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2020-01-27kdb: do a sanity check on the cpu in kdb_per_cpu()Dan Carpenter
[ Upstream commit b586627e10f57ee3aa8f0cfab0d6f7dc4ae63760 ] The "whichcpu" comes from argv[3]. The cpu_online() macro looks up the cpu in a bitmap of online cpus, but if the value is too high then it could read beyond the end of the bitmap and possibly Oops. Fixes: 5d5314d6795f ("kdb: core for kgdb back end (1 of 2)") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-11-21kdb: print real address of pointers instead of hashed addressesChristophe Leroy
commit 568fb6f42ac6851320adaea25f8f1b94de14e40a upstream. Since commit ad67b74d2469 ("printk: hash addresses printed with %p"), all pointers printed with %p are printed with hashed addresses instead of real addresses in order to avoid leaking addresses in dmesg and syslog. But this applies to kdb too, with is unfortunate: Entering kdb (current=0x(ptrval), pid 329) due to Keyboard Entry kdb> ps 15 sleeping system daemon (state M) processes suppressed, use 'ps A' to see all. Task Addr Pid Parent [*] cpu State Thread Command 0x(ptrval) 329 328 1 0 R 0x(ptrval) *sh 0x(ptrval) 1 0 0 0 S 0x(ptrval) init 0x(ptrval) 3 2 0 0 D 0x(ptrval) rcu_gp 0x(ptrval) 4 2 0 0 D 0x(ptrval) rcu_par_gp 0x(ptrval) 5 2 0 0 D 0x(ptrval) kworker/0:0 0x(ptrval) 6 2 0 0 D 0x(ptrval) kworker/0:0H 0x(ptrval) 7 2 0 0 D 0x(ptrval) kworker/u2:0 0x(ptrval) 8 2 0 0 D 0x(ptrval) mm_percpu_wq 0x(ptrval) 10 2 0 0 D 0x(ptrval) rcu_preempt The whole purpose of kdb is to debug, and for debugging real addresses need to be known. In addition, data displayed by kdb doesn't go into dmesg. This patch replaces all %p by %px in kdb in order to display real addresses. Fixes: ad67b74d2469 ("printk: hash addresses printed with %p") Cc: <stable@vger.kernel.org> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30kdb: make "mdr" command repeatRandy Dunlap
[ Upstream commit 1e0ce03bf142454f38a5fc050bf4fd698d2d36d8 ] The "mdr" command should repeat (continue) when only Enter/Return is pressed, so make it do so. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: kgdb-bugreport@lists.sourceforge.net Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/debug.h> We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/debug.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/stat.h> We are going to split <linux/sched/stat.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/stat.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar
<linux/sched/loadavg.h> We are going to split <linux/sched/loadavg.h> out of <linux/sched.h>, which will have to be picked up from a couple of .c files. Create a trivial placeholder <linux/sched/topology.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-14kdb: remove unused kdb_event handlingPetr Mladek
kdb_event state variable is only set but never checked in the kernel code. http://www.spinics.net/lists/kdb/msg01733.html suggests that this variable affected WARN_CONSOLE_UNLOCKED() in the original implementation. But this check never went upstream. The semantic is unclear and racy. The value is updated after the kdb_printf_lock is acquired and after it is released. It should be symmetric at minimum. The value should be manipulated either inside or outside the locked area. Fortunately, it seems that the original function is gone and we could simply remove the state variable. Link: http://lkml.kernel.org/r/1480412276-16690-2-git-send-email-pmladek@suse.com Signed-off-by: Petr Mladek <pmladek@suse.com> Suggested-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-12-04module: use a structure to encapsulate layout.Rusty Russell
Makes it easier to handle init vs core cleanly, though the change is fairly invasive across random architectures. It simplifies the rbtree code immediately, however, while keeping the core data together in the same cachline (now iff the rbtree code is enabled). Acked-by: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2015-02-19kdb: Provide forward search at more promptDaniel Thompson
Currently kdb allows the output of comamnds to be filtered using the | grep feature. This is useful but does not permit the output emitted shortly after a string match to be examined without wading through the entire unfiltered output of the command. Such a feature is particularly useful to navigate function traces because these traces often have a useful trigger string *before* the point of interest. This patch reuses the existing filtering logic to introduce a simple forward search to kdb that can be triggered from the more prompt. Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2015-02-19kdb: Fix a prompt management bug when using | grepDaniel Thompson
Currently when the "| grep" feature is used to filter the output of a command then the prompt is not displayed for the subsequent command. Likewise any characters typed by the user are also not echoed to the display. This rather disconcerting problem eventually corrects itself when the user presses Enter and the kdb_grepping_flag is cleared as kdb_parse() tries to make sense of whatever they typed. This patch resolves the problem by moving the clearing of this flag from the middle of command processing to the beginning. Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2015-02-19kdb: Remove stack dump when entering kgdb due to NMIDaniel Thompson
Issuing a stack dump feels ergonomically wrong when entering due to NMI. Entering due to NMI is normally a reaction to a user request, either the NMI button on a server or a "magic knock" on a UART. Therefore the backtrace behaviour on entry due to NMI should be like SysRq-g (no stack dump) rather than like oops. Note also that the stack dump does not offer any information that cannot be trivial retrieved using the 'bt' command. Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2015-02-19kdb: Fix off by one error in kdb_cpu()Jason Wessel
There was a follow on replacement patch against the prior "kgdb: Timeout if secondary CPUs ignore the roundup". See: https://lkml.org/lkml/2015/1/7/442 This patch is the delta vs the patch that was committed upstream: * Fix an off-by-one error in kdb_cpu(). * Replace NR_CPUS with CONFIG_NR_CPUS to tell checkpatch that we really want a static limit. * Removed the "KGDB: " prefix from the pr_crit() in debug_core.c (kgdb-next contains a patch which introduced pr_fmt() to this file to the tag will now be applied automatically). Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: <stable@vger.kernel.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2015-02-19kdb: fix incorrect counts in KDB summary command outputJay Lan
The output of KDB 'summary' command should report MemTotal, MemFree and Buffers output in kB. Current codes report in unit of pages. A define of K(x) as is defined in the code, but not used. This patch would apply the define to convert the values to kB. Please include me on Cc on replies. I do not subscribe to linux-kernel. Signed-off-by: Jay Lan <jlan@sgi.com> Cc: <stable@vger.kernel.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2015-01-23Merge tag 'fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module and param fixes from Rusty Russell: "Surprising number of fixes this merge window :( The first two are minor fallout from the param rework which went in this merge window. The next three are a series which fixes a longstanding (but never previously reported and unlikely , so no CC stable) race between kallsyms and freeing the init section. Finally, a minor cleanup as our module refcount will now be -1 during unload" * tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: module: make module_refcount() a signed integer. module: fix race in kallsyms resolution during module load success. module: remove mod arg from module_free, rename module_memfree(). module_arch_freeing_init(): new hook for archs before module->module_init freed. param: fix uninitialized read with CONFIG_DEBUG_LOCK_ALLOC param: initialize store function to NULL if not available.
2015-01-22module: make module_refcount() a signed integer.Rusty Russell
James Bottomley points out that it will be -1 during unload. It's only used for diagnostics, so let's not hide that as it could be a clue as to what's gone wrong. Cc: Jason Wessel <jason.wessel@windriver.com> Acked-and-documention-added-by: James Bottomley <James.Bottomley@HansenPartnership.com> Reviewed-by: Masami Hiramatsu <maasami.hiramatsu.pt@hitachi.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-11-11kgdb: timeout if secondary CPUs ignore the roundupDaniel Thompson
Currently if an active CPU fails to respond to a roundup request the CPU that requested the roundup will become stuck. This needlessly reduces the robustness of the debugger. This patch introduces a timeout allowing the system state to be examined even when the system contains unresponsive processors. It also modifies kdb's cpu command to make it censor attempts to switch to unresponsive processors and to report their state as (D)ead. Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2014-11-11kdb: Allow access to sensitive commands to be restricted by defaultDaniel Thompson
Currently kiosk mode must be explicitly requested by the bootloader or userspace. It is convenient to be able to change the default value in a similar manner to CONFIG_MAGIC_SYSRQ_DEFAULT_MASK. Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2014-11-11kdb: Add enable mask for groups of commandsAnton Vorontsov
Currently all kdb commands are enabled whenever kdb is deployed. This makes it difficult to deploy kdb to help debug certain types of systems. Android phones provide one example; the FIQ debugger found on some Android devices has a deliberately weak set of commands to allow the debugger to enabled very late in the production cycle. Certain kiosk environments offer another interesting case where an engineer might wish to probe the system state using passive inspection commands without providing sufficient power for a passer by to root it. Without any restrictions, obtaining the root rights via KDB is a matter of a few commands, and works everywhere. For example, log in as a normal user: cbou:~$ id uid=1001(cbou) gid=1001(cbou) groups=1001(cbou) Now enter KDB (for example via sysrq): Entering kdb (current=0xffff8800065bc740, pid 920) due to Keyboard Entry kdb> ps 23 sleeping system daemon (state M) processes suppressed, use 'ps A' to see all. Task Addr Pid Parent [*] cpu State Thread Command 0xffff8800065bc740 920 919 1 0 R 0xffff8800065bca20 *bash 0xffff880007078000 1 0 0 0 S 0xffff8800070782e0 init [...snip...] 0xffff8800065be3c0 918 1 0 0 S 0xffff8800065be6a0 getty 0xffff8800065b9c80 919 1 0 0 S 0xffff8800065b9f60 login 0xffff8800065bc740 920 919 1 0 R 0xffff8800065bca20 *bash All we need is the offset of cred pointers. We can look up the offset in the distro's kernel source, but it is unnecessary. We can just start dumping init's task_struct, until we see the process name: kdb> md 0xffff880007078000 0xffff880007078000 0000000000000001 ffff88000703c000 ................ 0xffff880007078010 0040210000000002 0000000000000000 .....!@......... [...snip...] 0xffff8800070782b0 ffff8800073e0580 ffff8800073e0580 ..>.......>..... 0xffff8800070782c0 0000000074696e69 0000000000000000 init............ ^ Here, 'init'. Creds are just above it, so the offset is 0x02b0. Now we set up init's creds for our non-privileged shell: kdb> mm 0xffff8800065bc740+0x02b0 0xffff8800073e0580 0xffff8800065bc9f0 = 0xffff8800073e0580 kdb> mm 0xffff8800065bc740+0x02b8 0xffff8800073e0580 0xffff8800065bc9f8 = 0xffff8800073e0580 And thus gaining the root: kdb> go cbou:~$ id uid=0(root) gid=0(root) groups=0(root) cbou:~$ bash root:~# p.s. No distro enables kdb by default (although, with a nice KDB-over-KMS feature availability, I would expect at least some would enable it), so it's not actually some kind of a major issue. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2014-11-11kdb: Categorize kdb commands (similar to SysRq categorization)Daniel Thompson
This patch introduces several new flags to collect kdb commands into groups (later allowing them to be optionally disabled). This follows similar prior art to enable/disable magic sysrq commands. The commands have been categorized as follows: Always on: go (w/o args), env, set, help, ?, cpu (w/o args), sr, dmesg, disable_nmi, defcmd, summary, grephelp Mem read: md, mdr, mdp, mds, ef, bt (with args), per_cpu Mem write: mm Reg read: rd Reg write: go (with args), rm Inspect: bt (w/o args), btp, bta, btc, btt, ps, pid, lsmod Flow ctrl: bp, bl, bph, bc, be, bd, ss Signal: kill Reboot: reboot All: cpu, kgdb, (and all of the above), nmi_console Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2014-11-11kdb: Remove KDB_REPEAT_NONE flagAnton Vorontsov
Since we now treat KDB_REPEAT_* as flags, there is no need to pass KDB_REPEAT_NONE. It's just the default behaviour when no flags are specified. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2014-11-11kdb: Use KDB_REPEAT_* values as flagsAnton Vorontsov
The actual values of KDB_REPEAT_* enum values and overall logic stayed the same, but we now treat the values as flags. This makes it possible to add other flags and combine them, plus makes the code a lot simpler and shorter. But functionality-wise, there should be no changes. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2014-11-11kdb: Rename kdb_register_repeat() to kdb_register_flags()Anton Vorontsov
We're about to add more options for commands behaviour, so let's give a more generic name to the low-level kdb command registration function. There are just various renames, no functional changes. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2014-11-11kdb: Rename kdb_repeat_t to kdb_cmdflags_t, cmd_repeat to cmd_flagsAnton Vorontsov
We're about to add more options for command behaviour, so let's expand the meaning of kdb_repeat_t. So far we just do various renames, there should be no functional changes. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2014-11-11kdb: Remove currently unused kdbtab_t->cmd_flagsAnton Vorontsov
The struct member is never used in the code, so we can remove it. We will introduce real flags soon by renaming cmd_repeat to cmd_flags. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2014-06-12kdb: Use ktime_get_ts()Thomas Gleixner
do_posix_clock_monotonic_gettime() is a leftover from the initial posix timer implementation which maps to ktime_get_ts(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Jason Wessel <jason.wessel@windriver.com> Link: http://lkml.kernel.org/r/20140611234607.261629142@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-06-04kernel/printk: use symbolic defines for console loglevelsBorislav Petkov
... instead of naked numbers. Stuff in sysrq.c used to set it to 8 which is supposed to mean above default level so set it to DEBUG instead as we're terminating/killing all tasks and we want to be verbose there. Also, correct the check in x86_64_start_kernel which should be >= as we're clearly issuing the string there for all debug levels, not only the magical 10. Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Randy Dunlap <rdunlap@infradead.org> Cc: Joe Perches <joe@perches.com> Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-10-03kdb: Add support for external NMI handler to call KGDB/KDBMike Travis
This patch adds a kgdb_nmicallin() interface that can be used by external NMI handlers to call the KGDB/KDB handler. The primary need for this is for those types of NMI interrupts where all the CPUs have already received the NMI signal. Therefore no send_IPI(NMI) is required, and in fact it will cause a 2nd unhandled NMI to occur. This generates the "Dazed and Confuzed" messages. Since all the CPUs are getting the NMI at roughly the same time, it's not guaranteed that the first CPU that hits the NMI handler will manage to enter KGDB and set the dbg_master_lock before the slaves start entering. The new argument "send_ready" was added for KGDB to signal the NMI handler to release the slave CPUs for entry into KGDB. Signed-off-by: Mike Travis <travis@sgi.com> Acked-by: Jason Wessel <jason.wessel@windriver.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Reviewed-by: Hedi Berriche <hedi@sgi.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Link: http://lkml.kernel.org/r/20131002151417.928886849@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-03-02kdb: Remove unhandled ssb commandVincent
The 'ssb' command can only be handled when we have a disassembler, to check for branches, so remove the 'ssb' command for now. Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2013-03-02kdb: Prevent kernel oops with kdb_defcmdJason Wessel
The kdb_defcmd can only be used to display the available command aliases while using the kernel debug shell. If you try to define a new macro while the kernel debugger is active it will oops. The debug shell macros must use pre-allocated memory set aside at the time kdb_init() is run, and the kdb_defcmd is restricted to only working at the time that the kdb_init sequence is being run, which only occurs if you actually activate the kernel debugger. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2013-03-02kdb: Remove the ll commandJason Wessel
Recently some code inspection was done after fixing a problem with kmalloc used while in the kernel debugger context (which is not legal), and it turned up the fact that kdb ll command will oops the kernel. Given that there have been zero bug reports on the command combined with the fact it will oops the kernel it is clearly not being used. Instead of fixing it, it will be removed. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2013-03-02kdb_main: fix help printJason Wessel
The help command was chopping all the usage instructions such that they were not readable. Example: bta [D|R|S|T|C|Z|E|U|I| Backtrace all processes matching state flag per_cpu <sym> [<bytes>] [<c Display per_cpu variables Where as it should look like: bta [D|R|S|T|C|Z|E|U|I|M|A] Backtrace all processes matching state flag per_cpu <sym> [<bytes>] [<cpu>] Display per_cpu variables All that is needed is to check the how long the cmd_usage is and jump to the next line when appropriate. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2013-03-02kdb: Fix overlap in buffers with strcpyJason Wessel
Maxime reported that strcpy(s->usage, s->usage+1) has no definitive guarantee that it will work on all archs the same way when you have overlapping memory. The fix is simple for the kdb code because we still have the original string memory in the function scope, so we just have to use that as the argument instead. Reported-by: Maxime Villard <rustyBSD@gmx.fr> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2013-03-02kdb: use ARRAY_SIZE where possibleSasha Levin
Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2013-03-02kdb: A fix for kdb command table expansionJohn Blackwood
When locally adding in some additional kdb commands, I stumbled across an issue with the dynamic expansion of the kdb command table. When the number of kdb commands exceeds the size of the statically allocated kdb_base_commands[] array, additional space is allocated in the kdb_register_repeat() routine. The unused portion of the newly allocated array was not being initialized to zero properly and this would result in segfaults when help '?' was executed or when a search for a non-existing command would traverse the command table beyond the end of valid command entries and then attempt to use the non-zeroed area as actual command entries. Signed-off-by: John Blackwood <john.blackwood@ccur.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2013-01-12module: add new state MODULE_STATE_UNFORMED.Rusty Russell
You should never look at such a module, so it's excised from all paths which traverse the modules list. We add the state at the end, to avoid gratuitous ABI break (ksplice). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-10-13Merge tag 'for_linus-3.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb Pull KGDB/KDB fixes and cleanups from Jason Wessel: "Cleanups - Clean up compile warnings in kgdboc.c and x86/kernel/kgdb.c - Add module event hooks for simplified debugging with gdb Fixes - Fix kdb to stop paging with 'q' on bta and dmesg - Fix for data that scrolls off the vga console due to line wrapping when using the kdb pager New - The debug core registers for kernel module events which allows a kernel aware gdb to automatically load symbols and break on entry to a kernel module - Allow kgdboc=kdb to setup kdb on the vga console" * tag 'for_linus-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb: tty/console: fix warnings in drivers/tty/serial/kgdboc.c kdb,vt_console: Fix missed data due to pager overruns kdb: Fix dmesg/bta scroll to quit with 'q' kgdboc: Accept either kbd or kdb to activate the vga + keyboard kdb shell kgdb,x86: fix warning about unused variable mips,kgdb: fix recursive page fault with CONFIG_KPROBES kgdb: Add module event hooks
2012-10-12kdb: Fix dmesg/bta scroll to quit with 'q'Jason Wessel
If you press 'q' the pager should exit instead of printing everything from dmesg which can really bog down a 9600 baud serial link. The same is true for the bta command. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2012-09-26kdb: Implement disable_nmi commandAnton Vorontsov
This command disables NMI-entry. If NMI source has been previously shared with a serial console ("debug port"), this effectively releases the port from KDB exclusive use, and makes the console available for normal use. Of course, NMI can be reenabled, enable_nmi modparam is used for that: echo 1 > /sys/module/kdb/parameters/enable_nmi Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-31kdb: Remove unused KDB_FLAG_ONLY_DO_DUMPJason Wessel
This code cleanup was missed in the original kdb merge, and this code is simply not used at all. The code that was previously used to set the KDB_FLAG_ONLY_DO_DUMP was removed prior to the initial kdb merge. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2012-07-21kdb: Switch to nolock variants of kmsg_dump functionsAnton Vorontsov
The locked variants are prone to deadlocks (suppose we got to the debugger w/ the logbuf lock held), so let's switch to nolock variants. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-21kdb: Revive dmesg commandAnton Vorontsov
The kgdb dmesg command is broken after the printk rework. The old logic in kdb code makes no sense in terms of current printk/logging storage format, and KDB simply hangs forever. This patch revives the command by switching to kmsg_dumper iterator. The code is now much more simpler and shorter. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-22KDB: Fix usability issues relating to the 'enter' key.Andrei Warkentin
This fixes the following problems: 1) Typematic-repeat of 'enter' gives warning message and leaks make/break if KDB exits. Repeats look something like 0x1c 0x1c .... 0x9c 2) Use of 'keypad enter' gives warning message and leaks the ENTER break/make code out if KDB exits. KP ENTER repeats look someting like 0xe0 0x1c 0xe0 0x1c ... 0xe0 0x9c. 3) Lag on the order of seconds between "break" and "make" when expecting the enter "break" code. Seen under virtualized environments such as VMware ESX. The existing special enter handler tries to glob the enter break code, but this fails if the other (KP) enter was used, or if there was a key repeat. It also fails if you mashed some keys along with enter, and you ended up with a non-enter make or non-enter break code coming after the enter make code. So first, we modify the handler to handle these cases. But performing these actions on every enter is annoying since now you can't hold ENTER down to scroll <more>d messages in KDB. Since this special behaviour is only necessary to handle the exiting KDB ('g' + ENTER) without leaking scancodes to the OS. This cleanup needs to get executed anytime the kdb_main loop exits. Tested on QEMU. Set a bp on atkbd.c to verify no scan code was leaked. Cc: Andrei Warkentin <andreiw@vmware.com> [jason.wessel@windriver.com: move cleanup calls to kdb_main.c] Signed-off-by: Andrei Warkentin <andrey.warkentin@gmail.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2012-01-13module: struct module_ref should contains long fieldsEric Dumazet
module_ref contains two "unsigned int" fields. Thats now too small, since some machines can open more than 2^32 files. Check commit 518de9b39e8 (fs: allow for more than 2^31 files) for reference. We can add an aligned(2 * sizeof(unsigned long)) attribute to force alloc_percpu() allocating module_ref areas in single cache lines. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Rusty Russell <rusty@rustcorp.com.au> CC: Tejun Heo <tj@kernel.org> CC: Robin Holt <holt@sgi.com> CC: David Miller <davem@davemloft.net> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2011-08-01kdb: Remove all references to DOING_KGDB2Jason Wessel
The DOING_KGDB2 was originally a state variable for one of the two ways to automatically transition from kdb to kgdb. Purge all these variables and just use one single state for the transition. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2011-08-01kdb: cleanup unused variables missed in the original kdb mergeJason Wessel
The BTARGS and BTSYMARG variables do not have any function in the mainline version of kdb. Reported-by: Tim Bird <tim.bird@am.sony.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2011-03-31Fix common misspellingsLucas De Marchi
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-25kdb: add usage string of 'per_cpu' commandNamhyung Kim
Signed-off-by: Namhyung Kim <namhyung@gmail.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2011-03-25kdb: code cleanup to use macro instead of valueJovi Zhang
It's better to use macro KDB_BASE_CMD_MAX instead of 50 Signed-off-by: Jovi Zhang <bookjovi@gmail.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2010-12-22Merge branch 'master' into for-nextJiri Kosina
Conflicts: MAINTAINERS arch/arm/mach-omap2/pm24xx.c drivers/scsi/bfa/bfa_fcpim.c Needed to update to apply fixes for which the old branch was too outdated.
2010-11-17kdb: fix crash when KDB_BASE_CMD_MAX is exceededJovi Zhang
When the number of dyanmic kdb commands exceeds KDB_BASE_CMD_MAX, the kernel will fault. Signed-off-by: Jovi Zhang <bookjovi@gmail.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>