG is on and pty is used, races between release_one_tty and flush_to_ldisc work threads may happen and lead to use-after-free condition on tty->link->port. Because SLUB_DEBUG is turned on, freed tty->link->port is filled with POISON_FREE value. So far without SLUB_DEBUG, port was filled with zero and flush_to_ldisc could return without a problem by checking if tty is NULL. CPU 0 CPU 1 ----- ----- release_tty pty_write cancel_work_sync(tty) to = tty->link tty_kref_put(tty->link) tty_schedule_flip(to->port) << workqueue >> ... release_one_tty ... pty_cleanup ... kfree(tty->link->port) << workqueue >> flush_to_ldisc tty = READ_ONCE(port->itty) tty is 0x6b6b6b6b6b6b6b6b !!PANIC!! access tty->ldisc Unable to handle kernel paging request at virtual address 6b6b6b6b6b6b6b93 pgd = ffffffc0eb1c3000 [6b6b6b6b6b6b6b93] *pgd=0000000000000000, *pud=0000000000000000 ------------[ cut here ]------------ Kernel BUG at ffffff800851154c [verbose debug info unavailable] Internal error: Oops - BUG: 96000004 [#1] PREEMPT SMP CPU: 3 PID: 265 Comm: kworker/u8:9 Tainted: G W 3.18.31-g0a58eeb #1 Hardware name: Qualcomm Technologies, Inc. MSM 8996pro v1.1 + PMI8996 Carbide (DT) Workqueue: events_unbound flush_to_ldisc task: ffffffc0ed610ec0 ti: ffffffc0ed624000 task.ti: ffffffc0ed624000 PC is at ldsem_down_read_trylock+0x0/0x4c LR is at tty_ldisc_ref+0x24/0x4c pc : [<ffffff800851154c>] lr : [<ffffff800850f6c0>] pstate: 80400145 sp : ffffffc0ed627cd0 x29: ffffffc0ed627cd0 x28: 0000000000000000 x27: ffffff8009e05000 x26: ffffffc0d382cfa0 x25: 0000000000000000 x24: ffffff800a012f08 x23: 0000000000000000 x22: ffffffc0703fbc88 x21: 6b6b6b6b6b6b6b6b x20: 6b6b6b6b6b6b6b93 x19: 0000000000000000 x18: 0000000000000001 x17: 00e80000f80d6f53 x16: 0000000000000001 x15: 0000007f7d826fff x14: 00000000000000a0 x13: 0000000000000000 x12: 0000000000000109 x11: 0000000000000000 x10: 0000000000000000 x9 : ffffffc0ed624000 x8 : ffffffc0ed611580 x7 : 0000000000000000 x6 : ffffff800a42e000 x5 : 00000000000003fc x4 : 0000000003bd1201 x3 : 0000000000000001 x2 : 0000000000000001 x1 : ffffff800851004c x0 : 6b6b6b6b6b6b6b93 Signed-off-by: Sahara <keun-o.park@darkmatter.ae> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: max310x: Reduce RX work starvationJan Kundrát2017-12-191-13/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Prior to this patch, the code would happily trigger TX on some ports before having a chance of reading the RX buffer from the rest of them. When no flow control was used, this led to RX buffer overruns and therefore lost data under certain circumstances. I was able to reproduce this with MAX14830 (that's a quad channel one) and a simple daisy-chain of RX and TX ports on the eval board: - TX0 -> RX1 - TX1 -> RX2 - TX2 -> RX3 - TX3 -> RX0 I was testing this by transferring 2MB of data at 115200 baud via each port. I used a Solidrun Clearfog Base (Armada 388) which was talking to the UART over an SPI bus clocked at 26MHz (the chip's maximum). Without this patch, I would always get a "Possible RX FIFO overrun" in dmesg, and fewer-than-expected amount of bytes received over ttyMAX0. Results on ttyMAX{1,2,3} tended to be correct all the time, even without the previous patches in this series and with PIO SPI transfers ("indirect mode" as the Marvell datasheet calls it), so I assume that heavy congestion is needed in order to reproduce this. A drawback of this patch is that the throughput gets reduced "a bit". Previously, a 115200 baud resulted in about 11.2kBps throughput as reported by a simple `pv`. With this patch, the throughput of four parallel streams is roughly 7kBps each, and 9kBps for three streams. There is no slowdown for one or two parallel streams. Situation is worse if bytes are being read one-by-one (such as if the userspace wants to perform parity/framing/break checking) and therefore without the batched reads. With just this patch and no other modifications on top of 4.14, I was only getting roughly 3.6kBps with four parallel streams. The single-stream performance was the same, and I was seeing about 7.2kBps with two parallel streams. `perf top` said that a substantial amount of time was spent in `finish_task_switch`, `_raw_spin_unlock_irqrestore` and `__timer_delay`. Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | serial: max310x: Use batched reads when reasonably safeJan Kundrát2017-12-191-40/+86
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The hardware has a 128 byte RX FIFO buffer for each independent UART. Previously, the code was always reading that byte-by-byte via independent SPI transactions and the associated overhead. In practice, this led to up to eight bytes over SPI for just one byte in the UART's RX FIFO: - reading the global IRQ register (two bytes, one for command, the other for data) - reading one UART's ISR (again two bytes) - reading the byte count (two bytes yet again) - finally, reading one byte of the FIFO via another two-byte transaction We cannot always use a batched read. If the TTY is set to intercept break conditions or report framing or parity errors, then it is required to check the Line Status Register (LSR) for each byte which is read from the RX FIFO. The documentation does not show a way of doing that in a single SPI transaction; registers 0x00 and 0x04 are separate. In my testing, this is no silver bullet. I was feeding 2MB of random data over four daisy-chaned UARTs of MAX14830, and this is the distribution that I was getting: - R <= 1: 7437322 - R <= 2: 162093 - R <= 4: 4093 - R <= 8: 4196 - R <= 16: 645 - R <= 32: 165 - R <= 64: 58 - R <= 128: 0 For a reference, batching the write operations works much better: - W <= 1: 2664 - W <= 2: 1305 - W <= 4: 627 - W <= 8: 371 - W <= 16: 121 - W <= 32: 68 - W <= 64: 33 - W <= 128: 63139 That's probably because this HW/SW combination (Clearfog Base, Armada 388) is probably "good enough" to react to the chip's IRQ "fast enough" most of the time. Still, I was getting RX overruns every now and then. In future, I plan to improve this by letting the RX FIFO be filled a little more (the chip has support for that and also for a "stale timeout" to prevent additional starvation). Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>