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* bug.h: Fix up CONFIG_BUG=n implicit function declarations.Paul Mundt2012-06-251-10/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 2603efa31a03 ("bug.h: Fix up powerpc build regression") corrected the powerpc build case and extended the __ASSEMBLY__ guards, but it also got caught in pre-processor hell accidentally matching the else case of CONFIG_BUG resulting in the BUG disabled case tripping up on -Werror=implicit-function-declaration. It's not possible to __ASSEMBLY__ guard the entire file as architecture code needs to get at the BUGFLAG_WARNING definition in the GENERIC_BUG case, but the rest of the CONFIG_BUG=y/n case needs to be guarded. Rather than littering endless __ASSEMBLY__ checks in each of the if/else cases we just move the BUGFLAG definitions up under their own GENERIC_BUG test and then shove everything else under one big __ASSEMBLY__ guard. Build tested on all of x86 CONFIG_BUG=y, CONFIG_BUG=n, powerpc (due to it's dependence on BUGFLAG definitions in assembly code), and sh (due to not bringing in linux/kernel.h to satisfy the taint flag definitions used by the generic bug code). Hopefully that's the end of the corner cases and I can abstain from ever having to touch this infernal header ever again. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Tested-by: Fengguang Wu <wfg@linux.intel.com> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bug.h: Fix up powerpc build regression.Paul Mundt2012-06-181-3/+5
| | | | | | | | | | | | | | | | | | | | | | | The asm-generic/bug.h __ASSEMBLY__ guarding is completely bogus, which tripped up the powerpc build when the kernel.h include was added: In file included from include/asm-generic/bug.h:5:0, from arch/powerpc/include/asm/bug.h:127, from arch/powerpc/kernel/head_64.S:31: include/linux/kernel.h:44:0: warning: "ALIGN" redefined [enabled by default] include/linux/linkage.h:57:0: note: this is the location of the previous definition include/linux/sysinfo.h: Assembler messages: include/linux/sysinfo.h:7: Error: Unrecognized opcode: `struct' include/linux/sysinfo.h:8: Error: Unrecognized opcode: `__kernel_long_t' Moving the __ASSEMBLY__ guard up and stashing the kernel.h include under it fixes this up, as well as covering the case the original fix was attempting to handle. Tested-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bug.h: need linux/kernel.h for TAINT_WARN.Paul Mundt2012-06-111-0/+1
| | | | | | | | | | | | | | | asm-generic/bug.h uses taint flags that are only defined in linux/kernel.h, resulting in build failures on platforms that don't include linux/kernel.h some other way: arch/sh/include/asm/thread_info.h:172:2: error: 'TAINT_WARN' undeclared (first use in this function) Caused by commit edd63a2763bd ("set_restore_sigmask() is never called without SIGPENDING (and never should be)"). Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* consolidate WARN_...ONCE() static variablesJan Beulich2012-03-231-3/+3
| | | | | | | | | | | | | | | | Due to the alignment of following variables, these typically consume more than just the single byte that 'bool' requires, and as there are a few hundred instances, the cache pollution (not so much the waste of memory) sums up. Put these variables into their own section, outside of any half way frequently used memory range. Do the same also to the __warned variable of rcu_lockdep_assert(). (Don't, however, include the ones used by printk_once() and alike, as they can potentially be hot.) Signed-off-by: Jan Beulich <jbeulich@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* treewide: use __printf not __attribute__((format(printf,...)))Joe Perches2011-10-311-5/+6
| | | | | | | | | | | | | | | | | Standardize the style for compiler based printf format verification. Standardized the location of __printf too. Done via script and a little typing. $ grep -rPl --include=*.[ch] -w "__attribute__" * | \ grep -vP "^(tools|scripts|include/linux/compiler-gcc.h)" | \ xargs perl -n -i -e 'local $/; while (<>) { s/\b__attribute__\s*\(\s*\(\s*format\s*\(\s*printf\s*,\s*(.+)\s*,\s*(.+)\s*\)\s*\)\s*\)/__printf($1, $2)/g ; print; }' [akpm@linux-foundation.org: revert arch bits] Signed-off-by: Joe Perches <joe@perches.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bug.h: Move ratelimit warn interfaces to ratelimit.hDavid S. Miller2011-05-261-40/+0
| | | | | | | | | | | | | | | As reported by Ingo Molnar, we still have configuration combinations where use of the WARN_RATELIMIT interfaces break the build because dependencies don't get met. Instead of going down the long road of trying to make it so that ratelimit.h can get included by kernel.h or asm-generic/bug.h, just move the interface into ratelimit.h and make users have to include that. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
* bug.h: Fix build with CONFIG_PRINTK disabled.David S. Miller2011-05-241-0/+21
| | | | | | | | Based upon an email by Joe Perches. Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
* bug.h: Add WARN_RATELIMITJoe Perches2011-05-231-0/+16
| | | | | | | | | | | Add a generic mechanism to ratelimit WARN(foo, fmt, ...) messages using a hidden per call site static struct ratelimit_state. Also add an __WARN_RATELIMIT variant to be able to use a specific struct ratelimit_state. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* WARN_ON_SMP(): Add comment to explain ({0;})Steven Rostedt2011-03-281-0/+7
| | | | | | | | | | | | | | | | | | | The define to use ({0;}) for the !CONFIG_SMP case of WARN_ON_SMP() can be confusing. As the WARN_ON_SMP() needs to be a nop when CONFIG_SMP is not set, including all its parameters must not be evaluated, and that it must work as both a stand alone statement and inside an if condition, we define it to a funky ({0;}). A simple "0" will not work as it causes gcc to give the warning that the statement has no effect. As this strange definition has raised a few eyebrows from some major kernel developers, it is wise to document why we create such a work of art. Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
* WARN_ON_SMP(): Allow use in if() statements on UPSteven Rostedt2011-03-251-1/+27
| | | | | | | | | | | | | | | | | | | | | | | Both WARN_ON() and WARN_ON_SMP() should be able to be used in an if statement. if (WARN_ON_SMP(foo)) { ... } Because WARN_ON_SMP() is defined as a do { } while (0) on UP, it can not be used this way. Convert it to the same form that WARN_ON() is, even when CONFIG_SMP is off. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Darren Hart <dvhart@linux.intel.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <20110317192208.444147791@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* panic: Allow warnings to set different taint flagsBen Hutchings2010-05-191-2/+32
| | | | | | | | | | | | | | | | | WARN() is used in some places to report firmware or hardware bugs that are then worked-around. These bugs do not affect the stability of the kernel and should not set the flag for TAINT_WARN. To allow for this, add WARN_TAINT() and WARN_TAINT_ONCE() macros that take a taint number as argument. Architectures that implement warnings using trap instructions instead of calls to warn_slowpath_*() now implement __WARN_TAINT(taint) instead of __WARN(). Signed-off-by: Ben Hutchings <ben@decadent.org.uk> Acked-by: Helge Deller <deller@gmx.de> Tested-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* WARN_ONCE(): use bool for boolean flagCesar Eduardo Barros2009-12-151-4/+4
| | | | | | | | | | | | | | | | | | | Commit 70867453092297be9afb2249e712a1f960ec0a09 ("printk_once(): use bool for boolean flag") changed printk_once() to use bool instead of int for its guard variable. Do the same change to WARN_ONCE() and WARN_ON_ONCE(), for the same reasons. This resulted in a reduction of 1462 bytes on a x86-64 defconfig: text data bss dec hex filename 8101271 1207116 992764 10301151 9d2edf vmlinux.before 8100553 1207148 991988 10299689 9d2929 vmlinux.after Signed-off-by: Cesar Eduardo Barros <cesarb@cesarb.net> Cc: Roland Dreier <rolandd@cisco.com> Cc: Daniel Walker <dwalker@fifo99.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Eliminate thousands of warnings with gcc 3.2 buildAndi Kleen2009-05-061-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When building with gcc 3.2 I get thousands of warnings such as include/linux/gfp.h: In function `allocflags_to_migratetype': include/linux/gfp.h:105: warning: null format string due to passing a NULL format string to warn_slowpath() in #define __WARN() warn_slowpath(__FILE__, __LINE__, NULL) Split this case out into a separate call. This also shrinks the kernel slightly: text data bss dec hex filename 4802274 707668 712704 6222646 5ef336 vmlinux text data bss dec hex filename 4799027 703572 712704 6215303 5ed687 vmlinux due to removeing one argument from the commonly-called __WARN(). [akpm@linux-foundation.org: reduce scope of `empty'] Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* The default CONFIG_BUG=n version of BUG() should have an empty do...whileDavid Howells2009-04-151-1/+1
| | | | | | | | The default CONFIG_BUG=n version of BUG() should incorporate an empty a do...while statement to avoid compilation weirdness. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* documentation: when to BUG(), and when to not BUG()David Brownell2009-01-061-0/+17
| | | | | | | | | | | | | | | | | Provide some basic advice about when to use BUG()/BUG_ON(): never, unless there's really no better option. This matches my understanding of the standard policy ... which seems not to be written down so far, outside of LKML messages that I haven't bookmarked. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Hans Verkuil <hverkuil@xs4all.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'core-for-linus' of ↵Linus Torvalds2008-12-301-4/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (63 commits) stacktrace: provide save_stack_trace_tsk() weak alias rcu: provide RCU options on non-preempt architectures too printk: fix discarding message when recursion_bug futex: clean up futex_(un)lock_pi fault handling "Tree RCU": scalable classic RCU implementation futex: rename field in futex_q to clarify single waiter semantics x86/swiotlb: add default swiotlb_arch_range_needs_mapping x86/swiotlb: add default phys<->bus conversion x86: unify pci iommu setup and allow swiotlb to compile for 32 bit x86: add swiotlb allocation functions swiotlb: consolidate swiotlb info message printing swiotlb: support bouncing of HighMem pages swiotlb: factor out copy to/from device swiotlb: add arch hook to force mapping swiotlb: allow architectures to override phys<->bus<->phys conversions swiotlb: add comment where we handle the overflow of a dma mask on 32 bit rcu: fix rcutorture behavior during reboot resources: skip sanity check of busy resources swiotlb: move some definitions to header swiotlb: allow architectures to override swiotlb pool allocation ... Fix up trivial conflicts in arch/x86/kernel/Makefile arch/x86/mm/init_32.c include/linux/hardirq.h as per Ingo's suggestions.
| * debug warnings: eliminate warn_on_slowpath()Ingo Molnar2008-11-281-4/+3
| | | | | | | | | | | | | | | | | | Impact: cleanup, eliminate code now that warn_on_slowpath() uses warn_slowpath(...,NULL), we can eliminate warn_on_slowpath() altogether and use warn_slowpath(). Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | allow bug table entries to use relative pointers (and use it on x86-64)Jan Beulich2008-12-161-0/+8
|/ | | | | | | | | | Impact: reduce bug table size This allows reducing the bug table size by half. Perhaps there are other 64-bit architectures that could also make use of this. Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* fix WARN() for PPCArjan van de Ven2008-10-201-1/+1
| | | | | | | | | powerpc doesn't use the generic WARN_ON infrastructure. The newly introduced WARN() as a result didn't print the message, this patch adds the printk for this specific case. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* include: replace __FUNCTION__ with __func__Harvey Harrison2008-10-161-1/+1
| | | | | | | | __FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* warn: Turn the netdev timeout WARN_ON() into a WARN()Arjan van de Ven2008-09-161-0/+10
| | | | | | | | | | | this patch turns the netdev timeout WARN_ON_ONCE() into a WARN_ONCE(), so that the device and driver names are inside the warning message. This helps automated tools like kerneloops.org to collect the data and do statistics, as well as making it more likely that humans cut-n-paste the important message as part of a bugreport. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* printk ratelimiting rewriteDave Young2008-07-251-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | All ratelimit user use same jiffies and burst params, so some messages (callbacks) will be lost. For example: a call printk_ratelimit(5 * HZ, 1) b call printk_ratelimit(5 * HZ, 1) before the 5*HZ timeout of a, then b will will be supressed. - rewrite __ratelimit, and use a ratelimit_state as parameter. Thanks for hints from andrew. - Add WARN_ON_RATELIMIT, update rcupreempt.h - remove __printk_ratelimit - use __ratelimit in net_ratelimit Signed-off-by: Dave Young <hidave.darkstar@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Cc: Dave Young <hidave.darkstar@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Add a WARN() macro; this is WARN_ON() + printk argumentsArjan van de Ven2008-07-251-0/+22
| | | | | | | | | | | | | Add a WARN() macro that acts like WARN_ON(), with the added feature that it takes a printk like argument that is printed as part of the warning message. [akpm@linux-foundation.org: fix printk arguments] [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Greg KH <greg@kroah.com> Cc: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* debug: move WARN_ON() out of lineArjan van de Ven2008-01-301-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | A quick grep shows that there are currently 1145 instances of WARN_ON in the kernel. Currently, WARN_ON is pretty much entirely inlined, which makes it hard to enhance it without growing the size of the kernel (and getting Andrew unhappy). This patch build on top of Olof's patch that introduces __WARN, and places the slowpath out of line. It also uses Ingo's suggestion to not use __FUNCTION__ but to use kallsyms to do the lookup; this saves a ton of extra space since gcc doesn't need to store the function string twice now: 3936367 833603 624736 5394706 525112 vmlinux.before 3917508 833603 624736 5375847 520767 vmlinux-slowpath 15Kb savings... Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> CC: Andrew Morton <akpm@linux-foundation.org> CC: Olof Johansson <olof@lixom.net> Acked-by: Matt Meckall <mpm@selenic.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* debug: introduce __WARN()Olof Johansson2008-01-301-6/+11
| | | | | | | | | | | Introduce __WARN() in the generic case, so the generic WARN_ON() can use arch-specific code for when the condition is true. Signed-off-by: Olof Johansson <olof@lixom.net> Cc: <linux-arch@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* Fix WARN_ON() on bitfield opsLinus Torvalds2007-07-311-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | Alexey Dobriyan noticed that the new WARN_ON() semantics that were introduced by commit 684f978347deb42d180373ac4c427f82ef963171 (to also return the value to be warned on) didn't compile when given a bitfield, because the typeof doesn't work for bitfields. So instead of the typeof trick, use an "int" variable together with a "!!(x)" expression, as suggested by Al Viro. To make matters more interesting, Paul Mackerras points out that that is sub-optimal on Power, but the old asm-coded comparison seems to be buggy anyway on 32-bit Power if the conditional was 64-bit, so I think there are more problems there. Regardless, the new WARN_ON() semantics may have been a bad idea. But this at least avoids the more serious complications. Cc: Alexey Dobriyan <adobriyan@sw.ru> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Al Viro <viro@ftp.linux.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Cc: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Fix sparse false positives re BUG_ON(ptr)Alexey Dobriyan2007-07-171-1/+1
| | | | | | | | | | | | | | | | | | sparse now warns if one compares pointers with integers. However, there are false positives, like: fs/filesystems.c:72:2: warning: Using plain integer as NULL pointer Every time BUG_ON(ptr) is used, ptr is checked against integer zero. Avoid that and save ~70 false positives from allyesconfig run. mentioned by Al. Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Josh Triplett <josh@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Don't call a warnign a bug. It's a warning.Linus Torvalds2007-05-241-1/+1
| | | | | | | Change the default printout message for WARN_ON() to say what it is, not something else. I'm tired of having people get all aflutter about a warning. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] change WARN_ON back to "BUG: at ..."Ingo Molnar2006-12-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | WARN_ON() ever triggering is a kernel bug. Do not try to paper over this fact by suggesting to the user that this is 'only' a warning, as the following recent commit does: commit 30e25b71e725b150585e17888b130e3324f8cf7c Author: Jeremy Fitzhardinge <jeremy@goop.org> Date: Fri Dec 8 02:36:24 2006 -0800 [PATCH] Fix generic WARN_ON message A warning is a warning, not a BUG. ( it might make sense to rename BUG() to CRASH() and BUG_ON() to CRASH_ON(), but that does not change the fact that WARN_ON() signals a kernel bug. ) i and others objected to this change during lkml review: http://marc.theaimsgroup.com/?l=linux-kernel&m=116115160710533&w=2 still the change slipped upstream - grumble :) Also, use the standard "BUG: " format to make it easier to grep logs and to make it easier to google for kernel bugs. Signed-off-by: Ingo Molnar <mingo@elte.hu> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Fix generic WARN_ON messageJeremy Fitzhardinge2006-12-081-1/+1
| | | | | | | | | A warning is a warning, not a BUG. Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Generic BUG implementationJeremy Fitzhardinge2006-12-081-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds common handling for kernel BUGs, for use by architectures as they wish. The code is derived from arch/powerpc. The advantages of having common BUG handling are: - consistent BUG reporting across architectures - shared implementation of out-of-line file/line data - implement CONFIG_DEBUG_BUGVERBOSE consistently This means that in inline impact of BUG is just the illegal instruction itself, which is an improvement for i386 and x86-64. A BUG is represented in the instruction stream as an illegal instruction, which has file/line information associated with it. This extra information is stored in the __bug_table section in the ELF file. When the kernel gets an illegal instruction, it first confirms it might possibly be from a BUG (ie, in kernel mode, the right illegal instruction). It then calls report_bug(). This searches __bug_table for a matching instruction pointer, and if found, prints the corresponding file/line information. If report_bug() determines that it wasn't a BUG which caused the trap, it returns BUG_TRAP_TYPE_NONE. Some architectures (powerpc) implement WARN using the same mechanism; if the illegal instruction was the result of a WARN, then report_bug(Q) returns CONFIG_DEBUG_BUGVERBOSE; otherwise it returns BUG_TRAP_TYPE_BUG. lib/bug.c keeps a list of loaded modules which can be searched for __bug_table entries. The architecture must call module_bug_finalize()/module_bug_cleanup() from its corresponding module_finalize/cleanup functions. Unsetting CONFIG_DEBUG_BUGVERBOSE will reduce the kernel size by some amount. At the very least, filename and line information will not be recorded for each but, but architectures may decide to store no extra information per BUG at all. Unfortunately, gcc doesn't have a general way to mark an asm() as noreturn, so architectures will generally have to include an infinite loop (or similar) in the BUG code, so that gcc knows execution won't continue beyond that point. gcc does have a __builtin_trap() operator which may be useful to achieve the same effect, unfortunately it cannot be used to actually implement the BUG itself, because there's no way to get the instruction's address for use in generating the __bug_table entry. [randy.dunlap@oracle.com: Handle BUG=n, GENERIC_BUG=n to prevent build errors] [bunk@stusta.de: include/linux/bug.h must always #include <linux/module.h] Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Andi Kleen <ak@muc.de> Cc: Hugh Dickens <hugh@veritas.com> Cc: Michael Ellerman <michael@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Fix warnings for WARN_ON if CONFIG_BUG is disabledRalf Baechle2006-10-201-1/+4
| | | | | | | | | | | | | | | | | | | In most cases the return value of WARN_ON() is ignored. If the generic definition for the !CONFIG_BUG case is used this will result in a warning: CC kernel/sched.o In file included from include/linux/bio.h:25, from include/linux/blkdev.h:14, from kernel/sched.c:39: include/linux/ioprio.h: In function ‘task_ioprio’: include/linux/ioprio.h:50: warning: statement with no effect kernel/sched.c: In function ‘context_switch’: kernel/sched.c:1834: warning: statement with no effect Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Fix WARN_ON / WARN_ON_ONCE regressionAndrew Morton2006-10-061-8/+8
| | | | | | | | | | | | | | | | | | | | | | | | | Tim and Ananiev report that the recent WARN_ON_ONCE changes cause increased cache misses with the tbench workload. Apparently due to the access to the newly-added static variable. Rearrange the code so that we don't touch that variable unless the warning is going to trigger. Also rework the logic so that the static variable starts out at zero, so we can move it into bss. It would seem logical to mark the static variable as __read_mostly too. But it would be wrong, because that would put it back into the vmlinux image, and the kernel will never read from this variable in normal operation anyway. Unless the compiler or hardware go and do some prefetching on us? For some reason this patch shrinks softirq.o text by 40 bytes. Cc: Tim Chen <tim.c.chen@intel.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "Ananiev, Leonid I" <leonid.i.ananiev@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Let WARN_ON/WARN_ON_ONCE return the conditionHerbert Xu2006-09-291-16/+16
| | | | | | | | | | | | | | | | | | | | | | | | | Letting WARN_ON/WARN_ON_ONCE return the condition means that you could do if (WARN_ON(blah)) { handle_impossible_case } Rather than if (unlikely(blah)) { WARN_ON(1) handle_impossible_case } I checked all the newly added WARN_ON_ONCE users and none of them test the return status so we can still change it. [akpm@osdl.org: warning fix] [akpm@osdl.org: build fix] Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] pi-futex: introduce WARN_ON_SMPIngo Molnar2006-06-271-0/+6
| | | | | | | | Introduce a new WARN_ON variant: WARN_ON_SMP(cond). Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] introduce WARN_ON_ONCE(cond)Ingo Molnar2006-06-251-0/+13
| | | | | | | | | | | Add WARN_ON_ONCE(cond) to print once-per-bootup messages. [rostedt@goodmis.org: improve code generation] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Don't include linux/config.h from anywhere else in include/David Woodhouse2006-04-261-1/+0
| | | | Signed-off-by: David Woodhouse <dwmw2@infradead.org>
* [PATCH] make bug messages more consistentIngo Molnar2006-03-231-2/+2
| | | | | | | | | Consolidate all kernel bug printouts to begin with the "BUG: " string. Makes it easier to find them in large bootup logs. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Exterminate PAGE_BUGMatt Mackall2005-05-011-11/+0
| | | | | | | | Remove PAGE_BUG - repalce it with BUG and BUG_ON. Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] remove all kernel BUGsMatt Mackall2005-05-011-0/+19
| | | | | | | | | This patch eliminates all kernel BUGs, trims about 35k off the typical kernel, and makes the system slightly faster. Signed-off-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+34
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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