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* Merge tag 'libnvdimm-for-4.5' of ↵Linus Torvalds2016-01-131-0/+39
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm updates from Dan Williams: "The bulk of this has appeared in -next and independently received a build success notification from the kbuild robot. The 'for-4.5/block- dax' topic branch was rebased over the weekend to drop the "block device end-of-life" rework that Al would like to see re-implemented with a notifier, and to address bug reports against the badblocks integration. There is pending feedback against "libnvdimm: Add a poison list and export badblocks" received last week. Linda identified some localized fixups that we will handle incrementally. Summary: - Media error handling: The 'badblocks' implementation that originated in md-raid is up-levelled to a generic capability of a block device. This initial implementation is limited to being consulted in the pmem block-i/o path. Later, 'badblocks' will be consulted when creating dax mappings. - Raw block device dax: For virtualization and other cases that want large contiguous mappings of persistent memory, add the capability to dax-mmap a block device directly. - Increased /dev/mem restrictions: Add an option to treat all io-memory as IORESOURCE_EXCLUSIVE, i.e. disable /dev/mem access while a driver is actively using an address range. This behavior is controlled via the new CONFIG_IO_STRICT_DEVMEM option and can be overridden by the existing "iomem=relaxed" kernel command line option. - Miscellaneous fixes include a 'pfn'-device huge page alignment fix, block device shutdown crash fix, and other small libnvdimm fixes" * tag 'libnvdimm-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (32 commits) block: kill disk_{check|set|clear|alloc}_badblocks libnvdimm, pmem: nvdimm_read_bytes() badblocks support pmem, dax: disable dax in the presence of bad blocks pmem: fail io-requests to known bad blocks libnvdimm: convert to statically allocated badblocks libnvdimm: don't fail init for full badblocks list block, badblocks: introduce devm_init_badblocks block: clarify badblocks lifetime badblocks: rename badblocks_free to badblocks_exit libnvdimm, pmem: move definition of nvdimm_namespace_add_poison to nd.h libnvdimm: Add a poison list and export badblocks nfit_test: Enable DSMs for all test NFITs md: convert to use the generic badblocks code block: Add badblock management for gendisks badblocks: Add core badblock management code block: fix del_gendisk() vs blkdev_ioctl crash block: enable dax for raw block devices block: introduce bdev_file_inode() restrict /dev/mem to idle io memory ranges arch: consolidate CONFIG_STRICT_DEVM in lib/Kconfig.debug ...
| * restrict /dev/mem to idle io memory rangesDan Williams2016-01-091-3/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This effectively promotes IORESOURCE_BUSY to IORESOURCE_EXCLUSIVE semantics by default. If userspace really believes it is safe to access the memory region it can also perform the extra step of disabling an active driver. This protects device address ranges with read side effects and otherwise directs userspace to use the driver. Persistent memory presents a large "mistake surface" to /dev/mem as now accidental writes can corrupt a filesystem. In general if a device driver is busily using a memory region it already informs other parts of the kernel to not touch it via request_mem_region(). /dev/mem should honor the same safety restriction by default. Debugging a device driver from userspace becomes more difficult with this enabled. Any application using /dev/mem or mmap of sysfs pci resources will now need to perform the extra step of either: 1/ Disabling the driver, for example: echo <device id> > /dev/bus/<parent bus>/drivers/<driver name>/unbind 2/ Rebooting with "iomem=relaxed" on the command line 3/ Recompiling with CONFIG_IO_STRICT_DEVMEM=n Traditional users of /dev/mem like dosemu are unaffected because the first 1MB of memory is not subject to the IO_STRICT_DEVMEM restriction. Legacy X configurations use /dev/mem to talk to graphics hardware, but that functionality has since moved to kernel graphics drivers. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Russell King <linux@arm.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Ingo Molnar <mingo@redhat.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * arch: consolidate CONFIG_STRICT_DEVM in lib/Kconfig.debugDan Williams2016-01-091-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Let all the archs that implement devmem_is_allowed() opt-in to a common definition of CONFIG_STRICT_DEVM in lib/Kconfig.debug. Cc: Kees Cook <keescook@chromium.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Will Deacon <will.deacon@arm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "David S. Miller" <davem@davemloft.net> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> [heiko: drop 'default y' for s390] Acked-by: Ingo Molnar <mingo@redhat.com> Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds2016-01-121-0/+23
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking updates from Davic Miller: 1) Support busy polling generically, for all NAPI drivers. From Eric Dumazet. 2) Add byte/packet counter support to nft_ct, from Floriani Westphal. 3) Add RSS/XPS support to mvneta driver, from Gregory Clement. 4) Implement IPV6_HDRINCL socket option for raw sockets, from Hannes Frederic Sowa. 5) Add support for T6 adapter to cxgb4 driver, from Hariprasad Shenai. 6) Add support for VLAN device bridging to mlxsw switch driver, from Ido Schimmel. 7) Add driver for Netronome NFP4000/NFP6000, from Jakub Kicinski. 8) Provide hwmon interface to mlxsw switch driver, from Jiri Pirko. 9) Reorganize wireless drivers into per-vendor directories just like we do for ethernet drivers. From Kalle Valo. 10) Provide a way for administrators "destroy" connected sockets via the SOCK_DESTROY socket netlink diag operation. From Lorenzo Colitti. 11) Add support to add/remove multicast routes via netlink, from Nikolay Aleksandrov. 12) Make TCP keepalive settings per-namespace, from Nikolay Borisov. 13) Add forwarding and packet duplication facilities to nf_tables, from Pablo Neira Ayuso. 14) Dead route support in MPLS, from Roopa Prabhu. 15) TSO support for thunderx chips, from Sunil Goutham. 16) Add driver for IBM's System i/p VNIC protocol, from Thomas Falcon. 17) Rationalize, consolidate, and more completely document the checksum offloading facilities in the networking stack. From Tom Herbert. 18) Support aborting an ongoing scan in mac80211/cfg80211, from Vidyullatha Kanchanapally. 19) Use per-bucket spinlock for bpf hash facility, from Tom Leiming. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1375 commits) net: bnxt: always return values from _bnxt_get_max_rings net: bpf: reject invalid shifts phonet: properly unshare skbs in phonet_rcv() dwc_eth_qos: Fix dma address for multi-fragment skbs phy: remove an unneeded condition mdio: remove an unneed condition mdio_bus: NULL dereference on allocation error net: Fix typo in netdev_intersect_features net: freescale: mac-fec: Fix build error from phy_device API change net: freescale: ucc_geth: Fix build error from phy_device API change bonding: Prevent IPv6 link local address on enslaved devices IB/mlx5: Add flow steering support net/mlx5_core: Export flow steering API net/mlx5_core: Make ipv4/ipv6 location more clear net/mlx5_core: Enable flow steering support for the IB driver net/mlx5_core: Initialize namespaces only when supported by device net/mlx5_core: Set priority attributes net/mlx5_core: Connect flow tables net/mlx5_core: Introduce modify flow table command net/mlx5_core: Managing root flow table ...
| * | net: add support for netdev notifier error injectionNikolay Aleksandrov2015-12-011-0/+23
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This module allows to insert errors in some of netdevice's notifier events. All network drivers use these notifiers to signal various events and to check if they are allowed, e.g. PRECHANGEMTU and CHANGEMTU afterwards. Until recently I had to run failure tests by injecting a custom module, but now this infrastructure makes it trivial to test these failure paths. Some of the recent bugs I fixed were found using this module. Here's an example: $ cd /sys/kernel/debug/notifier-error-inject/netdev $ echo -22 > actions/NETDEV_CHANGEMTU/error $ ip link set eth0 mtu 1024 RTNETLINK answers: Invalid argument CC: Akinobu Mita <akinobu.mita@gmail.com> CC: "David S. Miller" <davem@davemloft.net> CC: netdev <netdev@vger.kernel.org> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge tag 'mmc-v4.5' of git://git.linaro.org/people/ulf.hansson/mmcLinus Torvalds2016-01-111-2/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull MMC updates from Ulf Hansson: "MMC core: - Optimize boot time by detecting cards simultaneously - Make runtime resume default behavior for MMC/SD - Enable MMC/SD/SDIO devices to suspend/resume asynchronously - Allow more than 8 partitions per card - Introduce MMC_CAP2_NO_SDIO to prevent unsupported SDIO commands - Support the standard DT wakeup-source property - Fix driver strength switching for HS200 and HS400 - Fix switch command timeout - Fix invalid vdd in voltage switch power cycle for SDIO MMC host: - sdhci: Restore behavior when setting VDD via external regulator - sdhci: A couple of changes/fixes related to the dma support - sdhci-tegra: Add Tegra210 support - sdhci-tegra: Support for UHS-I cards including tuning support - sdhci-of-at91: Add PM support - sh_mmcif: Rework dma channel handling - mvsdio: Delete platform data code path" * tag 'mmc-v4.5' of git://git.linaro.org/people/ulf.hansson/mmc: (52 commits) mmc: dw_mmc: remove the unused quirks mmc: sdhci-pci: use to_pci_dev() mmc: cb710: use to_platform_device() mmc: tegra: use correct accessor for misc ctrl register mmc: tegra: enable UHS-I modes mmc: tegra: implement UHS tuning mmc: tegra: disable SPI_MODE_CLKEN mmc: tegra: implement module external clock change mmc: sdhci: restore behavior when setting VDD via external regulator mmc: It is not an error for the card to be removed while suspended mmc: block: Allow more than 8 partitions per card mmc: core: Optimize boot time by detecting cards simultaneously mmc: dw_mmc: use resource_size_t to store physical address mmc: core: fix __mmc_switch timeout caused by preempt mmc: usdhi6rol0: handle NULL data in timeout mmc: of_mmc_spi: Add IRQF_ONESHOT to interrupt flags mmc: mediatek: change some dev_err to dev_dbg mmc: enable MMC/SD/SDIO device to suspend/resume asynchronously mmc: sdhci: Fix sdhci_runtime_pm_bus_on/off() mmc: sdhci: 64-bit DMA actually has 4-byte alignment ...
| * | mmc: kconfig: replace FAULT_INJECTION with FAULT_INJECTION_DEBUG_FSAdrien Schildknecht2015-12-221-2/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | Fault-injection capability for MMC IO uses debugfs entries to configure the attributes. FAULT_INJECTION_DEBUG_FS must be enabled to use FAIL_MMC_REQUEST. Replace FAULT_INJECTION with FAULT_INJECTION_DEBUG_FS. Also remove 'select DEBUG_FS' since FAULT_INJECTION_DEBUG_FS depends on it. Signed-off-by: Adrien Schildknecht <adrien+dev@schischi.me> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
* / workqueue: implement lockup detectorTejun Heo2015-12-081-0/+11
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Workqueue stalls can happen from a variety of usage bugs such as missing WQ_MEM_RECLAIM flag or concurrency managed work item indefinitely staying RUNNING. These stalls can be extremely difficult to hunt down because the usual warning mechanisms can't detect workqueue stalls and the internal state is pretty opaque. To alleviate the situation, this patch implements workqueue lockup detector. It periodically monitors all worker_pools periodically and, if any pool failed to make forward progress longer than the threshold duration, triggers warning and dumps workqueue state as follows. BUG: workqueue lockup - pool cpus=0 node=0 flags=0x0 nice=0 stuck for 31s! Showing busy workqueues and worker pools: workqueue events: flags=0x0 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=17/256 pending: monkey_wrench_fn, e1000_watchdog, cache_reap, vmstat_shepherd, release_one_tty, release_one_tty, release_one_tty, release_one_tty, release_one_tty, release_one_tty, release_one_tty, release_one_tty, release_one_tty, release_one_tty, release_one_tty, release_one_tty, cgroup_release_agent workqueue events_power_efficient: flags=0x80 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=2/256 pending: check_lifetime, neigh_periodic_work workqueue cgroup_pidlist_destroy: flags=0x0 pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/1 pending: cgroup_pidlist_destroy_work_fn ... The detection mechanism is controller through kernel parameter workqueue.watchdog_thresh and can be updated at runtime through the sysfs module parameter file. v2: Decoupled from softlockup control knobs. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Don Zickus <dzickus@redhat.com> Cc: Ulrich Obergfell <uobergfe@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Chris Mason <clm@fb.com> Cc: Andrew Morton <akpm@linux-foundation.org>
* Merge tag 'modules-next-for-linus' of ↵Linus Torvalds2015-11-091-0/+9
|\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module updates from Rusty Russell: "Nothing exciting, minor tweaks and cleanups" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: scripts: [modpost] add new sections to white list modpost: Add flag -E for making section mismatches fatal params: don't ignore the rest of cmdline if parse_one() fails modpost: abort if a module symbol is too long
| * modpost: Add flag -E for making section mismatches fatalNicolas Boichat2015-10-061-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The section mismatch warning can be easy to miss during the kernel build process. Allow it to be marked as fatal to be easily caught and prevent bugs from slipping in. Setting CONFIG_SECTION_MISMATCH_WARN_ONLY=y causes these warnings to be non-fatal, since there are a number of section mismatches when using allmodconfig on some architectures, and we do not want to break these builds by default. Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> Change-Id: Ic346706e3297c9f0d790e3552aa94e5cff9897a6 Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | test_printf: test printf family at runtimeRasmus Villemoes2015-11-061-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a simple module for testing the kernel's printf facilities. Previously, some %p extensions have caused a wrong return value in case the entire output didn't fit and/or been unusable in kasprintf(). This should help catch such issues. Also, it should help ensure that changes to the formatting algorithms don't break anything. I'm not sure if we have a struct dentry or struct file lying around at boot time or if we can fake one, but most %p extensions should be testable, as should the ordinary number and string formatting. The nature of vararg functions means we can't use a more conventional table-driven approach. For now, this is mostly a skeleton; contributions are very welcome. Some tests are/will be slightly annoying to write, since the expected output depends on stuff like CONFIG_*, sizeof(long), runtime values etc. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Martin Kletzander <mkletzan@redhat.com> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | lib/Kconfig.debug: disable -Wframe-larger-than warnings with KASAN=yAndrey Ryabinin2015-10-231-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the kernel compiled with KASAN=y, GCC adds redzones for each variable on stack. This enlarges function's stack frame and causes: 'warning: the frame size of X bytes is larger than Y bytes' The worst case I've seen for now is following: ../net/wireless/nl80211.c: In function `nl80211_send_wiphy': ../net/wireless/nl80211.c:1731:1: warning: the frame size of 5448 bytes is larger than 2048 bytes [-Wframe-larger-than=] That kind of warning becomes useless with KASAN=y. It doesn't necessarily indicate that there is some problem in the code, thus we should turn it off. (The KASAN=y stack size in increased from 16k to 32k for this reason) Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Reported-by: Fengguang Wu <fengguang.wu@intel.com> Acked-by: Abylay Ospan <aospan@netup.ru> Cc: Andi Kleen <andi@firstfloor.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Mauro Carvalho Chehab <m.chehab@samsung.com> Cc: Kozlov Sergey <serjk@netup.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'locking-core-for-linus' of ↵Linus Torvalds2015-09-031-6/+16
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking and atomic updates from Ingo Molnar: "Main changes in this cycle are: - Extend atomic primitives with coherent logic op primitives (atomic_{or,and,xor}()) and deprecate the old partial APIs (atomic_{set,clear}_mask()) The old ops were incoherent with incompatible signatures across architectures and with incomplete support. Now every architecture supports the primitives consistently (by Peter Zijlstra) - Generic support for 'relaxed atomics': - _acquire/release/relaxed() flavours of xchg(), cmpxchg() and {add,sub}_return() - atomic_read_acquire() - atomic_set_release() This came out of porting qwrlock code to arm64 (by Will Deacon) - Clean up the fragile static_key APIs that were causing repeat bugs, by introducing a new one: DEFINE_STATIC_KEY_TRUE(name); DEFINE_STATIC_KEY_FALSE(name); which define a key of different types with an initial true/false value. Then allow: static_branch_likely() static_branch_unlikely() to take a key of either type and emit the right instruction for the case. To be able to know the 'type' of the static key we encode it in the jump entry (by Peter Zijlstra) - Static key self-tests (by Jason Baron) - qrwlock optimizations (by Waiman Long) - small futex enhancements (by Davidlohr Bueso) - ... and misc other changes" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits) jump_label/x86: Work around asm build bug on older/backported GCCs locking, ARM, atomics: Define our SMP atomics in terms of _relaxed() operations locking, include/llist: Use linux/atomic.h instead of asm/cmpxchg.h locking/qrwlock: Make use of _{acquire|release|relaxed}() atomics locking/qrwlock: Implement queue_write_unlock() using smp_store_release() locking/lockref: Remove homebrew cmpxchg64_relaxed() macro definition locking, asm-generic: Add _{relaxed|acquire|release}() variants for 'atomic_long_t' locking, asm-generic: Rework atomic-long.h to avoid bulk code duplication locking/atomics: Add _{acquire|release|relaxed}() variants of some atomic operations locking, compiler.h: Cast away attributes in the WRITE_ONCE() magic locking/static_keys: Make verify_keys() static jump label, locking/static_keys: Update docs locking/static_keys: Provide a selftest jump_label: Provide a self-test s390/uaccess, locking/static_keys: employ static_branch_likely() x86, tsc, locking/static_keys: Employ static_branch_likely() locking/static_keys: Add selftest locking/static_keys: Add a new static_key interface locking/static_keys: Rework update logic locking/static_keys: Add static_key_{en,dis}able() helpers ...
| * | locking/static_keys: Provide a selftestIngo Molnar2015-08-031-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The 'jump label' self-test is in reality testing static keys - rename things accordingly. Also prettify the code in various places while at it. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jason Baron <jbaron@akamai.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Shuah Khan <shuahkh@osg.samsung.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: benh@kernel.crashing.org Cc: bp@alien8.de Cc: davem@davemloft.net Cc: ddaney@caviumnetworks.com Cc: heiko.carstens@de.ibm.com Cc: linux-kernel@vger.kernel.org Cc: liuj97@gmail.com Cc: luto@amacapital.net Cc: michael@ellerman.id.au Cc: rabin@rab.in Cc: ralf@linux-mips.org Cc: rostedt@goodmis.org Cc: vbabka@suse.cz Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/0c091ecebd78a879ed8a71835d205a691a75ab4e.1438227999.git.jbaron@akamai.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | jump_label: Provide a self-testJason Baron2015-08-031-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> 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: benh@kernel.crashing.org Cc: bp@alien8.de Cc: davem@davemloft.net Cc: ddaney@caviumnetworks.com Cc: heiko.carstens@de.ibm.com Cc: linux-kernel@vger.kernel.org Cc: liuj97@gmail.com Cc: luto@amacapital.net Cc: michael@ellerman.id.au Cc: rabin@rab.in Cc: ralf@linux-mips.org Cc: rostedt@goodmis.org Cc: shuahkh@osg.samsung.com Cc: vbabka@suse.cz Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/0c091ecebd78a879ed8a71835d205a691a75ab4e.1438227999.git.jbaron@akamai.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | rtmutex: Delete scriptable testerDavidlohr Bueso2015-07-201-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No one uses this anymore, and this is not the first time the idea of replacing it with a (now possible) userspace side. Lock stealing logic was removed long ago in when the lock was granted to the highest prio. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Darren Hart <dvhart@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mike Galbraith <umgwanakikbuti@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1435782588-4177-2-git-send-email-dave@stgolabs.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * | futex: Fault/error injection capabilitiesDavidlohr Bueso2015-07-201-0/+7
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Although futexes are well known for being a royal pita, we really have very little debugging capabilities - except for relying on tglx's eye half the time. By simply making use of the existing fault-injection machinery, we can improve this situation, allowing generating artificial uaddress faults and deadlock scenarios. Of course, when this is disabled in production systems, the overhead for failure checks is practically zero -- so this is very cheap at the same time. Future work would be nice to now enhance trinity to make use of this. There is a special tunable 'ignore-private', which can filter out private futexes. Given the tsk->make_it_fail filter and this option, pi futexes can be narrowed down pretty closely. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Darren Hart <darren@dvhart.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Link: http://lkml.kernel.org/r/1435645562-975-3-git-send-email-dave@stgolabs.net Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | Merge branches 'fixes.2015.07.22a' and 'initexp.2015.08.04a' into HEADPaul E. McKenney2015-08-041-14/+0
|\ \ | | | | | | | | | | | | | | | fixes.2015.07.22a: Miscellaneous fixes. initexp.2015.08.04a: Initialization and expedited updates. (Single branch due to conflicts.)
| * | rcu: Remove CONFIG_RCU_CPU_STALL_INFOPaul E. McKenney2015-07-171-14/+0
| |/ | | | | | | | | | | | | | | | | The CONFIG_RCU_CPU_STALL_INFO has been default-y for a couple of releases with no complaints, so it is time to eliminate this Kconfig option entirely, so that the long-form RCU CPU stall warnings cannot be disabled. This commit does just that. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* / rcu: Clarify CONFIG_RCU_EQS_DEBUG help textPaul E. McKenney2015-07-221-1/+1
|/ | | | | Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* sched/stat: Simplify the sched_info accounting dependencyNaveen N. Rao2015-07-041-0/+5
| | | | | | | | | | | | | | | | | | | Both CONFIG_SCHEDSTATS=y and CONFIG_TASK_DELAY_ACCT=y track task sched_info, which results in ugly #if clauses. Simplify the code by introducing a synthethic CONFIG_SCHED_INFO switch, selected by both. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: a.p.zijlstra@chello.nl Cc: ricklind@us.ibm.com Link: http://lkml.kernel.org/r/8d19eef800811a94b0f91bcbeb27430a884d7433.1435255405.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* rcu: Conditionally compile RCU's eqs warningsPaul E. McKenney2015-05-271-0/+11
| | | | | | | | | | This commit applies some warning-omission micro-optimizations to RCU's various extended-quiescent-state functions, which are on the kernel/user hotpath for CONFIG_NO_HZ_FULL=y. Reported-by: Rik van Riel <riel@redhat.com> Reported by: Mike Galbraith <umgwanakikbuti@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* rcu: Directly drive TASKS_RCU from KconfigPaul E. McKenney2015-05-271-0/+1
| | | | | | | | | | | | | | Currently, Kconfig will ask the user whether TASKS_RCU should be set. This is silly because Kconfig already has all the information that it needs to set this parameter. This commit therefore directly drives the value of TASKS_RCU via "select" statements. Which means that as subsystems require TASKS_RCU, those subsystems will need to add "select" statements of their own. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Steven Rostedt <rostedt@goodmis.org> Reviewed-by: Pranith Kumar <bobby.prani@gmail.com>
* rcu: Provide diagnostic option to slow down grace-period scansPaul E. McKenney2015-05-271-2/+52
| | | | | | | | | | | | | | | | | | Grace-period scans of the rcu_node combining tree normally proceed quite quickly, so that it is very difficult to reproduce races against them. This commit therefore allows grace-period pre-initialization and cleanup to be artificially slowed down, increasing race-reproduction probability. A pair of pairs of new Kconfig parameters are provided, RCU_TORTURE_TEST_SLOW_PREINIT to enable the slowing down of propagating CPU-hotplug changes up the combining tree along with RCU_TORTURE_TEST_SLOW_PREINIT_DELAY to specify the delay in jiffies, and RCU_TORTURE_TEST_SLOW_CLEANUP to enable the slowing down of the end-of-grace-period cleanup scan along with RCU_TORTURE_TEST_SLOW_CLEANUP_DELAY to specify the delay in jiffies. Boot-time parameters named rcutree.gp_preinit_delay and rcutree.gp_cleanup_delay allow these delays to be specified at boot time. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds2015-05-061-0/+1
|\ | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU fix from Ingo Molnar: "An RCU Kconfig fix that eliminates an annoying interactive kconfig question for CONFIG_RCU_TORTURE_TEST_SLOW_INIT" * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: rcu: Control grace-period delays directly from value
| * Merge branch 'for-mingo' of ↵Ingo Molnar2015-04-181-0/+1
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent Pull RCU fix from Paul E. McKenney: "This series contains a single change that fixes Kconfig asking pointless questions." Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * rcu: Control grace-period delays directly from valuePaul E. McKenney2015-04-141-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In a misguided attempt to avoid an #ifdef, the use of the gp_init_delay module parameter was conditioned on the corresponding RCU_TORTURE_TEST_SLOW_INIT Kconfig variable, using IS_ENABLED() at the point of use in the code. This meant that the compiler always saw the delay, which meant that RCU_TORTURE_TEST_SLOW_INIT_DELAY had to be unconditionally defined. This in turn caused "make oldconfig" to ask pointless questions about the value of RCU_TORTURE_TEST_SLOW_INIT_DELAY in cases where it was not even used. This commit avoids these pointless questions by defining gp_init_delay under #ifdef. In one branch, gp_init_delay is initialized to RCU_TORTURE_TEST_SLOW_INIT_DELAY and is also a module parameter (thus allowing boot-time modification), and in the other branch gp_init_delay is a const variable initialized by default to zero. This approach also simplifies the code at the delay point by eliminating the IS_DEFINED(). Because gp_init_delay is constant zero in the no-delay case intended for production use, the "gp_init_delay > 0" check causes the delay to become dead code, as desired in this case. In addition, this commit replaces magic constant "10" with the preprocessor variable PER_RCU_NODE_PERIOD, which controls the number of grace periods that are allowed to elapse at full speed before a delay is inserted. Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* | | Merge branch 'akpm' (patches from Andrew)Linus Torvalds2015-04-141-0/+12
|\ \ \ | |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge first patchbomb from Andrew Morton: - arch/sh updates - ocfs2 updates - kernel/watchdog feature - about half of mm/ * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (122 commits) Documentation: update arch list in the 'memtest' entry Kconfig: memtest: update number of test patterns up to 17 arm: add support for memtest arm64: add support for memtest memtest: use phys_addr_t for physical addresses mm: move memtest under mm mm, hugetlb: abort __get_user_pages if current has been oom killed mm, mempool: do not allow atomic resizing memcg: print cgroup information when system panics due to panic_on_oom mm: numa: remove migrate_ratelimited mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE mm: split ET_DYN ASLR from mmap ASLR s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE mm: expose arch_mmap_rnd when available s390: standardize mmap_rnd() usage powerpc: standardize mmap_rnd() usage mips: extract logic for mmap_rnd() arm64: standardize mmap_rnd() usage x86: standardize mmap_rnd() usage arm: factor out mmap ASLR into mmap_rnd ...
| * | Kconfig: memtest: update number of test patterns up to 17Vladimir Murzin2015-04-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Additional test patterns for memtest were introduced since commit 63823126c221 ("x86: memtest: add additional (regular) test patterns"), but looks like Kconfig was not updated that time. Update Kconfig entry with the actual number of maximum test patterns. Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | mm: move memtest under mmVladimir Murzin2015-04-141-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Memtest is a simple feature which fills the memory with a given set of patterns and validates memory contents, if bad memory regions is detected it reserves them via memblock API. Since memblock API is widely used by other architectures this feature can be enabled outside of x86 world. This patch set promotes memtest to live under generic mm umbrella and enables memtest feature for arm/arm64. It was reported that this patch set was useful for tracking down an issue with some errant DMA on an arm64 platform. This patch (of 6): There is nothing platform dependent in the core memtest code, so other platforms might benefit from this feature too. [linux@roeck-us.net: MEMTEST depends on MEMBLOCK] Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds2015-04-141-10/+25
|\ \ \ | |/ / |/| / | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU changes from Ingo Molnar: "The main changes in this cycle were: - changes permitting use of call_rcu() and friends very early in boot, for example, before rcu_init() is invoked. - add in-kernel API to enable and disable expediting of normal RCU grace periods. - improve RCU's handling of (hotplug-) outgoing CPUs. - NO_HZ_FULL_SYSIDLE fixes. - tiny-RCU updates to make it more tiny. - documentation updates. - miscellaneous fixes" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits) cpu: Provide smpboot_thread_init() on !CONFIG_SMP kernels as well cpu: Defer smpboot kthread unparking until CPU known to scheduler rcu: Associate quiescent-state reports with grace period rcu: Yet another fix for preemption and CPU hotplug rcu: Add diagnostics to grace-period cleanup rcutorture: Default to grace-period-initialization delays rcu: Handle outgoing CPUs on exit from idle loop cpu: Make CPU-offline idle-loop transition point more precise rcu: Eliminate ->onoff_mutex from rcu_node structure rcu: Process offlining and onlining only at grace-period start rcu: Move rcu_report_unblock_qs_rnp() to common code rcu: Rework preemptible expedited bitmask handling rcu: Remove event tracing from rcu_cpu_notify(), used by offline CPUs rcutorture: Enable slow grace-period initializations rcu: Provide diagnostic option to slow down grace-period initialization rcu: Detect stalls caused by failure to propagate up rcu_node tree rcu: Eliminate empty HOTPLUG_CPU ifdef rcu: Simplify sync_rcu_preempt_exp_init() rcu: Put all orphan-callback-related code under same comment rcu: Consolidate offline-CPU callback initialization ...
| *-. Merge branches 'doc.2015.02.26a', 'earlycb.2015.03.03a', ↵Paul E. McKenney2015-03-201-10/+25
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'fixes.2015.03.03a', 'gpexp.2015.02.26a', 'hotplug.2015.03.20a', 'sysidle.2015.02.26b' and 'tiny.2015.02.26a' into HEAD doc.2015.02.26a: Documentation changes earlycb.2015.03.03a: Permit early-boot RCU callbacks fixes.2015.03.03a: Miscellaneous fixes gpexp.2015.02.26a: In-kernel expediting of normal grace periods hotplug.2015.03.20a: CPU hotplug fixes sysidle.2015.02.26b: NO_HZ_FULL_SYSIDLE fixes tiny.2015.02.26a: TINY_RCU fixes
| | | * rcutorture: Default to grace-period-initialization delaysPaul E. McKenney2015-03-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Given that CPU-hotplug events are now applied only at the starts of grace periods, it makes sense to unconditionally enable slow grace-period initialization for rcutorture testing. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| | | * rcu: Provide diagnostic option to slow down grace-period initializationPaul E. McKenney2015-03-111-0/+24
| | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Grace-period initialization normally proceeds quite quickly, so that it is very difficult to reproduce races against grace-period initialization. This commit therefore allows grace-period initialization to be artificially slowed down, increasing race-reproduction probability. A pair of new Kconfig parameters are provided, CONFIG_RCU_TORTURE_TEST_SLOW_INIT to enable the slowdowns, and CONFIG_RCU_TORTURE_TEST_SLOW_INIT_DELAY to specify the number of jiffies of slowdown to apply. A boot-time parameter named rcutree.gp_init_delay allows boot-time delay to be specified. By default, no delay will be applied even if CONFIG_RCU_TORTURE_TEST_SLOW_INIT is set. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| | * rcu: Drive PROVE_RCU directly off of PROVE_LOCKINGPaul E. McKenney2015-02-261-10/+1
| |/ | | | | | | | | | | | | | | | | In the past, it has been useful to enable PROVE_LOCKING without also enabling PROVE_RCU. However, experience with PROVE_RCU over the past few years has demonstrated its usefulness, so this commit makes PROVE_LOCKING directly imply PROVE_RCU. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* / timekeeping: Add debugging checks to warn if we see delaysJohn Stultz2015-03-131-0/+13
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Recently there's been requests for better sanity checking in the time code, so that it's more clear when something is going wrong, since timekeeping issues could manifest in a large number of strange ways in various subsystems. Thus, this patch adds some extra infrastructure to add a check to update_wall_time() to print two new warnings: 1) if we see the call delayed beyond the 'max_cycles' overflow point, 2) or if we see the call delayed beyond the clocksource's 'max_idle_ns' value, which is currently 50% of the overflow point. This extra infrastructure is conditional on a new CONFIG_DEBUG_TIMEKEEPING option, also added in this patch - default off. Tested this a bit by halting qemu for specified lengths of time to trigger the warnings. Signed-off-by: John Stultz <john.stultz@linaro.org> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1426133800-29329-5-git-send-email-john.stultz@linaro.org [ Improved the changelog and the messages a bit. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
* scripts/gdb: add infrastructureJan Kiszka2015-02-171-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This provides the basic infrastructure to load kernel-specific python helper scripts when debugging the kernel in gdb. The loading mechanism is based on gdb loading for <objfile>-gdb.py when opening <objfile>. Therefore, this places a corresponding link to the main helper script into the output directory that contains vmlinux. The main scripts will pull in submodules containing Linux specific gdb commands and functions. To avoid polluting the source directory with compiled python modules, we link to them from the object directory. Due to gdb.parse_and_eval and string redirection for gdb.execute, we depend on gdb >= 7.2. This feature is enabled via CONFIG_GDB_SCRIPTS. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Acked-by: Michal Marek <mmarek@suse.cz> [kbuild stuff] Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Ben Widawsky <ben@bwidawsk.net> Cc: Borislav Petkov <bp@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kasan: add kernel address sanitizer infrastructureAndrey Ryabinin2015-02-131-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Kernel Address sanitizer (KASan) is a dynamic memory error detector. It provides fast and comprehensive solution for finding use-after-free and out-of-bounds bugs. KASAN uses compile-time instrumentation for checking every memory access, therefore GCC > v4.9.2 required. v4.9.2 almost works, but has issues with putting symbol aliases into the wrong section, which breaks kasan instrumentation of globals. This patch only adds infrastructure for kernel address sanitizer. It's not available for use yet. The idea and some code was borrowed from [1]. Basic idea: The main idea of KASAN is to use shadow memory to record whether each byte of memory is safe to access or not, and use compiler's instrumentation to check the shadow memory on each memory access. Address sanitizer uses 1/8 of the memory addressable in kernel for shadow memory and uses direct mapping with a scale and offset to translate a memory address to its corresponding shadow address. Here is function to translate address to corresponding shadow address: unsigned long kasan_mem_to_shadow(unsigned long addr) { return (addr >> KASAN_SHADOW_SCALE_SHIFT) + KASAN_SHADOW_OFFSET; } where KASAN_SHADOW_SCALE_SHIFT = 3. So for every 8 bytes there is one corresponding byte of shadow memory. The following encoding used for each shadow byte: 0 means that all 8 bytes of the corresponding memory region are valid for access; k (1 <= k <= 7) means that the first k bytes are valid for access, and other (8 - k) bytes are not; Any negative value indicates that the entire 8-bytes are inaccessible. Different negative values used to distinguish between different kinds of inaccessible memory (redzones, freed memory) (see mm/kasan/kasan.h). To be able to detect accesses to bad memory we need a special compiler. Such compiler inserts a specific function calls (__asan_load*(addr), __asan_store*(addr)) before each memory access of size 1, 2, 4, 8 or 16. These functions check whether memory region is valid to access or not by checking corresponding shadow memory. If access is not valid an error printed. Historical background of the address sanitizer from Dmitry Vyukov: "We've developed the set of tools, AddressSanitizer (Asan), ThreadSanitizer and MemorySanitizer, for user space. We actively use them for testing inside of Google (continuous testing, fuzzing, running prod services). To date the tools have found more than 10'000 scary bugs in Chromium, Google internal codebase and various open-source projects (Firefox, OpenSSL, gcc, clang, ffmpeg, MySQL and lots of others): [2] [3] [4]. The tools are part of both gcc and clang compilers. We have not yet done massive testing under the Kernel AddressSanitizer (it's kind of chicken and egg problem, you need it to be upstream to start applying it extensively). To date it has found about 50 bugs. Bugs that we've found in upstream kernel are listed in [5]. We've also found ~20 bugs in out internal version of the kernel. Also people from Samsung and Oracle have found some. [...] As others noted, the main feature of AddressSanitizer is its performance due to inline compiler instrumentation and simple linear shadow memory. User-space Asan has ~2x slowdown on computational programs and ~2x memory consumption increase. Taking into account that kernel usually consumes only small fraction of CPU and memory when running real user-space programs, I would expect that kernel Asan will have ~10-30% slowdown and similar memory consumption increase (when we finish all tuning). I agree that Asan can well replace kmemcheck. We have plans to start working on Kernel MemorySanitizer that finds uses of unitialized memory. Asan+Msan will provide feature-parity with kmemcheck. As others noted, Asan will unlikely replace debug slab and pagealloc that can be enabled at runtime. Asan uses compiler instrumentation, so even if it is disabled, it still incurs visible overheads. Asan technology is easily portable to other architectures. Compiler instrumentation is fully portable. Runtime has some arch-dependent parts like shadow mapping and atomic operation interception. They are relatively easy to port." Comparison with other debugging features: ======================================== KMEMCHECK: - KASan can do almost everything that kmemcheck can. KASan uses compile-time instrumentation, which makes it significantly faster than kmemcheck. The only advantage of kmemcheck over KASan is detection of uninitialized memory reads. Some brief performance testing showed that kasan could be x500-x600 times faster than kmemcheck: $ netperf -l 30 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to localhost (127.0.0.1) port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec no debug: 87380 16384 16384 30.00 41624.72 kasan inline: 87380 16384 16384 30.00 12870.54 kasan outline: 87380 16384 16384 30.00 10586.39 kmemcheck: 87380 16384 16384 30.03 20.23 - Also kmemcheck couldn't work on several CPUs. It always sets number of CPUs to 1. KASan doesn't have such limitation. DEBUG_PAGEALLOC: - KASan is slower than DEBUG_PAGEALLOC, but KASan works on sub-page granularity level, so it able to find more bugs. SLUB_DEBUG (poisoning, redzones): - SLUB_DEBUG has lower overhead than KASan. - SLUB_DEBUG in most cases are not able to detect bad reads, KASan able to detect both reads and writes. - In some cases (e.g. redzone overwritten) SLUB_DEBUG detect bugs only on allocation/freeing of object. KASan catch bugs right before it will happen, so we always know exact place of first bad read/write. [1] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel [2] https://code.google.com/p/address-sanitizer/wiki/FoundBugs [3] https://code.google.com/p/thread-sanitizer/wiki/FoundBugs [4] https://code.google.com/p/memory-sanitizer/wiki/FoundBugs [5] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel#Trophies Based on work by Andrey Konovalov. Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com> Acked-by: Michal Marek <mmarek@suse.cz> Signed-off-by: Andrey Konovalov <adech.fo@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Konstantin Serebryany <kcc@google.com> Cc: Dmitry Chernenkov <dmitryc@google.com> Cc: Yuri Gribov <tetra2005@gmail.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Christoph Lameter <cl@linux.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* hexdump: introduce test suiteAndy Shevchenko2015-02-121-0/+3
| | | | | | | | | | | Test different scenarios of function calls located in lib/hexdump.c. Currently hex_dump_to_buffer() is only tested and test data is provided for little endian CPUs. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds2015-02-101-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking updates from David Miller: 1) More iov_iter conversion work from Al Viro. [ The "crypto: switch af_alg_make_sg() to iov_iter" commit was wrong, and this pull actually adds an extra commit on top of the branch I'm pulling to fix that up, so that the pre-merge state is ok. - Linus ] 2) Various optimizations to the ipv4 forwarding information base trie lookup implementation. From Alexander Duyck. 3) Remove sock_iocb altogether, from CHristoph Hellwig. 4) Allow congestion control algorithm selection via routing metrics. From Daniel Borkmann. 5) Make ipv4 uncached route list per-cpu, from Eric Dumazet. 6) Handle rfs hash collisions more gracefully, also from Eric Dumazet. 7) Add xmit_more support to r8169, e1000, and e1000e drivers. From Florian Westphal. 8) Transparent Ethernet Bridging support for GRO, from Jesse Gross. 9) Add BPF packet actions to packet scheduler, from Jiri Pirko. 10) Add support for uniqu flow IDs to openvswitch, from Joe Stringer. 11) New NetCP ethernet driver, from Muralidharan Karicheri and Wingman Kwok. 12) More sanely handle out-of-window dupacks, which can result in serious ACK storms. From Neal Cardwell. 13) Various rhashtable bug fixes and enhancements, from Herbert Xu, Patrick McHardy, and Thomas Graf. 14) Support xmit_more in be2net, from Sathya Perla. 15) Group Policy extensions for vxlan, from Thomas Graf. 16) Remove Checksum Offload support for vxlan, from Tom Herbert. 17) Like ipv4, support lockless transmit over ipv6 UDP sockets. From Vlad Yasevich. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1494+1 commits) crypto: fix af_alg_make_sg() conversion to iov_iter ipv4: Namespecify TCP PMTU mechanism i40e: Fix for stats init function call in Rx setup tcp: don't include Fast Open option in SYN-ACK on pure SYN-data openvswitch: Only set TUNNEL_VXLAN_OPT if VXLAN-GBP metadata is set ipv6: Make __ipv6_select_ident static ipv6: Fix fragment id assignment on LE arches. bridge: Fix inability to add non-vlan fdb entry net: Mellanox: Delete unnecessary checks before the function call "vunmap" cxgb4: Add support in cxgb4 to get expansion rom version via ethtool ethtool: rename reserved1 memeber in ethtool_drvinfo for expansion ROM version net: dsa: Remove redundant phy_attach() IB/mlx4: Reset flow support for IB kernel ULPs IB/mlx4: Always use the correct port for mirrored multicast attachments net/bonding: Fix potential bad memory access during bonding events tipc: remove tipc_snprintf tipc: nl compat add noop and remove legacy nl framework tipc: convert legacy nl stats show to nl compat tipc: convert legacy nl net id get to nl compat tipc: convert legacy nl net id set to nl compat ...
| * rhashtable: Make selftest modularGeert Uytterhoeven2015-01-301-1/+1
| | | | | | | | | | | | | | | | | | Allow the selftest on the resizable hash table to be built modular, just like all other tests that do not depend on DEBUG_KERNEL. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge branch 'for-linus' of ↵Linus Torvalds2015-02-101-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial Pull trivial tree changes from Jiri Kosina: "Patches from trivial.git that keep the world turning around. Mostly documentation and comment fixes, and a two corner-case code fixes from Alan Cox" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: kexec, Kconfig: spell "architecture" properly mm: fix cleancache debugfs directory path blackfin: mach-common: ints-priority: remove unused function doubletalk: probe failure causes OOPS ARM: cache-l2x0.c: Make it clear that cache-l2x0 handles L310 cache controller msdos_fs.h: fix 'fields' in comment scsi: aic7xxx: fix comment ARM: l2c: fix comment ibmraid: fix writeable attribute with no store method dynamic_debug: fix comment doc: usbmon: fix spelling s/unpriviledged/unprivileged/ x86: init_mem_mapping(): use capital BIOS in comment
| * | kexec, Kconfig: spell "architecture" properlyBorislav Petkov2015-01-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | Grepping for "archicture" showed it actually twice! Most unusual spelling error, very interesting. :) Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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*-. \ \ Merge branches 'doc.2015.01.07a', 'fixes.2015.01.15a', ↵Paul E. McKenney2015-01-151-1/+2
|\ \ \ \ | |_|_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'preempt.2015.01.06a', 'srcu.2015.01.06a', 'stall.2015.01.16a' and 'torture.2015.01.11a' into HEAD doc.2015.01.07a: Documentation updates. fixes.2015.01.15a: Miscellaneous fixes. preempt.2015.01.06a: Changes to handling of lists of preempted tasks. srcu.2015.01.06a: SRCU updates. stall.2015.01.16a: RCU CPU stall-warning updates and fixes. torture.2015.01.11a: RCU torture-test updates and fixes.
| | * | rcu: Set default to RCU_CPU_STALL_INFO=yPaul E. McKenney2015-01-061-1/+1
| |/ / |/| | | | | | | | | | | | | | | | | The RCU_CPU_STALL_INFO code has been in for quite some time, and has proven reliable. This commit therefore enables it by default. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| * | rcu: Make SRCU optional by using CONFIG_SRCUPranith Kumar2015-01-061-0/+1
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SRCU is not necessary to be compiled by default in all cases. For tinification efforts not compiling SRCU unless necessary is desirable. The current patch tries to make compiling SRCU optional by introducing a new Kconfig option CONFIG_SRCU which is selected when any of the components making use of SRCU are selected. If we do not select CONFIG_SRCU, srcu.o will not be compiled at all. text data bss dec hex filename 2007 0 0 2007 7d7 kernel/rcu/srcu.o Size of arch/powerpc/boot/zImage changes from text data bss dec hex filename 831552 64180 23944 919676 e087c arch/powerpc/boot/zImage : before 829504 64180 23952 917636 e0084 arch/powerpc/boot/zImage : after so the savings are about ~2000 bytes. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com> CC: Josh Triplett <josh@joshtriplett.org> CC: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> [ paulmck: resolve conflict due to removal of arch/ia64/kvm/Kconfig. ]
* | mm/page_owner: keep track of page ownersJoonsoo Kim2014-12-131-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is the page owner tracking code which is introduced so far ago. It is resident on Andrew's tree, though, nobody tried to upstream so it remain as is. Our company uses this feature actively to debug memory leak or to find a memory hogger so I decide to upstream this feature. This functionality help us to know who allocates the page. When allocating a page, we store some information about allocation in extra memory. Later, if we need to know status of all pages, we can get and analyze it from this stored information. In previous version of this feature, extra memory is statically defined in struct page, but, in this version, extra memory is allocated outside of struct page. It enables us to turn on/off this feature at boottime without considerable memory waste. Although we already have tracepoint for tracing page allocation/free, using it to analyze page owner is rather complex. We need to enlarge the trace buffer for preventing overlapping until userspace program launched. And, launched program continually dump out the trace buffer for later analysis and it would change system behaviour with more possibility rather than just keeping it in memory, so bad for debug. Moreover, we can use page_owner feature further for various purposes. For example, we can use it for fragmentation statistics implemented in this patch. And, I also plan to implement some CMA failure debugging feature using this interface. I'd like to give the credit for all developers contributed this feature, but, it's not easy because I don't know exact history. Sorry about that. Below is people who has "Signed-off-by" in the patches in Andrew's tree. Contributor: Alexander Nyberg <alexn@dsv.su.se> Mel Gorman <mgorman@suse.de> Dave Hansen <dave@linux.vnet.ibm.com> Minchan Kim <minchan@kernel.org> Michal Nazarewicz <mina86@mina86.com> Andrew Morton <akpm@linux-foundation.org> Jungsoo Son <jungsoo.son@lge.com> Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dave Hansen <dave@sr71.net> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Jungsoo Son <jungsoo.son@lge.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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*-. \ Merge branches 'torture.2014.11.03a', 'cpu.2014.11.03a', 'doc.2014.11.13a', ↵Paul E. McKenney2014-11-131-13/+1
|\ \ \ | |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | 'fixes.2014.11.13a', 'signal.2014.10.29a' and 'rt.2014.10.29a' into HEAD cpu.2014.11.03a: Changes for per-CPU variables. doc.2014.11.13a: Documentation updates. fixes.2014.11.13a: Miscellaneous fixes. signal.2014.10.29a: Signal changes. rt.2014.10.29a: Real-time changes. torture.2014.11.03a: torture-test changes.
| | * rcu: Remove redundant TREE_PREEMPT_RCU config optionPranith Kumar2014-10-291-1/+1
| |/ |/| | | | | | | | | | | | | | | PREEMPT_RCU and TREE_PREEMPT_RCU serve the same function after TINY_PREEMPT_RCU has been removed. This patch removes TREE_PREEMPT_RCU and uses PREEMPT_RCU config option in its place. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
| * rcu: Remove CONFIG_RCU_CPU_STALL_VERBOSEPaul E. McKenney2014-10-281-12/+0
|/ | | | | | | | | | | The CONFIG_RCU_CPU_STALL_VERBOSE Kconfig parameter causes preemptible RCU's CPU stall warnings to dump out any preempted tasks that are blocking the current RCU grace period. This information is useful, and the default has been CONFIG_RCU_CPU_STALL_VERBOSE=y for some years. It is therefore time for this commit to remove this Kconfig parameter, so that future kernel builds will always act as if CONFIG_RCU_CPU_STALL_VERBOSE=y. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
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