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2013-12-08random32: fix off-by-one in seeding requirementDaniel Borkmann
[ Upstream commit 51c37a70aaa3f95773af560e6db3073520513912 ] For properly initialising the Tausworthe generator [1], we have a strict seeding requirement, that is, s1 > 1, s2 > 7, s3 > 15. Commit 697f8d0348 ("random32: seeding improvement") introduced a __seed() function that imposes boundary checks proposed by the errata paper [2] to properly ensure above conditions. However, we're off by one, as the function is implemented as: "return (x < m) ? x + m : x;", and called with __seed(X, 1), __seed(X, 7), __seed(X, 15). Thus, an unwanted seed of 1, 7, 15 would be possible, whereas the lower boundary should actually be of at least 2, 8, 16, just as GSL does. Fix this, as otherwise an initialization with an unwanted seed could have the effect that Tausworthe's PRNG properties cannot not be ensured. Note that this PRNG is *not* used for cryptography in the kernel. [1] http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps [2] http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.ps Joint work with Hannes Frederic Sowa. Fixes: 697f8d0348a6 ("random32: seeding improvement") Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Florian Weimer <fweimer@redhat.com> Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-12-04vsprintf: check real user/group id for %pKRyan Mallon
commit 312b4e226951f707e120b95b118cbc14f3d162b2 upstream. Some setuid binaries will allow reading of files which have read permission by the real user id. This is problematic with files which use %pK because the file access permission is checked at open() time, but the kptr_restrict setting is checked at read() time. If a setuid binary opens a %pK file as an unprivileged user, and then elevates permissions before reading the file, then kernel pointer values may be leaked. This happens for example with the setuid pppd application on Ubuntu 12.04: $ head -1 /proc/kallsyms 00000000 T startup_32 $ pppd file /proc/kallsyms pppd: In file /proc/kallsyms: unrecognized option 'c1000000' This will only leak the pointer value from the first line, but other setuid binaries may leak more information. Fix this by adding a check that in addition to the current process having CAP_SYSLOG, that effective user and group ids are equal to the real ids. If a setuid binary reads the contents of a file which uses %pK then the pointer values will be printed as NULL if the real user is unprivileged. Update the sysctl documentation to reflect the changes, and also correct the documentation to state the kptr_restrict=0 is the default. This is a only temporary solution to the issue. The correct solution is to do the permission check at open() time on files, and to replace %pK with a function which checks the open() time permission. %pK uses in printk should be removed since no sane permission check can be done, and instead protected by using dmesg_restrict. Signed-off-by: Ryan Mallon <rmallon@gmail.com> Cc: Kees Cook <keescook@chromium.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Joe Perches <joe@perches.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-11-13lib/scatterlist.c: don't flush_kernel_dcache_page on slab pageMing Lei
commit 3d77b50c5874b7e923be946ba793644f82336b75 upstream. Commit b1adaf65ba03 ("[SCSI] block: add sg buffer copy helper functions") introduces two sg buffer copy helpers, and calls flush_kernel_dcache_page() on pages in SG list after these pages are written to. Unfortunately, the commit may introduce a potential bug: - Before sending some SCSI commands, kmalloc() buffer may be passed to block layper, so flush_kernel_dcache_page() can see a slab page finally - According to cachetlb.txt, flush_kernel_dcache_page() is only called on "a user page", which surely can't be a slab page. - ARCH's implementation of flush_kernel_dcache_page() may use page mapping information to do optimization so page_mapping() will see the slab page, then VM_BUG_ON() is triggered. Aaro Koskinen reported the bug on ARM/kirkwood when DEBUG_VM is enabled, and this patch fixes the bug by adding test of '!PageSlab(miter->page)' before calling flush_kernel_dcache_page(). Signed-off-by: Ming Lei <ming.lei@canonical.com> Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi> Tested-by: Simon Baatz <gmbnomis@gmail.com> Cc: Russell King - ARM Linux <linux@arm.linux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Tejun Heo <tj@kernel.org> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-13mm, show_mem: suppress page counts in non-blockable contextsDavid Rientjes
commit 4b59e6c4730978679b414a8da61514a2518da512 upstream. On large systems with a lot of memory, walking all RAM to determine page types may take a half second or even more. In non-blockable contexts, the page allocator will emit a page allocation failure warning unless __GFP_NOWARN is specified. In such contexts, irqs are typically disabled and such a lengthy delay may even result in NMI watchdog timeouts. To fix this, suppress the page walk in such contexts when printing the page allocation failure warning. Signed-off-by: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@suse.de> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Dave Hansen <dave@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Xishi Qiu <qiuxishi@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-06-07klist: del waiter from klist_remove_waiters before wakeup waitting processwang, biao
commit ac5a2962b02f57dea76d314ef2521a2170b28ab6 upstream. There is a race between klist_remove and klist_release. klist_remove uses a local var waiter saved on stack. When klist_release calls wake_up_process(waiter->process) to wake up the waiter, waiter might run immediately and reuse the stack. Then, klist_release calls list_del(&waiter->list) to change previous wait data and cause prior waiter thread corrupt. The patch fixes it against kernel 3.9. Signed-off-by: wang, biao <biao.wang@intel.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-16kobject: fix kset_find_obj() race with concurrent last kobject_put()Linus Torvalds
commit a49b7e82cab0f9b41f483359be83f44fbb6b4979 upstream. Anatol Pomozov identified a race condition that hits module unloading and re-loading. To quote Anatol: "This is a race codition that exists between kset_find_obj() and kobject_put(). kset_find_obj() might return kobject that has refcount equal to 0 if this kobject is freeing by kobject_put() in other thread. Here is timeline for the crash in case if kset_find_obj() searches for an object tht nobody holds and other thread is doing kobject_put() on the same kobject: THREAD A (calls kset_find_obj()) THREAD B (calls kobject_put()) splin_lock() atomic_dec_return(kobj->kref), counter gets zero here ... starts kobject cleanup .... spin_lock() // WAIT thread A in kobj_kset_leave() iterate over kset->list atomic_inc(kobj->kref) (counter becomes 1) spin_unlock() spin_lock() // taken // it does not know that thread A increased counter so it remove obj from list spin_unlock() vfree(module) // frees module object with containing kobj // kobj points to freed memory area!! kobject_put(kobj) // OOPS!!!! The race above happens because module.c tries to use kset_find_obj() when somebody unloads module. The module.c code was introduced in commit 6494a93d55fa" Anatol supplied a patch specific for module.c that worked around the problem by simply not using kset_find_obj() at all, but rather than make a local band-aid, this just fixes kset_find_obj() to be thread-safe using the proper model of refusing the get a new reference if the refcount has already dropped to zero. See examples of this proper refcount handling not only in the kref documentation, but in various other equivalent uses of this pattern by grepping for atomic_inc_not_zero(). [ Side note: the module race does indicate that module loading and unloading is not properly serialized wrt sysfs information using the module mutex. That may require further thought, but this is the correct fix at the kobject layer regardless. ] Reported-analyzed-and-tested-by: Anatol Pomozov <anatol.pomozov@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-04idr: fix a subtle bug in idr_get_next()Tejun Heo
commit 6cdae7416a1c45c2ce105a78187d9b7e8feb9e24 upstream. The iteration logic of idr_get_next() is borrowed mostly verbatim from idr_for_each(). It walks down the tree looking for the slot matching the current ID. If the matching slot is not found, the ID is incremented by the distance of single slot at the given level and repeats. The implementation assumes that during the whole iteration id is aligned to the layer boundaries of the level closest to the leaf, which is true for all iterations starting from zero or an existing element and thus is fine for idr_for_each(). However, idr_get_next() may be given any point and if the starting id hits in the middle of a non-existent layer, increment to the next layer will end up skipping the same offset into it. For example, an IDR with IDs filled between [64, 127] would look like the following. [ 0 64 ... ] /----/ | | | NULL [ 64 ... 127 ] If idr_get_next() is called with 63 as the starting point, it will try to follow down the pointer from 0. As it is NULL, it will then try to proceed to the next slot in the same level by adding the slot distance at that level which is 64 - making the next try 127. It goes around the loop and finds and returns 127 skipping [64, 126]. Note that this bug also triggers in idr_for_each_entry() loop which deletes during iteration as deletions can make layers go away leaving the iteration with unaligned ID into missing layers. Fix it by ensuring proceeding to the next slot doesn't carry over the unaligned offset - ie. use round_up(id + 1, slot_distance) instead of id += slot_distance. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: David Teigland <teigland@redhat.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-11digsig: Fix memory leakage in digsig_verify_rsa()YOSHIFUJI Hideaki
commit 7810cc1e7721220f1ed2a23ca95113d6434f6dcd upstream. digsig_verify_rsa() does not free kmalloc'ed buffer returned by mpi_get_buffer(). Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-01-11lib: atomic64: Initialize locks statically to fix early usersStephen Boyd
commit fcc16882ac4532aaa644bff444f0c5d6228ba71e upstream. The atomic64 library uses a handful of static spin locks to implement atomic 64-bit operations on architectures without support for atomic 64-bit instructions. Unfortunately, the spinlocks are initialized in a pure initcall and that is too late for the vfs namespace code which wants to use atomic64 operations before the initcall is run. This became a problem as of commit 8823c079ba71: "vfs: Add setns support for the mount namespace". This leads to BUG messages such as: BUG: spinlock bad magic on CPU#0, swapper/0/0 lock: atomic64_lock+0x240/0x400, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0 do_raw_spin_lock+0x158/0x198 _raw_spin_lock_irqsave+0x4c/0x58 atomic64_add_return+0x30/0x5c alloc_mnt_ns.clone.14+0x44/0xac create_mnt_ns+0xc/0x54 mnt_init+0x120/0x1d4 vfs_caches_init+0xe0/0x10c start_kernel+0x29c/0x300 coming out early on during boot when spinlock debugging is enabled. Fix this by initializing the spinlocks statically at compile time. Reported-and-tested-by: Vaibhav Bedia <vaibhav.bedia@ti.com> Tested-by: Tony Lindgren <tony@atomide.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-12-03MPI: Fix compilation on MIPS with GCC 4.4 and newerManuel Lauss
commit a3cea9894157c20a5b1ec08b7e0b5f2019740c10 upstream. Since 4.4 GCC on MIPS no longer recognizes the "h" constraint, leading to this build failure: CC lib/mpi/generic_mpih-mul1.o lib/mpi/generic_mpih-mul1.c: In function 'mpihelp_mul_1': lib/mpi/generic_mpih-mul1.c:50:3: error: impossible constraint in 'asm' This patch updates MPI with the latest umul_ppm implementations for MIPS. Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com> Cc: Linux-MIPS <linux-mips@linux-mips.org> Cc: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Cc: James Morris <jmorris@namei.org> Patchwork: https://patchwork.linux-mips.org/patch/4612/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Cc: Shuah Khan <shuah.khan@hp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-31genalloc: stop crashing the system when destroying a poolThadeu Lima de Souza Cascardo
commit eedce141cd2dad8d0cefc5468ef41898949a7031 upstream. The genalloc code uses the bitmap API from include/linux/bitmap.h and lib/bitmap.c, which is based on long values. Both bitmap_set from lib/bitmap.c and bitmap_set_ll, which is the lockless version from genalloc.c, use BITMAP_LAST_WORD_MASK to set the first bits in a long in the bitmap. That one uses (1 << bits) - 1, 0b111, if you are setting the first three bits. This means that the API counts from the least significant bits (LSB from now on) to the MSB. The LSB in the first long is bit 0, then. The same works for the lookup functions. The genalloc code uses longs for the bitmap, as it should. In include/linux/genalloc.h, struct gen_pool_chunk has unsigned long bits[0] as its last member. When allocating the struct, genalloc should reserve enough space for the bitmap. This should be a proper number of longs that can fit the amount of bits in the bitmap. However, genalloc allocates an integer number of bytes that fit the amount of bits, but may not be an integer amount of longs. 9 bytes, for example, could be allocated for 70 bits. This is a problem in itself if the Least Significat Bit in a long is in the byte with the largest address, which happens in Big Endian machines. This means genalloc is not allocating the byte in which it will try to set or check for a bit. This may end up in memory corruption, where genalloc will try to set the bits it has not allocated. In fact, genalloc may not set these bits because it may find them already set, because they were not zeroed since they were not allocated. And that's what causes a BUG when gen_pool_destroy is called and check for any set bits. What really happens is that genalloc uses kmalloc_node with __GFP_ZERO on gen_pool_add_virt. With SLAB and SLUB, this means the whole slab will be cleared, not only the requested bytes. Since struct gen_pool_chunk has a size that is a multiple of 8, and slab sizes are multiples of 8, we get lucky and allocate and clear the right amount of bytes. Hower, this is not the case with SLOB or with older code that did memset after allocating instead of using __GFP_ZERO. So, a simple module as this (running 3.6.0), will cause a crash when rmmod'ed. [root@phantom-lp2 foo]# cat foo.c #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/genalloc.h> MODULE_LICENSE("GPL"); MODULE_VERSION("0.1"); static struct gen_pool *foo_pool; static __init int foo_init(void) { int ret; foo_pool = gen_pool_create(10, -1); if (!foo_pool) return -ENOMEM; ret = gen_pool_add(foo_pool, 0xa0000000, 32 << 10, -1); if (ret) { gen_pool_destroy(foo_pool); return ret; } return 0; } static __exit void foo_exit(void) { gen_pool_destroy(foo_pool); } module_init(foo_init); module_exit(foo_exit); [root@phantom-lp2 foo]# zcat /proc/config.gz | grep SLOB CONFIG_SLOB=y [root@phantom-lp2 foo]# insmod ./foo.ko [root@phantom-lp2 foo]# rmmod foo ------------[ cut here ]------------ kernel BUG at lib/genalloc.c:243! cpu 0x4: Vector: 700 (Program Check) at [c0000000bb0e7960] pc: c0000000003cb50c: .gen_pool_destroy+0xac/0x110 lr: c0000000003cb4fc: .gen_pool_destroy+0x9c/0x110 sp: c0000000bb0e7be0 msr: 8000000000029032 current = 0xc0000000bb0e0000 paca = 0xc000000006d30e00 softe: 0 irq_happened: 0x01 pid = 13044, comm = rmmod kernel BUG at lib/genalloc.c:243! [c0000000bb0e7ca0] d000000004b00020 .foo_exit+0x20/0x38 [foo] [c0000000bb0e7d20] c0000000000dff98 .SyS_delete_module+0x1a8/0x290 [c0000000bb0e7e30] c0000000000097d4 syscall_exit+0x0/0x94 --- Exception: c00 (System Call) at 000000800753d1a0 SP (fffd0b0e640) is in userspace Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Benjamin Gaignard <benjamin.gaignard@stericsson.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-13lib/gcd.c: prevent possible div by 0Davidlohr Bueso
commit e96875677fb2b7cb739c5d7769824dff7260d31d upstream. Account for all properties when a and/or b are 0: gcd(0, 0) = 0 gcd(a, 0) = a gcd(0, b) = b Fixes no known problems in current kernels. Signed-off-by: Davidlohr Bueso <dave@gnu.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-02digsig: add hash size comparision on signature verificationDmitry Kasatkin
commit bc01637a80f5b670bd70a0279d3f93fa8de1c96d upstream. When pkcs_1_v1_5_decode_emsa() returns without error and hash sizes do not match, hash comparision is not done and digsig_verify_rsa() returns no error. This is a bug and this patch fixes it. The bug was introduced in v3.3 by commit b35e286a640f ("lib/digsig: pkcs_1_v1_5_decode_emsa cleanup"). Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16bql: Avoid possible inconsistent calculation.Hiroaki SHIMODA
[ Upstream commit 914bec1011a25f65cdc94988a6f974bfb9a3c10d ] dql->num_queued could change while processing dql_completed(). To provide consistent calculation, added an on stack variable. Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com> Cc: Tom Herbert <therbert@google.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Denys Fedoryshchenko <denys@visp.net.lb> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16bql: Avoid unneeded limit decrement.Hiroaki SHIMODA
[ Upstream commit 25426b794efdc70dde7fd3134dc56fac3e7d562d ] When below pattern is observed, TIME dql_queued() dql_completed() | a) initial state | | b) X bytes queued V c) Y bytes queued d) X bytes completed e) Z bytes queued f) Y bytes completed a) dql->limit has already some value and there is no in-flight packet. b) X bytes queued. c) Y bytes queued and excess limit. d) X bytes completed and dql->prev_ovlimit is set and also dql->prev_num_queued is set Y. e) Z bytes queued. f) Y bytes completed. inprogress and prev_inprogress are true. At f), according to the comment, all_prev_completed becomes true and limit should be increased. But POSDIFF() ignores (completed == dql->prev_num_queued) case, so limit is decreased. Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com> Cc: Tom Herbert <therbert@google.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Denys Fedoryshchenko <denys@visp.net.lb> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16bql: Fix POSDIFF() to integer overflow aware.Hiroaki SHIMODA
[ Upstream commit 0cfd32b736ae0c36b42697584811042726c07cba ] POSDIFF() fails to take into account integer overflow case. Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com> Cc: Tom Herbert <therbert@google.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Denys Fedoryshchenko <denys@visp.net.lb> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-17btree: fix tree corruption in btree_get_prev()Roland Dreier
commit cbf8ae32f66a9ceb8907ad9e16663c2a29e48990 upstream. The memory the parameter __key points to is used as an iterator in btree_get_prev(), so if we save off a bkey() pointer in retry_key and then assign that to __key, we'll end up corrupting the btree internals when we do eg longcpy(__key, bkey(geo, node, i), geo->keylen); to return the key value. What we should do instead is use longcpy() to copy the key value that retry_key points to __key. This can cause a btree to get corrupted by seemingly read-only operations such as btree_for_each_safe. [akpm@linux-foundation.org: avoid the double longcpy()] Signed-off-by: Roland Dreier <roland@purestorage.com> Acked-by: Joern Engel <joern@logfs.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-10radix-tree: fix contiguous iteratorKonstantin Khlebnikov
commit fffaee365fded09f9ebf2db19066065fa54323c3 upstream. This patch fixes bug in macro radix_tree_for_each_contig(). If radix_tree_next_slot() sees NULL in next slot it returns NULL, but following radix_tree_next_chunk() switches iterating into next chunk. As result iterating becomes non-contiguous and breaks vfs "splice" and all its users. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Reported-and-bisected-by: Hans de Bruin <jmdebruin@xmsnet.nl> Reported-and-bisected-by: Ondrej Zary <linux@rainbow-software.org> Reported-bisected-and-tested-by: Toralf Förster <toralf.foerster@gmx.de> Link: https://lkml.org/lkml/2012/6/5/64 Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-18mpi: Avoid using freed pointer in mpi_lshift_limbs()Jesper Juhl
At the start of the function we assign 'a->d' to 'ap'. Then we use the RESIZE_IF_NEEDED macro on 'a' - this may free 'a->d' and replace it with newly allocaetd storage. In that case, we'll be operating on freed memory further down in the function when we index into 'ap[]'. Since we don't actually need 'ap' until after the use of the RESIZE_IF_NEEDED macro we can just delay the assignment to it until after we've potentially resized, thus avoiding the issue. While I was there anyway I also changed the integer variable 'n' to be const. It might as well be since we only assign to it once and use it as a constant, and then the compiler will tell us if we ever assign to it in the future. Signed-off-by: Jesper Juhl <jj@chaosbits.net> Acked-by: Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-04-10kobject: provide more diagnostic info for kobject_add_internal() failuresDan Williams
1/ convert open-coded KERN_ERR+dump_stack() to WARN(), so that automated tools pick up this warning. 2/ include the 'child' and 'parent' kobject names. This information was useful for tracking down the case where scsi invoked device_del() on a parent object and subsequently invoked device_add() on a child. Now the warning looks like: kobject_add_internal failed for target8:0:16 (error: -2 parent: end_device-8:0:24) Pid: 2942, comm: scsi_scan_8 Not tainted 3.3.0-rc7-isci+ #2 Call Trace: [<ffffffff8125e551>] kobject_add_internal+0x1c1/0x1f3 [<ffffffff81075149>] ? trace_hardirqs_on+0xd/0xf [<ffffffff8125e659>] kobject_add_varg+0x41/0x50 [<ffffffff8125e723>] kobject_add+0x64/0x66 [<ffffffff8131124b>] device_add+0x12d/0x63a [<ffffffff8125e0ef>] ? kobject_put+0x4c/0x50 [<ffffffff8132f370>] scsi_sysfs_add_sdev+0x4e/0x28a [<ffffffff8132dce3>] do_scan_async+0x9c/0x145 Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: James Bottomley <JBottomley@parallels.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-03-29Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 updates from Ingo Molnar. This touches some non-x86 files due to the sanitized INLINE_SPIN_UNLOCK config usage. Fixed up trivial conflicts due to just header include changes (removing headers due to cpu_idle() merge clashing with the <asm/system.h> split). * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic/amd: Be more verbose about LVT offset assignments x86, tls: Off by one limit check x86/ioapic: Add io_apic_ops driver layer to allow interception x86/olpc: Add debugfs interface for EC commands x86: Merge the x86_32 and x86_64 cpu_idle() functions x86/kconfig: Remove CONFIG_TR=y from the defconfigs x86: Stop recursive fault in print_context_stack after stack overflow x86/io_apic: Move and reenable irq only when CONFIG_GENERIC_PENDING_IRQ=y x86/apic: Add separate apic_id_valid() functions for selected apic drivers locking/kconfig: Simplify INLINE_SPIN_UNLOCK usage x86/kconfig: Update defconfigs x86: Fix excessive MSR print out when show_msr is not specified
2012-03-28Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds
Merge third batch of patches from Andrew Morton: - Some MM stragglers - core SMP library cleanups (on_each_cpu_mask) - Some IPI optimisations - kexec - kdump - IPMI - the radix-tree iterator work - various other misc bits. "That'll do for -rc1. I still have ~10 patches for 3.4, will send those along when they've baked a little more." * emailed from Andrew Morton <akpm@linux-foundation.org>: (35 commits) backlight: fix typo in tosa_lcd.c crc32: add help text for the algorithm select option mm: move hugepage test examples to tools/testing/selftests/vm mm: move slabinfo.c to tools/vm mm: move page-types.c from Documentation to tools/vm selftests/Makefile: make `run_tests' depend on `all' selftests: launch individual selftests from the main Makefile radix-tree: use iterators in find_get_pages* functions radix-tree: rewrite gang lookup using iterator radix-tree: introduce bit-optimized iterator fs/proc/namespaces.c: prevent crash when ns_entries[] is empty nbd: rename the nbd_device variable from lo to nbd pidns: add reboot_pid_ns() to handle the reboot syscall sysctl: use bitmap library functions ipmi: use locks on watchdog timeout set on reboot ipmi: simplify locking ipmi: fix message handling during panics ipmi: use a tasklet for handling received messages ipmi: increase KCS timeouts ipmi: decrease the IPMI message transaction time in interrupt mode ...
2012-03-28crc32: add help text for the algorithm select optionDarrick J. Wong
Add help text to the crc32 algorithm selection option in Kconfig. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Reported-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28radix-tree: rewrite gang lookup using iteratorKonstantin Khlebnikov
Rewrite radix_tree_gang_lookup_* functions using the new radix-tree iterator. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Tested-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28radix-tree: introduce bit-optimized iteratorKonstantin Khlebnikov
A series of radix tree cleanups, and usage of them in the core pagecache code. Micro-benchmark: lookup 14 slots (typical page-vector size) in radix-tree there earch <step> slot filled and tagged before/after - nsec per full scan through tree * Intel Sandy Bridge i7-2620M 4Mb L3 New code always faster * AMD Athlon 6000+ 2x1Mb L2, without L3 New code generally faster, Minor degradation (marked with "*") for huge sparse trees * i386 on Sandy Bridge New code faster for common cases: tagged and dense trees. Some degradations for non-tagged lookup on sparse trees. Ideally, there might help __ffs() analog for searching first non-zero long element in array, gcc sometimes cannot optimize this loop corretly. Numbers: CPU: Intel Sandy Bridge i7-2620M 4Mb L3 radix-tree with 1024 slots: tagged lookup step 1 before 7156 after 3613 step 2 before 5399 after 2696 step 3 before 4779 after 1928 step 4 before 4456 after 1429 step 5 before 4292 after 1213 step 6 before 4183 after 1052 step 7 before 4157 after 951 step 8 before 4016 after 812 step 9 before 3952 after 851 step 10 before 3937 after 732 step 11 before 4023 after 709 step 12 before 3872 after 657 step 13 before 3892 after 633 step 14 before 3720 after 591 step 15 before 3879 after 578 step 16 before 3561 after 513 normal lookup step 1 before 4266 after 3301 step 2 before 2695 after 2129 step 3 before 2083 after 1712 step 4 before 1801 after 1534 step 5 before 1628 after 1313 step 6 before 1551 after 1263 step 7 before 1475 after 1185 step 8 before 1432 after 1167 step 9 before 1373 after 1092 step 10 before 1339 after 1134 step 11 before 1292 after 1056 step 12 before 1319 after 1030 step 13 before 1276 after 1004 step 14 before 1256 after 987 step 15 before 1228 after 992 step 16 before 1247 after 999 radix-tree with 1024*1024*128 slots: tagged lookup step 1 before 1086102841 after 674196409 step 2 before 816839155 after 498138306 step 7 before 599728907 after 240676762 step 15 before 555729253 after 185219677 step 63 before 606637748 after 128585664 step 64 before 608384432 after 102945089 step 65 before 596987114 after 123996019 step 128 before 304459225 after 56783056 step 256 before 158846855 after 31232481 step 512 before 86085652 after 18950595 step 12345 before 6517189 after 1674057 normal lookup step 1 before 626064869 after 544418266 step 2 before 418809975 after 336321473 step 7 before 242303598 after 207755560 step 15 before 208380563 after 176496355 step 63 before 186854206 after 167283638 step 64 before 176188060 after 170143976 step 65 before 185139608 after 167487116 step 128 before 88181865 after 86913490 step 256 before 45733628 after 45143534 step 512 before 24506038 after 23859036 step 12345 before 2177425 after 2018662 * AMD Athlon 6000+ 2x1Mb L2, without L3 radix-tree with 1024 slots: tag-lookup step 1 before 8164 after 5379 step 2 before 5818 after 5581 step 3 before 4959 after 4213 step 4 before 4371 after 3386 step 5 before 4204 after 2997 step 6 before 4950 after 2744 step 7 before 4598 after 2480 step 8 before 4251 after 2288 step 9 before 4262 after 2243 step 10 before 4175 after 2131 step 11 before 3999 after 2024 step 12 before 3979 after 1994 step 13 before 3842 after 1929 step 14 before 3750 after 1810 step 15 before 3735 after 1810 step 16 before 3532 after 1660 normal-lookup step 1 before 7875 after 5847 step 2 before 4808 after 4071 step 3 before 4073 after 3462 step 4 before 3677 after 3074 step 5 before 4308 after 2978 step 6 before 3911 after 3807 step 7 before 3635 after 3522 step 8 before 3313 after 3202 step 9 before 3280 after 3257 step 10 before 3166 after 3083 step 11 before 3066 after 3026 step 12 before 2985 after 2982 step 13 before 2925 after 2924 step 14 before 2834 after 2808 step 15 before 2805 after 2803 step 16 before 2647 after 2622 radix-tree with 1024*1024*128 slots: tag-lookup step 1 before 1288059720 after 951736580 step 2 before 961292300 after 884212140 step 7 before 768905140 after 547267580 step 15 before 771319480 after 456550640 step 63 before 504847640 after 242704304 step 64 before 392484800 after 177920786 step 65 before 491162160 after 246895264 step 128 before 208084064 after 97348392 step 256 before 112401035 after 51408126 step 512 before 75825834 after 29145070 step 12345 before 5603166 after 2847330 normal-lookup step 1 before 1025677120 after 861375100 step 2 before 647220080 after 572258540 step 7 before 505518960 after 484041813 step 15 before 430483053 after 444815320 * step 63 before 388113453 after 404250546 * step 64 before 374154666 after 396027440 * step 65 before 381423973 after 396704853 * step 128 before 190078700 after 202619384 * step 256 before 100886756 after 102829108 * step 512 before 64074505 after 56158720 step 12345 before 4237289 after 4422299 * * i686 on Sandy bridge radix-tree with 1024 slots: tagged lookup step 1 before 7990 after 4019 step 2 before 5698 after 2897 step 3 before 5013 after 2475 step 4 before 4630 after 1721 step 5 before 4346 after 1759 step 6 before 4299 after 1556 step 7 before 4098 after 1513 step 8 before 4115 after 1222 step 9 before 3983 after 1390 step 10 before 4077 after 1207 step 11 before 3921 after 1231 step 12 before 3894 after 1116 step 13 before 3840 after 1147 step 14 before 3799 after 1090 step 15 before 3797 after 1059 step 16 before 3783 after 745 normal lookup step 1 before 5103 after 3499 step 2 before 3299 after 2550 step 3 before 2489 after 2370 step 4 before 2034 after 2302 * step 5 before 1846 after 2268 * step 6 before 1752 after 2249 * step 7 before 1679 after 2164 * step 8 before 1627 after 2153 * step 9 before 1542 after 2095 * step 10 before 1479 after 2109 * step 11 before 1469 after 2009 * step 12 before 1445 after 2039 * step 13 before 1411 after 2013 * step 14 before 1374 after 2046 * step 15 before 1340 after 1975 * step 16 before 1331 after 2000 * radix-tree with 1024*1024*128 slots: tagged lookup step 1 before 1225865377 after 667153553 step 2 before 842427423 after 471533007 step 7 before 609296153 after 276260116 step 15 before 544232060 after 226859105 step 63 before 519209199 after 141343043 step 64 before 588980279 after 141951339 step 65 before 521099710 after 138282060 step 128 before 298476778 after 83390628 step 256 before 149358342 after 43602609 step 512 before 76994713 after 22911077 step 12345 before 5328666 after 1472111 normal lookup step 1 before 819284564 after 533635310 step 2 before 512421605 after 364956155 step 7 before 271443305 after 305721345 * step 15 before 223591630 after 273960216 * step 63 before 190320247 after 217770207 * step 64 before 178538168 after 267411372 * step 65 before 186400423 after 215347937 * step 128 before 88106045 after 140540612 * step 256 before 44812420 after 70660377 * step 512 before 24435438 after 36328275 * step 12345 before 2123924 after 2148062 * bloat-o-meter delta for this patchset + patchset with related shmem cleanups bloat-o-meter: x86_64 add/remove: 4/3 grow/shrink: 5/6 up/down: 928/-939 (-11) function old new delta radix_tree_next_chunk - 499 +499 shmem_unuse 428 554 +126 shmem_radix_tree_replace 131 227 +96 find_get_pages_tag 354 419 +65 find_get_pages_contig 345 407 +62 find_get_pages 362 396 +34 __kstrtab_radix_tree_next_chunk - 22 +22 __ksymtab_radix_tree_next_chunk - 16 +16 __kcrctab_radix_tree_next_chunk - 8 +8 radix_tree_gang_lookup_slot 204 203 -1 static.shmem_xattr_set 384 381 -3 radix_tree_gang_lookup_tag_slot 208 191 -17 radix_tree_gang_lookup 231 187 -44 radix_tree_gang_lookup_tag 247 199 -48 shmem_unlock_mapping 278 190 -88 __lookup 217 - -217 __lookup_tag 242 - -242 radix_tree_locate_item 279 - -279 bloat-o-meter: i386 add/remove: 3/3 grow/shrink: 8/9 up/down: 1075/-1275 (-200) function old new delta radix_tree_next_chunk - 757 +757 shmem_unuse 352 449 +97 find_get_pages_contig 269 322 +53 shmem_radix_tree_replace 113 154 +41 find_get_pages_tag 277 318 +41 dcache_dir_lseek 426 458 +32 __kstrtab_radix_tree_next_chunk - 22 +22 vc_do_resize 968 977 +9 snd_pcm_lib_read1 725 733 +8 __ksymtab_radix_tree_next_chunk - 8 +8 netlbl_cipsov4_list 1120 1127 +7 find_get_pages 293 291 -2 new_slab 467 459 -8 bitfill_unaligned_rev 425 417 -8 radix_tree_gang_lookup_tag_slot 177 146 -31 blk_dump_cmd 267 229 -38 radix_tree_gang_lookup_slot 212 134 -78 shmem_unlock_mapping 221 128 -93 radix_tree_gang_lookup_tag 275 162 -113 radix_tree_gang_lookup 255 126 -129 __lookup 227 - -227 __lookup_tag 271 - -271 radix_tree_locate_item 277 - -277 This patch: Implement a clean, simple and effective radix-tree iteration routine. Iterating divided into two phases: * lookup next chunk in radix-tree leaf node * iterating through slots in this chunk Main iterator function radix_tree_next_chunk() returns pointer to first slot, and stores in the struct radix_tree_iter index of next-to-last slot. For tagged-iterating it also constuct bitmask of tags for retunted chunk. All additional logic implemented as static-inline functions and macroses. Also adds radix_tree_find_next_bit() static-inline variant of find_next_bit() optimized for small constant size arrays, because find_next_bit() too heavy for searching in an array with one/two long elements. [akpm@linux-foundation.org: rework comments a bit] Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Tested-by: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-28lib/cpumask.c: remove __any_online_cpu()Srivatsa S. Bhat
__any_online_cpu() is not optimal and also unnecessary. So, replace its use by faster cpumask_* operations. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Venkatesh Pallipadi <venki@google.com> Cc: Rusty Russell <rusty@rustcorp.com.au> 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>
2012-03-28Merge tag 'split-asm_system_h-for-linus-20120328' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system Pull "Disintegrate and delete asm/system.h" from David Howells: "Here are a bunch of patches to disintegrate asm/system.h into a set of separate bits to relieve the problem of circular inclusion dependencies. I've built all the working defconfigs from all the arches that I can and made sure that they don't break. The reason for these patches is that I recently encountered a circular dependency problem that came about when I produced some patches to optimise get_order() by rewriting it to use ilog2(). This uses bitops - and on the SH arch asm/bitops.h drags in asm-generic/get_order.h by a circuituous route involving asm/system.h. The main difficulty seems to be asm/system.h. It holds a number of low level bits with no/few dependencies that are commonly used (eg. memory barriers) and a number of bits with more dependencies that aren't used in many places (eg. switch_to()). These patches break asm/system.h up into the following core pieces: (1) asm/barrier.h Move memory barriers here. This already done for MIPS and Alpha. (2) asm/switch_to.h Move switch_to() and related stuff here. (3) asm/exec.h Move arch_align_stack() here. Other process execution related bits could perhaps go here from asm/processor.h. (4) asm/cmpxchg.h Move xchg() and cmpxchg() here as they're full word atomic ops and frequently used by atomic_xchg() and atomic_cmpxchg(). (5) asm/bug.h Move die() and related bits. (6) asm/auxvec.h Move AT_VECTOR_SIZE_ARCH here. Other arch headers are created as needed on a per-arch basis." Fixed up some conflicts from other header file cleanups and moving code around that has happened in the meantime, so David's testing is somewhat weakened by that. We'll find out anything that got broken and fix it.. * tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits) Delete all instances of asm/system.h Remove all #inclusions of asm/system.h Add #includes needed to permit the removal of asm/system.h Move all declarations of free_initmem() to linux/mm.h Disintegrate asm/system.h for OpenRISC Split arch_align_stack() out from asm-generic/system.h Split the switch_to() wrapper out of asm-generic/system.h Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h Create asm-generic/barrier.h Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h Disintegrate asm/system.h for Xtensa Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt] Disintegrate asm/system.h for Tile Disintegrate asm/system.h for Sparc Disintegrate asm/system.h for SH Disintegrate asm/system.h for Score Disintegrate asm/system.h for S390 Disintegrate asm/system.h for PowerPC Disintegrate asm/system.h for PA-RISC Disintegrate asm/system.h for MN10300 ...
2012-03-28Remove all #inclusions of asm/system.hDavid Howells
Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: David Howells <dhowells@redhat.com>
2012-03-28Disintegrate asm/system.h for PowerPCDavid Howells
Disintegrate asm/system.h for PowerPC. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> cc: linuxppc-dev@lists.ozlabs.org
2012-03-27Merge branch 'for-linus-3.4-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml Pull UML changes from Richard Weinberger: "Mostly bug fixes and cleanups" * 'for-linus-3.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: (35 commits) um: Update defconfig um: Switch to large mcmodel on x86_64 MTD: Relax dependencies um: Wire CONFIG_GENERIC_IO up um: Serve io_remap_pfn_range() Introduce CONFIG_GENERIC_IO um: allow SUBARCH=x86 um: most of the SUBARCH uses can be killed um: deadlock in line_write_interrupt() um: don't bother trying to rebuild CHECKFLAGS for USER_OBJS um: use the right ifdef around exports in user_syms.c um: a bunch of headers can be killed by using generic-y um: ptrace-generic.h doesn't need user.h um: kill HOST_TASK_PID um: remove pointless include of asm/fixmap.h from asm/pgtable.h um: asm-offsets.h might as well come from underlying arch... um: merge processor_{32,64}.h a bit... um: switch close_chan() to struct line um: race fix: initialize delayed_work *before* registering IRQ um: line->have_irq is never checked... ...
2012-03-25Introduce CONFIG_GENERIC_IORichard Weinberger
There are situations where CONFIG_HAS_IOMEM is too restrictive. For example CONFIG_MTD_NAND_NANDSIM depends on CONFIG_HAS_IOMEM but it works perfectly fine if an architecture without io memory just includes asm-generic/io.h or implements everything defined in it. UML is such a corner case. Signed-off-by: Richard Weinberger <richard@nod.at>
2012-03-24Merge tag 'module-for-3.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux Pull cleanup of fs/ and lib/ users of module.h from Paul Gortmaker: "Fix up files in fs/ and lib/ dirs to only use module.h if they really need it. These are trivial in scope vs the work done previously. We now have things where any few remaining cleanups can be farmed out to arch or subsystem maintainers, and I have done so when possible. What is remaining here represents the bits that don't clearly lie within a single arch/subsystem boundary, like the fs dir and the lib dir. Some duplicate includes arising from overlapping fixes from independent subsystem maintainer submissions are also quashed." Fix up trivial conflicts due to clashes with other include file cleanups (including some due to the previous bug.h cleanup pull). * tag 'module-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: lib: reduce the use of module.h wherever possible fs: reduce the use of module.h wherever possible includecheck: delete any duplicate instances of module.h
2012-03-24Merge tag 'bug-for-3.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux Pull <linux/bug.h> cleanup from Paul Gortmaker: "The changes shown here are to unify linux's BUG support under the one <linux/bug.h> file. Due to historical reasons, we have some BUG code in bug.h and some in kernel.h -- i.e. the support for BUILD_BUG in linux/kernel.h predates the addition of linux/bug.h, but old code in kernel.h wasn't moved to bug.h at that time. As a band-aid, kernel.h was including <asm/bug.h> to pseudo link them. This has caused confusion[1] and general yuck/WTF[2] reactions. Here is an example that violates the principle of least surprise: CC lib/string.o lib/string.c: In function 'strlcat': lib/string.c:225:2: error: implicit declaration of function 'BUILD_BUG_ON' make[2]: *** [lib/string.o] Error 1 $ $ grep linux/bug.h lib/string.c #include <linux/bug.h> $ We've included <linux/bug.h> for the BUG infrastructure and yet we still get a compile fail! [We've not kernel.h for BUILD_BUG_ON.] Ugh - very confusing for someone who is new to kernel development. With the above in mind, the goals of this changeset are: 1) find and fix any include/*.h files that were relying on the implicit presence of BUG code. 2) find and fix any C files that were consuming kernel.h and hence relying on implicitly getting some/all BUG code. 3) Move the BUG related code living in kernel.h to <linux/bug.h> 4) remove the asm/bug.h from kernel.h to finally break the chain. During development, the order was more like 3-4, build-test, 1-2. But to ensure that git history for bisect doesn't get needless build failures introduced, the commits have been reorderd to fix the problem areas in advance. [1] https://lkml.org/lkml/2012/1/3/90 [2] https://lkml.org/lkml/2012/1/17/414" Fix up conflicts (new radeon file, reiserfs header cleanups) as per Paul and linux-next. * tag 'bug-for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: kernel.h: doesn't explicitly use bug.h, so don't include it. bug: consolidate BUILD_BUG_ON with other bug code BUG: headers with BUG/BUG_ON etc. need linux/bug.h bug.h: add include of it to various implicit C users lib: fix implicit users of kernel.h for TAINT_WARN spinlock: macroize assert_spin_locked to avoid bug.h dependency x86: relocate get/set debugreg fcns to include/asm/debugreg.
2012-03-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctlLinus Torvalds
Pull sysctl updates from Eric Biederman: - Rewrite of sysctl for speed and clarity. Insert/remove/Lookup in sysctl are all now O(NlogN) operations, and are no longer bottlenecks in the process of adding and removing network devices. sysctl is now focused on being a filesystem instead of system call and the code can all be found in fs/proc/proc_sysctl.c. Hopefully this means the code is now approachable. Much thanks is owed to Lucian Grinjincu for keeping at this until something was found that was usable. - The recent proc_sys_poll oops found by the fuzzer during hibernation is fixed. * git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/sysctl: (36 commits) sysctl: protect poll() in entries that may go away sysctl: Don't call sysctl_follow_link unless we are a link. sysctl: Comments to make the code clearer. sysctl: Correct error return from get_subdir sysctl: An easier to read version of find_subdir sysctl: fix memset parameters in setup_sysctl_set() sysctl: remove an unused variable sysctl: Add register_sysctl for normal sysctl users sysctl: Index sysctl directories with rbtrees. sysctl: Make the header lists per directory. sysctl: Move sysctl_check_dups into insert_header sysctl: Modify __register_sysctl_paths to take a set instead of a root and an nsproxy sysctl: Replace root_list with links between sysctl_table_sets. sysctl: Add sysctl_print_dir and use it in get_subdir sysctl: Stop requiring explicit management of sysctl directories sysctl: Add a root pointer to ctl_table_set sysctl: Rewrite proc_sys_readdir in terms of first_entry and next_entry sysctl: Rewrite proc_sys_lookup introducing find_entry and lookup_entry. sysctl: Normalize the root_table data structure. sysctl: Factor out insert_header and erase_header ...
2012-03-23procfs: add num_to_str() to speed up /proc/statKAMEZAWA Hiroyuki
== stat_check.py num = 0 with open("/proc/stat") as f: while num < 1000 : data = f.read() f.seek(0, 0) num = num + 1 == perf shows 20.39% stat_check.py [kernel.kallsyms] [k] format_decode 13.41% stat_check.py [kernel.kallsyms] [k] number 12.61% stat_check.py [kernel.kallsyms] [k] vsnprintf 10.85% stat_check.py [kernel.kallsyms] [k] memcpy 4.85% stat_check.py [kernel.kallsyms] [k] radix_tree_lookup 4.43% stat_check.py [kernel.kallsyms] [k] seq_printf This patch removes most of calls to vsnprintf() by adding num_to_str() and seq_print_decimal_ull(), which prints decimal numbers without rich functions provided by printf(). On my 8cpu box. == Before patch == [root@bluextal test]# time ./stat_check.py real 0m0.150s user 0m0.026s sys 0m0.121s == After patch == [root@bluextal test]# time ./stat_check.py real 0m0.055s user 0m0.022s sys 0m0.030s [akpm@linux-foundation.org: remove incorrect comment, use less statck in num_to_str(), move comment from .h to .c, simplify seq_put_decimal_ull()] [andrea@betterlinux.com: avoid breaking the ABI in /proc/stat] Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrea Righi <andrea@betterlinux.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Glauber Costa <glommer@parallels.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Paul Turner <pjt@google.com> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: select an algorithm via KconfigDarrick J. Wong
Allow the kernel builder to choose a crc32* algorithm for the kernel. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: add self-test code for crc32cDarrick J. Wong
Add self-test code for crc32c. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: bolt on crc32cDarrick J. Wong
Reuse the existing crc32 code to stamp out a crc32c implementation. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Bob Pearson <rpearson@systemfabricworks.com> Cc: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: add note about this patchset to crc32.cBob Pearson
Add a comment at the top of crc32.c [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: optimize loop counter for x86Bob Pearson
Add two changes that improve the performance of x86 systems 1. replace main loop with incrementing counter this change improves the performance of the selftest by about 5-6% on Nehalem CPUs. The apparent reason is that the compiler can use the loop index to perform an indexed memory access. This is reported to make the performance of PowerPC CPUs to get worse. 2. replace the rem_len loop with incrementing counter this change improves the performance of the selftest, which has more than the usual number of occurances, by about 1-2% on x86 CPUs. In actual work loads the length is most often a multiple of 4 bytes and this code does not get executed as often if at all. Again this change is reported to make the performance of PowerPC get worse. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: add slice-by-8 algorithm to existing codeBob Pearson
Add slicing-by-8 algorithm to the existing slicing-by-4 algorithm. This consists of: - extend largest BITS size from 32 to 64 - extend tables from tab[4][256] to up to tab[8][256] - Add code for inner loop. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: make CRC_*_BITS definition correspond to actual bit countsBob Pearson
crc32.c provides a choice of one of several algorithms for computing the LSB and LSB versions of the CRC32 checksum based on the parameters CRC_LE_BITS and CRC_BE_BITS. In the original version the values 1, 2, 4 and 8 respectively selected versions of the alrogithm that computed the crc 1, 2, 4 and 32 bits as a time. This patch series adds a new version that computes the CRC 64 bits at a time. To make things easier to understand the parameter has been reinterpreted to actually stand for the number of bits processed in each step of the algorithm so that the old value 8 has been replaced with the value 32. This also allows us to add in a widely used crc algorithm that computes the crc 8 bits at a time called the Sarwate algorithm. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: fix mixing of endian-specific typesBob Pearson
crc32.c in its original version freely mixed u32, __le32 and __be32 types which caused warnings from sparse with __CHECK_ENDIAN__. This patch fixes these by forcing the types to u32. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: miscellaneous cleanupsBob Pearson
Misc cleanup of lib/crc32.c and related files. - remove unnecessary header files. - straighten out some convoluted ifdef's - rewrite some references to 2 dimensional arrays as 1 dimensional arrays to make them correct. I.e. replace tab[i] with tab[0][i]. - a few trivial whitespace changes - fix a warning in gen_crc32tables.c caused by a mismatch in the type of the pointer passed to output table. Since the table is only used at kernel compile time, it is simpler to make the table big enough to hold the largest column size used. One cannot make the column size smaller in output_table because it has to be used by both the le and be tables and they can have different column sizes. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: simplify unit test codeBob Pearson
Replace the unit test provided in crc32.c, which doesn't have a makefile and doesn't compile with current headers, with a simpler self test routine that also gives a measure of performance and runs at module init time. The self test option can be enabled through a configuration option CONFIG_CRC32_SELFTEST. The test stresses the pre and post loops and is thus not very realistic since actual uses will likely have addresses and lengths that are at least 4 byte aligned. However, the main loop is long enough so that the performance is dominated by that loop. The expected values for crc32_le and crc32_be were generated with the original version of crc32.c using CRC_BITS_LE = 8 and CRC_BITS_BE = 8. These values were then used to check all the values of the BITS parameters in both the original and new versions. The performance results show some variability from run to run in spite of attempts to both warm the cache and reduce the amount of OS noise by limiting interrutps during the test. To get comparable results and to analyse options wrt performance the best time reported over a small sample of runs has been taken. [djwong@us.ibm.com: Minor changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: move long comment about crc32 fundamentals to Documentation/Bob Pearson
Move a long comment from lib/crc32.c to Documentation/crc32.txt where it will more likely get read. Edited the resulting document to add an explanation of the slicing-by-n algorithm. [djwong@us.ibm.com: minor changelog tweaks] [akpm@linux-foundation.org: fix typo, per George] Signed-off-by: George Spelvin <linux@horizon.com> Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23crc32: remove two instances of trailing whitespacesBob Pearson
This patchset (re)uses Bob Pearson's crc32 slice-by-8 code to stamp out a software crc32c implementation. It removes the crc32c implementation in crypto/ in favor of using the stamped-out one in lib/. There is also a change to Kconfig so that the kernel builder can pick an implementation best suited for the hardware. The motivation for this patchset is that I am working on adding full metadata checksumming to ext4. As far as performance impact of adding checksumming goes, I see nearly no change with a standard mail server ffsb simulation. On a test that involves only file creation and deletion and extent tree writes, I see a drop of about 50 pcercent with the current kernel crc32c implementation; this improves to a drop of about 20 percent with the enclosed crc32c code. When metadata is usually a small fraction of total IO, this new implementation doesn't help much because metadata is usually a small fraction of total IO. However, when we are doing IO that is almost all metadata (such as rm -rf'ing a tree), then this patch speeds up the operation substantially. Incidentally, given that iscsi, sctp, and btrfs also use crc32c, this patchset should improve their speed as well. I have not yet quantified that, however. This latest submission combines Bob's patches from late August 2011 with mine so that they can be one coherent patch set. Please excuse my inability to combine some of the patches; I've been advised to leave Bob's patches alone and build atop them instead. :/ Since the last posting, I've also collected some crc32c test results on a bunch of different x86/powerpc/sparc platforms. The results can be viewed here: http://goo.gl/sgt3i ; the "crc32-kern-le" and "crc32c" columns describe the performance of the kernel's current crc32 and crc32c software implementations. The "crc32c-by8-le" column shows crc32c performance with this patchset applied. I expect crc32 performance to be roughly the same. The two _boost columns at the right side of the spreadsheet shows how much faster the new implementation is over the old one. As you can see, crc32 rises substantially, and crc32c experiences a huge increase. This patch: - remove trailing whitespace from lib/crc32.c - remove trailing whitespace from lib/crc32defs.h [djwong@us.ibm.com: changelog tweaks] Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23prio_tree: introduce prio_set_parent()Xiao Guangrong
Introduce prio_set_parent() to abstract the operation which is used to attach the node to its parent. Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23prio_tree: simplify prio_tree_expand()Xiao Guangrong
In current code, the deleted-node is recorded from first to last, actually, we can directly attach these node on 'node' we will insert as the left child, it can let the code more readable. Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-03-23prio_tree: cleanup prio_tree_left()/prio_tree_right()Xiao Guangrong
Introduce iter_walk_down()/iter_walk_up() to remove the common code between prio_tree_left() and prio_tree_right(). Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>