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2016-07-30Merge branch 'x86-microcode-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 microcode updates from Thomas Gleixner: - more work to make the microcode loader robust - a fix for the micro code load precedence - fixes for initrd loading with randomized memory - less printk noise on SMP machines * 'x86-microcode-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/asm, x86/microcode: Add __PAGE_OFFSET_BASE define on 32-bit x86/microcode/intel: Fix initrd loading with CONFIG_RANDOMIZE_MEMORY=y x86/microcode: Remove unused symbol exports x86/microcode/intel: Do not issue microcode updates messages on each CPU Documentation/microcode: Document some aspects for more clarity x86/microcode/AMD: Make amd_ucode_patch[] static x86/microcode/intel: Unexport save_mc_for_early() x86/microcode/intel: Rename load_microcode_early() to find_microcode_patch() x86/microcode: Propagate save_microcode_in_initrd() retval x86/microcode: Get rid of find_cpio_data()'s dummy offset arg lib/cpio: Make find_cpio_data()'s offset arg optional x86/microcode: Fix suspend to RAM with builtin microcode x86/microcode: Fix loading precedence
2016-07-28Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge more updates from Andrew Morton: "The rest of MM" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (101 commits) mm, compaction: simplify contended compaction handling mm, compaction: introduce direct compaction priority mm, thp: remove __GFP_NORETRY from khugepaged and madvised allocations mm, page_alloc: make THP-specific decisions more generic mm, page_alloc: restructure direct compaction handling in slowpath mm, page_alloc: don't retry initial attempt in slowpath mm, page_alloc: set alloc_flags only once in slowpath lib/stackdepot.c: use __GFP_NOWARN for stack allocations mm, kasan: switch SLUB to stackdepot, enable memory quarantine for SLUB mm, kasan: account for object redzone in SLUB's nearest_obj() mm: fix use-after-free if memory allocation failed in vma_adjust() zsmalloc: Delete an unnecessary check before the function call "iput" mm/memblock.c: fix index adjustment error in __next_mem_range_rev() mem-hotplug: alloc new page from a nearest neighbor node when mem-offline mm: optimize copy_page_to/from_iter_iovec mm: add cond_resched() to generic_swapfile_activate() Revert "mm, mempool: only set __GFP_NOMEMALLOC if there are free elements" mm, compaction: don't isolate PageWriteback pages in MIGRATE_SYNC_LIGHT mode mm: hwpoison: remove incorrect comments make __section_nr() more efficient ...
2016-07-28lib/stackdepot.c: use __GFP_NOWARN for stack allocationsKirill A. Shutemov
This (large, atomic) allocation attempt can fail. We expect and handle that, so avoid the scary warning. Link: http://lkml.kernel.org/r/20160720151905.GB19146@node.shutemov.name Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Rik van Riel <riel@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28mm, kasan: switch SLUB to stackdepot, enable memory quarantine for SLUBAlexander Potapenko
For KASAN builds: - switch SLUB allocator to using stackdepot instead of storing the allocation/deallocation stacks in the objects; - change the freelist hook so that parts of the freelist can be put into the quarantine. [aryabinin@virtuozzo.com: fixes] Link: http://lkml.kernel.org/r/1468601423-28676-1-git-send-email-aryabinin@virtuozzo.com Link: http://lkml.kernel.org/r/1468347165-41906-3-git-send-email-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <adech.fo@gmail.com> Cc: Christoph Lameter <cl@linux.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Steven Rostedt (Red Hat) <rostedt@goodmis.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kostya Serebryany <kcc@google.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Kuthonuzo Luruo <kuthonuzo.luruo@hpe.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28mm: optimize copy_page_to/from_iter_iovecMikulas Patocka
copy_page_to_iter_iovec() and copy_page_from_iter_iovec() copy some data to userspace or from userspace. These functions have a fast path where they map a page using kmap_atomic and a slow path where they use kmap. kmap is slower than kmap_atomic, so the fast path is preferred. However, on kernels without highmem support, kmap just calls page_address, so there is no need to avoid kmap. On kernels without highmem support, the fast path just increases code size (and cache footprint) and it doesn't improve copy performance in any way. This patch enables the fast path only if CONFIG_HIGHMEM is defined. Code size reduced by this patch: x86 (without highmem) 928 x86-64 960 sparc64 848 alpha 1136 pa-risc 1200 [akpm@linux-foundation.org: use IS_ENABLED(), per Andi] Link: http://lkml.kernel.org/r/alpine.LRH.2.02.1607221711410.4818@file01.intranet.prod.int.rdu2.redhat.com Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28Merge branch 'salted-string-hash'Linus Torvalds
This changes the vfs dentry hashing to mix in the parent pointer at the _beginning_ of the hash, rather than at the end. That actually improves both the hash and the code generation, because we can move more of the computation to the "static" part of the dcache setup, and do less at lookup runtime. It turns out that a lot of other hash users also really wanted to mix in a base pointer as a 'salt' for the hash, and so the slightly extended interface ends up working well for other cases too. Users that want a string hash that is purely about the string pass in a 'salt' pointer of NULL. * merge branch 'salted-string-hash': fs/dcache.c: Save one 32-bit multiply in dcache lookup vfs: make the string hashes salt the hash
2016-07-27Merge tag 'random_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random Pull random driver updates from Ted Ts'o: "A number of improvements for the /dev/random driver; the most important is the use of a ChaCha20-based CRNG for /dev/urandom, which is faster, more efficient, and easier to make scalable for silly/abusive userspace programs that want to read from /dev/urandom in a tight loop on NUMA systems. This set of patches also improves entropy gathering on VM's running on Microsoft Azure, and will take advantage of a hw random number generator (if present) to initialize the /dev/urandom pool" (It turns out that the random tree hadn't been in linux-next this time around, because it had been dropped earlier as being too quiet. Oh well). * tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: random: strengthen input validation for RNDADDTOENTCNT random: add backtracking protection to the CRNG random: make /dev/urandom scalable for silly userspace programs random: replace non-blocking pool with a Chacha20-based CRNG random: properly align get_random_int_hash random: add interrupt callback to VMBus IRQ handler random: print a warning for the first ten uninitialized random users random: initialize the non-blocking pool via add_hwgenerator_randomness()
2016-07-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
Pull networking updates from David Miller: 1) Unified UDP encapsulation offload methods for drivers, from Alexander Duyck. 2) Make DSA binding more sane, from Andrew Lunn. 3) Support QCA9888 chips in ath10k, from Anilkumar Kolli. 4) Several workqueue usage cleanups, from Bhaktipriya Shridhar. 5) Add XDP (eXpress Data Path), essentially running BPF programs on RX packets as soon as the device sees them, with the option to mirror the packet on TX via the same interface. From Brenden Blanco and others. 6) Allow qdisc/class stats dumps to run lockless, from Eric Dumazet. 7) Add VLAN support to b53 and bcm_sf2, from Florian Fainelli. 8) Simplify netlink conntrack entry layout, from Florian Westphal. 9) Add ipv4 forwarding support to mlxsw spectrum driver, from Ido Schimmel, Yotam Gigi, and Jiri Pirko. 10) Add SKB array infrastructure and convert tun and macvtap over to it. From Michael S Tsirkin and Jason Wang. 11) Support qdisc packet injection in pktgen, from John Fastabend. 12) Add neighbour monitoring framework to TIPC, from Jon Paul Maloy. 13) Add NV congestion control support to TCP, from Lawrence Brakmo. 14) Add GSO support to SCTP, from Marcelo Ricardo Leitner. 15) Allow GRO and RPS to function on macsec devices, from Paolo Abeni. 16) Support MPLS over IPV4, from Simon Horman. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1622 commits) xgene: Fix build warning with ACPI disabled. be2net: perform temperature query in adapter regardless of its interface state l2tp: Correctly return -EBADF from pppol2tp_getname. net/mlx5_core/health: Remove deprecated create_singlethread_workqueue net: ipmr/ip6mr: update lastuse on entry change macsec: ensure rx_sa is set when validation is disabled tipc: dump monitor attributes tipc: add a function to get the bearer name tipc: get monitor threshold for the cluster tipc: make cluster size threshold for monitoring configurable tipc: introduce constants for tipc address validation net: neigh: disallow transition to NUD_STALE if lladdr is unchanged in neigh_update() MAINTAINERS: xgene: Add driver and documentation path Documentation: dtb: xgene: Add MDIO node dtb: xgene: Add MDIO node drivers: net: xgene: ethtool: Use phy_ethtool_gset and sset drivers: net: xgene: Use exported functions drivers: net: xgene: Enable MDIO driver drivers: net: xgene: Add backward compatibility drivers: net: phy: xgene: Add MDIO driver ...
2016-07-27Merge branch 'linus' into x86/microcode, to pick up merge window changesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-26Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge updates from Andrew Morton: - a few misc bits - ocfs2 - most(?) of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (125 commits) thp: fix comments of __pmd_trans_huge_lock() cgroup: remove unnecessary 0 check from css_from_id() cgroup: fix idr leak for the first cgroup root mm: memcontrol: fix documentation for compound parameter mm: memcontrol: remove BUG_ON in uncharge_list mm: fix build warnings in <linux/compaction.h> mm, thp: convert from optimistic swapin collapsing to conservative mm, thp: fix comment inconsistency for swapin readahead functions thp: update Documentation/{vm/transhuge,filesystems/proc}.txt shmem: split huge pages beyond i_size under memory pressure thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE khugepaged: add support of collapse for tmpfs/shmem pages shmem: make shmem_inode_info::lock irq-safe khugepaged: move up_read(mmap_sem) out of khugepaged_alloc_page() thp: extract khugepaged from mm/huge_memory.c shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings shmem: add huge pages support shmem: get_unmapped_area align huge page shmem: prepare huge= mount option and sysfs knob mm, rmap: account shmem thp pages ...
2016-07-26radix-tree: implement radix_tree_maybe_preload_order()Kirill A. Shutemov
The new helper is similar to radix_tree_maybe_preload(), but tries to preload number of nodes required to insert (1 << order) continuous naturally-aligned elements. This is required to push huge pages into pagecache. Link: http://lkml.kernel.org/r/1466021202-61880-24-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26mm/page_owner: use stackdepot to store stacktraceJoonsoo Kim
Currently, we store each page's allocation stacktrace on corresponding page_ext structure and it requires a lot of memory. This causes the problem that memory tight system doesn't work well if page_owner is enabled. Moreover, even with this large memory consumption, we cannot get full stacktrace because we allocate memory at boot time and just maintain 8 stacktrace slots to balance memory consumption. We could increase it to more but it would make system unusable or change system behaviour. To solve the problem, this patch uses stackdepot to store stacktrace. It obviously provides memory saving but there is a drawback that stackdepot could fail. stackdepot allocates memory at runtime so it could fail if system has not enough memory. But, most of allocation stack are generated at very early time and there are much memory at this time. So, failure would not happen easily. And, one failure means that we miss just one page's allocation stacktrace so it would not be a big problem. In this patch, when memory allocation failure happens, we store special stracktrace handle to the page that is failed to save stacktrace. With it, user can guess memory usage properly even if failure happens. Memory saving looks as following. (4GB memory system with page_owner) (before the patch -> after the patch) static allocation: 92274688 bytes -> 25165824 bytes dynamic allocation after boot + kernel build: 0 bytes -> 327680 bytes total: 92274688 bytes -> 25493504 bytes 72% reduction in total. Note that implementation looks complex than someone would imagine because there is recursion issue. stackdepot uses page allocator and page_owner is called at page allocation. Using stackdepot in page_owner could re-call page allcator and then page_owner. That is a recursion. To detect and avoid it, whenever we obtain stacktrace, recursion is checked and page_owner is set to dummy information if found. Dummy information means that this page is allocated for page_owner feature itself (such as stackdepot) and it's understandable behavior for user. [iamjoonsoo.kim@lge.com: mm-page_owner-use-stackdepot-to-store-stacktrace-v3] Link: http://lkml.kernel.org/r/1464230275-25791-6-git-send-email-iamjoonsoo.kim@lge.com Link: http://lkml.kernel.org/r/1466150259-27727-7-git-send-email-iamjoonsoo.kim@lge.com Link: http://lkml.kernel.org/r/1464230275-25791-6-git-send-email-iamjoonsoo.kim@lge.com Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Minchan Kim <minchan@kernel.org> Cc: Alexander Potapenko <glider@google.com> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26dma-debug: track bucket lock state for static checkersStephen Boyd
get_hash_bucket() and put_hash_bucket() acquire and release the same spinlock, but this confuses static checkers such as sparse lib/dma-debug.c:254:27: warning: context imbalance in 'get_hash_bucket' - wrong count at exit lib/dma-debug.c:268:13: warning: context imbalance in 'put_hash_bucket' - unexpected unlock Add the appropriate acquire and release statements so that checkers can properly track the lock state. Link: http://lkml.kernel.org/r/20160701191552.24295-1-sboyd@codeaurora.org Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26Merge branch 'for-4.8/core' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull core block updates from Jens Axboe: - the big change is the cleanup from Mike Christie, cleaning up our uses of command types and modified flags. This is what will throw some merge conflicts - regression fix for the above for btrfs, from Vincent - following up to the above, better packing of struct request from Christoph - a 2038 fix for blktrace from Arnd - a few trivial/spelling fixes from Bart Van Assche - a front merge check fix from Damien, which could cause issues on SMR drives - Atari partition fix from Gabriel - convert cfq to highres timers, since jiffies isn't granular enough for some devices these days. From Jan and Jeff - CFQ priority boost fix idle classes, from me - cleanup series from Ming, improving our bio/bvec iteration - a direct issue fix for blk-mq from Omar - fix for plug merging not involving the IO scheduler, like we do for other types of merges. From Tahsin - expose DAX type internally and through sysfs. From Toshi and Yigal * 'for-4.8/core' of git://git.kernel.dk/linux-block: (76 commits) block: Fix front merge check block: do not merge requests without consulting with io scheduler block: Fix spelling in a source code comment block: expose QUEUE_FLAG_DAX in sysfs block: add QUEUE_FLAG_DAX for devices to advertise their DAX support Btrfs: fix comparison in __btrfs_map_block() block: atari: Return early for unsupported sector size Doc: block: Fix a typo in queue-sysfs.txt cfq-iosched: Charge at least 1 jiffie instead of 1 ns cfq-iosched: Fix regression in bonnie++ rewrite performance cfq-iosched: Convert slice_resid from u64 to s64 block: Convert fifo_time from ulong to u64 blktrace: avoid using timespec block/blk-cgroup.c: Declare local symbols static block/bio-integrity.c: Add #include "blk.h" block/partition-generic.c: Remove a set-but-not-used variable block: bio: kill BIO_MAX_SIZE cfq-iosched: temporarily boost queue priority for idle classes block: drbd: avoid to use BIO_MAX_SIZE block: bio: remove BIO_MAX_SECTORS ...
2016-07-26Merge branch 'linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "Here is the crypto update for 4.8: API: - first part of skcipher low-level conversions - add KPP (Key-agreement Protocol Primitives) interface. Algorithms: - fix IPsec/cryptd reordering issues that affects aesni - RSA no longer does explicit leading zero removal - add SHA3 - add DH - add ECDH - improve DRBG performance by not doing CTR by hand Drivers: - add x86 AVX2 multibuffer SHA256/512 - add POWER8 optimised crc32c - add xts support to vmx - add DH support to qat - add RSA support to caam - add Layerscape support to caam - add SEC1 AEAD support to talitos - improve performance by chaining requests in marvell/cesa - add support for Araneus Alea I USB RNG - add support for Broadcom BCM5301 RNG - add support for Amlogic Meson RNG - add support Broadcom NSP SoC RNG" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (180 commits) crypto: vmx - Fix aes_p8_xts_decrypt build failure crypto: vmx - Ignore generated files crypto: vmx - Adding support for XTS crypto: vmx - Adding asm subroutines for XTS crypto: skcipher - add comment for skcipher_alg->base crypto: testmgr - Print akcipher algorithm name crypto: marvell - Fix wrong flag used for GFP in mv_cesa_dma_add_iv_op crypto: nx - off by one bug in nx_of_update_msc() crypto: rsa-pkcs1pad - fix rsa-pkcs1pad request struct crypto: scatterwalk - Inline start/map/done crypto: scatterwalk - Remove unnecessary BUG in scatterwalk_start crypto: scatterwalk - Remove unnecessary advance in scatterwalk_pagedone crypto: scatterwalk - Fix test in scatterwalk_done crypto: api - Optimise away crypto_yield when hard preemption is on crypto: scatterwalk - add no-copy support to copychunks crypto: scatterwalk - Remove scatterwalk_bytes_sglen crypto: omap - Stop using crypto scatterwalk_bytes_sglen crypto: skcipher - Remove top-level givcipher interface crypto: user - Remove crypto_lookup_skcipher call crypto: cts - Convert to skcipher ...
2016-07-25Merge branch 'timers-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "This update provides the following changes: - The rework of the timer wheel which addresses the shortcomings of the current wheel (cascading, slow search for next expiring timer, etc). That's the first major change of the wheel in almost 20 years since Finn implemted it. - A large overhaul of the clocksource drivers init functions to consolidate the Device Tree initialization - Some more Y2038 updates - A capability fix for timerfd - Yet another clock chip driver - The usual pile of updates, comment improvements all over the place" * 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (130 commits) tick/nohz: Optimize nohz idle enter clockevents: Make clockevents_subsys static clocksource/drivers/time-armada-370-xp: Fix return value check timers: Implement optimization for same expiry time in mod_timer() timers: Split out index calculation timers: Only wake softirq if necessary timers: Forward the wheel clock whenever possible timers/nohz: Remove pointless tick_nohz_kick_tick() function timers: Optimize collect_expired_timers() for NOHZ timers: Move __run_timers() function timers: Remove set_timer_slack() leftovers timers: Switch to a non-cascading wheel timers: Reduce the CPU index space to 256k timers: Give a few structs and members proper names hlist: Add hlist_is_singular_node() helper signals: Use hrtimer for sigtimedwait() timers: Remove the deprecated mod_timer_pinned() API timers, net/ipv4/inet: Initialize connection request timers as pinned timers, drivers/tty/mips_ejtag: Initialize the poll timer as pinned timers, drivers/tty/metag_da: Initialize the poll timer as pinned ...
2016-07-25Merge branch 'x86-mm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 mm updates from Ingo Molnar: "Various x86 low level modifications: - preparatory work to support virtually mapped kernel stacks (Andy Lutomirski) - support for 64-bit __get_user() on 32-bit kernels (Benjamin LaHaise) - (involved) workaround for Knights Landing CPU erratum (Dave Hansen) - MPX enhancements (Dave Hansen) - mremap() extension to allow remapping of the special VDSO vma, for purposes of user level context save/restore (Dmitry Safonov) - hweight and entry code cleanups (Borislav Petkov) - bitops code generation optimizations and cleanups with modern GCC (H. Peter Anvin) - syscall entry code optimizations (Paolo Bonzini)" * 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (43 commits) x86/mm/cpa: Add missing comment in populate_pdg() x86/mm/cpa: Fix populate_pgd(): Stop trying to deallocate failed PUDs x86/syscalls: Add compat_sys_preadv64v2/compat_sys_pwritev64v2 x86/smp: Remove unnecessary initialization of thread_info::cpu x86/smp: Remove stack_smp_processor_id() x86/uaccess: Move thread_info::addr_limit to thread_struct x86/dumpstack: Rename thread_struct::sig_on_uaccess_error to sig_on_uaccess_err x86/uaccess: Move thread_info::uaccess_err and thread_info::sig_on_uaccess_err to thread_struct x86/dumpstack: When OOPSing, rewind the stack before do_exit() x86/mm/64: In vmalloc_fault(), use CR3 instead of current->active_mm x86/dumpstack/64: Handle faults when printing the "Stack: " part of an OOPS x86/dumpstack: Try harder to get a call trace on stack overflow x86/mm: Remove kernel_unmap_pages_in_pgd() and efi_cleanup_page_tables() x86/mm/cpa: In populate_pgd(), don't set the PGD entry until it's populated x86/mm/hotplug: Don't remove PGD entries in remove_pagetable() x86/mm: Use pte_none() to test for empty PTE x86/mm: Disallow running with 32-bit PTEs to work around erratum x86/mm: Ignore A/D bits in pte/pmd/pud_none() x86/mm: Move swap offset/type up in PTE to work around erratum x86/entry: Inline enter_from_user_mode() ...
2016-07-25Merge branch 'locking-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: "The locking tree was busier in this cycle than the usual pattern - a couple of major projects happened to coincide. The main changes are: - implement the atomic_fetch_{add,sub,and,or,xor}() API natively across all SMP architectures (Peter Zijlstra) - add atomic_fetch_{inc/dec}() as well, using the generic primitives (Davidlohr Bueso) - optimize various aspects of rwsems (Jason Low, Davidlohr Bueso, Waiman Long) - optimize smp_cond_load_acquire() on arm64 and implement LSE based atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() on arm64 (Will Deacon) - introduce smp_acquire__after_ctrl_dep() and fix various barrier mis-uses and bugs (Peter Zijlstra) - after discovering ancient spin_unlock_wait() barrier bugs in its implementation and usage, strengthen its semantics and update/fix usage sites (Peter Zijlstra) - optimize mutex_trylock() fastpath (Peter Zijlstra) - ... misc fixes and cleanups" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits) locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire() locking/static_keys: Fix non static symbol Sparse warning locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec() locking/atomic, arch/tile: Fix tilepro build locking/atomic, arch/m68k: Remove comment locking/atomic, arch/arc: Fix build locking/Documentation: Clarify limited control-dependency scope locking/atomic, arch/rwsem: Employ atomic_long_fetch_add() locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire() locking/atomic, arch/mips: Convert to _relaxed atomics locking/atomic, arch/alpha: Convert to _relaxed atomics locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions locking/atomic: Remove linux/atomic.h:atomic_fetch_or() locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() locking/atomic: Fix atomic64_relaxed() bits locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}() locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() ...
2016-07-15x86/uaccess: Move thread_info::addr_limit to thread_structAndy Lutomirski
struct thread_info is a legacy mess. To prepare for its partial removal, move thread_info::addr_limit out. As an added benefit, this way is simpler. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/15bee834d09402b47ac86f2feccdf6529f9bc5b0.1468527351.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-07timers: Remove set_timer_slack() leftoversThomas Gleixner
We now have implicit batching in the timer wheel. The slack API is no longer used, so remove it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Andrew F. Davis <afd@ti.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Chris Mason <clm@fb.com> Cc: David S. Miller <davem@davemloft.net> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: George Spelvin <linux@sciencehorizons.net> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jaehoon Chung <jh80.chung@samsung.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: John Stultz <john.stultz@linaro.org> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Len Brown <lenb@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathias Nyman <mathias.nyman@intel.com> Cc: Pali Rohár <pali.rohar@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Sebastian Reichel <sre@kernel.org> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: linux-block@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: linux-mmc@vger.kernel.org Cc: linux-pm@vger.kernel.org Cc: linux-usb@vger.kernel.org Cc: netdev@vger.kernel.org Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160704094342.189813118@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-06Introduce rb_replace_node_rcu()David Howells
Implement an RCU-safe variant of rb_replace_node() and rearrange rb_replace_node() to do things in the same order. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2016-07-03random: replace non-blocking pool with a Chacha20-based CRNGTheodore Ts'o
The CRNG is faster, and we don't pretend to track entropy usage in the CRNG any more. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-07-01lib/mpi: Do not do sg_virtHerbert Xu
Currently the mpi SG helpers use sg_virt which is completely broken. It happens to work with normal kernel memory but will fail with anything that is not linearly mapped. This patch fixes this by using the SG iterator helpers. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-07-01crypto: rsa - Generate fixed-length outputHerbert Xu
Every implementation of RSA that we have naturally generates output with leading zeroes. The one and only user of RSA, pkcs1pad wants to have those leading zeroes in place, in fact because they are currently absent it has to write those zeroes itself. So we shouldn't be stripping leading zeroes in the first place. In fact this patch makes rsa-generic produce output with fixed length so that pkcs1pad does not need to do any extra work. This patch also changes DH to use the new interface. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-06-16locking/atomic: Implement ↵Peter Zijlstra
atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() Now that all the architectures have implemented support for these new atomic primitives add on the generic infrastructure to expose and use it. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Borislav Petkov <bp@suse.de> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arch@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-14torture: Remove CONFIG_RCU_TORTURE_TEST_RUNNABLE, simplify codePaul E. McKenney
This commit removes CONFIG_RCU_TORTURE_TEST_RUNNABLE in favor of the already-existing rcutorture.torture_runnable kernel boot parameter. It also converts an #ifdef into IS_ENABLED(), saving a few lines of code. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-06-14torture: Simplify code, eliminate RCU_PERF_TEST_RUNNABLEPaul E. McKenney
This commit applies the infamous IS_ENABLED() macro to eliminate a #ifdef. It also eliminates the RCU_PERF_TEST_RUNNABLE Kconfig option in favor of the already-existing rcuperf.perf_runnable kernel boot parameter. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-06-10vfs: make the string hashes salt the hashLinus Torvalds
We always mixed in the parent pointer into the dentry name hash, but we did it late at lookup time. It turns out that we can simplify that lookup-time action by salting the hash with the parent pointer early instead of late. A few other users of our string hashes also wanted to mix in their own pointers into the hash, and those are updated to use the same mechanism. Hash users that don't have any particular initial salt can just use the NULL pointer as a no-salt. Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: George Spelvin <linux@sciencehorizons.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-09iov_iter: use bvec iterator to implement iterate_bvec()Ming Lei
bvec has one native/mature iterator for long time, so not necessary to use the reinvented wheel for iterating bvecs in lib/iov_iter.c. Two ITER_BVEC test cases are run: - xfstest(-g auto) on loop dio/aio, no regression found - swap file works well under extreme stress(stress-ng --all 64 -t 800 -v), and lots of OOMs are triggerd, and the whole system still survives Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Ming Lei <ming.lei@canonical.com> Tested-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2016-06-08x86/hweight: Get rid of the special calling conventionBorislav Petkov
People complained about ARCH_HWEIGHT_CFLAGS and how it throws a wrench into kcov, lto, etc, experimentations. Add asm versions for __sw_hweight{32,64}() and do explicit saving and restoring of clobbered registers. This gets rid of the special calling convention. We get to call those functions on !X86_FEATURE_POPCNT CPUs. We still need to hardcode POPCNT and register operands as some old gas versions which we support, do not know about POPCNT. Btw, remove redundant REX prefix from 32-bit POPCNT because alternatives can do padding now. Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1464605787-20603-1-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08lib/cpio: Make find_cpio_data()'s offset arg optionalBorislav Petkov
Some callers don't use it so make it optional. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1465225850-7352-4-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-31lib/mpi: refactor mpi_read_from_buffer() in terms of mpi_read_raw_data()Nicolai Stange
mpi_read_from_buffer() and mpi_read_raw_data() do basically the same thing except that the former extracts the number of payload bits from the first two bytes of the input buffer. Besides that, the data copying logic is exactly the same. Replace the open coded buffer to MPI instance conversion by a call to mpi_read_raw_data(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-31lib/mpi: mpi_read_from_buffer(): sanitize short buffer printkNicolai Stange
The first two bytes of the input buffer encode its expected length and mpi_read_from_buffer() prints a console message if the given buffer is too short. However, there are some oddities with how this message is printed: - It is printed at the default loglevel. This is different from the one used in the case that the first two bytes' value is unsupportedly large, i.e. KERN_INFO. - The format specifier '%d' is used for unsigned ints. - It prints the values of nread and *ret_nread. This is redundant since the former is always the latter + 1. Clean this up as follows: - Use pr_info() rather than printk() with no loglevel. - Use the format specifiers '%u' in place if '%d'. - Do not print the redundant 'nread' but the more helpful 'nbytes' value. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-31lib/mpi: mpi_read_from_buffer(): return -EINVAL upon too short bufferNicolai Stange
Currently, if the input buffer is shorter than the expected length as indicated by its first two bytes, an MPI instance of this expected length will be allocated and filled with as much data as is available. The rest will remain uninitialized. Instead of leaving this condition undetected, an error code should be reported to the caller. Since this situation indicates that the input buffer's first two bytes, encoding the number of expected bits, are garbled, -EINVAL is appropriate here. If the input buffer is shorter than indicated by its first two bytes, make mpi_read_from_buffer() return -EINVAL. Get rid of the 'nread' variable: with the new semantics, the total number of bytes read from the input buffer is known in advance. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-31lib/digsig: digsig_verify_rsa(): return -EINVAL if modulo length is zeroNicolai Stange
Currently, if digsig_verify_rsa() detects that the modulo's length is zero, i.e. mlen == 0, it returns -ENOMEM which doesn't really fit here. Make digsig_verify_rsa() return -EINVAL upon mlen == 0. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-31lib/mpi: mpi_read_from_buffer(): return error codeNicolai Stange
mpi_read_from_buffer() reads a MPI from a buffer into a newly allocated MPI instance. It expects the buffer's leading two bytes to contain the number of bits, followed by the actual payload. On failure, it returns NULL and updates the in/out argument ret_nread somewhat inconsistently: - If the given buffer is too short to contain the leading two bytes encoding the number of bits or their value is unsupported, then ret_nread will be cleared. - If the allocation of the resulting MPI instance fails, ret_nread is left as is. The only user of mpi_read_from_buffer(), digsig_verify_rsa(), simply checks for a return value of NULL and returns -ENOMEM if that happens. While this is all of cosmetic nature only, there is another error condition which currently isn't detectable by the caller of mpi_read_from_buffer(): if the given buffer is too small to hold the number of bits as encoded in its first two bytes, the return value will be non-NULL and *ret_nread > 0. In preparation of communicating this condition to the caller, let mpi_read_from_buffer() return error values by means of the ERR_PTR() mechanism. Make the sole caller of mpi_read_from_buffer(), digsig_verify_rsa(), check the return value for IS_ERR() rather than == NULL. If IS_ERR() is true, return the associated error value rather than the fixed -ENOMEM. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-31lib/mpi: mpi_read_raw_data(): fix nbits calculationNicolai Stange
The number of bits, nbits, is calculated in mpi_read_raw_data() as follows: nbits = nbytes * 8; Afterwards, the number of leading zero bits of the first byte get subtracted: nbits -= count_leading_zeros(buffer[0]); However, count_leading_zeros() takes an unsigned long and thus, the u8 gets promoted to an unsigned long. Thus, the above doesn't subtract the number of leading zeros in the most significant nonzero input byte from nbits, but the number of leading zeros of the most significant nonzero input byte promoted to unsigned long, i.e. BITS_PER_LONG - 8 too many. Fix this by subtracting count_leading_zeros(...) - (BITS_PER_LONG - 8) from nbits only. Fixes: e1045992949 ("MPILIB: Provide a function to read raw data into an MPI") Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-31lib/mpi: mpi_read_raw_data(): purge redundant clearing of nbitsNicolai Stange
In mpi_read_raw_data(), unsigned nbits is calculated as follows: nbits = nbytes * 8; and redundantly cleared later on if nbytes == 0: if (nbytes > 0) ... else nbits = 0; Purge this redundant clearing for the sake of clarity. Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-31lib/mpi: purge mpi_set_buffer()Nicolai Stange
mpi_set_buffer() has no in-tree users and similar functionality is provided by mpi_read_raw_data(). Remove mpi_set_buffer(). Signed-off-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-30lib/uuid.c: use correct offset in uuid parserBjørn Mork
Use '+ 0' and '+ 1' as offsets, like they were intended, instead of adding to the result. Fixes: 2b1b0d66704a ("lib/uuid.c: introduce a few more generic helpers") Signed-off-by: Bjørn Mork <bjorn@mork.no> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-30lib/uuid: add a test moduleAndy Shevchenko
It appears that somehow I missed a test of the latest UUID rework which landed in the kernel. Present a small test module to avoid such cases in the future. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-28Merge branch 'hash' of git://ftp.sciencehorizons.net/linuxLinus Torvalds
Pull string hash improvements from George Spelvin: "This series does several related things: - Makes the dcache hash (fs/namei.c) useful for general kernel use. (Thanks to Bruce for noticing the zero-length corner case) - Converts the string hashes in <linux/sunrpc/svcauth.h> to use the above. - Avoids 64-bit multiplies in hash_64() on 32-bit platforms. Two 32-bit multiplies will do well enough. - Rids the world of the bad hash multipliers in hash_32. This finishes the job started in commit 689de1d6ca95 ("Minimal fix-up of bad hashing behavior of hash_64()") The vast majority of Linux architectures have hardware support for 32x32-bit multiply and so derive no benefit from "simplified" multipliers. The few processors that do not (68000, h8/300 and some models of Microblaze) have arch-specific implementations added. Those patches are last in the series. - Overhauls the dcache hash mixing. The patch in commit 0fed3ac866ea ("namei: Improve hash mixing if CONFIG_DCACHE_WORD_ACCESS") was an off-the-cuff suggestion. Replaced with a much more careful design that's simultaneously faster and better. (My own invention, as there was noting suitable in the literature I could find. Comments welcome!) - Modify the hash_name() loop to skip the initial HASH_MIX(). This would let us salt the hash if we ever wanted to. - Sort out partial_name_hash(). The hash function is declared as using a long state, even though it's truncated to 32 bits at the end and the extra internal state contributes nothing to the result. And some callers do odd things: - fs/hfs/string.c only allocates 32 bits of state - fs/hfsplus/unicode.c uses it to hash 16-bit unicode symbols not bytes - Modify bytemask_from_count to handle inputs of 1..sizeof(long) rather than 0..sizeof(long)-1. This would simplify users other than full_name_hash" Special thanks to Bruce Fields for testing and finding bugs in v1. (I learned some humbling lessons about "obviously correct" code.) On the arch-specific front, the m68k assembly has been tested in a standalone test harness, I've been in contact with the Microblaze maintainers who mostly don't care, as the hardware multiplier is never omitted in real-world applications, and I haven't heard anything from the H8/300 world" * 'hash' of git://ftp.sciencehorizons.net/linux: h8300: Add <asm/hash.h> microblaze: Add <asm/hash.h> m68k: Add <asm/hash.h> <linux/hash.h>: Add support for architecture-specific functions fs/namei.c: Improve dcache hash function Eliminate bad hash multipliers from hash_32() and hash_64() Change hash_64() return value to 32 bits <linux/sunrpc/svcauth.h>: Define hash_str() in terms of hashlen_string() fs/namei.c: Add hashlen_string() function Pull out string hash to <linux/stringhash.h>
2016-05-28<linux/hash.h>: Add support for architecture-specific functionsGeorge Spelvin
This is just the infrastructure; there are no users yet. This is modelled on CONFIG_ARCH_RANDOM; a CONFIG_ symbol declares the existence of <asm/hash.h>. That file may define its own versions of various functions, and define HAVE_* symbols (no CONFIG_ prefix!) to suppress the generic ones. Included is a self-test (in lib/test_hash.c) that verifies the basics. It is NOT in general required that the arch-specific functions compute the same thing as the generic, but if a HAVE_* symbol is defined with the value 1, then equality is tested. Signed-off-by: George Spelvin <linux@sciencehorizons.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Andreas Schwab <schwab@linux-m68k.org> Cc: Philippe De Muyter <phdm@macq.eu> Cc: linux-m68k@lists.linux-m68k.org Cc: Alistair Francis <alistai@xilinx.com> Cc: Michal Simek <michal.simek@xilinx.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: uclinux-h8-devel@lists.sourceforge.jp
2016-05-26dma-debug: avoid spinlock recursion when disabling dma-debugVille Syrjälä
With netconsole (at least) the pr_err("... disablingn") call can recurse back into the dma-debug code, where it'll try to grab free_entries_lock again. Avoid the problem by doing the printk after dropping the lock. Link: http://lkml.kernel.org/r/1463678421-18683-1-git-send-email-ville.syrjala@linux.intel.com Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-25Merge branch 'work.iov_iter' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs iov_iter regression fix from Al Viro: "Fix for braino in 'fold checks into iterate_and_advance()'" * 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: do "fold checks into iterate_and_advance()" right
2016-05-25do "fold checks into iterate_and_advance()" rightAl Viro
the only case when we should skip the iterate_and_advance() guts is when nothing's left in the iterator, _not_ just when requested amount is 0. Said guts will do nothing in the latter case anyway; the problem we tried to deal with in the aforementioned commit is that when there's nothing left *and* the amount requested is 0, we might end up deferencing one iovec too many; the value we fetch from there is discarded in that case, but theoretically it might oops if the iovec array ends exactly at the end of page with the next page not mapped. Bailing out on zero size requested had an unexpected side effect - zero-length segment in the beginning of iovec array ended up throwing do_loop_readv_writev() into infinite spin; we do not advance past the empty segment at all. Reproducer is trivial: echo '#include <sys/uio.h>' >a.c echo 'main() {char c; struct iovec v[] = {{&c,0},{&c,1}}; readv(0,v,2);}' >>a.c cc a.c && ./a.out </proc/uptime which should end up with the process not hanging. Probably ought to go into LTP or xfstests... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-23kgdb: depends on VTJiri Slaby
With VT=n, the kernel build fails with: drivers/built-in.o: In function `kgdboc_pre_exp_handler': kgdboc.c:(.text+0x7b5aa): undefined reference to `fg_console' kgdboc.c:(.text+0x7b5ce): undefined reference to `vc_cons' kgdboc.c:(.text+0x7b5d5): undefined reference to `vc_cons' kgdboc.o is built when KGDB_SERIAL_CONSOLE is set. So make KGDB_SERIAL_CONSOLE depend on HW_CONSOLE which includes those symbols. Link: http://lkml.kernel.org/r/1459412955-4696-1-git-send-email-jslaby@suse.cz Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reported-by: "Jim Davis" <jim.epost@gmail.com> Acked-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge more updates from Andrew Morton: - the rest of MM - KASAN updates - procfs updates - exit, fork updates - printk updates - lib/ updates - radix-tree testsuite updates - checkpatch updates - kprobes updates - a few other misc bits * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (162 commits) samples/kprobes: print out the symbol name for the hooks samples/kprobes: add a new module parameter kprobes: add the "tls" argument for j_do_fork init/main.c: simplify initcall_blacklisted() fs/efs/super.c: fix return value checkpatch: improve --git <commit-count> shortcut checkpatch: reduce number of `git log` calls with --git checkpatch: add support to check already applied git commits checkpatch: add --list-types to show message types to show or ignore checkpatch: advertise the --fix and --fix-inplace options more checkpatch: whine about ACCESS_ONCE checkpatch: add test for keywords not starting on tabstops checkpatch: improve CONSTANT_COMPARISON test for structure members checkpatch: add PREFER_IS_ENABLED test lib/GCD.c: use binary GCD algorithm instead of Euclidean radix-tree: free up the bottom bit of exceptional entries for reuse dax: move RADIX_DAX_ definitions to dax.c radix-tree: make radix_tree_descend() more useful radix-tree: introduce radix_tree_replace_clear_tags() radix-tree: tidy up __radix_tree_create() ...
2016-05-20Merge tag 'driver-core-4.7-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core updates from Greg KH: "Here's the "big" driver core update for 4.7-rc1. Mostly just debugfs changes, the long-known and messy races with removing debugfs files should be fixed thanks to the great work of Nicolai Stange. We also have some isa updates in here (the x86 maintainers told me to take it through this tree), a new warning when we run out of dynamic char major numbers, and a few other assorted changes, details in the shortlog. All have been in linux-next for some time with no reported issues" * tag 'driver-core-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (32 commits) Revert "base: dd: don't remove driver_data in -EPROBE_DEFER case" gpio: ws16c48: Utilize the ISA bus driver gpio: 104-idio-16: Utilize the ISA bus driver gpio: 104-idi-48: Utilize the ISA bus driver gpio: 104-dio-48e: Utilize the ISA bus driver watchdog: ebc-c384_wdt: Utilize the ISA bus driver iio: stx104: Utilize the module_isa_driver and max_num_isa_dev macros iio: stx104: Add X86 dependency to STX104 Kconfig option Documentation: Add ISA bus driver documentation isa: Implement the max_num_isa_dev macro isa: Implement the module_isa_driver macro pnp: pnpbios: Add explicit X86_32 dependency to PNPBIOS isa: Decouple X86_32 dependency from the ISA Kconfig option driver-core: use 'dev' argument in dev_dbg_ratelimited stub base: dd: don't remove driver_data in -EPROBE_DEFER case kernfs: Move faulting copy_user operations outside of the mutex devcoredump: add scatterlist support debugfs: unproxify files created through debugfs_create_u32_array() debugfs: unproxify files created through debugfs_create_blob() debugfs: unproxify files created through debugfs_create_bool() ...
2016-05-20lib/GCD.c: use binary GCD algorithm instead of EuclideanZhaoxiu Zeng
The binary GCD algorithm is based on the following facts: 1. If a and b are all evens, then gcd(a,b) = 2 * gcd(a/2, b/2) 2. If a is even and b is odd, then gcd(a,b) = gcd(a/2, b) 3. If a and b are all odds, then gcd(a,b) = gcd((a-b)/2, b) = gcd((a+b)/2, b) Even on x86 machines with reasonable division hardware, the binary algorithm runs about 25% faster (80% the execution time) than the division-based Euclidian algorithm. On platforms like Alpha and ARMv6 where division is a function call to emulation code, it's even more significant. There are two variants of the code here, depending on whether a fast __ffs (find least significant set bit) instruction is available. This allows the unpredictable branches in the bit-at-a-time shifting loop to be eliminated. If fast __ffs is not available, the "even/odd" GCD variant is used. I use the following code to benchmark: #include <stdio.h> #include <stdlib.h> #include <stdint.h> #include <string.h> #include <time.h> #include <unistd.h> #define swap(a, b) \ do { \ a ^= b; \ b ^= a; \ a ^= b; \ } while (0) unsigned long gcd0(unsigned long a, unsigned long b) { unsigned long r; if (a < b) { swap(a, b); } if (b == 0) return a; while ((r = a % b) != 0) { a = b; b = r; } return b; } unsigned long gcd1(unsigned long a, unsigned long b) { unsigned long r = a | b; if (!a || !b) return r; b >>= __builtin_ctzl(b); for (;;) { a >>= __builtin_ctzl(a); if (a == b) return a << __builtin_ctzl(r); if (a < b) swap(a, b); a -= b; } } unsigned long gcd2(unsigned long a, unsigned long b) { unsigned long r = a | b; if (!a || !b) return r; r &= -r; while (!(b & r)) b >>= 1; for (;;) { while (!(a & r)) a >>= 1; if (a == b) return a; if (a < b) swap(a, b); a -= b; a >>= 1; if (a & r) a += b; a >>= 1; } } unsigned long gcd3(unsigned long a, unsigned long b) { unsigned long r = a | b; if (!a || !b) return r; b >>= __builtin_ctzl(b); if (b == 1) return r & -r; for (;;) { a >>= __builtin_ctzl(a); if (a == 1) return r & -r; if (a == b) return a << __builtin_ctzl(r); if (a < b) swap(a, b); a -= b; } } unsigned long gcd4(unsigned long a, unsigned long b) { unsigned long r = a | b; if (!a || !b) return r; r &= -r; while (!(b & r)) b >>= 1; if (b == r) return r; for (;;) { while (!(a & r)) a >>= 1; if (a == r) return r; if (a == b) return a; if (a < b) swap(a, b); a -= b; a >>= 1; if (a & r) a += b; a >>= 1; } } static unsigned long (*gcd_func[])(unsigned long a, unsigned long b) = { gcd0, gcd1, gcd2, gcd3, gcd4, }; #define TEST_ENTRIES (sizeof(gcd_func) / sizeof(gcd_func[0])) #if defined(__x86_64__) #define rdtscll(val) do { \ unsigned long __a,__d; \ __asm__ __volatile__("rdtsc" : "=a" (__a), "=d" (__d)); \ (val) = ((unsigned long long)__a) | (((unsigned long long)__d)<<32); \ } while(0) static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long), unsigned long a, unsigned long b, unsigned long *res) { unsigned long long start, end; unsigned long long ret; unsigned long gcd_res; rdtscll(start); gcd_res = gcd(a, b); rdtscll(end); if (end >= start) ret = end - start; else ret = ~0ULL - start + 1 + end; *res = gcd_res; return ret; } #else static inline struct timespec read_time(void) { struct timespec time; clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &time); return time; } static inline unsigned long long diff_time(struct timespec start, struct timespec end) { struct timespec temp; if ((end.tv_nsec - start.tv_nsec) < 0) { temp.tv_sec = end.tv_sec - start.tv_sec - 1; temp.tv_nsec = 1000000000ULL + end.tv_nsec - start.tv_nsec; } else { temp.tv_sec = end.tv_sec - start.tv_sec; temp.tv_nsec = end.tv_nsec - start.tv_nsec; } return temp.tv_sec * 1000000000ULL + temp.tv_nsec; } static unsigned long long benchmark_gcd_func(unsigned long (*gcd)(unsigned long, unsigned long), unsigned long a, unsigned long b, unsigned long *res) { struct timespec start, end; unsigned long gcd_res; start = read_time(); gcd_res = gcd(a, b); end = read_time(); *res = gcd_res; return diff_time(start, end); } #endif static inline unsigned long get_rand() { if (sizeof(long) == 8) return (unsigned long)rand() << 32 | rand(); else return rand(); } int main(int argc, char **argv) { unsigned int seed = time(0); int loops = 100; int repeats = 1000; unsigned long (*res)[TEST_ENTRIES]; unsigned long long elapsed[TEST_ENTRIES]; int i, j, k; for (;;) { int opt = getopt(argc, argv, "n:r:s:"); /* End condition always first */ if (opt == -1) break; switch (opt) { case 'n': loops = atoi(optarg); break; case 'r': repeats = atoi(optarg); break; case 's': seed = strtoul(optarg, NULL, 10); break; default: /* You won't actually get here. */ break; } } res = malloc(sizeof(unsigned long) * TEST_ENTRIES * loops); memset(elapsed, 0, sizeof(elapsed)); srand(seed); for (j = 0; j < loops; j++) { unsigned long a = get_rand(); /* Do we have args? */ unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand(); unsigned long long min_elapsed[TEST_ENTRIES]; for (k = 0; k < repeats; k++) { for (i = 0; i < TEST_ENTRIES; i++) { unsigned long long tmp = benchmark_gcd_func(gcd_func[i], a, b, &res[j][i]); if (k == 0 || min_elapsed[i] > tmp) min_elapsed[i] = tmp; } } for (i = 0; i < TEST_ENTRIES; i++) elapsed[i] += min_elapsed[i]; } for (i = 0; i < TEST_ENTRIES; i++) printf("gcd%d: elapsed %llu\n", i, elapsed[i]); k = 0; srand(seed); for (j = 0; j < loops; j++) { unsigned long a = get_rand(); unsigned long b = argc > optind ? strtoul(argv[optind], NULL, 10) : get_rand(); for (i = 1; i < TEST_ENTRIES; i++) { if (res[j][i] != res[j][0]) break; } if (i < TEST_ENTRIES) { if (k == 0) { k = 1; fprintf(stderr, "Error:\n"); } fprintf(stderr, "gcd(%lu, %lu): ", a, b); for (i = 0; i < TEST_ENTRIES; i++) fprintf(stderr, "%ld%s", res[j][i], i < TEST_ENTRIES - 1 ? ", " : "\n"); } } if (k == 0) fprintf(stderr, "PASS\n"); free(res); return 0; } Compiled with "-O2", on "VirtualBox 4.4.0-22-generic #38-Ubuntu x86_64" got: zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10 gcd0: elapsed 10174 gcd1: elapsed 2120 gcd2: elapsed 2902 gcd3: elapsed 2039 gcd4: elapsed 2812 PASS zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10 gcd0: elapsed 9309 gcd1: elapsed 2280 gcd2: elapsed 2822 gcd3: elapsed 2217 gcd4: elapsed 2710 PASS zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10 gcd0: elapsed 9589 gcd1: elapsed 2098 gcd2: elapsed 2815 gcd3: elapsed 2030 gcd4: elapsed 2718 PASS zhaoxiuzeng@zhaoxiuzeng-VirtualBox:~/develop$ ./gcd -r 500000 -n 10 gcd0: elapsed 9914 gcd1: elapsed 2309 gcd2: elapsed 2779 gcd3: elapsed 2228 gcd4: elapsed 2709 PASS [akpm@linux-foundation.org: avoid #defining a CONFIG_ variable] Signed-off-by: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com> Signed-off-by: George Spelvin <linux@horizon.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>