Commit Graph

1399 Commits

Author SHA1 Message Date
Peter Zijlstra 2c61002271 locking/qspinlock: Fix spin_unlock_wait() some more
While this prior commit:

  54cf809b95 ("locking,qspinlock: Fix spin_is_locked() and spin_unlock_wait()")

... fixes spin_is_locked() and spin_unlock_wait() for the usage
in ipc/sem and netfilter, it does not in fact work right for the
usage in task_work and futex.

So while the 2 locks crossed problem:

	spin_lock(A)		spin_lock(B)
	if (!spin_is_locked(B)) spin_unlock_wait(A)
	  foo()			foo();

... works with the smp_mb() injected by both spin_is_locked() and
spin_unlock_wait(), this is not sufficient for:

	flag = 1;
	smp_mb();		spin_lock()
	spin_unlock_wait()	if (!flag)
				  // add to lockless list
	// iterate lockless list

... because in this scenario, the store from spin_lock() can be delayed
past the load of flag, uncrossing the variables and loosing the
guarantee.

This patch reworks spin_is_locked() and spin_unlock_wait() to work in
both cases by exploiting the observation that while the lock byte
store can be delayed, the contender must have registered itself
visibly in other state contained in the word.

It also allows for architectures to override both functions, as PPC
and ARM64 have an additional issue for which we currently have no
generic solution.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Giovanni Gherdovich <ggherdovich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <waiman.long@hpe.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: stable@vger.kernel.org # v4.2 and later
Fixes: 54cf809b95 ("locking,qspinlock: Fix spin_is_locked() and spin_unlock_wait()")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-08 14:29:08 +02:00
Linus Torvalds f89eae4ee7 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Two fixes: one for a lost wakeup, the other to fix the compiler
  optimizing out preempt operations on ARM64 (and possibly other non-x86
  architectures)"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Fix remote wakeups
  sched/preempt: Fix preempt_count manipulations
2016-05-25 17:11:43 -07:00
Peter Zijlstra 54cf809b95 locking,qspinlock: Fix spin_is_locked() and spin_unlock_wait()
Similar to commits:

  51d7d5205d ("powerpc: Add smp_mb() to arch_spin_is_locked()")
  d86b8da04d ("arm64: spinlock: serialise spin_unlock_wait against concurrent lockers")

qspinlock suffers from the fact that the _Q_LOCKED_VAL store is
unordered inside the ACQUIRE of the lock.

And while this is not a problem for the regular mutual exclusive
critical section usage of spinlocks, it breaks creative locking like:

	spin_lock(A)			spin_lock(B)
	spin_unlock_wait(B)		if (!spin_is_locked(A))
	do_something()			  do_something()

In that both CPUs can end up running do_something at the same time,
because our _Q_LOCKED_VAL store can drop past the spin_unlock_wait()
spin_is_locked() loads (even on x86!!).

To avoid making the normal case slower, add smp_mb()s to the less used
spin_unlock_wait() / spin_is_locked() side of things to avoid this
problem.

Reported-and-tested-by: Davidlohr Bueso <dave@stgolabs.net>
Reported-by: Giovanni Gherdovich <ggherdovich@suse.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org   # v4.2 and later
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-20 19:30:32 -07:00
Linus Torvalds a05a70db34 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - fsnotify fix

 - poll() timeout fix

 - a few scripts/ tweaks

 - debugobjects updates

 - the (small) ocfs2 queue

 - Minor fixes to kernel/padata.c

 - Maybe half of the MM queue

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (117 commits)
  mm, page_alloc: restore the original nodemask if the fast path allocation failed
  mm, page_alloc: uninline the bad page part of check_new_page()
  mm, page_alloc: don't duplicate code in free_pcp_prepare
  mm, page_alloc: defer debugging checks of pages allocated from the PCP
  mm, page_alloc: defer debugging checks of freed pages until a PCP drain
  cpuset: use static key better and convert to new API
  mm, page_alloc: inline pageblock lookup in page free fast paths
  mm, page_alloc: remove unnecessary variable from free_pcppages_bulk
  mm, page_alloc: pull out side effects from free_pages_check
  mm, page_alloc: un-inline the bad part of free_pages_check
  mm, page_alloc: check multiple page fields with a single branch
  mm, page_alloc: remove field from alloc_context
  mm, page_alloc: avoid looking up the first zone in a zonelist twice
  mm, page_alloc: shortcut watermark checks for order-0 pages
  mm, page_alloc: reduce cost of fair zone allocation policy retry
  mm, page_alloc: shorten the page allocator fast path
  mm, page_alloc: check once if a zone has isolated pageblocks
  mm, page_alloc: move __GFP_HARDWALL modifications out of the fastpath
  mm, page_alloc: simplify last cpupid reset
  mm, page_alloc: remove unnecessary initialisation from __alloc_pages_nodemask()
  ...
2016-05-19 20:00:06 -07:00
Hugh Dickins fd8cfd3000 arch: fix has_transparent_hugepage()
I've just discovered that the useful-sounding has_transparent_hugepage()
is actually an architecture-dependent minefield: on some arches it only
builds if CONFIG_TRANSPARENT_HUGEPAGE=y, on others it's also there when
not, but on some of those (arm and arm64) it then gives the wrong
answer; and on mips alone it's marked __init, which would crash if
called later (but so far it has not been called later).

Straighten this out: make it available to all configs, with a sensible
default in asm-generic/pgtable.h, removing its definitions from those
arches (arc, arm, arm64, sparc, tile) which are served by the default,
adding #define has_transparent_hugepage has_transparent_hugepage to
those (mips, powerpc, s390, x86) which need to override the default at
runtime, and removing the __init from mips (but maybe that kind of code
should be avoided after init: set a static variable the first time it's
called).

Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Yang Shi <yang.shi@linaro.org>
Cc: Ning Qu <quning@gmail.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Vineet Gupta <vgupta@synopsys.com>		[arch/arc]
Acked-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>	[arch/s390]
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-19 19:12:14 -07:00
Linus Torvalds e0fb1b3639 IOMMU Updates for Linux v4.7
The updates include:
 
 	* Rate limiting for the VT-d fault handler
 
 	* Remove statistics code from the AMD IOMMU driver. It is unused
 	  and should be replaced by something more generic if needed
 
 	* Per-domain pagesize-bitmaps in IOMMU core code to support
 	  systems with different types of IOMMUs
 
 	* Support for ACPI devices in the AMD IOMMU driver
 
 	* 4GB mode support for Mediatek IOMMU driver
 
 	* ARM-SMMU updates from Will Deacon:
 
 		- Support for 64k pages with SMMUv1 implementations
 		  (e.g MMU-401)
 
 		- Remove open-coded 64-bit MMIO accessors
 
 		- Initial support for 16-bit VMIDs, as supported by some
 		  ThunderX SMMU implementations
 
 		- A couple of errata workarounds for silicon in the
 		  field
 
 	* Various fixes here and there
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Merge tag 'iommu-updates-v4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

Pull IOMMU updates from Joerg Roedel:
 "The updates include:

   - rate limiting for the VT-d fault handler

   - remove statistics code from the AMD IOMMU driver.  It is unused and
     should be replaced by something more generic if needed

   - per-domain pagesize-bitmaps in IOMMU core code to support systems
     with different types of IOMMUs

   - support for ACPI devices in the AMD IOMMU driver

   - 4GB mode support for Mediatek IOMMU driver

   - ARM-SMMU updates from Will Deacon:
      - support for 64k pages with SMMUv1 implementations (e.g MMU-401)
      - remove open-coded 64-bit MMIO accessors
      - initial support for 16-bit VMIDs, as supported by some ThunderX
        SMMU implementations
      - a couple of errata workarounds for silicon in the field

   - various fixes here and there"

* tag 'iommu-updates-v4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (44 commits)
  iommu/arm-smmu: Use per-domain page sizes.
  iommu/amd: Remove statistics code
  iommu/dma: Finish optimising higher-order allocations
  iommu: Allow selecting page sizes per domain
  iommu: of: enforce const-ness of struct iommu_ops
  iommu: remove unused priv field from struct iommu_ops
  iommu/dma: Implement scatterlist segment merging
  iommu/arm-smmu: Clear cache lock bit of ACR
  iommu/arm-smmu: Support SMMUv1 64KB supplement
  iommu/arm-smmu: Decouple context format from kernel config
  iommu/arm-smmu: Tidy up 64-bit/atomic I/O accesses
  io-64-nonatomic: Add relaxed accessor variants
  iommu/arm-smmu: Work around MMU-500 prefetch errata
  iommu/arm-smmu: Convert ThunderX workaround to new method
  iommu/arm-smmu: Differentiate specific implementations
  iommu/arm-smmu: Workaround for ThunderX erratum #27704
  iommu/arm-smmu: Add support for 16 bit VMID
  iommu/amd: Move get_device_id() and friends to beginning of file
  iommu/amd: Don't use IS_ERR_VALUE to check integer values
  iommu/amd: Signedness bug in acpihid_device_group()
  ...
2016-05-19 17:07:04 -07:00
Linus Torvalds 07b75260eb Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
 "This is the main pull request for MIPS for 4.7.  Here's the summary of
  the changes:

   - ATH79: Support for DTB passuing using the UHI boot protocol
   - ATH79: Remove support for builtin DTB.
   - ATH79: Add zboot debug serial support.
   - ATH79: Add initial support for Dragino MS14 (Dragine 2), Onion Omega
            and DPT-Module.
   - ATH79: Update devicetree clock support for AR9132 and AR9331.
   - ATH79: Cleanup the DT code.
   - ATH79: Support newer SOCs in ath79_ddr_ctrl_init.
   - ATH79: Fix regression in PCI window initialization.
   - BCM47xx: Move SPROM driver to drivers/firmware/
   - BCM63xx: Enable partition parser in defconfig.
   - BMIPS: BMIPS5000 has I cache filing from D cache
   - BMIPS: BMIPS: Add cpu-feature-overrides.h
   - BMIPS: Add Whirlwind support
   - BMIPS: Adjust mips-hpt-frequency for BCM7435
   - BMIPS: Remove maxcpus from BCM97435SVMB DTS
   - BMIPS: Add missing 7038 L1 register cells to BCM7435
   - BMIPS: Various tweaks to initialization code.
   - BMIPS: Enable partition parser in defconfig.
   - BMIPS: Cache tweaks.
   - BMIPS: Add UART, I2C and SATA devices to DT.
   - BMIPS: Add BCM6358 and BCM63268support
   - BMIPS: Add device tree example for BCM6358.
   - BMIPS: Improve Improve BCM6328 and BCM6368 device trees
   - Lantiq: Add support for device tree file from boot loader
   - Lantiq: Allow build with no built-in DT.
   - Loongson 3: Reserve 32MB for RS780E integrated GPU.
   - Loongson 3: Fix build error after ld-version.sh modification
   - Loongson 3: Move chipset ACPI code from drivers to arch.
   - Loongson 3: Speedup irq processing.
   - Loongson 3: Add basic Loongson 3A support.
   - Loongson 3: Set cache flush handlers to nop.
   - Loongson 3: Invalidate special TLBs when needed.
   - Loongson 3: Fast TLB refill handler.
   - MT7620: Fallback strategy for invalid syscfg0.
   - Netlogic: Fix CP0_EBASE redefinition warnings
   - Octeon: Initialization fixes
   - Octeon: Add DTS files for the D-Link DSR-1000N and EdgeRouter Lite
   - Octeon: Enable add Octeon-drivers in cavium_octeon_defconfig
   - Octeon: Correctly handle endian-swapped initramfs images.
   - Octeon: Support CN73xx, CN75xx and CN78xx.
   - Octeon: Remove dead code from cvmx-sysinfo.
   - Octeon: Extend number of supported CPUs past 32.
   - Octeon: Remove some code limiting NR_IRQS to 255.
   - Octeon: Simplify octeon_irq_ciu_gpio_set_type.
   - Octeon: Mark some functions __init in smp.c
   - Octeon: Octeon: Add Octeon III CN7xxx interface detection
   - PIC32: Add serial driver and bindings for it.
   - PIC32: Add PIC32 deadman timer driver and bindings.
   - PIC32: Add PIC32 clock timer driver and bindings.
   - Pistachio: Determine SoC revision during boot
   - Sibyte: Fix Kconfig dependencies of SIBYTE_BUS_WATCHER.
   - Sibyte: Strip redundant comments from bcm1480_regs.h.
   - Panic immediately if panic_on_oops is set.
   - module: fix incorrect IS_ERR_VALUE macro usage.
   - module: Make consistent use of pr_*
   - Remove no longer needed work_on_cpu() call.
   - Remove CONFIG_IPV6_PRIVACY from defconfigs.
   - Fix registers of non-crashing CPUs in dumps.
   - Handle MIPSisms in new vmcore_elf32_check_arch.
   - Select CONFIG_HANDLE_DOMAIN_IRQ and make it work.
   - Allow RIXI to be used on non-R2 or R6 cores.
   - Reserve nosave data for hibernation
   - Fix siginfo.h to use strict POSIX types.
   - Don't unwind user mode with EVA.
   - Fix watchpoint restoration
   - Ptrace watchpoints for R6.
   - Sync icache when it fills from dcache
   - I6400 I-cache fills from dcache.
   - Various MSA fixes.
   - Cleanup MIPS_CPU_* definitions.
   - Signal: Move generic copy_siginfo to signal.h
   - Signal: Fix uapi include in exported asm/siginfo.h
   - Timer fixes for sake of KVM.
   - XPA TLB refill fixes.
   - Treat perf counter feature
   - Update John Crispin's email address
   - Add PIC32 watchdog and bindings.
   - Handle R10000 LL/SC bug in set_pte()
   - cpufreq: Various fixes for Longson1.
   - R6: Fix R2 emulation.
   - mathemu: Cosmetic fix to ADDIUPC emulation, plenty of other small fixes
   - ELF: ABI and FP fixes.
   - Allow for relocatable kernel and use that to support KASLR.
   - Fix CPC_BASE_ADDR mask
   - Plenty fo smp-cps, CM, R6 and M6250 fixes.
   - Make reset_control_ops const.
   - Fix kernel command line handling of leading whitespace.
   - Cleanups to cache handling.
   - Add brcm, bcm6345-l1-intc device tree bindings.
   - Use generic clkdev.h header
   - Remove CLK_IS_ROOT usage.
   - Misc small cleanups.
   - CM: Fix compilation error when !MIPS_CM
   - oprofile: Fix a preemption issue
   - Detect DSP ASE v3 support:1"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (275 commits)
  MIPS: pic32mzda: fix getting timer clock rate.
  MIPS: ath79: fix regression in PCI window initialization
  MIPS: ath79: make ath79_ddr_ctrl_init() compatible for newer SoCs
  MIPS: Fix VZ probe gas errors with binutils <2.24
  MIPS: perf: Fix I6400 event numbers
  MIPS: DEC: Export `ioasic_ssr_lock' to modules
  MIPS: MSA: Fix a link error on `_init_msa_upper' with older GCC
  MIPS: CM: Fix compilation error when !MIPS_CM
  MIPS: Fix genvdso error on rebuild
  USB: ohci-jz4740: Remove obsolete driver
  MIPS: JZ4740: Probe OHCI platform device via DT
  MIPS: JZ4740: Qi LB60: Remove support for AVT2 variant
  MIPS: pistachio: Determine SoC revision during boot
  MIPS: BMIPS: Adjust mips-hpt-frequency for BCM7435
  mips: mt7620: fallback to SDRAM when syscfg0 does not have a valid value for the memory type
  MIPS: Prevent "restoration" of MSA context in non-MSA kernels
  MIPS: cevt-r4k: Dynamically calculate min_delta_ns
  MIPS: malta-time: Take seconds into account
  MIPS: malta-time: Start GIC count before syncing to RTC
  MIPS: Force CPUs to lose FP context during mode switches
  ...
2016-05-19 10:02:26 -07:00
Peter Zijlstra 2e636d5e66 sched/preempt: Fix preempt_count manipulations
Vikram reported that his ARM64 compiler managed to 'optimize' away the
preempt_count manipulations in code like:

	preempt_enable_no_resched();
	put_user();
	preempt_disable();

Irrespective of that fact that that is horrible code that should be
fixed for many reasons, it does highlight a deficiency in the generic
preempt_count manipulators. As it is never right to combine/elide
preempt_count manipulations like this.

Therefore sprinkle some volatile in the two generic accessors to
ensure the compiler is aware of the fact that the preempt_count is
observed outside of the regular program-order view and thus cannot be
optimized away like this.

x86; the only arch not using the generic code is not affected as we
do all this in asm in order to use the segment base per-cpu stuff.

Reported-by: Vikram Mulukutla <markivx@codeaurora.org>
Tested-by: Vikram Mulukutla <markivx@codeaurora.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: a787870924 ("sched, arch: Create asm/preempt.h")
Link: http://lkml.kernel.org/r/20160516131751.GH3205@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-17 12:24:21 +02:00
Linus Torvalds 168f1a7163 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:
 "The main changes in this cycle were:

   - MSR access API fixes and enhancements (Andy Lutomirski)

   - early exception handling improvements (Andy Lutomirski)

   - user-space FS/GS prctl usage fixes and improvements (Andy
     Lutomirski)

   - Remove the cpu_has_*() APIs and replace them with equivalents
     (Borislav Petkov)

   - task switch micro-optimization (Brian Gerst)

   - 32-bit entry code simplification (Denys Vlasenko)

   - enhance PAT handling in enumated CPUs (Toshi Kani)

  ... and lots of other cleanups/fixlets"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits)
  x86/arch_prctl/64: Restore accidentally removed put_cpu() in ARCH_SET_GS
  x86/entry/32: Remove asmlinkage_protect()
  x86/entry/32: Remove GET_THREAD_INFO() from entry code
  x86/entry, sched/x86: Don't save/restore EFLAGS on task switch
  x86/asm/entry/32: Simplify pushes of zeroed pt_regs->REGs
  selftests/x86/ldt_gdt: Test set_thread_area() deletion of an active segment
  x86/tls: Synchronize segment registers in set_thread_area()
  x86/asm/64: Rename thread_struct's fs and gs to fsbase and gsbase
  x86/arch_prctl/64: Remove FSBASE/GSBASE < 4G optimization
  x86/segments/64: When load_gs_index fails, clear the base
  x86/segments/64: When loadsegment(fs, ...) fails, clear the base
  x86/asm: Make asm/alternative.h safe from assembly
  x86/asm: Stop depending on ptrace.h in alternative.h
  x86/entry: Rename is_{ia32,x32}_task() to in_{ia32,x32}_syscall()
  x86/asm: Make sure verify_cpu() has a good stack
  x86/extable: Add a comment about early exception handlers
  x86/msr: Set the return value to zero when native_rdmsr_safe() fails
  x86/paravirt: Make "unsafe" MSR accesses unsafe even if PARAVIRT=y
  x86/paravirt: Add paravirt_{read,write}_msr()
  x86/msr: Carry on after a non-"safe" MSR access fails
  ...
2016-05-16 15:15:17 -07:00
Linus Torvalds 3469d261ea Merge branch 'locking-rwsem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull support for killable rwsems from Ingo Molnar:
 "This, by Michal Hocko, implements down_write_killable().

  The main usecase will be to update mm_sem usage sites to use this new
  API, to allow the mm-reaper introduced in commit aac4536355 ("mm,
  oom: introduce oom reaper") to tear down oom victim address spaces
  asynchronously with minimum latencies and without deadlock worries"

[ The vfs will want it too as the inode lock is changed from a mutex to
  a rwsem due to the parallel lookup and readdir updates ]

* 'locking-rwsem-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/rwsem: Fix comment on register clobbering
  locking/rwsem: Fix down_write_killable()
  locking/rwsem, x86: Add frame annotation for call_rwsem_down_write_failed_killable()
  locking/rwsem: Provide down_write_killable()
  locking/rwsem, x86: Provide __down_write_killable()
  locking/rwsem, s390: Provide __down_write_killable()
  locking/rwsem, ia64: Provide __down_write_killable()
  locking/rwsem, alpha: Provide __down_write_killable()
  locking/rwsem: Introduce basis for down_write_killable()
  locking/rwsem, sparc: Drop superfluous arch specific implementation
  locking/rwsem, sh: Drop superfluous arch specific implementation
  locking/rwsem, xtensa: Drop superfluous arch specific implementation
  locking/rwsem: Drop explicit memory barriers
  locking/rwsem: Get rid of __down_write_nested()
2016-05-16 13:41:02 -07:00
James Hogan ca9eb49aa9 SIGNAL: Move generic copy_siginfo() to signal.h
The generic copy_siginfo() is currently defined in
asm-generic/siginfo.h, after including uapi/asm-generic/siginfo.h which
defines the generic struct siginfo. However this makes it awkward for an
architecture to use it if it has to define its own struct siginfo (e.g.
MIPS and potentially IA64), since it means that asm-generic/siginfo.h
can only be included after defining the arch-specific siginfo, which may
be problematic if the arch-specific definition needs definitions from
uapi/asm-generic/siginfo.h.

It is possible to work around this by first including
uapi/asm-generic/siginfo.h to get the constants before defining the
arch-specific siginfo, and include asm-generic/siginfo.h after. However
uapi headers can't be included by other uapi headers, so that first
include has to be in an ifdef __kernel__, with the non __kernel__ case
including the non-UAPI header instead.

Instead of that mess, move the generic copy_siginfo() definition into
linux/signal.h, which allows an arch-specific uapi/asm/siginfo.h to
include asm-generic/siginfo.h and define the arch-specific siginfo, and
for the generic copy_siginfo() to see that arch-specific definition.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Petr Malat <oss@malat.biz>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Christopher Ferris <cferris@google.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # 4.0-
Patchwork: https://patchwork.linux-mips.org/patch/12478/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:10 +02:00
Matt Redfearn c983f0e867 seccomp: Get compat syscalls from asm-generic header
Move retrieval of compat syscall numbers into inline function defined in
asm-generic header so that arches may override it.

[ralf@linux-mips.org: Resolve merge conflict.]

Suggested-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: IMG-MIPSLinuxKerneldevelopers@imgtec.com
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12978/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2016-05-13 14:02:00 +02:00
Joerg Roedel 8801561ce0 Merge branch 'for-joerg/arm-smmu/updates' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux into arm/smmu 2016-05-09 12:03:37 +02:00
Ingo Molnar 1fb48f8e54 Linux 4.6-rc6
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Merge tag 'v4.6-rc6' into x86/asm, to refresh the tree

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-05 08:35:00 +02:00
Robin Murphy e511267bc2 io-64-nonatomic: Add relaxed accessor variants
Whilst commit 9439eb3ab9 ("asm-generic: io: implement relaxed
accessor macros as conditional wrappers") makes the *_relaxed forms of
I/O accessors universally available to drivers, in cases where writeq()
is implemented via the io-64-nonatomic helpers, writeq_relaxed() will
end up falling back to writel() regardless of whether writel_relaxed()
is available (identically for s/write/read/).

Add corresponding relaxed forms of the nonatomic helpers to delegate
to the equivalent 32-bit accessors as appropriate. We also need to fix
io.h to avoid defining default relaxed variants if the basic accessors
themselves don't exist.

CC: Christoph Hellwig <hch@lst.de>
CC: Darren Hart <dvhart@linux.intel.com>
CC: Hitoshi Mitake <mitake.hitoshi@lab.ntt.co.jp>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-03 18:23:02 +01:00
Romain Perier fba7cd681b asm-generic/futex: Re-enable preemption in futex_atomic_cmpxchg_inatomic()
The recent decoupling of pagefault disable and preempt disable added an
explicit preempt_disable/enable() pair to the futex_atomic_cmpxchg_inatomic()
implementation in asm-generic/futex.h. But it forgot to add preempt_enable()
calls to the error handling code pathes, which results in a preemption count
imbalance.

This is observable on boot when the test for atomic_cmpxchg() is calling
futex_atomic_cmpxchg_inatomic() on a NULL pointer.

Add the missing preempt_enable() calls to the error handling code pathes.

[ tglx: Massaged changelog ]

Fixes: d9b9ff8c18 ("sched/preempt, futex: Disable preemption in UP futex_atomic_cmpxchg_inatomic() explicitly")
Signed-off-by: Romain Perier <romain.perier@free-electrons.com>
Cc: linux-arch@vger.kernel.org
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1460640963-690-1-git-send-email-romain.perier@free-electrons.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-04-21 11:06:09 +02:00
Borislav Petkov 91ed140d6c x86/asm: Make sure verify_cpu() has a good stack
04633df0c4 ("x86/cpu: Call verify_cpu() after having entered long mode too")
added the call to verify_cpu() for sanitizing CPU configuration.

The latter uses the stack minimally and it can happen that we land in
startup_64() directly from a 64-bit bootloader. Then we want to use our
own, known good stack.

Do that.

APs don't need this as the trampoline sets up a stack for them.

Reported-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mika Penttilä <mika.penttila@nextfour.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1459434062-31055-1-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13 11:52:19 +02:00
Michal Hocko d47996082f locking/rwsem: Introduce basis for down_write_killable()
Introduce a generic implementation necessary for down_write_killable().

This is a trivial extension of the already existing down_write() call
which can be interrupted by SIGKILL.  This patch doesn't provide
down_write_killable() yet because arches have to provide the necessary
pieces before.

rwsem_down_write_failed() which is a generic slow path for the
write lock is extended to take a task state and renamed to
__rwsem_down_write_failed_common(). The return value is either a valid
semaphore pointer or ERR_PTR(-EINTR).

rwsem_down_write_failed_killable() is exported as a new way to wait for
the lock and be killable.

For rwsem-spinlock implementation the current __down_write() it updated
in a similar way as __rwsem_down_write_failed_common() except it doesn't
need new exports just visible __down_write_killable().

Architectures which are not using the generic rwsem implementation are
supposed to provide their __down_write_killable() implementation and
use rwsem_down_write_failed_killable() for the slow path.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Signed-off-by: Jason Low <jason.low2@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: linux-xtensa@linux-xtensa.org
Cc: sparclinux@vger.kernel.org
Link: http://lkml.kernel.org/r/1460041951-22347-7-git-send-email-mhocko@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13 10:42:20 +02:00
Michal Hocko f8e04d8545 locking/rwsem: Get rid of __down_write_nested()
This is no longer used anywhere and all callers (__down_write()) use
0 as a subclass. Ditch __down_write_nested() to make the code easier
to follow.

This shouldn't introduce any functional change.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Signed-off-by: Jason Low <jason.low2@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-alpha@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-s390@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: linux-xtensa@linux-xtensa.org
Cc: sparclinux@vger.kernel.org
Link: http://lkml.kernel.org/r/1460041951-22347-2-git-send-email-mhocko@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-13 10:42:16 +02:00
Alexander Potapenko be7635e728 arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections
KASAN needs to know whether the allocation happens in an IRQ handler.
This lets us strip everything below the IRQ entry point to reduce the
number of unique stack traces needed to be stored.

Move the definition of __irq_entry to <linux/interrupt.h> so that the
users don't need to pull in <linux/ftrace.h>.  Also introduce the
__softirq_entry macro which is similar to __irq_entry, but puts the
corresponding functions to the .softirqentry.text section.

Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrey Konovalov <adech.fo@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Konstantin Serebryany <kcc@google.com>
Cc: Dmitry Chernenkov <dmitryc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-25 16:37:42 -07:00
Linus Torvalds 11caf57f6a asm-generic changes for 4.6
There are only three patches this time, most other changes to
 files in include/asm-generic tend to go through the tree of whoever
 depends on the change.
 
 Two patches are cleanups for stuff that is no longer needed,
 the main change is to adapt the generic version of BUG_ON()
 for CONFIG_BUG=n to make it behave consistently with BUG().
 
 This avoids undefined behavior along with a number of warnings
 about that undefined behavior in randconfig builds when
 we keep going on after hitting a BUG_ON().
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Merge tag 'asm-generic-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic updates from Arnd Bergmann:
 "There are only three patches this time, most other changes to files in
  include/asm-generic tend to go through the tree of whoever depends on
  the change.

  Two patches are cleanups for stuff that is no longer needed, the main
  change is to adapt the generic version of BUG_ON() for CONFIG_BUG=n to
  make it behave consistently with BUG().

  This avoids undefined behavior along with a number of warnings about
  that undefined behavior in randconfig builds when we keep going on
  after hitting a BUG_ON()"

* tag 'asm-generic-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  asm-generic: remove old nonatomic-io wrapper files
  asm-generic: default BUG_ON(x) to if(x)BUG()
  asm-generic: page.h: Remove useless get_user_page and free_user_page
2016-03-24 23:13:48 -07:00
Linus Torvalds 19d6f04cd3 Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
 "Documentation updates and a bitops ordering fix"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  bitops: Do not default to __clear_bit() for __clear_bit_unlock()
  documentation: Clarify compiler store-fusion example
  documentation: Transitivity is not cumulativity
  documentation:  Add alternative release-acquire outcome
  documentation: Distinguish between local and global transitivity
  documentation: Subsequent writes ordered by rcu_dereference()
  documentation: Remove obsolete reference to RCU-protected indexes
  documentation: Fix memory-barriers.txt section references
  documentation: Fix control dependency and identical stores
2016-03-24 09:36:18 -07:00
Peter Zijlstra f75d48644c bitops: Do not default to __clear_bit() for __clear_bit_unlock()
__clear_bit_unlock() is a special little snowflake. While it carries the
non-atomic '__' prefix, it is specifically documented to pair with
test_and_set_bit() and therefore should be 'somewhat' atomic.

Therefore the generic implementation of __clear_bit_unlock() cannot use
the fully non-atomic __clear_bit() as a default.

If an arch is able to do better; is must provide an implementation of
__clear_bit_unlock() itself.

Specifically, this came up as a result of hackbench livelock'ing in
slab_lock() on ARC with SMP + SLUB + !LLSC.

The issue was incorrect pairing of atomic ops.

 slab_lock() -> bit_spin_lock() -> test_and_set_bit()
 slab_unlock() -> __bit_spin_unlock() -> __clear_bit()

The non serializing __clear_bit() was getting "lost"

 80543b8e:	ld_s       r2,[r13,0] <--- (A) Finds PG_locked is set
 80543b90:	or         r3,r2,1    <--- (B) other core unlocks right here
 80543b94:	st_s       r3,[r13,0] <--- (C) sets PG_locked (overwrites unlock)

Fixes ARC STAR 9000817404 (and probably more).

Reported-by: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Tested-by: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Helge Deller <deller@gmx.de>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20160309114054.GJ6356@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-21 10:50:48 +01:00
Linus Torvalds 643ad15d47 Merge branch 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 protection key support from Ingo Molnar:
 "This tree adds support for a new memory protection hardware feature
  that is available in upcoming Intel CPUs: 'protection keys' (pkeys).

  There's a background article at LWN.net:

      https://lwn.net/Articles/643797/

  The gist is that protection keys allow the encoding of
  user-controllable permission masks in the pte.  So instead of having a
  fixed protection mask in the pte (which needs a system call to change
  and works on a per page basis), the user can map a (handful of)
  protection mask variants and can change the masks runtime relatively
  cheaply, without having to change every single page in the affected
  virtual memory range.

  This allows the dynamic switching of the protection bits of large
  amounts of virtual memory, via user-space instructions.  It also
  allows more precise control of MMU permission bits: for example the
  executable bit is separate from the read bit (see more about that
  below).

  This tree adds the MM infrastructure and low level x86 glue needed for
  that, plus it adds a high level API to make use of protection keys -
  if a user-space application calls:

        mmap(..., PROT_EXEC);

  or

        mprotect(ptr, sz, PROT_EXEC);

  (note PROT_EXEC-only, without PROT_READ/WRITE), the kernel will notice
  this special case, and will set a special protection key on this
  memory range.  It also sets the appropriate bits in the Protection
  Keys User Rights (PKRU) register so that the memory becomes unreadable
  and unwritable.

  So using protection keys the kernel is able to implement 'true'
  PROT_EXEC on x86 CPUs: without protection keys PROT_EXEC implies
  PROT_READ as well.  Unreadable executable mappings have security
  advantages: they cannot be read via information leaks to figure out
  ASLR details, nor can they be scanned for ROP gadgets - and they
  cannot be used by exploits for data purposes either.

  We know about no user-space code that relies on pure PROT_EXEC
  mappings today, but binary loaders could start making use of this new
  feature to map binaries and libraries in a more secure fashion.

  There is other pending pkeys work that offers more high level system
  call APIs to manage protection keys - but those are not part of this
  pull request.

  Right now there's a Kconfig that controls this feature
  (CONFIG_X86_INTEL_MEMORY_PROTECTION_KEYS) that is default enabled
  (like most x86 CPU feature enablement code that has no runtime
  overhead), but it's not user-configurable at the moment.  If there's
  any serious problem with this then we can make it configurable and/or
  flip the default"

* 'mm-pkeys-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
  x86/mm/pkeys: Fix mismerge of protection keys CPUID bits
  mm/pkeys: Fix siginfo ABI breakage caused by new u64 field
  x86/mm/pkeys: Fix access_error() denial of writes to write-only VMA
  mm/core, x86/mm/pkeys: Add execute-only protection keys support
  x86/mm/pkeys: Create an x86 arch_calc_vm_prot_bits() for VMA flags
  x86/mm/pkeys: Allow kernel to modify user pkey rights register
  x86/fpu: Allow setting of XSAVE state
  x86/mm: Factor out LDT init from context init
  mm/core, x86/mm/pkeys: Add arch_validate_pkey()
  mm/core, arch, powerpc: Pass a protection key in to calc_vm_flag_bits()
  x86/mm/pkeys: Actually enable Memory Protection Keys in the CPU
  x86/mm/pkeys: Add Kconfig prompt to existing config option
  x86/mm/pkeys: Dump pkey from VMA in /proc/pid/smaps
  x86/mm/pkeys: Dump PKRU with other kernel registers
  mm/core, x86/mm/pkeys: Differentiate instruction fetches
  x86/mm/pkeys: Optimize fault handling in access_error()
  mm/core: Do not enforce PKEY permissions on remote mm access
  um, pkeys: Add UML arch_*_access_permitted() methods
  mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys
  x86/mm/gup: Simplify get_user_pages() PTE bit handling
  ...
2016-03-20 19:08:56 -07:00
Linus Torvalds 1200b6809d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights:

   1) Support more Realtek wireless chips, from Jes Sorenson.

   2) New BPF types for per-cpu hash and arrap maps, from Alexei
      Starovoitov.

   3) Make several TCP sysctls per-namespace, from Nikolay Borisov.

   4) Allow the use of SO_REUSEPORT in order to do per-thread processing
   of incoming TCP/UDP connections.  The muxing can be done using a
   BPF program which hashes the incoming packet.  From Craig Gallek.

   5) Add a multiplexer for TCP streams, to provide a messaged based
      interface.  BPF programs can be used to determine the message
      boundaries.  From Tom Herbert.

   6) Add 802.1AE MACSEC support, from Sabrina Dubroca.

   7) Avoid factorial complexity when taking down an inetdev interface
      with lots of configured addresses.  We were doing things like
      traversing the entire address less for each address removed, and
      flushing the entire netfilter conntrack table for every address as
      well.

   8) Add and use SKB bulk free infrastructure, from Jesper Brouer.

   9) Allow offloading u32 classifiers to hardware, and implement for
      ixgbe, from John Fastabend.

  10) Allow configuring IRQ coalescing parameters on a per-queue basis,
      from Kan Liang.

  11) Extend ethtool so that larger link mode masks can be supported.
      From David Decotigny.

  12) Introduce devlink, which can be used to configure port link types
      (ethernet vs Infiniband, etc.), port splitting, and switch device
      level attributes as a whole.  From Jiri Pirko.

  13) Hardware offload support for flower classifiers, from Amir Vadai.

  14) Add "Local Checksum Offload".  Basically, for a tunneled packet
      the checksum of the outer header is 'constant' (because with the
      checksum field filled into the inner protocol header, the payload
      of the outer frame checksums to 'zero'), and we can take advantage
      of that in various ways.  From Edward Cree"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1548 commits)
  bonding: fix bond_get_stats()
  net: bcmgenet: fix dma api length mismatch
  net/mlx4_core: Fix backward compatibility on VFs
  phy: mdio-thunder: Fix some Kconfig typos
  lan78xx: add ndo_get_stats64
  lan78xx: handle statistics counter rollover
  RDS: TCP: Remove unused constant
  RDS: TCP: Add sysctl tunables for sndbuf/rcvbuf on rds-tcp socket
  net: smc911x: convert pxa dma to dmaengine
  team: remove duplicate set of flag IFF_MULTICAST
  bonding: remove duplicate set of flag IFF_MULTICAST
  net: fix a comment typo
  ethernet: micrel: fix some error codes
  ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it
  bpf, dst: add and use dst_tclassid helper
  bpf: make skb->tc_classid also readable
  net: mvneta: bm: clarify dependencies
  cls_bpf: reset class and reuse major in da
  ldmvsw: Checkpatch sunvnet.c and sunvnet_common.c
  ldmvsw: Add ldmvsw.c driver code
  ...
2016-03-19 10:05:34 -07:00
Linus Torvalds 814a2bf957 Merge branch 'akpm' (patches from Andrew)
Merge second patch-bomb from Andrew Morton:

 - a couple of hotfixes

 - the rest of MM

 - a new timer slack control in procfs

 - a couple of procfs fixes

 - a few misc things

 - some printk tweaks

 - lib/ updates, notably to radix-tree.

 - add my and Nick Piggin's old userspace radix-tree test harness to
   tools/testing/radix-tree/.  Matthew said it was a godsend during the
   radix-tree work he did.

 - a few code-size improvements, switching to __always_inline where gcc
   screwed up.

 - partially implement character sets in sscanf

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
  sscanf: implement basic character sets
  lib/bug.c: use common WARN helper
  param: convert some "on"/"off" users to strtobool
  lib: add "on"/"off" support to kstrtobool
  lib: update single-char callers of strtobool()
  lib: move strtobool() to kstrtobool()
  include/linux/unaligned: force inlining of byteswap operations
  include/uapi/linux/byteorder, swab: force inlining of some byteswap operations
  include/asm-generic/atomic-long.h: force inlining of some atomic_long operations
  usb: common: convert to use match_string() helper
  ide: hpt366: convert to use match_string() helper
  ata: hpt366: convert to use match_string() helper
  power: ab8500: convert to use match_string() helper
  power: charger_manager: convert to use match_string() helper
  drm/edid: convert to use match_string() helper
  pinctrl: convert to use match_string() helper
  device property: convert to use match_string() helper
  lib/string: introduce match_string() helper
  radix-tree tests: add test for radix_tree_iter_next
  radix-tree tests: add regression3 test
  ...
2016-03-18 19:26:54 -07:00
Linus Torvalds 1a46712aa9 This is the bulk of GPIO changes for kernel v4.6:
Core changes:
 
 - The gpio_chip is now a *real device*. Until now the gpio chips
   were just piggybacking the parent device or (gasp) floating in
   space outside of the device model. We now finally make GPIO chips
   devices. The gpio_chip will create a gpio_device which contains
   a struct device, and this gpio_device struct is kept private.
   Anything that needs to be kept private from the rest of the kernel
   will gradually be moved over to the gpio_device.
 
 - As a result of making the gpio_device a real device, we have added
   resource management, so devm_gpiochip_add_data() will cut down on
   overhead and reduce code lines. A huge slew of patches convert
   almost all drivers in the subsystem to use this.
 
 - Building on making the GPIO a real device, we add the first step
   of a new userspace ABI: the GPIO character device. We take small
   steps here, so we first add a pure *information* ABI and the tool
   "lsgpio" that will list all GPIO devices on the system and all
   lines on these devices. We can now discover GPIOs properly from
   userspace. We still have not come up with a way to actually *use*
   GPIOs from userspace.
 
 - To encourage people to use the character device for the future,
   we have it always-enabled when using GPIO. The old sysfs ABI is
   still opt-in (and can be used in parallel), but is marked as
   deprecated. We will keep it around for the foreseeable future,
   but it will not be extended to cover ever more use cases.
 
 Cleanup:
 
 - Bjorn Helgaas removed a whole slew of per-architecture <asm/gpio.h>
   includes. This dates back to when GPIO was an opt-in feature and
   no shared library even existed: just a header file with proper
   prototypes was provided and all semantics were up to the arch to
   implement. These patches make the GPIO chip even more a proper
   device and cleans out leftovers of the old in-kernel API here
   and there. Still some cruft is left but it's very little now.
 
 - There is still some clamping of return values for .get() going
   on, but we now return sane values in the vast majority of drivers
   and the errorpath is sanitized. Some patches for powerpc, blackfin
   and unicore still drop in.
 
 - We continue to switch the ARM, MIPS, blackfin, m68k local GPIO
   implementations to use gpiochip_add_data() and cut down on code
   lines.
 
 - MPC8xxx is converted to use the generic GPIO helpers.
 
 - ATH79 is converted to use the generic GPIO helpers.
 
 New drivers:
 
 - WinSystems WS16C48
 
 - Acces 104-DIO-48E
 
 - F81866 (a F7188x variant)
 
 - Qoric (a MPC8xxx variant)
 
 - TS-4800
 
 - SPI serializers (pisosr): simple 74xx shift registers connected
   to SPI to obtain a dirt-cheap output-only GPIO expander.
 
 - Texas Instruments TPIC2810
 
 - Texas Instruments TPS65218
 
 - Texas Instruments TPS65912
 
 - X-Gene (ARM64) standby GPIO controller
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Merge tag 'gpio-v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for kernel v4.6.  There is quite a
  lot of interesting stuff going on.

  The patches to other subsystems and arch-wide are ACKed as far as
  possible, though I consider things like per-arch <asm/gpio.h> as
  essentially a part of the GPIO subsystem so it should not be needed.

  Core changes:

   - The gpio_chip is now a *real device*.  Until now the gpio chips
     were just piggybacking the parent device or (gasp) floating in
     space outside of the device model.

     We now finally make GPIO chips devices.  The gpio_chip will create
     a gpio_device which contains a struct device, and this gpio_device
     struct is kept private.  Anything that needs to be kept private
     from the rest of the kernel will gradually be moved over to the
     gpio_device.

   - As a result of making the gpio_device a real device, we have added
     resource management, so devm_gpiochip_add_data() will cut down on
     overhead and reduce code lines.  A huge slew of patches convert
     almost all drivers in the subsystem to use this.

   - Building on making the GPIO a real device, we add the first step of
     a new userspace ABI: the GPIO character device.  We take small
     steps here, so we first add a pure *information* ABI and the tool
     "lsgpio" that will list all GPIO devices on the system and all
     lines on these devices.

     We can now discover GPIOs properly from userspace.  We still have
     not come up with a way to actually *use* GPIOs from userspace.

   - To encourage people to use the character device for the future, we
     have it always-enabled when using GPIO.  The old sysfs ABI is still
     opt-in (and can be used in parallel), but is marked as deprecated.

     We will keep it around for the foreseeable future, but it will not
     be extended to cover ever more use cases.

  Cleanup:

   - Bjorn Helgaas removed a whole slew of per-architecture <asm/gpio.h>
     includes.

     This dates back to when GPIO was an opt-in feature and no shared
     library even existed: just a header file with proper prototypes was
     provided and all semantics were up to the arch to implement.  These
     patches make the GPIO chip even more a proper device and cleans out
     leftovers of the old in-kernel API here and there.

     Still some cruft is left but it's very little now.

   - There is still some clamping of return values for .get() going on,
     but we now return sane values in the vast majority of drivers and
     the errorpath is sanitized.  Some patches for powerpc, blackfin and
     unicore still drop in.

   - We continue to switch the ARM, MIPS, blackfin, m68k local GPIO
     implementations to use gpiochip_add_data() and cut down on code
     lines.

   - MPC8xxx is converted to use the generic GPIO helpers.

   - ATH79 is converted to use the generic GPIO helpers.

  New drivers:

   - WinSystems WS16C48

   - Acces 104-DIO-48E

   - F81866 (a F7188x variant)

   - Qoric (a MPC8xxx variant)

   - TS-4800

   - SPI serializers (pisosr): simple 74xx shift registers connected to
     SPI to obtain a dirt-cheap output-only GPIO expander.

   - Texas Instruments TPIC2810

   - Texas Instruments TPS65218

   - Texas Instruments TPS65912

   - X-Gene (ARM64) standby GPIO controller"

* tag 'gpio-v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (194 commits)
  Revert "Share upstreaming patches"
  gpio: mcp23s08: Fix clearing of interrupt.
  gpiolib: Fix comment referring to gpio_*() in gpiod_*()
  gpio: pca953x: Fix pca953x_gpio_set_multiple() on 64-bit
  gpio: xgene: Fix kconfig for standby GIPO contoller
  gpio: Add generic serializer DT binding
  gpio: uapi: use 0xB4 as ioctl() major
  gpio: tps65912: fix bad merge
  Revert "gpio: lp3943: Drop pin_used and lp3943_gpio_request/lp3943_gpio_free"
  gpio: omap: drop dev field from gpio_bank structure
  gpio: mpc8xxx: Slightly update the code for better readability
  gpio: mpc8xxx: Remove *read_reg and *write_reg from struct mpc8xxx_gpio_chip
  gpio: mpc8xxx: Fixup setting gpio direction output
  gpio: mcp23s08: Add support for mcp23s18
  dt-bindings: gpio: altera: Fix altr,interrupt-type property
  gpio: add driver for MEN 16Z127 GPIO controller
  gpio: lp3943: Drop pin_used and lp3943_gpio_request/lp3943_gpio_free
  gpio: timberdale: Switch to devm_ioremap_resource()
  gpio: ts4800: Add IMX51 dependency
  gpiolib: rewrite gpiodev_add_to_list
  ...
2016-03-17 21:05:32 -07:00
Linus Torvalds 588ab3f9af arm64 updates for 4.6:
- Initial page table creation reworked to avoid breaking large block
   mappings (huge pages) into smaller ones. The ARM architecture requires
   break-before-make in such cases to avoid TLB conflicts but that's not
   always possible on live page tables
 
 - Kernel virtual memory layout: the kernel image is no longer linked to
   the bottom of the linear mapping (PAGE_OFFSET) but at the bottom of
   the vmalloc space, allowing the kernel to be loaded (nearly) anywhere
   in physical RAM
 
 - Kernel ASLR: position independent kernel Image and modules being
   randomly mapped in the vmalloc space with the randomness is provided
   by UEFI (efi_get_random_bytes() patches merged via the arm64 tree,
   acked by Matt Fleming)
 
 - Implement relative exception tables for arm64, required by KASLR
   (initial code for ARCH_HAS_RELATIVE_EXTABLE added to lib/extable.c but
   actual x86 conversion to deferred to 4.7 because of the merge
   dependencies)
 
 - Support for the User Access Override feature of ARMv8.2: this allows
   uaccess functions (get_user etc.) to be implemented using LDTR/STTR
   instructions. Such instructions, when run by the kernel, perform
   unprivileged accesses adding an extra level of protection. The
   set_fs() macro is used to "upgrade" such instruction to privileged
   accesses via the UAO bit
 
 - Half-precision floating point support (part of ARMv8.2)
 
 - Optimisations for CPUs with or without a hardware prefetcher (using
   run-time code patching)
 
 - copy_page performance improvement to deal with 128 bytes at a time
 
 - Sanity checks on the CPU capabilities (via CPUID) to prevent
   incompatible secondary CPUs from being brought up (e.g. weird
   big.LITTLE configurations)
 
 - valid_user_regs() reworked for better sanity check of the sigcontext
   information (restored pstate information)
 
 - ACPI parking protocol implementation
 
 - CONFIG_DEBUG_RODATA enabled by default
 
 - VDSO code marked as read-only
 
 - DEBUG_PAGEALLOC support
 
 - ARCH_HAS_UBSAN_SANITIZE_ALL enabled
 
 - Erratum workaround Cavium ThunderX SoC
 
 - set_pte_at() fix for PROT_NONE mappings
 
 - Code clean-ups
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:
 "Here are the main arm64 updates for 4.6.  There are some relatively
  intrusive changes to support KASLR, the reworking of the kernel
  virtual memory layout and initial page table creation.

  Summary:

   - Initial page table creation reworked to avoid breaking large block
     mappings (huge pages) into smaller ones.  The ARM architecture
     requires break-before-make in such cases to avoid TLB conflicts but
     that's not always possible on live page tables

   - Kernel virtual memory layout: the kernel image is no longer linked
     to the bottom of the linear mapping (PAGE_OFFSET) but at the bottom
     of the vmalloc space, allowing the kernel to be loaded (nearly)
     anywhere in physical RAM

   - Kernel ASLR: position independent kernel Image and modules being
     randomly mapped in the vmalloc space with the randomness is
     provided by UEFI (efi_get_random_bytes() patches merged via the
     arm64 tree, acked by Matt Fleming)

   - Implement relative exception tables for arm64, required by KASLR
     (initial code for ARCH_HAS_RELATIVE_EXTABLE added to lib/extable.c
     but actual x86 conversion to deferred to 4.7 because of the merge
     dependencies)

   - Support for the User Access Override feature of ARMv8.2: this
     allows uaccess functions (get_user etc.) to be implemented using
     LDTR/STTR instructions.  Such instructions, when run by the kernel,
     perform unprivileged accesses adding an extra level of protection.
     The set_fs() macro is used to "upgrade" such instruction to
     privileged accesses via the UAO bit

   - Half-precision floating point support (part of ARMv8.2)

   - Optimisations for CPUs with or without a hardware prefetcher (using
     run-time code patching)

   - copy_page performance improvement to deal with 128 bytes at a time

   - Sanity checks on the CPU capabilities (via CPUID) to prevent
     incompatible secondary CPUs from being brought up (e.g.  weird
     big.LITTLE configurations)

   - valid_user_regs() reworked for better sanity check of the
     sigcontext information (restored pstate information)

   - ACPI parking protocol implementation

   - CONFIG_DEBUG_RODATA enabled by default

   - VDSO code marked as read-only

   - DEBUG_PAGEALLOC support

   - ARCH_HAS_UBSAN_SANITIZE_ALL enabled

   - Erratum workaround Cavium ThunderX SoC

   - set_pte_at() fix for PROT_NONE mappings

   - Code clean-ups"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (99 commits)
  arm64: kasan: Fix zero shadow mapping overriding kernel image shadow
  arm64: kasan: Use actual memory node when populating the kernel image shadow
  arm64: Update PTE_RDONLY in set_pte_at() for PROT_NONE permission
  arm64: Fix misspellings in comments.
  arm64: efi: add missing frame pointer assignment
  arm64: make mrs_s prefixing implicit in read_cpuid
  arm64: enable CONFIG_DEBUG_RODATA by default
  arm64: Rework valid_user_regs
  arm64: mm: check at build time that PAGE_OFFSET divides the VA space evenly
  arm64: KVM: Move kvm_call_hyp back to its original localtion
  arm64: mm: treat memstart_addr as a signed quantity
  arm64: mm: list kernel sections in order
  arm64: lse: deal with clobbered IP registers after branch via PLT
  arm64: mm: dump: Use VA_START directly instead of private LOWEST_ADDR
  arm64: kconfig: add submenu for 8.2 architectural features
  arm64: kernel: acpi: fix ioremap in ACPI parking protocol cpu_postboot
  arm64: Add support for Half precision floating point
  arm64: Remove fixmap include fragility
  arm64: Add workaround for Cavium erratum 27456
  arm64: mm: Mark .rodata as RO
  ...
2016-03-17 20:03:47 -07:00
Josh Poimboeuf 2553b67a1f lib/bug.c: use common WARN helper
The traceoff_on_warning option doesn't have any effect on s390, powerpc,
arm64, parisc, and sh because there are two different types of WARN
implementations:

1) The above mentioned architectures treat WARN() as a special case of a
   BUG() exception.  They handle warnings in report_bug() in lib/bug.c.

2) All other architectures just call warn_slowpath_*() directly.  Their
   warnings are handled in warn_slowpath_common() in kernel/panic.c.

Support traceoff_on_warning on all architectures and prevent any future
divergence by using a single common function to emit the warning.

Also remove the '()' from '%pS()', because the parentheses look funky:

  [   45.607629] WARNING: at /root/warn_mod/warn_mod.c:17 .init_dummy+0x20/0x40 [warn_mod]()

Reported-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Denys Vlasenko a644fdf029 include/asm-generic/atomic-long.h: force inlining of some atomic_long operations
Sometimes gcc mysteriously doesn't inline
very small functions we expect to be inlined. See

    https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122

With this .config:
http://busybox.net/~vda/kernel_config_OPTIMIZE_INLINING_and_Os,
atomic_long_inc(), atomic_long_dec() and atomic_long_add()
functions get deinlined about 40 times. Examples of disassembly:

<atomic_long_inc> (21 copies, 147 calls):
       55                      push   %rbp
       48 89 e5                mov    %rsp,%rbp
       f0 48 ff 07             lock incq (%rdi)
       5d                      pop    %rbp
       c3                      retq

<atomic_long_dec> (4 copies, 14 calls) is similar to inc.

<atomic_long_add> (11 copies, 41 calls):
       55                      push   %rbp
       48 89 e5                mov    %rsp,%rbp
       f0 48 01 3e             lock add %rdi,(%rsi)
       5d                      pop    %rbp
       c3                      retq

This patch fixes this via s/inline/__always_inline/.
Code size decrease after the patch is ~1.3k:

    text     data      bss       dec     hex filename
92203657 20826112 36417536 149447305 8e86289 vmlinux
92202377 20826112 36417536 149446025 8e85d89 vmlinux4_atomiclong_after

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Steven Rostedt dfbf2897d0 bug: set warn variable before calling WARN()
This has hit me a couple of times already.  I would be debugging code
and the system would simply hang and then reboot.  Finally, I found that
the problem was caused by WARN_ON_ONCE() and friends.

The macro WARN_ON_ONCE(condition) is defined as:

	static bool __section(.data.unlikely) __warned;
	int __ret_warn_once = !!(condition);

	if (unlikely(__ret_warn_once))
		if (WARN_ON(!__warned))
			__warned = true;

	unlikely(__ret_warn_once);

Which looks great and all.  But what I have hit, is an issue when
WARN_ON() itself hits the same WARN_ON_ONCE() code.  Because, the
variable __warned is not yet set.  Then it too calls WARN_ON() and that
triggers the warning again.  It keeps doing this until the stack is
overflowed and the system crashes.

By setting __warned first before calling WARN_ON() makes the original
WARN_ON_ONCE() really only warn once, and not an infinite amount of
times if the WARN_ON() also triggers the warning.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Aneesh Kumar K.V 458aa76d13 mm/thp/migration: switch from flush_tlb_range to flush_pmd_tlb_range
We remove one instace of flush_tlb_range here.  That was added by commit
f714f4f20e ("mm: numa: call MMU notifiers on THP migration").  But the
pmdp_huge_clear_flush_notify should have done the require flush for us.
Hence remove the extra flush.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-17 15:09:34 -07:00
Linus Torvalds 96b9b1c956 TTY/Serial patches for 4.6-rc1
Here's the big tty/serial driver pull request for 4.6-rc1.
 
 Lots of changes in here, Peter has been on a tear again, with lots of
 refactoring and bugs fixes, many thanks to the great work he has been
 doing.  Lots of driver updates and fixes as well, full details in the
 shortlog.
 
 All have been in linux-next for a while with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here's the big tty/serial driver pull request for 4.6-rc1.

  Lots of changes in here, Peter has been on a tear again, with lots of
  refactoring and bugs fixes, many thanks to the great work he has been
  doing.  Lots of driver updates and fixes as well, full details in the
  shortlog.

  All have been in linux-next for a while with no reported issues"

* tag 'tty-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (220 commits)
  serial: 8250: describe CONFIG_SERIAL_8250_RSA
  serial: samsung: optimize UART rx fifo access routine
  serial: pl011: add mark/space parity support
  serial: sa1100: make sa1100_register_uart_fns a function
  tty: serial: 8250: add MOXA Smartio MUE boards support
  serial: 8250: convert drivers to use up_to_u8250p()
  serial: 8250/mediatek: fix building with SERIAL_8250=m
  serial: 8250/ingenic: fix building with SERIAL_8250=m
  serial: 8250/uniphier: fix modular build
  Revert "drivers/tty/serial: make 8250/8250_ingenic.c explicitly non-modular"
  Revert "drivers/tty/serial: make 8250/8250_mtk.c explicitly non-modular"
  serial: mvebu-uart: initial support for Armada-3700 serial port
  serial: mctrl_gpio: Add missing module license
  serial: ifx6x60: avoid uninitialized variable use
  tty/serial: at91: fix bad offset for UART timeout register
  tty/serial: at91: restore dynamic driver binding
  serial: 8250: Add hardware dependency to RT288X option
  TTY, devpts: document pty count limiting
  tty: goldfish: support platform_device with id -1
  drivers: tty: goldfish: Add device tree bindings
  ...
2016-03-17 13:53:25 -07:00
Linus Torvalds 63e30271b0 PCI changes for the v4.6 merge window:
Enumeration
     Disable IO/MEM decoding for devices with non-compliant BARs (Bjorn Helgaas)
     Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs (Bjorn Helgaas
 
   Resource management
     Mark shadow copy of VGA ROM as IORESOURCE_PCI_FIXED (Bjorn Helgaas)
     Don't assign or reassign immutable resources (Bjorn Helgaas)
     Don't enable/disable ROM BAR if we're using a RAM shadow copy (Bjorn Helgaas)
     Set ROM shadow location in arch code, not in PCI core (Bjorn Helgaas)
     Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs (Bjorn Helgaas)
     ia64: Use ioremap() instead of open-coded equivalent (Bjorn Helgaas)
     ia64: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
     MIPS: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
     Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY (Bjorn Helgaas)
     Don't leak memory if sysfs_create_bin_file() fails (Bjorn Helgaas)
     rcar: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
     designware: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
 
   Virtualization
     Wait for up to 1000ms after FLR reset (Alex Williamson)
     Support SR-IOV on any function type (Kelly Zytaruk)
     Add ACS quirk for all Cavium devices (Manish Jaggi)
 
   AER
     Rename pci_ops_aer to aer_inj_pci_ops (Bjorn Helgaas)
     Restore pci_ops pointer while calling original pci_ops (David Daney)
     Fix aer_inject error codes (Jean Delvare)
     Use dev_warn() in aer_inject (Jean Delvare)
     Log actual error causes in aer_inject (Jean Delvare)
     Log aer_inject error injections (Jean Delvare)
 
   VPD
     Prevent VPD access for buggy devices (Babu Moger)
     Move pci_read_vpd() and pci_write_vpd() close to other VPD code (Bjorn Helgaas)
     Move pci_vpd_release() from header file to pci/access.c (Bjorn Helgaas)
     Remove struct pci_vpd_ops.release function pointer (Bjorn Helgaas)
     Rename VPD symbols to remove unnecessary "pci22" (Bjorn Helgaas)
     Fold struct pci_vpd_pci22 into struct pci_vpd (Bjorn Helgaas)
     Sleep rather than busy-wait for VPD access completion (Bjorn Helgaas)
     Update VPD definitions (Hannes Reinecke)
     Allow access to VPD attributes with size 0 (Hannes Reinecke)
     Determine actual VPD size on first access (Hannes Reinecke)
 
   Generic host bridge driver
     Move structure definitions to separate header file (David Daney)
     Add pci_host_common_probe(), based on gen_pci_probe() (David Daney)
     Expose pci_host_common_probe() for use by other drivers (David Daney)
 
   Altera host bridge driver
     Fix altera_pcie_link_is_up() (Ley Foon Tan)
 
   Cavium ThunderX host bridge driver
     Add PCIe host driver for ThunderX processors (David Daney)
     Add driver for ThunderX-pass{1,2} on-chip devices (David Daney)
 
   Freescale i.MX6 host bridge driver
     Add DT bindings to configure PHY Tx driver settings (Justin Waters)
     Move imx6_pcie_reset_phy() near other PHY handling functions (Lucas Stach)
     Move PHY reset into imx6_pcie_establish_link() (Lucas Stach)
     Remove broken Gen2 workaround (Lucas Stach)
     Move link up check into imx6_pcie_wait_for_link() (Lucas Stach)
 
   Freescale Layerscape host bridge driver
     Add "fsl,ls2085a-pcie" compatible ID (Yang Shi)
 
   Intel VMD host bridge driver
     Attach VMD resources to parent domain's resource tree (Jon Derrick)
     Set bus resource start to 0 (Keith Busch)
 
   Microsoft Hyper-V host bridge driver
     Add fwnode_handle to x86 pci_sysdata (Jake Oshins)
     Look up IRQ domain by fwnode_handle (Jake Oshins)
     Add paravirtual PCI front-end for Microsoft Hyper-V VMs (Jake Oshins)
 
   NVIDIA Tegra host bridge driver
     Add pci_ops.{add,remove}_bus() callbacks (Thierry Reding)
     Implement ->{add,remove}_bus() callbacks (Thierry Reding)
     Remove unused struct tegra_pcie.num_ports field (Thierry Reding)
     Track bus -> CPU mapping (Thierry Reding)
     Remove misleading PHYS_OFFSET (Thierry Reding)
 
   Renesas R-Car host bridge driver
     Depend on ARCH_RENESAS, not ARCH_SHMOBILE (Simon Horman)
 
   Synopsys DesignWare host bridge driver
     ARC: Add PCI support (Joao Pinto)
     Add generic dw_pcie_wait_for_link() (Joao Pinto)
     Add default link up check if sub-driver doesn't override (Joao Pinto)
     Add driver for prototyping kits based on ARC SDP (Joao Pinto)
 
   TI Keystone host bridge driver
     Defer probing if devm_phy_get() returns -EPROBE_DEFER (Shawn Lin)
 
   Xilinx AXI host bridge driver
     Use of_pci_get_host_bridge_resources() to parse DT (Bharat Kumar Gogada)
     Remove dependency on ARM-specific struct hw_pci (Bharat Kumar Gogada)
     Don't call pci_fixup_irqs() on Microblaze (Bharat Kumar Gogada)
     Update Zynq binding with Microblaze node (Bharat Kumar Gogada)
     microblaze: Support generic Xilinx AXI PCIe Host Bridge IP driver (Bharat Kumar Gogada)
 
   Xilinx NWL host bridge driver
     Add support for Xilinx NWL PCIe Host Controller (Bharat Kumar Gogada)
 
   Miscellaneous
     Check device_attach() return value always (Bjorn Helgaas)
     Move pci_set_flags() from asm-generic/pci-bridge.h to linux/pci.h (Bjorn Helgaas)
     Remove includes of empty asm-generic/pci-bridge.h (Bjorn Helgaas)
     ARM64: Remove generated include of asm-generic/pci-bridge.h (Bjorn Helgaas)
     Remove empty asm-generic/pci-bridge.h (Bjorn Helgaas)
     Remove includes of asm/pci-bridge.h (Bjorn Helgaas)
     Consolidate PCI DMA constants and interfaces in linux/pci-dma-compat.h (Bjorn Helgaas)
     unicore32: Remove unused HAVE_ARCH_PCI_SET_DMA_MASK definition (Bjorn Helgaas)
     Cleanup pci/pcie/Kconfig whitespace (Andreas Ziegler)
     Include pci/hotplug Kconfig directly from pci/Kconfig (Bjorn Helgaas)
     Include pci/pcie/Kconfig directly from pci/Kconfig (Bogicevic Sasa)
     frv: Remove stray pci_{alloc,free}_consistent() declaration (Christoph Hellwig)
     Move pci_dma_* helpers to common code (Christoph Hellwig)
     Add PCI_CLASS_SERIAL_USB_DEVICE definition (Heikki Krogerus)
     Add QEMU top-level IDs for (sub)vendor & device (Robin H. Johnson)
     Fix broken URL for Dell biosdevname (Naga Venkata Sai Indubhaskar Jupudi)
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Merge tag 'pci-v4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:
 "PCI changes for v4.6:

  Enumeration:
   - Disable IO/MEM decoding for devices with non-compliant BARs (Bjorn Helgaas)
   - Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs (Bjorn Helgaas

  Resource management:
   - Mark shadow copy of VGA ROM as IORESOURCE_PCI_FIXED (Bjorn Helgaas)
   - Don't assign or reassign immutable resources (Bjorn Helgaas)
   - Don't enable/disable ROM BAR if we're using a RAM shadow copy (Bjorn Helgaas)
   - Set ROM shadow location in arch code, not in PCI core (Bjorn Helgaas)
   - Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs (Bjorn Helgaas)
   - ia64: Use ioremap() instead of open-coded equivalent (Bjorn Helgaas)
   - ia64: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
   - MIPS: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
   - Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY (Bjorn Helgaas)
   - Don't leak memory if sysfs_create_bin_file() fails (Bjorn Helgaas)
   - rcar: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
   - designware: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)

  Virtualization:
   - Wait for up to 1000ms after FLR reset (Alex Williamson)
   - Support SR-IOV on any function type (Kelly Zytaruk)
   - Add ACS quirk for all Cavium devices (Manish Jaggi)

  AER:
   - Rename pci_ops_aer to aer_inj_pci_ops (Bjorn Helgaas)
   - Restore pci_ops pointer while calling original pci_ops (David Daney)
   - Fix aer_inject error codes (Jean Delvare)
   - Use dev_warn() in aer_inject (Jean Delvare)
   - Log actual error causes in aer_inject (Jean Delvare)
   - Log aer_inject error injections (Jean Delvare)

  VPD:
   - Prevent VPD access for buggy devices (Babu Moger)
   - Move pci_read_vpd() and pci_write_vpd() close to other VPD code (Bjorn Helgaas)
   - Move pci_vpd_release() from header file to pci/access.c (Bjorn Helgaas)
   - Remove struct pci_vpd_ops.release function pointer (Bjorn Helgaas)
   - Rename VPD symbols to remove unnecessary "pci22" (Bjorn Helgaas)
   - Fold struct pci_vpd_pci22 into struct pci_vpd (Bjorn Helgaas)
   - Sleep rather than busy-wait for VPD access completion (Bjorn Helgaas)
   - Update VPD definitions (Hannes Reinecke)
   - Allow access to VPD attributes with size 0 (Hannes Reinecke)
   - Determine actual VPD size on first access (Hannes Reinecke)

  Generic host bridge driver:
   - Move structure definitions to separate header file (David Daney)
   - Add pci_host_common_probe(), based on gen_pci_probe() (David Daney)
   - Expose pci_host_common_probe() for use by other drivers (David Daney)

  Altera host bridge driver:
   - Fix altera_pcie_link_is_up() (Ley Foon Tan)

  Cavium ThunderX host bridge driver:
   - Add PCIe host driver for ThunderX processors (David Daney)
   - Add driver for ThunderX-pass{1,2} on-chip devices (David Daney)

  Freescale i.MX6 host bridge driver:
   - Add DT bindings to configure PHY Tx driver settings (Justin Waters)
   - Move imx6_pcie_reset_phy() near other PHY handling functions (Lucas Stach)
   - Move PHY reset into imx6_pcie_establish_link() (Lucas Stach)
   - Remove broken Gen2 workaround (Lucas Stach)
   - Move link up check into imx6_pcie_wait_for_link() (Lucas Stach)

  Freescale Layerscape host bridge driver:
   - Add "fsl,ls2085a-pcie" compatible ID (Yang Shi)

  Intel VMD host bridge driver:
   - Attach VMD resources to parent domain's resource tree (Jon Derrick)
   - Set bus resource start to 0 (Keith Busch)

  Microsoft Hyper-V host bridge driver:
   - Add fwnode_handle to x86 pci_sysdata (Jake Oshins)
   - Look up IRQ domain by fwnode_handle (Jake Oshins)
   - Add paravirtual PCI front-end for Microsoft Hyper-V VMs (Jake Oshins)

  NVIDIA Tegra host bridge driver:
   - Add pci_ops.{add,remove}_bus() callbacks (Thierry Reding)
   - Implement ->{add,remove}_bus() callbacks (Thierry Reding)
   - Remove unused struct tegra_pcie.num_ports field (Thierry Reding)
   - Track bus -> CPU mapping (Thierry Reding)
   - Remove misleading PHYS_OFFSET (Thierry Reding)

  Renesas R-Car host bridge driver:
   - Depend on ARCH_RENESAS, not ARCH_SHMOBILE (Simon Horman)

  Synopsys DesignWare host bridge driver:
   - ARC: Add PCI support (Joao Pinto)
   - Add generic dw_pcie_wait_for_link() (Joao Pinto)
   - Add default link up check if sub-driver doesn't override (Joao Pinto)
   - Add driver for prototyping kits based on ARC SDP (Joao Pinto)

  TI Keystone host bridge driver:
   - Defer probing if devm_phy_get() returns -EPROBE_DEFER (Shawn Lin)

  Xilinx AXI host bridge driver:
   - Use of_pci_get_host_bridge_resources() to parse DT (Bharat Kumar Gogada)
   - Remove dependency on ARM-specific struct hw_pci (Bharat Kumar Gogada)
   - Don't call pci_fixup_irqs() on Microblaze (Bharat Kumar Gogada)
   - Update Zynq binding with Microblaze node (Bharat Kumar Gogada)
   - microblaze: Support generic Xilinx AXI PCIe Host Bridge IP driver (Bharat Kumar Gogada)

  Xilinx NWL host bridge driver:
   - Add support for Xilinx NWL PCIe Host Controller (Bharat Kumar Gogada)

  Miscellaneous:
   - Check device_attach() return value always (Bjorn Helgaas)
   - Move pci_set_flags() from asm-generic/pci-bridge.h to linux/pci.h (Bjorn Helgaas)
   - Remove includes of empty asm-generic/pci-bridge.h (Bjorn Helgaas)
   - ARM64: Remove generated include of asm-generic/pci-bridge.h (Bjorn Helgaas)
   - Remove empty asm-generic/pci-bridge.h (Bjorn Helgaas)
   - Remove includes of asm/pci-bridge.h (Bjorn Helgaas)
   - Consolidate PCI DMA constants and interfaces in linux/pci-dma-compat.h (Bjorn Helgaas)
   - unicore32: Remove unused HAVE_ARCH_PCI_SET_DMA_MASK definition (Bjorn Helgaas)
   - Cleanup pci/pcie/Kconfig whitespace (Andreas Ziegler)
   - Include pci/hotplug Kconfig directly from pci/Kconfig (Bjorn Helgaas)
   - Include pci/pcie/Kconfig directly from pci/Kconfig (Bogicevic Sasa)
   - frv: Remove stray pci_{alloc,free}_consistent() declaration (Christoph Hellwig)
   - Move pci_dma_* helpers to common code (Christoph Hellwig)
   - Add PCI_CLASS_SERIAL_USB_DEVICE definition (Heikki Krogerus)
   - Add QEMU top-level IDs for (sub)vendor & device (Robin H. Johnson)
   - Fix broken URL for Dell biosdevname (Naga Venkata Sai Indubhaskar Jupudi)"

* tag 'pci-v4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (94 commits)
  PCI: Add PCI_CLASS_SERIAL_USB_DEVICE definition
  PCI: designware: Add driver for prototyping kits based on ARC SDP
  PCI: designware: Add default link up check if sub-driver doesn't override
  PCI: designware: Add generic dw_pcie_wait_for_link()
  PCI: Cleanup pci/pcie/Kconfig whitespace
  PCI: Simplify pci_create_attr() control flow
  PCI: Don't leak memory if sysfs_create_bin_file() fails
  PCI: Simplify sysfs ROM cleanup
  PCI: Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY
  MIPS: Loongson 3: Keep CPU physical (not virtual) addresses in shadow ROM resource
  MIPS: Loongson 3: Use temporary struct resource * to avoid repetition
  ia64/PCI: Keep CPU physical (not virtual) addresses in shadow ROM resource
  ia64/PCI: Use ioremap() instead of open-coded equivalent
  ia64/PCI: Use temporary struct resource * to avoid repetition
  PCI: Clean up pci_map_rom() whitespace
  PCI: Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs
  PCI: thunder: Add driver for ThunderX-pass{1,2} on-chip devices
  PCI: thunder: Add PCIe host driver for ThunderX processors
  PCI: generic: Expose pci_host_common_probe() for use by other drivers
  PCI: generic: Add pci_host_common_probe(), based on gen_pci_probe()
  ...
2016-03-16 14:45:55 -07:00
Linus Torvalds d09e356ad0 Merge branch 'mm-readonly-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull read-only kernel memory updates from Ingo Molnar:
 "This tree adds two (security related) enhancements to the kernel's
  handling of read-only kernel memory:

   - extend read-only kernel memory to a new class of formerly writable
     kernel data: 'post-init read-only memory' via the __ro_after_init
     attribute, and mark the ARM and x86 vDSO as such read-only memory.

     This kind of attribute can be used for data that requires a once
     per bootup initialization sequence, but is otherwise never modified
     after that point.

     This feature was based on the work by PaX Team and Brad Spengler.

     (by Kees Cook, the ARM vDSO bits by David Brown.)

   - make CONFIG_DEBUG_RODATA always enabled on x86 and remove the
     Kconfig option.  This simplifies the kernel and also signals that
     read-only memory is the default model and a first-class citizen.
     (Kees Cook)"

* 'mm-readonly-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ARM/vdso: Mark the vDSO code read-only after init
  x86/vdso: Mark the vDSO code read-only after init
  lkdtm: Verify that '__ro_after_init' works correctly
  arch: Introduce post-init read-only memory
  x86/mm: Always enable CONFIG_DEBUG_RODATA and remove the Kconfig option
  mm/init: Add 'rodata=off' boot cmdline parameter to disable read-only kernel mappings
  asm-generic: Consolidate mark_rodata_ro()
2016-03-14 16:58:50 -07:00
Alexander Duyck 01cfbad79a ipv4: Update parameters for csum_tcpudp_magic to their original types
This patch updates all instances of csum_tcpudp_magic and
csum_tcpudp_nofold to reflect the types that are usually used as the source
inputs.  For example the protocol field is populated based on nexthdr which
is actually an unsigned 8 bit value.  The length is usually populated based
on skb->len which is an unsigned integer.

This addresses an issue in which the IPv6 function csum_ipv6_magic was
generating a checksum using the full 32b of skb->len while
csum_tcpudp_magic was only using the lower 16 bits.  As a result we could
run into issues when attempting to adjust the checksum as there was no
protocol agnostic way to update it.

With this change the value is still truncated as many architectures use
"(len + proto) << 8", however this truncation only occurs for values
greater than 16776960 in length and as such is unlikely to occur as we stop
the inner headers at ~64K in size.

I did have to make a few minor changes in the arm, mn10300, nios2, and
score versions of the function in order to support these changes as they
were either using things such as an OR to combine the protocol and length,
or were using ntohs to convert the length which would have truncated the
value.

I also updated a few spots in terms of whitespace and type differences for
the addresses.  Most of this was just to make sure all of the definitions
were in sync going forward.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-13 23:55:13 -04:00
Christoph Hellwig bc4b024a8b PCI: Move pci_dma_* helpers to common code
For a long time all architectures implement the pci_dma_* functions using
the generic DMA API, and they all use the same header to do so.

Move this header, pci-dma-compat.h, to include/linux and include it from
the generic pci.h instead of having each arch duplicate this include.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-03-07 10:40:02 -06:00
Arnd Bergmann a1cbaad75a asm-generic: remove old nonatomic-io wrapper files
The two header files got moved to include/linux, and most
users were already converted, this changes the remaining drivers
and removes the files.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Acked-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Yisen Zhuang <yisen.zhuang@huawei.com>
2016-03-01 22:25:17 +01:00
Arnd Bergmann 3c047057d1 asm-generic: default BUG_ON(x) to if(x)BUG()
When CONFIG_BUG is disabled, BUG_ON() will only evaluate the condition,
but will not actually stop the current thread. GCC warns about a couple
of BUG_ON() users where this actually leads to further undefined
behavior:

include/linux/ceph/osdmap.h: In function 'ceph_can_shift_osds':
include/linux/ceph/osdmap.h:54:1: warning: control reaches end of non-void function
fs/ext4/inode.c: In function 'ext4_map_blocks':
fs/ext4/inode.c:548:5: warning: 'retval' may be used uninitialized in this function
drivers/mfd/db8500-prcmu.c: In function 'prcmu_config_clkout':
drivers/mfd/db8500-prcmu.c:762:10: warning: 'div_mask' may be used uninitialized in this function
drivers/mfd/db8500-prcmu.c:769:13: warning: 'mask' may be used uninitialized in this function
drivers/mfd/db8500-prcmu.c:757:7: warning: 'bits' may be used uninitialized in this function
drivers/tty/serial/8250/8250_core.c: In function 'univ8250_release_irq':
drivers/tty/serial/8250/8250_core.c:252:18: warning: 'i' may be used uninitialized in this function
drivers/tty/serial/8250/8250_core.c:235:19: note: 'i' was declared here

There is an obvious conflict of interest here: on the one hand, someone
who disables CONFIG_BUG() will want the kernel to be as small as possible
and doesn't care about printing error messages to a console that nobody
looks at. On the other hand, running into a BUG_ON() condition means that
something has gone wrong, and we probably want to also stop doing things
that might cause data corruption.

This patch picks the second choice, and changes the NOP to BUG(), which
normally stops the execution of the current thread in some form (endless
loop or a trap). This follows the logic we applied in a4b5d580e0 ("bug:
Make BUG() always stop the machine").

For ARM multi_v7_defconfig, the size slightly increases:

section		CONFIG_BUG=y	CONFIG_BUG=n	CONFIG_BUG=n+patch

  .text            8320248   |     8180944   |     8207688
  .rodata          3633720   |     3567144   |     3570648
  __bug_table        32508   |         ---   |         ---
  __modver             692   |        1584   |        2176
  .init.text        558132   |      548300   |      550088
  .exit.text         12380   |       12256   |       12380
  .data            1016672   |     1016064   |     1016128
  Total           14622556   |    14374510   |    14407326

So instead of saving 1.70% of the total image size, we only save 1.48%
by turning off CONFIG_BUG, but in return we can ensure that we don't run
into cases of uninitialized variable or return code uses when something
bad happens. Aside from that, we significantly reduce the number of
warnings in randconfig builds, which makes it easier to fix the warnings
about other problems.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2016-03-01 22:25:12 +01:00
Dan Streetman b82e530290 locking/qspinlock: Move __ARCH_SPIN_LOCK_UNLOCKED to qspinlock_types.h
Move the __ARCH_SPIN_LOCK_UNLOCKED definition from qspinlock.h into
qspinlock_types.h.

The definition of __ARCH_SPIN_LOCK_UNLOCKED comes from the build arch's
include files; but on x86 when CONFIG_QUEUED_SPINLOCKS=y, it just
it's defined in asm-generic/qspinlock.h.  In most cases, this doesn't
matter because linux/spinlock.h includes asm/spinlock.h, which for x86
includes asm-generic/qspinlock.h.  However, any code that only includes
linux/mutex.h will break, because it only includes asm/spinlock_types.h.

For example, this breaks systemtap, which only includes mutex.h.

Signed-off-by: Dan Streetman <dan.streetman@canonical.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <Waiman.Long@hpe.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Streetman <ddstreet@ieee.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>
Link: http://lkml.kernel.org/r/1455907767-17821-1-git-send-email-dan.streetman@canonical.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-29 10:02:43 +01:00
Chen Gang 4e0b6ca9da asm-generic: page.h: Remove useless get_user_page and free_user_page
They are not symmetric with each other, neither are used in real world
(can not be found by grep command in source code root directory), so
remove them.

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2016-02-26 15:24:55 +01:00
Kees Cook c74ba8b348 arch: Introduce post-init read-only memory
One of the easiest ways to protect the kernel from attack is to reduce
the internal attack surface exposed when a "write" flaw is available. By
making as much of the kernel read-only as possible, we reduce the
attack surface.

Many things are written to only during __init, and never changed
again. These cannot be made "const" since the compiler will do the wrong
thing (we do actually need to write to them). Instead, move these items
into a memory region that will be made read-only during mark_rodata_ro()
which happens after all kernel __init code has finished.

This introduces __ro_after_init as a way to mark such memory, and adds
some documentation about the existing __read_mostly marking.

This improves the security of the Linux kernel by marking formerly
read-write memory regions as read-only on a fully booted up system.

Based on work by PaX Team and Brad Spengler.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Brown <david.brown@linaro.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathias Krause <minipli@googlemail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-arch <linux-arch@vger.kernel.org>
Link: http://lkml.kernel.org/r/1455748879-21872-5-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22 08:51:38 +01:00
Linus Torvalds e6a1c1e9dd powerpc fixes for 4.5 #2
- Fix build error on 32-bit with checkpoint restart from Aneesh Kumar
  - Fix dedotify for binutils >= 2.26 from Andreas Schwab
  - Don't trace hcalls on offline CPUs from Denis Kirjanov
  - eeh: Fix stale cached primary bus from Gavin Shan
  - eeh: Fix stale PE primary bus from Gavin Shan
  - mm: Fix Multi hit ERAT cause by recent THP update from Aneesh Kumar K.V
  - ioda: Set "read" permission when "write" is set from Alexey Kardashevskiy
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Merge tag 'powerpc-4.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 - Fix build error on 32-bit with checkpoint restart from Aneesh Kumar
 - Fix dedotify for binutils >= 2.26 from Andreas Schwab
 - Don't trace hcalls on offline CPUs from Denis Kirjanov
 - eeh: Fix stale cached primary bus from Gavin Shan
 - eeh: Fix stale PE primary bus from Gavin Shan
 - mm: Fix Multi hit ERAT cause by recent THP update from Aneesh Kumar K.V
 - ioda: Set "read" permission when "write" is set from Alexey Kardashevskiy

* tag 'powerpc-4.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/ioda: Set "read" permission when "write" is set
  powerpc/mm: Fix Multi hit ERAT cause by recent THP update
  powerpc/powernv: Fix stale PE primary bus
  powerpc/eeh: Fix stale cached primary bus
  powerpc/pseries: Don't trace hcalls on offline CPUs
  powerpc: Fix dedotify for binutils >= 2.26
  powerpc/book3s_32: Fix build error with checkpoint restart
2016-02-20 09:22:11 -08:00
Arnd Bergmann aa6aedb547 gpio: allow setting ARCH_NR_GPIOS from Kconfig
The ARM version of asm/gpio.h basically just contains the same definitions
as the gpiolib version, with the exception of ARCH_NR_GPIOS.

This adds the option for overriding the constant through Kconfig to
the architecture-independent header, so we can remove the ARM specific
file later.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-19 00:22:54 +01:00
Dave Hansen d61172b4b6 mm/core, x86/mm/pkeys: Differentiate instruction fetches
As discussed earlier, we attempt to enforce protection keys in
software.

However, the code checks all faults to ensure that they are not
violating protection key permissions.  It was assumed that all
faults are either write faults where we check PKRU[key].WD (write
disable) or read faults where we check the AD (access disable)
bit.

But, there is a third category of faults for protection keys:
instruction faults.  Instruction faults never run afoul of
protection keys because they do not affect instruction fetches.

So, plumb the PF_INSTR bit down in to the
arch_vma_access_permitted() function where we do the protection
key checks.

We also add a new FAULT_FLAG_INSTRUCTION.  This is because
handle_mm_fault() is not passed the architecture-specific
error_code where we keep PF_INSTR, so we need to encode the
instruction fetch information in to the arch-generic fault
flags.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
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: Rik van Riel <riel@redhat.com>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20160212210224.96928009@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-18 19:46:29 +01:00
Dave Hansen 1b2ee1266e mm/core: Do not enforce PKEY permissions on remote mm access
We try to enforce protection keys in software the same way that we
do in hardware.  (See long example below).

But, we only want to do this when accessing our *own* process's
memory.  If GDB set PKRU[6].AD=1 (disable access to PKEY 6), then
tried to PTRACE_POKE a target process which just happened to have
some mprotect_pkey(pkey=6) memory, we do *not* want to deny the
debugger access to that memory.  PKRU is fundamentally a
thread-local structure and we do not want to enforce it on access
to _another_ thread's data.

This gets especially tricky when we have workqueues or other
delayed-work mechanisms that might run in a random process's context.
We can check that we only enforce pkeys when operating on our *own* mm,
but delayed work gets performed when a random user context is active.
We might end up with a situation where a delayed-work gup fails when
running randomly under its "own" task but succeeds when running under
another process.  We want to avoid that.

To avoid that, we use the new GUP flag: FOLL_REMOTE and add a
fault flag: FAULT_FLAG_REMOTE.  They indicate that we are
walking an mm which is not guranteed to be the same as
current->mm and should not be subject to protection key
enforcement.

Thanks to Jerome Glisse for pointing out this scenario.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <dchinner@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dominik Dingel <dingel@linux.vnet.ibm.com>
Cc: Dominik Vogt <vogt@linux.vnet.ibm.com>
Cc: Eric B Munson <emunson@akamai.com>
Cc: Geliang Tang <geliangtang@163.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jason Low <jason.low2@hp.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Shachar Raindel <raindel@mellanox.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xie XiuQi <xiexiuqi@huawei.com>
Cc: iommu@lists.linux-foundation.org
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-18 19:46:28 +01:00
Dave Hansen 33a709b25a mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys
Today, for normal faults and page table walks, we check the VMA
and/or PTE to ensure that it is compatible with the action.  For
instance, if we get a write fault on a non-writeable VMA, we
SIGSEGV.

We try to do the same thing for protection keys.  Basically, we
try to make sure that if a user does this:

	mprotect(ptr, size, PROT_NONE);
	*ptr = foo;

they see the same effects with protection keys when they do this:

	mprotect(ptr, size, PROT_READ|PROT_WRITE);
	set_pkey(ptr, size, 4);
	wrpkru(0xffffff3f); // access disable pkey 4
	*ptr = foo;

The state to do that checking is in the VMA, but we also
sometimes have to do it on the page tables only, like when doing
a get_user_pages_fast() where we have no VMA.

We add two functions and expose them to generic code:

	arch_pte_access_permitted(pte_flags, write)
	arch_vma_access_permitted(vma, write)

These are, of course, backed up in x86 arch code with checks
against the PTE or VMA's protection key.

But, there are also cases where we do not want to respect
protection keys.  When we ptrace(), for instance, we do not want
to apply the tracer's PKRU permissions to the PTEs from the
process being traced.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dominik Dingel <dingel@linux.vnet.ibm.com>
Cc: Dominik Vogt <vogt@linux.vnet.ibm.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Low <jason.low2@hp.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Shachar Raindel <raindel@mellanox.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/20160212210219.14D5D715@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-18 09:32:44 +01:00
Mark Rutland 3694bd7678 asm-generic: Fix local variable shadow in __set_fixmap_offset
Currently __set_fixmap_offset is a macro function which has a local
variable called 'addr'. If a caller passes a 'phys' parameter which is
derived from a variable also called 'addr', the local variable will
shadow this, and the compiler will complain about the use of an
uninitialized variable. To avoid the issue with namespace clashes,
'addr' is prefixed with a liberal sprinkling of underscores.

Turning __set_fixmap_offset into a static inline breaks the build for
several architectures. Fixing this properly requires updates to a number
of architectures to make them agree on the prototype of __set_fixmap (it
could be done as a subsequent patch series).

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
[catalin.marinas@arm.com: squashed the original function patch and macro fixup]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-16 15:10:44 +00:00
Aneesh Kumar K.V c777e2a8b6 powerpc/mm: Fix Multi hit ERAT cause by recent THP update
With ppc64 we use the deposited pgtable_t to store the hash pte slot
information. We should not withdraw the deposited pgtable_t without
marking the pmd none. This ensure that low level hash fault handling
will skip this huge pte and we will handle them at upper levels.

Recent change to pmd splitting changed the above in order to handle the
race between pmd split and exit_mmap. The race is explained below.

Consider following race:

		CPU0				CPU1
shrink_page_list()
  add_to_swap()
    split_huge_page_to_list()
      __split_huge_pmd_locked()
        pmdp_huge_clear_flush_notify()
	// pmd_none() == true
					exit_mmap()
					  unmap_vmas()
					    zap_pmd_range()
					      // no action on pmd since pmd_none() == true
	pmd_populate()

As result the THP will not be freed. The leak is detected by check_mm():

	BUG: Bad rss-counter state mm:ffff880058d2e580 idx:1 val:512

The above required us to not mark pmd none during a pmd split.

The fix for ppc is to clear the huge pte of _PAGE_USER, so that low
level fault handling code skip this pte. At higher level we do take ptl
lock. That should serialze us against the pmd split. Once the lock is
acquired we do check the pmd again using pmd_same. That should always
return false for us and hence we should retry the access. We do the
pmd_same check in all case after taking plt with
THP (do_huge_pmd_wp_page, do_huge_pmd_numa_page and
huge_pmd_set_accessed)

Also make sure we wait for irq disable section in other cpus to finish
before flipping a huge pte entry with a regular pmd entry. Code paths
like find_linux_pte_or_hugepte depend on irq disable to get
a stable pte_t pointer. A parallel thp split need to make sure we
don't convert a pmd pte to a regular pmd entry without waiting for the
irq disable section to finish.

Fixes: eef1b3ba05 ("thp: implement split_huge_pmd()")
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-02-15 21:10:04 +11:00
Greg Kroah-Hartman 249f3c4fe4 Merge 4.5-rc4 into tty-next
We want the fixes in here, and this resolves a merge error in tty_io.c

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-14 14:36:04 -08:00