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2011-04-07Merge branch 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6Linus Torvalds5-6/+6
* 'for-linus2' of git://git.profusion.mobi/users/lucas/linux-2.6: Fix common misspellings
2011-04-05kemleak-test: build as module onlyDaniel Baluta1-4/+2
mm/kmemleak-test.c is used to provide an example of how kmemleak tool works. Memory is leaked at module unload-time, so building the test in kernel (Y) makes the leaks impossible and the test useless. Qualify DEBUG_KMEMLEAK_TEST config symbol with "depends on m", to restrict module-only building. Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com> Acked-by: Pekka Enberg <penberg@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-31Fix common misspellingsLucas De Marchi5-6/+6
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-28Merge branch 'for-linus-1' of git://git.infradead.org/mtd-2.6Linus Torvalds3-0/+1408
* 'for-linus-1' of git://git.infradead.org/mtd-2.6: (49 commits) mtd: mtdswap: fix compilation warning mtdswap: kill strict error handling option mtd: nand: enable software BCH ECC in nand simulator mtd: nand: add software BCH ECC support mtd: fix printf format warnings, mostly lack of %zd for size_t, in mtdswap mtd: sm_rtl: check kmalloc return value mtd: cfi: add support for AMIC flashes (e.g. A29L160AT) lib: add shared BCH ECC library mtd: mxc_nand: fix OOB corruption when page size > 2KiB mtd: DaVinci: Removed header file that is not required mtd: pxa3xx_nand: clean the keep configure code mtd: pxa3xx_nand: mtd scan id process could be defined by driver itself mtd: pxa3xx_nand: unify prepare command mtd: pxa3xx_nand: discard wait_for_event,write_cmd,__readid function mtd: pxa3xx_nand: rework irq logic mtd: pxa3xx_nand: make scan procedure more clear mtd: speedtest: fix integer overflow mtd: mxc_nand: fix read past buffer end mtd: omap3: nand: report corrected ecc errors jffs2: remove a trailing white space in commentaries ...
2011-03-26Merge branch 'core-fixes-for-linus' of ↵Linus Torvalds1-1/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: futex: Fix WARN_ON() test for UP WARN_ON_SMP(): Allow use in if() statements on UP x86, dumpstack: Use %pB format specifier for stack trace vsprintf: Introduce %pB format specifier lockdep: Remove unused 'factor' variable from lockdep_stats_show()
2011-03-25Merge branch 'master' of ↵Artem Bityutskiy22-388/+1568
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into for-linus-1 * 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6: (9356 commits) [media] rc: update for bitop name changes fs: simplify iget & friends fs: pull inode->i_lock up out of writeback_single_inode fs: rename inode_lock to inode_hash_lock fs: move i_wb_list out from under inode_lock fs: move i_sb_list out from under inode_lock fs: remove inode_lock from iput_final and prune_icache fs: Lock the inode LRU list separately fs: factor inode disposal fs: protect inode->i_state with inode->i_lock lib, arch: add filter argument to show_mem and fix private implementations SLUB: Write to per cpu data when allocating it slub: Fix debugobjects with lockless fastpath autofs4: Do not potentially dereference NULL pointer returned by fget() in autofs_dev_ioctl_setpipefd() autofs4 - remove autofs4_lock autofs4 - fix d_manage() return on rcu-walk autofs4 - fix autofs4_expire_indirect() traversal autofs4 - fix dentry leak in autofs4_expire_direct() autofs4 - reinstate last used update on access vfs - check non-mountpoint dentry might block in __follow_mount_rcu() ... NOTE! This merge commit was created to fix compilation error. The block tree was merged upstream and removed the 'elv_queue_empty()' function which the new 'mtdswap' driver is using. So a simple merge of the mtd tree with upstream does not compile. And the mtd tree has already be published, so re-basing it is not an option. To fix this unfortunate situation, I had to merge upstream into the mtd-2.6.git tree without committing, put the fixup patch on top of this, and then commit this. The result is that we do not have commits which do not compile. In other words, this merge commit "merges" 3 things: the MTD tree, the upstream tree, and the fixup patch.
2011-03-25lib, arch: add filter argument to show_mem and fix private implementationsDavid Rientjes1-6/+1
Commit ddd588b5dd55 ("oom: suppress nodes that are not allowed from meminfo on oom kill") moved lib/show_mem.o out of lib/lib.a, which resulted in build warnings on all architectures that implement their own versions of show_mem(): lib/lib.a(show_mem.o): In function `show_mem': show_mem.c:(.text+0x1f4): multiple definition of `show_mem' arch/sparc/mm/built-in.o:(.text+0xd70): first defined here The fix is to remove __show_mem() and add its argument to show_mem() in all implementations to prevent this breakage. Architectures that implement their own show_mem() actually don't do anything with the argument yet, but they could be made to filter nodes that aren't allowed in the current context in the future just like the generic implementation. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Reported-by: James Bottomley <James.Bottomley@hansenpartnership.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-24vsprintf: Introduce %pB format specifierNamhyung Kim1-1/+6
The %pB format specifier is for stack backtrace. Its handler sprint_backtrace() does symbol lookup using (address-1) to ensure the address will not point outside of the function. If there is a tail-call to the function marked "noreturn", gcc optimized out the code after the call then causes saved return address points outside of the function (i.e. the start of the next function), so pollutes call trace somewhat. This patch adds the %pB printk mechanism that allows architecture call-trace printout functions to improve backtrace printouts. Signed-off-by: Namhyung Kim <namhyung@gmail.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: linux-arch@vger.kernel.org LKML-Reference: <1300934550-21394-1-git-send-email-namhyung@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-03-24bitops: introduce CONFIG_GENERIC_FIND_BIT_LEAkinobu Mita3-0/+7
This introduces CONFIG_GENERIC_FIND_BIT_LE to tell whether to use generic implementation of find_*_bit_le() in lib/find_next_bit.c or not. For now we select CONFIG_GENERIC_FIND_BIT_LE for all architectures which enable CONFIG_GENERIC_FIND_NEXT_BIT. But m68knommu wants to define own faster find_next_zero_bit_le() and continues using generic find_next_{,zero_}bit(). (CONFIG_GENERIC_FIND_NEXT_BIT and !CONFIG_GENERIC_FIND_BIT_LE) Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Greg Ungerer <gerg@uclinux.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-24asm-generic: change little-endian bitops to take any pointer typesAkinobu Mita1-4/+6
This makes the little-endian bitops take any pointer types by changing the prototypes and adding casts in the preprocessor macros. That would seem to at least make all the filesystem code happier, and they can continue to do just something like #define ext2_set_bit __test_and_set_bit_le (or whatever the exact sequence ends up being). Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Mikael Starvik <starvik@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Matthew Wilcox <willy@debian.org> Cc: Grant Grundler <grundler@parisc-linux.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Hirokazu Takata <takata@linux-m32r.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Zankel <chris@zankel.net> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-24asm-generic: rename generic little-endian bitops functionsAkinobu Mita1-5/+4
As a preparation for providing little-endian bitops for all architectures, This renames generic implementation of little-endian bitops. (remove "generic_" prefix and postfix "_le") s/generic_find_next_le_bit/find_next_bit_le/ s/generic_find_next_zero_le_bit/find_next_zero_bit_le/ s/generic_find_first_zero_le_bit/find_first_zero_bit_le/ s/generic___test_and_set_le_bit/__test_and_set_bit_le/ s/generic___test_and_clear_le_bit/__test_and_clear_bit_le/ s/generic_test_le_bit/test_bit_le/ s/generic___set_le_bit/__set_bit_le/ s/generic___clear_le_bit/__clear_bit_le/ s/generic_test_and_set_le_bit/test_and_set_bit_le/ s/generic_test_and_clear_le_bit/test_and_clear_bit_le/ Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Andreas Schwab <schwab@linux-m68k.org> Cc: Greg Ungerer <gerg@uclinux.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23zlib: slim down zlib_deflate() workspace when possibleJim Keniston2-6/+42
Instead of always creating a huge (268K) deflate_workspace with the maximum compression parameters (windowBits=15, memLevel=8), allow the caller to obtain a smaller workspace by specifying smaller parameter values. For example, when capturing oops and panic reports to a medium with limited capacity, such as NVRAM, compression may be the only way to capture the whole report. In this case, a small workspace (24K works fine) is a win, whether you allocate the workspace when you need it (i.e., during an oops or panic) or at boot time. I've verified that this patch works with all accepted values of windowBits (positive and negative), memLevel, and compression level. Signed-off-by: Jim Keniston <jkenisto@us.ibm.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: David Miller <davem@davemloft.net> Cc: Chris Mason <chris.mason@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23kstrto*: converting strings to integers done (hopefully) rightAlexey Dobriyan5-141/+971
1. simple_strto*() do not contain overflow checks and crufty, libc way to indicate failure. 2. strict_strto*() also do not have overflow checks but the name and comments pretend they do. 3. Both families have only "long long" and "long" variants, but users want strtou8() 4. Both "simple" and "strict" prefixes are wrong: Simple doesn't exactly say what's so simple, strict should not exist because conversion should be strict by default. The solution is to use "k" prefix and add convertors for more types. Enter kstrtoull() kstrtoll() kstrtoul() kstrtol() kstrtouint() kstrtoint() kstrtou64() kstrtos64() kstrtou32() kstrtos32() kstrtou16() kstrtos16() kstrtou8() kstrtos8() Include runtime testsuite (somewhat incomplete) as well. strict_strto*() become deprecated, stubbed to kstrto*() and eventually will be removed altogether. Use kstrto*() in code today! Note: on some archs _kstrtoul() and _kstrtol() are left in tree, even if they'll be unused at runtime. This is temporarily solution, because I don't want to hardcode list of archs where these functions aren't needed. Current solution with sizeof() and __alignof__ at least always works. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23printk: allow setting DEFAULT_MESSAGE_LEVEL via KconfigMandeep Singh Baines1-0/+11
We've been burned by regressions/bugs which we later realized could have been triaged quicker if only we'd paid closer attention to dmesg. To make it easier to audit dmesg, we'd like to make DEFAULT_MESSAGE_LEVEL Kconfig-settable. That way we can set it to KERN_NOTICE and audit any messages <= KERN_WARNING. Signed-off-by: Mandeep Singh Baines <msb@chromium.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Joe Perches <joe@perches.com> Cc: Olof Johansson <olofj@chromium.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>
2011-03-23printk: use %pK for /proc/kallsyms and /proc/modulesKees Cook1-1/+1
In an effort to reduce kernel address leaks that might be used to help target kernel privilege escalation exploits, this patch uses %pK when displaying addresses in /proc/kallsyms, /proc/modules, and /sys/module/*/sections/*. Note that this changes %x to %p, so some legitimately 0 values in /proc/kallsyms would have changed from 00000000 to "(null)". To avoid this, "(null)" is not used when using the "K" format. Anything that was already successfully parsing "(null)" in addition to full hex digits should have no problem with this change. (Thanks to Joe Perches for the suggestion.) Due to the %x to %p, "void *" casts are needed since these addresses are already "unsigned long" everywhere internally, due to their starting life as ELF section offsets. Signed-off-by: Kees Cook <kees.cook@canonical.com> Cc: Eugene Teo <eugene@redhat.com> Cc: Dan Rosenberg <drosenberg@vsecurity.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23vsprintf: neaten %pK kptr_restrict, save a bit of code spaceJoe Perches1-9/+5
If kptr restrictions are on, just set the passed pointer to NULL. $ size lib/vsprintf.o.* text data bss dec hex filename 8247 4 2 8253 203d lib/vsprintf.o.new 8282 4 2 8288 2060 lib/vsprintf.o.old Signed-off-by: Joe Perches <joe@perches.com> Cc: Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23kernel/watchdog.c: allow hardlockup to panic by defaultDon Zickus1-0/+17
When a cpu is considered stuck, instead of limping along and just printing a warning, it is sometimes preferred to just panic, let kdump capture the vmcore and reboot. This gets the machine back into a stable state quickly while saving the info that got it into a stuck state to begin with. Add a Kconfig option to allow users to set the hardlockup to panic by default. Also add in a 'nmi_watchdog=nopanic' to override this. [akpm@linux-foundation.org: fix strncmp length] Signed-off-by: Don Zickus <dzickus@redhat.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-23oom: suppress nodes that are not allowed from meminfo on oom killDavid Rientjes1-2/+7
The oom killer is extremely verbose for machines with a large number of cpus and/or nodes. This verbosity can often be harmful if it causes other important messages to be scrolled from the kernel log and incurs a signicant time delay, specifically for kernels with CONFIG_NODES_SHIFT > 8. This patch causes only memory information to be displayed for nodes that are allowed by current's cpuset when dumping the VM state. Information for all other nodes is irrelevant to the oom condition; we don't care if there's an abundance of memory elsewhere if we can't access it. This only affects the behavior of dumping memory information when an oom is triggered. Other dumps, such as for sysrq+m, still display the unfiltered form when using the existing show_mem() interface. Additionally, the per-cpu pageset statistics are extremely verbose in oom killer output, so it is now suppressed. This removes nodes_weight(current->mems_allowed) * (1 + nr_cpus) lines from the oom killer output. Callers may use __show_mem(SHOW_MEM_FILTER_NODES) to filter disallowed nodes. Signed-off-by: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22Merge branch 'kbuild' of ↵Linus Torvalds1-5/+0
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6 * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6: kbuild: Make DEBUG_SECTION_MISMATCH selectable, but not on by default genksyms: Regenerate lexer and parser genksyms: Track changes to enum constants genksyms: simplify usage of find_symbol() genksyms: Add helpers for building string lists genksyms: Simplify printing of symbol types genksyms: Simplify lexer genksyms: Do not paste the bison header file to lex.c modpost: fix trailing comma KBuild: silence "'scripts/unifdef' is up to date." kbuild: Add extra gcc checks kbuild: reenable section mismatch analysis unifdef: update to upstream version 2.5
2011-03-21kbuild: Make DEBUG_SECTION_MISMATCH selectable, but not on by defaultMichal Marek1-1/+0
CONFIG_DEBUG_SECTION_MISMATCH has also runtime effects due to the -fno-inline-functions-called-once compiler flag, so forcing it on everyone is not a good idea. Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-03-17Merge branch 'config' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bklLinus Torvalds3-153/+0
* 'config' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl: BKL: That's all, folks fs/locks.c: Remove stale FIXME left over from BKL conversion ipx: remove the BKL appletalk: remove the BKL x25: remove the BKL ufs: remove the BKL hpfs: remove the BKL drivers: remove extraneous includes of smp_lock.h tracing: don't trace the BKL adfs: remove the big kernel lock
2011-03-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6Linus Torvalds3-1/+283
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1480 commits) bonding: enable netpoll without checking link status xfrm: Refcount destination entry on xfrm_lookup net: introduce rx_handler results and logic around that bonding: get rid of IFF_SLAVE_INACTIVE netdev->priv_flag bonding: wrap slave state work net: get rid of multiple bond-related netdevice->priv_flags bonding: register slave pointer for rx_handler be2net: Bump up the version number be2net: Copyright notice change. Update to Emulex instead of ServerEngines e1000e: fix kconfig for crc32 dependency netfilter ebtables: fix xt_AUDIT to work with ebtables xen network backend driver bonding: Improve syslog message at device creation time bonding: Call netif_carrier_off after register_netdevice bonding: Incorrect TX queue offset net_sched: fix ip_tos2prio xfrm: fix __xfrm_route_forward() be2net: Fix UDP packet detected status in RX compl Phonet: fix aligned-mode pipe socket buffer header reserve netxen: support for GbE port settings ... Fix up conflicts in drivers/staging/brcm80211/brcmsmac/wl_mac80211.c with the staging updates.
2011-03-17Merge branch 'driver-core-next' of ↵Linus Torvalds1-9/+52
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6 * 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (50 commits) printk: do not mangle valid userspace syslog prefixes efivars: Add Documentation efivars: Expose efivars functionality to external drivers. efivars: Parameterize operations. efivars: Split out variable registration efivars: parameterize efivars efivars: Make efivars bin_attributes dynamic efivars: move efivars globals into struct efivars drivers:misc: ti-st: fix debugging code kref: Fix typo in kref documentation UIO: add PRUSS UIO driver support Fix spelling mistakes in Documentation/zh_CN/SubmittingPatches firmware: Fix unaligned memory accesses in dmi-sysfs firmware: Add documentation for /sys/firmware/dmi firmware: Expose DMI type 15 System Event Log firmware: Break out system_event_log in dmi-sysfs firmware: Basic dmi-sysfs support firmware: Add DMI entry types to the headers Driver core: convert platform_{get,set}_drvdata to static inline functions Translate linux-2.6/Documentation/magic-number.txt into Chinese ...
2011-03-16Merge branch 'core-locking-for-linus' of ↵Linus Torvalds1-6/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: rtmutex: tester: Remove the remaining BKL leftovers lockdep/timers: Explain in detail the locking problems del_timer_sync() may cause rtmutex: Simplify PI algorithm and make highest prio task get lock rwsem: Remove redundant asmregparm annotation rwsem: Move duplicate function prototypes to linux/rwsem.h rwsem: Unify the duplicate rwsem_is_locked() inlines rwsem: Move duplicate init macros and functions to linux/rwsem.h rwsem: Move duplicate struct rwsem declaration to linux/rwsem.h x86: Cleanup rwsem_count_t typedef rwsem: Cleanup includes locking: Remove deprecated lock initializers cred: Replace deprecated spinlock initialization kthread: Replace deprecated spinlock initialization xtensa: Replace deprecated spinlock initialization um: Replace deprecated spinlock initialization sparc: Replace deprecated spinlock initialization mips: Replace deprecated spinlock initialization cris: Replace deprecated spinlock initialization alpha: Replace deprecated spinlock initialization rtmutex-tester: Remove BKL tests
2011-03-16Merge branch 'core-futexes-for-linus' of ↵Linus Torvalds1-20/+115
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-futexes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: arm: Remove bogus comment in futex_atomic_cmpxchg_inatomic() futex: Deobfuscate handle_futex_death() plist: Add priority list test plist: Shrink struct plist_head futex,plist: Remove debug lock assignment from plist_node futex,plist: Pass the real head of the priority list to plist_del() futex: Sanitize futex ops argument types futex: Sanitize cmpxchg_futex_value_locked API futex: Remove redundant pagefault_disable in futex_atomic_cmpxchg_inatomic() futex: Avoid redudant evaluation of task_pid_vnr() futex: Update futex_wait_setup comments about locking
2011-03-11plist: Add priority list testLai Jiangshan1-1/+80
Add test code for checking plist when the kernel is booting. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> LKML-Reference: <4D107986.1010302@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-03-11plist: Shrink struct plist_headLai Jiangshan1-19/+35
struct plist_head is used in struct task_struct as well as struct rtmutex. If we can make it smaller, it will also make these structures smaller as well. The field prio_list in struct plist_head is seldom used and we can get its information from the plist_nodes. Removing this field will decrease the size of plist_head by half. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> LKML-Reference: <4D107982.9090700@cn.fujitsu.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2011-03-11Merge branch 'master' of ↵John W. Linville1-1/+8
git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6 into for-davem
2011-03-11lib: add shared BCH ECC libraryIvan Djelic3-0/+1408
This is a new software BCH encoding/decoding library, similar to the shared Reed-Solomon library. Binary BCH (Bose-Chaudhuri-Hocquenghem) codes are widely used to correct errors in NAND flash devices requiring more than 1-bit ecc correction; they are generally better suited for NAND flash than RS codes because NAND bit errors do not occur in bursts. Latest SLC NAND devices typically require at least 4-bit ecc protection per 512 bytes block. This library provides software encoding/decoding, but may also be used with ASIC/SoC hardware BCH engines to perform error correction. It is being currently used for this purpose on an OMAP3630 board (4bit/8bit HW BCH). It has also been used to decode raw dumps of NAND devices with on-die BCH ecc engines (e.g. Micron 4bit ecc SLC devices). Latest NAND devices (including SLC) can exhibit high error rates (typically a dozen or more bitflips per hour during stress tests); in order to minimize the performance impact of error correction, this library implements recently developed algorithms for fast polynomial root finding (see bch.c header for details) instead of the traditional exhaustive Chien root search; a few performance figures are provided below: Platform: arm926ejs @ 468 MHz, 32 KiB icache, 16 KiB dcache BCH ecc : 4-bit per 512 bytes Encoding average throughput: 250 Mbits/s Error correction time (compared with Chien search): average worst average (Chien) worst (Chien) ---------------------------------------------------------- 1 bit 8.5 µs 11 µs 200 µs 383 µs 2 bit 9.7 µs 12.5 µs 477 µs 728 µs 3 bit 18.1 µs 20.6 µs 758 µs 1010 µs 4 bit 19.5 µs 23 µs 1028 µs 1280 µs In the above figures, "worst" is meant in terms of error pattern, not in terms of cache miss / page faults effects (not taken into account here). The library has been extensively tested on the following platforms: x86, x86_64, arm926ejs, omap3630, qemu-ppc64, qemu-mips. Signed-off-by: Ivan Djelic <ivan.djelic@parrot.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2011-03-08debugobjects: Add hint for better object identificationStanislaw Gruszka1-3/+6
In complex subsystems like mac80211 structures can contain several timers and work structs, so identifying a specific instance from the call trace and object type output of debugobjects can be hard. Allow the subsystems which support debugobjects to provide a hint function. This function returns a pointer to a kernel address (preferrably the objects callback function) which is printed along with the debugobjects type. Add hint methods for timer_list, work_struct and hrtimer. [ tglx: Massaged changelog, made it compile ] Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> LKML-Reference: <20110307085809.GA9334@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-03-05BKL: That's all, folksArnd Bergmann3-146/+0
This removes the implementation of the big kernel lock, at last. A lot of people have worked on this in the past, I so the credit for this patch should be with everyone who participated in the hunt. The names on the Cc list are the people that were the most active in this, according to the recorded git history, in alphabetical order. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Alan Cox <alan@linux.intel.com> Cc: Alessio Igor Bogani <abogani@texware.it> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Hendry <andrew.hendry@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Hans Verkuil <hverkuil@xs4all.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Jan Blunck <jblunck@infradead.org> Cc: John Kacur <jkacur@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matthew Wilcox <matthew@wil.cx> Cc: Oliver Neukum <oliver@neukum.org> Cc: Paul Menage <menage@google.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-04lib-average: Make config option selectableMichael Buesch1-1/+8
Make CONFIG_AVERAGE selectable for out-of-tree users such as compat-wireless. Signed-off-by: Michael Buesch <mb@bu3sch.de> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-03-04Merge branch 'master' of ↵David S. Miller2-3/+5
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: drivers/net/bnx2x/bnx2x.h
2011-03-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds1-1/+1
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (42 commits) MAINTAINERS: Add Andy Gospodarek as co-maintainer. r8169: disable ASPM RxRPC: Fix v1 keys AF_RXRPC: Handle receiving ACKALL packets cnic: Fix lost interrupt on bnx2x cnic: Prevent status block race conditions with hardware net: dcbnl: check correct ops in dcbnl_ieee_set() e1000e: disable broken PHY wakeup for ICH10 LOMs, use MAC wakeup instead igb: fix sparse warning e1000: fix sparse warning netfilter: nf_log: avoid oops in (un)bind with invalid nfproto values dccp: fix oops on Reset after close ipvs: fix dst_lock locking on dest update davinci_emac: Add Carrier Link OK check in Davinci RX Handler bnx2x: update driver version to 1.62.00-6 bnx2x: properly calculate lro_mss bnx2x: perform statistics "action" before state transition. bnx2x: properly configure coefficients for MinBW algorithm (NPAR mode). bnx2x: Fix ethtool -t link test for MF (non-pmf) devices. bnx2x: Fix nvram test for single port devices. ...
2011-03-02tracing: don't trace the BKLArnd Bergmann1-7/+0
No reason to trace it when the last user is gone. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
2011-02-28net: fix nla_policy_len to actually _iterate_ over the policyLars Ellenberg1-1/+1
Currently nla_policy_len always returns n * NLA_HDRLEN: It loops, but does not advance it's iterator. NLA_UNSPEC == 0 does not contain a .len in any policy. Trivially fixed by adding p++. Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-26swiotlb: fix wrong panicFUJITA Tomonori1-2/+4
swiotlb's map_page wrongly calls panic() when it can't find a buffer fit for device's dma mask. It should return an error instead. Devices with an odd dma mask (i.e. under 4G) like b44 network card hit this bug (the system crashes): http://marc.info/?l=linux-kernel&m=129648943830106&w=2 If swiotlb returns an error, b44 driver can use the own bouncing mechanism. Reported-by: Chuck Ebbert <cebbert@redhat.com> Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Tested-by: Arkadiusz Miskiewicz <arekm@maven.pl> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-24kbuild: reenable section mismatch analysisUwe Kleine-König1-4/+0
This was disabled in commit e5f95c8 (kbuild: print only total number of section mismatces found) because there were too many warnings. Now we're down to a reasonable number again, so we start scaring people with the details. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Randy Dunlap <rdunlap@xenotime.net> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Michal Marek <mmarek@suse.cz>
2011-02-20Merge branch 'master' of ↵David S. Miller4-17/+34
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 Conflicts: Documentation/feature-removal-schedule.txt drivers/net/e1000e/netdev.c net/xfrm/xfrm_policy.c
2011-02-18Expand CONFIG_DEBUG_LIST to several other list operationsLinus Torvalds1-13/+26
When list debugging is enabled, we aim to readably show list corruption errors, and the basic list_add/list_del operations end up having extra debugging code in them to do some basic validation of the list entries. However, "list_del_init()" and "list_move[_tail]()" ended up avoiding the debug code due to how they were written. This fixes that. So the _next_ time we have list_move() problems with stale list entries, we'll hopefully have an easier time finding them.. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-16Merge commit 'v2.6.38-rc5' into core/lockingIngo Molnar3-6/+9
Merge reason: pick up upstream fixes. Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-02-08m68knommu: Remove dependencies on nonexistent M68KNOMMUGeert Uytterhoeven1-1/+1
M68KNOMMU is set nowhere. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Greg Ungerer <gerg@uclinux.org>
2011-02-04dynamic_debug: add #include <linux/sched.h>Greg Kroah-Hartman1-0/+1
This fixes a build breakage caused by 8ba6ebf583f12da32036fc0f003ab4043e54692e "Dynamic debug: Add more flags" Cc: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-02-04Dynamic debug: Add more flagsBart Van Assche1-9/+51
Add flags that allow the user to specify via debugfs whether or not the module name, function name, line number and/or thread ID have to be included in the printed message. Signed-off-by: Bart Van Assche <bvanassche@acm.org> Cc: Greg Banks <gnb@fmeh.org> Cc: Konrad Rzeszutek Wilk <konrad@darnok.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2011-01-31Merge branch 'tip/rtmutex' of ↵Thomas Gleixner1-3/+4
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace into core/locking *git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace tip/rtmutex: rtmutex: Simplify PI algorithm and make highest prio task get lock
2011-01-28Export the augmented rbtree helper functionsAndreas Gruenbacher1-0/+3
The augmented rbtree helper functions are not exported to modules right now. (We have started using augmented rbtrees in the upcoming version of drbd.) Signed-off-by: Andreas Gruenbacher <agruen@linbit.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds1-5/+5
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (43 commits) bnx2: Eliminate AER error messages on systems not supporting it cnic: Fix big endian bug xfrm6: Don't forget to propagate peer into ipsec route. tg3: Use new VLAN code bonding: update documentation - alternate configuration. TCP: fix a bug that triggers large number of TCP RST by mistake MAINTAINERS: remove Reinette Chatre as iwlwifi maintainer rt2x00: add device id for windy31 usb device mac80211: fix a crash in ieee80211_beacon_get_tim on change_interface ipv6: Revert 'administrative down' address handling changes. textsearch: doc - fix spelling in lib/textsearch.c. USB NET KL5KUSB101: Fix mem leak in error path of kaweth_download_firmware() pch_gbe: don't use flush_scheduled_work() bnx2: Always set ETH_FLAG_TXVLAN net: clear heap allocation for ethtool_get_regs() ipv6: Always clone offlink routes. dcbnl: make get_app handling symmetric for IEEE and CEE DCBx tcp: fix bug in listening_get_next() inetpeer: Use correct AVL tree base pointer in inet_getpeer(). GRO: fix merging a paged skb after non-paged skbs ...
2011-01-27rwsem: Remove redundant asmregparm annotationThomas Gleixner1-6/+4
Peter Zijlstra pointed out, that the only user of asmregparm (x86) is compiling the kernel already with -mregparm=3. So the annotation of the rwsem functions is redundant. Remove it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: David Howells <dhowells@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: David Miller <davem@davemloft.net> Cc: Chris Zankel <chris@zankel.net> LKML-Reference: <alpine.LFD.2.00.1101262130450.31804@localhost6.localdomain6> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-01-27Merge branch 'master' of ↵David S. Miller1-5/+5
master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
2011-01-26radix_tree: radix_tree_gang_lookup_tag_slot() may never returnToshiyuki Okajima1-3/+4
Executed command: fsstress -d /mnt -n 600 -p 850 crash> bt PID: 7947 TASK: ffff880160546a70 CPU: 0 COMMAND: "fsstress" #0 [ffff8800dfc07d00] machine_kexec at ffffffff81030db9 #1 [ffff8800dfc07d70] crash_kexec at ffffffff810a7952 #2 [ffff8800dfc07e40] oops_end at ffffffff814aa7c8 #3 [ffff8800dfc07e70] die_nmi at ffffffff814aa969 #4 [ffff8800dfc07ea0] do_nmi_callback at ffffffff8102b07b #5 [ffff8800dfc07f10] do_nmi at ffffffff814aa514 #6 [ffff8800dfc07f50] nmi at ffffffff814a9d60 [exception RIP: __lookup_tag+100] RIP: ffffffff812274b4 RSP: ffff88016056b998 RFLAGS: 00000287 RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000006 RDX: 000000000000001d RSI: ffff88016056bb18 RDI: ffff8800c85366e0 RBP: ffff88016056b9c8 R8: ffff88016056b9e8 R9: 0000000000000000 R10: 000000000000000e R11: ffff8800c8536908 R12: 0000000000000010 R13: 0000000000000040 R14: ffffffffffffffc0 R15: ffff8800c85366e0 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 <NMI exception stack> #7 [ffff88016056b998] __lookup_tag at ffffffff812274b4 #8 [ffff88016056b9d0] radix_tree_gang_lookup_tag_slot at ffffffff81227605 #9 [ffff88016056ba20] find_get_pages_tag at ffffffff810fc110 #10 [ffff88016056ba80] pagevec_lookup_tag at ffffffff81105e85 #11 [ffff88016056baa0] write_cache_pages at ffffffff81104c47 #12 [ffff88016056bbd0] generic_writepages at ffffffff81105014 #13 [ffff88016056bbe0] do_writepages at ffffffff81105055 #14 [ffff88016056bbf0] __filemap_fdatawrite_range at ffffffff810fb2cb #15 [ffff88016056bc40] filemap_write_and_wait_range at ffffffff810fb32a #16 [ffff88016056bc70] generic_file_direct_write at ffffffff810fb3dc #17 [ffff88016056bce0] __generic_file_aio_write at ffffffff810fcee5 #18 [ffff88016056bda0] generic_file_aio_write at ffffffff810fd085 #19 [ffff88016056bdf0] do_sync_write at ffffffff8114f9ea #20 [ffff88016056bf00] vfs_write at ffffffff8114fcf8 #21 [ffff88016056bf30] sys_write at ffffffff81150691 #22 [ffff88016056bf80] system_call_fastpath at ffffffff8100c0b2 I think this root cause is the following: radix_tree_range_tag_if_tagged() always tags the root tag with settag if the root tag is set with iftag even if there are no iftag tags in the specified range (Of course, there are some iftag tags outside the specified range). =============================================================================== [[[Detailed description]]] (1) Why cannot radix_tree_gang_lookup_tag_slot() return forever? __lookup_tag(): - Return with 0. - Return with the index which is not bigger than the old one as the input parameter. Therefore the following "while" repeats forever because the above conditions cause "ret" not to be updated and the cur_index cannot be changed into the bigger one. (So, radix_tree_gang_lookup_tag_slot() cannot return forever.) radix_tree_gang_lookup_tag_slot(): 1178 while (ret < max_items) { 1179 unsigned int slots_found; 1180 unsigned long next_index; /* Index of next search */ 1181 1182 if (cur_index > max_index) 1183 break; 1184 slots_found = __lookup_tag(node, results + ret, 1185 cur_index, max_items - ret, &next_index, tag); 1186 ret += slots_found; // cannot update ret because slots_found == 0. // so, this while loops forever. 1187 if (next_index == 0) 1188 break; 1189 cur_index = next_index; 1190 } (2) Why does __lookup_tag() return with 0 and doesn't update the index? Assuming the following: - the one of the slot in radix_tree_node is NULL. - the one of the tag which corresponds to the slot sets with PAGECACHE_TAG_TOWRITE or other. - In a certain height(!=0), the corresponding index is 0. a) __lookup_tag() notices that the tag is set. 1005 static unsigned int 1006 __lookup_tag(struct radix_tree_node *slot, void ***results, unsigned long index, 1007 unsigned int max_items, unsigned long *next_index, unsigned int tag) 1008 { 1009 unsigned int nr_found = 0; 1010 unsigned int shift, height; 1011 1012 height = slot->height; 1013 if (height == 0) 1014 goto out; 1015 shift = (height-1) * RADIX_TREE_MAP_SHIFT; 1016 1017 while (height > 0) { 1018 unsigned long i = (index >> shift) & RADIX_TREE_MAP_MASK ; 1019 1020 for (;;) { 1021 if (tag_get(slot, tag, i)) 1022 break; ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ * the index is not updated yet. b) __lookup_tag() notices that the slot is NULL. 1023 index &= ~((1UL << shift) - 1); 1024 index += 1UL << shift; 1025 if (index == 0) 1026 goto out; /* 32-bit wraparound */ 1027 i++; 1028 if (i == RADIX_TREE_MAP_SIZE) 1029 goto out; 1030 } 1031 height--; 1032 if (height == 0) { /* Bottom level: grab some items */ ... 1055 } 1056 shift -= RADIX_TREE_MAP_SHIFT; 1057 slot = rcu_dereference_raw(slot->slots[i]); 1058 if (slot == NULL) 1059 break; ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ c) __lookup_tag() doesn't update the index and return with 0. 1060 } 1061 out: 1062 *next_index = index; ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 1063 return nr_found; 1064 } (3) Why is the slot NULL even if the tag is set? Because radix_tree_range_tag_if_tagged() always sets the root tag with PAGECACHE_TAG_TOWRITE if the root tag is set with PAGECACHE_TAG_DIRTY, even if there is no tag which can be set with PAGECACHE_TAG_TOWRITE in the specified range (from *first_indexp to last_index). Of course, some PAGECACHE_TAG_DIRTY nodes must exist outside the specified range. (radix_tree_range_tag_if_tagged() is called only from tag_pages_for_writeback()) 640 unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root, 641 unsigned long *first_indexp, unsigned long last_index, 642 unsigned long nr_to_tag, 643 unsigned int iftag, unsigned int settag) 644 { 645 unsigned int height = root->height; 646 struct radix_tree_path path[height]; 647 struct radix_tree_path *pathp = path; 648 struct radix_tree_node *slot; 649 unsigned int shift; 650 unsigned long tagged = 0; 651 unsigned long index = *first_indexp; 652 653 last_index = min(last_index, radix_tree_maxindex(height)); 654 if (index > last_index) 655 return 0; 656 if (!nr_to_tag) 657 return 0; 658 if (!root_tag_get(root, iftag)) { 659 *first_indexp = last_index + 1; 660 return 0; 661 } 662 if (height == 0) { 663 *first_indexp = last_index + 1; 664 root_tag_set(root, settag); 665 return 1; 666 } ... 733 root_tag_set(root, settag); ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 734 *first_indexp = index; 735 736 return tagged; 737 } As the result, there is no radix_tree_node which is set with PAGECACHE_TAG_TOWRITE but the root tag(radix_tree_root) is set with PAGECACHE_TAG_TOWRITE. [figure: inside radix_tree] (Please see the figure with typewriter font) =========================================== [roottag = DIRTY] | tag=0:NOTHING tag[0 0 0 1] 1:DIRTY [x x x +] 2:WRITEBACK | 3:DIRTY,WRITEBACK p 4:TOWRITE <---> 5:DIRTY,TOWRITE ... specified range (index: 0 to 2) * There is no DIRTY tag within the specified range. (But there is a DIRTY tag outside that range.) | | | | | | | | | after calling tag_pages_for_writeback() | | | | | | | | | v v v v v v v v v [roottag = DIRTY,TOWRITE] | p is "page". tag[0 0 0 1] x is NULL. [x x x +] +- is a pointer to "page". | p * But TOWRITE tag is set on the root tag. ============================================ After that, radix_tree_extend() via radix_tree_insert() is called when the page is added. This function sets the new radix_tree_node with PAGECACHE_TAG_TOWRITE to succeed the status of the root tag. 246 static int radix_tree_extend(struct radix_tree_root *root, unsigned long index) 247 { 248 struct radix_tree_node *node; 249 unsigned int height; 250 int tag; 251 252 /* Figure out what the height should be. */ 253 height = root->height + 1; 254 while (index > radix_tree_maxindex(height)) 255 height++; 256 257 if (root->rnode == NULL) { 258 root->height = height; 259 goto out; 260 } 261 262 do { 263 unsigned int newheight; 264 if (!(node = radix_tree_node_alloc(root))) 265 return -ENOMEM; 266 267 /* Increase the height. */ 268 node->slots[0] = radix_tree_indirect_to_ptr(root->rnode); 269 270 /* Propagate the aggregated tag info into the new root */ 271 for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++) { 272 if (root_tag_get(root, tag)) 273 tag_set(node, tag, 0); ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 274 } =========================================== [roottag = DIRTY,TOWRITE] | : tag[0 0 0 1] [0 0 0 0] [x x x +] [+ x x x] | | p p (new page) | | | | | | | | | after calling radix_tree_insert | | | | | | | | | v v v v v v v v v [roottag = DIRTY,TOWRITE] | tag [5 0 0 0] * DIRTY and TOWRITE tags are [+ + x x] succeeded to the new node. | | tag [0 0 0 1] [0 0 0 0] [x x x +] [+ x x x] | | p p ============================================ After that, the index 3 page is released by remove_from_page_cache(). Then we can make the situation that the tag is set with PAGECACHE_TAG_TOWRITE and that the slot which corresponds to the tag is NULL. =========================================== [roottag = DIRTY,TOWRITE] | tag [5 0 0 0] [+ + x x] | | tag [0 0 0 1] [0 0 0 0] [x x x +] [+ x x x] | | p p (remove) | | | | | | | | | after calling remove_page_cache | | | | | | | | | v v v v v v v v v [roottag = DIRTY,TOWRITE] | tag [4 0 0 0] * Only DIRTY tag is cleared [x + x x] because no TOWRITE tag is existed | in the bottom node. [0 0 0 0] [+ x x x] | p ============================================ To solve this problem Change to that radix_tree_tag_if_tagged() doesn't tag the root tag if it doesn't set any tags within the specified range. Like this. ============================================ 640 unsigned long radix_tree_range_tag_if_tagged(struct radix_tree_root *root, 641 unsigned long *first_indexp, unsigned long last_index, 642 unsigned long nr_to_tag, 643 unsigned int iftag, unsigned int settag) 644 { 650 unsigned long tagged = 0; ... 733 if (tagged) ^^^^^^^^^^^^^^^^^^^^^^^^ 734 root_tag_set(root, settag); 735 *first_indexp = index; 736 737 return tagged; 738 } ============================================ Signed-off-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com> Acked-by: Jan Kara <jack@suse.cz> Cc: Dave Chinner <david@fromorbit.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>