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2014-04-03printk: do not compute the size of the message twicePetr Mladek
This is just a tiny optimization. It removes duplicate computation of the message size. Signed-off-by: Petr Mladek <pmladek@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jan Kara <jack@suse.cz> Cc: Michal Hocko <mhocko@suse.cz> Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03printk: use also the last bytes in the ring bufferPetr Mladek
It seems that we have newer used the last byte in the ring buffer. In fact, we have newer used the last 4 bytes because of padding. First problem is in the check for free space. The exact number of free bytes is enough to store the length of data. Second problem is in the check where the ring buffer is rotated. The left side counts the first unused index. It is unused, so it might be the same as the size of the buffer. Note that the first problem has to be fixed together with the second one. Otherwise, the buffer is rotated even when there is enough space on the end of the buffer. Then the beginning of the buffer is rewritten and valid entries get corrupted. Signed-off-by: Petr Mladek <pmladek@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jan Kara <jack@suse.cz> Cc: Michal Hocko <mhocko@suse.cz> Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03printk: add comment about tricky check for text buffer sizePetr Mladek
There is no check for potential "text_len" overflow. It is not needed because only valid level is detected. It took me some time to understand why. It would deserve a comment ;-) Signed-off-by: Petr Mladek <pmladek@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jan Kara <jack@suse.cz> Cc: Michal Hocko <mhocko@suse.cz> Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03printk: remove obsolete check for log level "c"Petr Mladek
The kernel log level "c" was removed in commit 61e99ab8e35a ("printk: remove the now unnecessary "C" annotation for KERN_CONT"). It is no longer detected in printk_get_level(). Hence we do not need to check it in vprintk_emit. Signed-off-by: Petr Mladek <pmladek@suse.cz> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jan Kara <jack@suse.cz> Cc: Michal Hocko <mhocko@suse.cz> Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-02-17printk: fix syslog() overflowing user bufferLinus Torvalds
This is not a buffer overflow in the traditional sense: we don't overflow any *kernel* buffers, but we do mis-count the amount of data we copy back to user space for the SYSLOG_ACTION_READ_ALL case. In particular, if the user buffer is too small to hold everything, and *if* there is a continuation line at just the right place, we can end up giving the user more data than he asked for. The reason is that we first count up the number of bytes all the log records contains, then we walk the records again until we've skipped the records at the beginning that won't fit, and then we walk the rest of the records and copy them to the user space buffer. And in between that "skip the initial records that won't fit" and the "copy the records that *will* fit to user space", we reset the 'prev' variable that contained the record information for the last record not copied. That meant that when we started copying to user space, we now had a different character count than what we had originally calculated in the first record walk-through. The fix is to simply not clear the 'prev' flags value (in both cases where we had the same logic: syslog_print_all and kmsg_dump_get_buffer: the latter is used for pstore-like dumping) Reported-and-tested-by: Debabrata Banerjee <dbanerje@akamai.com> Acked-by: Kay Sievers <kay@vrfy.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23printk: flush conflicting continuation lineArun KS
An earlier newline was missing and current print is from different task. In this scenario flush the continuation line and store this line seperatly. This patch fix the below scenario of timestamp interleaving, [ 28.154370 ] read_word_reg : reg[0x 3], reg[0x 4] data [0x 642] [ 28.155428 ] uart disconnect [ 31.947341 ] dvfs[cpufreq.c<275>]:plug-in cpu<1> done [ 28.155445 ] UART detached : send switch state 201 [ 32.014112 ] read_reg : reg[0x 3] data[0x21] [akpm@linux-foundation.org: simplify and condense the code] Signed-off-by: Arun KS <getarunks@gmail.com> Signed-off-by: Arun KS <arun.ks@broadcom.com> Cc: Joe Perches <joe@perches.com> Cc: Tejun Heo <tj@kernel.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-21kernel/printk/printk.c: use memblock apis for early memory allocationsSantosh Shilimkar
Switch to memblock interfaces for early memory allocator instead of bootmem allocator. No functional change in beahvior than what it is in current code from bootmem users points of view. Archs already converted to NO_BOOTMEM now directly use memblock interfaces instead of bootmem wrappers build on top of memblock. And the archs which still uses bootmem, these new apis just fallback to exiting bootmem APIs. Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Paul Walmsley <paul@pwsan.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Russell King <linux@arm.linux.org.uk> Cc: Tony Lindgren <tony@atomide.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13printk.c: comments should refer to /proc/vmcore instead of /proc/vmcoreinfoDirk Gouders
In one of those comments a typo was fixed, too. Signed-off-by: Dirk Gouders <dirk@gouders.net> Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13kernel/printk/printk.c: enable boot delay for earlyprintkDave Young
boot_delay does not work for earlyprintk because the kernel cmdline parsing is late. Change to use early_param so early kernel messages can also be delayed. Signed-off-by: Dave Young <dyoung@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13kernel/printk/printk.c: convert to pr_foo()Andrew Morton
It was half-and-half. Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Joe Perches <joe@perches.com> Cc: Kees Cook <keescook@chromium.org> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13printk: report console names during cut-overKees Cook
This reports the names of consoles as they're being disabled to help identify which is which during cut-over. Helps answer the question "which boot console actually got activated?" once the regular console is running, mostly when debugging boot console failures. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Joe Perches <joe@perches.com> Cc: Tejun Heo <tj@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-03Merge tag 'tty-3.12-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver patches from Greg KH: "Here's the big tty/serial driver pull request for 3.12-rc1. Lots of n_tty reworks to resolve some very long-standing issues, removing the 3-4 different locks that were taken for every character. This code has been beaten on for a long time in linux-next with no reported regressions. Other than that, a range of serial and tty driver updates and revisions. Full details in the shortlog" * tag 'tty-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (226 commits) hvc_xen: Remove unnecessary __GFP_ZERO from kzalloc serial: imx: initialize the local variable tty: ar933x_uart: add device tree support and binding documentation tty: ar933x_uart: allow to build the driver as a module ARM: dts: msm: Update uartdm compatible strings devicetree: serial: Document msm_serial bindings serial: unify serial bindings into a single dir serial: fsl-imx-uart: Cleanup duplicate device tree binding tty: ar933x_uart: use config_enabled() macro to clean up ifdefs tty: ar933x_uart: remove superfluous assignment of ar933x_uart_driver.nr tty: ar933x_uart: use the clk API to get the uart clock tty: serial: cpm_uart: Adding proper request of GPIO used by cpm_uart driver serial: sirf: fix the amount of serial ports serial: sirf: define macro for some magic numbers of USP serial: icom: move array overflow checks earlier TTY: amiserial, remove unnecessary platform_set_drvdata() serial: st-asc: remove unnecessary platform_set_drvdata() msm_serial: Send more than 1 character on the console w/ UARTDM msm_serial: Add support for non-GSBI UARTDM devices msm_serial: Switch clock consumer strings and simplify code ...
2013-08-06printk: Fix return of braille_register_console()Steven Rostedt
Some of my configs I test with have CONFIG_A11Y_BRAILLE_CONSOLE set. When I started testing against v3.11-rc4 my console went bonkers. Using ktest to bisect the issue, it came down to: commit bbeddf52a "printk: move braille console support into separate braille.[ch] files" Looking into the patch I found the problem. It's with the return of braille_register_console(). As anything other than NULL is considered a failure. But for those of us that have CONFIG_A11Y_BRAILLE_CONSOLE set but do not define a "brl" or "brl=" on the command line, we still may want a console that those with sight can still use. Return NULL (success) if "brl" or "brl=" is not on the console line. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Joe Perches <joe@perches.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-05register_console: prevent adding the same console twiceAndreas Bießmann
This patch guards the console_drivers list to be corrupted. The for_each_console() macro insist on a strictly forward list ended by NULL: con0->next->con1->next->NULL Without this patch it may happen easily to destroy this list for example by adding 'earlyprintk' twice, especially on embedded devices where the early console is often a single static instance. This will result in the following list: con0->next->con0 This in turn will result in an endless loop in console_unlock() later on by printing the first __log_buf line endlessly. Signed-off-by: Andreas Bießmann <andreas@biessmann.de> Cc: Kay Sievers <kay@vrfy.org> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-31printk: rename struct log to struct printk_logJoe Perches
Rename the struct to enable moving portions of printk.c to separate files. The rename changes output of /proc/vmcoreinfo. Signed-off-by: Joe Perches <joe@perches.com> Cc: Samuel Thibault <samuel.thibault@ens-lyon.org> Cc: Ming Lei <ming.lei@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-31printk: use pointer for console_cmdline indexingJoe Perches
Make the code a bit more compact by always using a pointer for the active console_cmdline. Move overly indented code to correct indent level. Signed-off-by: Joe Perches <joe@perches.com> Cc: Samuel Thibault <samuel.thibault@ens-lyon.org> Cc: Ming Lei <ming.lei@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-31printk: move braille console support into separate braille.[ch] filesJoe Perches
Create files with prototypes and static inlines for braille support. Make braille_console functions return 1 on success. Corrected CONFIG_A11Y_BRAILLE_CONSOLE=n _braille_console_setup return value to NULL. Signed-off-by: Joe Perches <joe@perches.com> Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org> Cc: Ming Lei <ming.lei@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-31printk: add console_cmdline.hJoe Perches
Add an include file for the console_cmdline struct so that the braille console driver can be separated. Signed-off-by: Joe Perches <joe@perches.com> Cc: Samuel Thibault <samuel.thibault@ens-lyon.org> Cc: Ming Lei <ming.lei@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-31printk: move to separate directory for easier modificationJoe Perches
Make it easier to break up printk into bite-sized chunks. Remove printk path/filename from comment. Signed-off-by: Joe Perches <joe@perches.com> Cc: Samuel Thibault <samuel.thibault@ens-lyon.org> Cc: Ming Lei <ming.lei@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>