Commit Graph

4575 Commits

Author SHA1 Message Date
Linus Torvalds e1ba1c99da Merge tag 'riscv-for-linus-4.15-rc2_cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/linux
Pull RISC-V cleanups and ABI fixes from Palmer Dabbelt:
 "This contains a handful of small cleanups that are a result of
  feedback that didn't make it into our original patch set, either
  because the feedback hadn't been given yet, I missed the original
  emails, or we weren't ready to submit the changes yet.

  I've been maintaining the various cleanup patch sets I have as their
  own branches, which I then merged together and signed. Each merge
  commit has a short summary of the changes, and each branch is based on
  your latest tag (4.15-rc1, in this case). If this isn't the right way
  to do this then feel free to suggest something else, but it seems sane
  to me.

  Here's a short summary of the changes, roughly in order of how
  interesting they are.

   - libgcc.h has been moved from include/lib, where it's the only
     member, to include/linux. This is meant to avoid tab completion
     conflicts.

   - VDSO entries for clock_get/gettimeofday/getcpu have been added.
     These are simple syscalls now, but we want to let glibc use them
     from the start so we can make them faster later.

   - A VDSO entry for instruction cache flushing has been added so
     userspace can flush the instruction cache.

   - The VDSO symbol versions for __vdso_cmpxchg{32,64} have been
     removed, as those VDSO entries don't actually exist.

   - __io_writes has been corrected to respect the given type.

   - A new READ_ONCE in arch_spin_is_locked().

   - __test_and_op_bit_ord() is now actually ordered.

   - Various small fixes throughout the tree to enable allmodconfig to
     build cleanly.

   - Removal of some dead code in our atomic support headers.

   - Improvements to various comments in our atomic support headers"

* tag 'riscv-for-linus-4.15-rc2_cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/linux: (23 commits)
  RISC-V: __io_writes should respect the length argument
  move libgcc.h to include/linux
  RISC-V: Clean up an unused include
  RISC-V: Allow userspace to flush the instruction cache
  RISC-V: Flush I$ when making a dirty page executable
  RISC-V: Add missing include
  RISC-V: Use define for get_cycles like other architectures
  RISC-V: Provide stub of setup_profiling_timer()
  RISC-V: Export some expected symbols for modules
  RISC-V: move empty_zero_page definition to C and export it
  RISC-V: io.h: type fixes for warnings
  RISC-V: use RISCV_{INT,SHORT} instead of {INT,SHORT} for asm macros
  RISC-V: use generic serial.h
  RISC-V: remove spin_unlock_wait()
  RISC-V: `sfence.vma` orderes the instruction cache
  RISC-V: Add READ_ONCE in arch_spin_is_locked()
  RISC-V: __test_and_op_bit_ord should be strongly ordered
  RISC-V: Remove smb_mb__{before,after}_spinlock()
  RISC-V: Remove __smp_bp__{before,after}_atomic
  RISC-V: Comment on why {,cmp}xchg is ordered how it is
  ...
2017-12-01 19:39:12 -05:00
Christoph Hellwig 4db2b604c0 move libgcc.h to include/linux
Introducing a new include/lib directory just for this file totally
messes up tab completion for include/linux, which is highly annoying.

Move it to include/linux where we have headers for all kinds of other
lib/ code as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2017-12-01 13:09:40 -08:00
Linus Torvalds ef0010a309 vsprintf: don't use 'restricted_pointer()' when not restricting
Instead, just fall back on the new '%p' behavior which hashes the
pointer.

Otherwise, '%pK' - that was intended to mark a pointer as restricted -
just ends up leaking pointers that a normal '%p' wouldn't leak.  Which
just make the whole thing pointless.

I suspect we should actually get rid of '%pK' entirely, and make it just
work as '%p' regardless, but this is the minimal obvious fix.  People
who actually use 'kptr_restrict' should weigh in on which behavior they
want.

Cc: Tobin Harding <me@tobin.cc>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-29 11:28:09 -08:00
Tobin C. Harding 7b1924a1d9 vsprintf: add printk specifier %px
printk specifier %p now hashes all addresses before printing. Sometimes
we need to see the actual unmodified address. This can be achieved using
%lx but then we face the risk that if in future we want to change the
way the Kernel handles printing of pointers we will have to grep through
the already existent 50 000 %lx call sites. Let's add specifier %px as a
clear, opt-in, way to print a pointer and maintain some level of
isolation from all the other hex integer output within the Kernel.

Add printk specifier %px to print the actual unmodified address.

Signed-off-by: Tobin C. Harding <me@tobin.cc>
2017-11-29 12:13:14 +11:00
Tobin C. Harding ad67b74d24 printk: hash addresses printed with %p
Currently there exist approximately 14 000 places in the kernel where
addresses are being printed using an unadorned %p. This potentially
leaks sensitive information regarding the Kernel layout in memory. Many
of these calls are stale, instead of fixing every call lets hash the
address by default before printing. This will of course break some
users, forcing code printing needed addresses to be updated.

Code that _really_ needs the address will soon be able to use the new
printk specifier %px to print the address.

For what it's worth, usage of unadorned %p can be broken down as
follows (thanks to Joe Perches).

$ git grep -E '%p[^A-Za-z0-9]' | cut -f1 -d"/" | sort | uniq -c
   1084 arch
     20 block
     10 crypto
     32 Documentation
   8121 drivers
   1221 fs
    143 include
    101 kernel
     69 lib
    100 mm
   1510 net
     40 samples
      7 scripts
     11 security
    166 sound
    152 tools
      2 virt

Add function ptr_to_id() to map an address to a 32 bit unique
identifier. Hash any unadorned usage of specifier %p and any malformed
specifiers.

Signed-off-by: Tobin C. Harding <me@tobin.cc>
2017-11-29 12:09:02 +11:00
Tobin C. Harding 57e734423a vsprintf: refactor %pK code out of pointer()
Currently code to handle %pK is all within the switch statement in
pointer(). This is the wrong level of abstraction. Each of the other switch
clauses call a helper function, pK should do the same.

Refactor code out of pointer() to new function restricted_pointer().

Signed-off-by: Tobin C. Harding <me@tobin.cc>
2017-11-29 12:03:24 +11:00
Linus Torvalds 844056fd74 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:

 - The final conversion of timer wheel timers to timer_setup().

   A few manual conversions and a large coccinelle assisted sweep and
   the removal of the old initialization mechanisms and the related
   code.

 - Remove the now unused VSYSCALL update code

 - Fix permissions of /proc/timer_list. I still need to get rid of that
   file completely

 - Rename a misnomed clocksource function and remove a stale declaration

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
  m68k/macboing: Fix missed timer callback assignment
  treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts
  timer: Remove redundant __setup_timer*() macros
  timer: Pass function down to initialization routines
  timer: Remove unused data arguments from macros
  timer: Switch callback prototype to take struct timer_list * argument
  timer: Pass timer_list pointer to callbacks unconditionally
  Coccinelle: Remove setup_timer.cocci
  timer: Remove setup_*timer() interface
  timer: Remove init_timer() interface
  treewide: setup_timer() -> timer_setup() (2 field)
  treewide: setup_timer() -> timer_setup()
  treewide: init_timer() -> setup_timer()
  treewide: Switch DEFINE_TIMER callbacks to struct timer_list *
  s390: cmm: Convert timers to use timer_setup()
  lightnvm: Convert timers to use timer_setup()
  drivers/net: cris: Convert timers to use timer_setup()
  drm/vc4: Convert timers to use timer_setup()
  block/laptop_mode: Convert timers to use timer_setup()
  net/atm/mpc: Avoid open-coded assignment of timer callback function
  ...
2017-11-25 08:37:16 -10:00
Linus Torvalds 14b661ebb6 Merge tag 'for-linus-20171120' of git://git.infradead.org/linux-mtd
Pull MTD updates from Richard Weinberger:
 "General changes:
   -  Unconfuse get_unmapped_area and point/unpoint driver methods
   -  New partition parser: sharpslpart
   -  Kill GENERIC_IO
   -  Various fixes

  NAND changes:
   -  Add a flag to mark NANDs that require 3 address cycles to encode a
      page address
   -  Set a default ECC/free layout when NAND_ECC_NONE is requested
   -  Fix a bug in panic_nand_write()
   -  Another batch of cleanups for the denali driver
   -  Fix PM support in the atmel driver
   -  Remove support for platform data in the omap driver
   -  Fix subpage write in the omap driver
   -  Fix irq handling in the mtk driver
   -  Change link order of mtk_ecc and mtk_nand drivers to speed up boot
      time
   -  Change log level of ECC error messages in the mxc driver
   -  Patch the pxa3xx driver to support Armada 8k platforms
   -  Add BAM DMA support to the qcom driver
   -  Convert gpio-nand to the GPIO desc API
   -  Fix ECC handling in the mt29f driver

  SPI-NOR changes:
   -  Introduce system power management support
   -  New mechanism to select the proper .quad_enable() hook by JEDEC
      ID, when needed, instead of only by manufacturer ID
   -  Add support to new memory parts from Gigadevice, Winbond, Macronix
      and Everspin
   -  Maintainance for Cadence, Intel, Mediatek and STM32 drivers"

*  tag 'for-linus-20171120' of git://git.infradead.org/linux-mtd: (85 commits)
  mtd: Avoid probe failures when mtd->dbg.dfs_dir is invalid
  mtd: sharpslpart: Add sharpslpart partition parser
  mtd: Add sanity checks in mtd_write/read_oob()
  mtd: remove the get_unmapped_area method
  mtd: implement mtd_get_unmapped_area() using the point method
  mtd: chips/map_rom.c: implement point and unpoint methods
  mtd: chips/map_ram.c: implement point and unpoint methods
  mtd: mtdram: properly handle the phys argument in the point method
  mtd: mtdswap: fix spelling mistake: 'TRESHOLD' -> 'THRESHOLD'
  mtd: slram: use memremap() instead of ioremap()
  kconfig: kill off GENERIC_IO option
  mtd: Fix C++ comment in include/linux/mtd/mtd.h
  mtd: constify mtd_partition
  mtd: plat-ram: Replace manual resource management by devm
  mtd: nand: Fix writing mtdoops to nand flash.
  mtd: intel-spi: Add Intel Lewisburg PCH SPI super SKU PCI ID
  mtd: nand: mtk: fix infinite ECC decode IRQ issue
  mtd: spi-nor: Add support for mr25h128
  mtd: nand: mtk: change the compile sequence of mtk_nand.o and mtk_ecc.o
  mtd: spi-nor: enable 4B opcodes for mx66l51235l
  ...
2017-11-22 20:46:06 -10:00
Kees Cook 24ed960abf treewide: Switch DEFINE_TIMER callbacks to struct timer_list *
This changes all DEFINE_TIMER() callbacks to use a struct timer_list
pointer instead of unsigned long. Since the data argument has already been
removed, none of these callbacks are using their argument currently, so
this renames the argument to "unused".

Done using the following semantic patch:

@match_define_timer@
declarer name DEFINE_TIMER;
identifier _timer, _callback;
@@

 DEFINE_TIMER(_timer, _callback);

@change_callback depends on match_define_timer@
identifier match_define_timer._callback;
type _origtype;
identifier _origarg;
@@

 void
-_callback(_origtype _origarg)
+_callback(struct timer_list *unused)
 { ... }

Signed-off-by: Kees Cook <keescook@chromium.org>
2017-11-21 15:57:05 -08:00
Linus Torvalds fa7f578076 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:

 - a bit more MM

 - procfs updates

 - dynamic-debug fixes

 - lib/ updates

 - checkpatch

 - epoll

 - nilfs2

 - signals

 - rapidio

 - PID management cleanup and optimization

 - kcov updates

 - sysvipc updates

 - quite a few misc things all over the place

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (94 commits)
  EXPERT Kconfig menu: fix broken EXPERT menu
  include/asm-generic/topology.h: remove unused parent_node() macro
  arch/tile/include/asm/topology.h: remove unused parent_node() macro
  arch/sparc/include/asm/topology_64.h: remove unused parent_node() macro
  arch/sh/include/asm/topology.h: remove unused parent_node() macro
  arch/ia64/include/asm/topology.h: remove unused parent_node() macro
  drivers/pcmcia/sa1111_badge4.c: avoid unused function warning
  mm: add infrastructure for get_user_pages_fast() benchmarking
  sysvipc: make get_maxid O(1) again
  sysvipc: properly name ipc_addid() limit parameter
  sysvipc: duplicate lock comments wrt ipc_addid()
  sysvipc: unteach ids->next_id for !CHECKPOINT_RESTORE
  initramfs: use time64_t timestamps
  drivers/watchdog: make use of devm_register_reboot_notifier()
  kernel/reboot.c: add devm_register_reboot_notifier()
  kcov: update documentation
  Makefile: support flag -fsanitizer-coverage=trace-cmp
  kcov: support comparison operands collection
  kcov: remove pointless current != NULL check
  kernel/panic.c: add TAINT_AUX
  ...
2017-11-17 16:56:17 -08:00
Victor Chibotaru d677a4d601 Makefile: support flag -fsanitizer-coverage=trace-cmp
The flag enables Clang instrumentation of comparison operations
(currently not supported by GCC).  This instrumentation is needed by the
new KCOV device to collect comparison operands.

Link: http://lkml.kernel.org/r/20171011095459.70721-2-glider@google.com
Signed-off-by: Victor Chibotaru <tchibo@google.com>
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Popov <alex.popov@linux.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: <syzkaller@googlegroups.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:04 -08:00
Yury Norov 4441fca0a2 lib: test module for find_*_bit() functions
find_bit functions are widely used in the kernel, including hot paths.
This module tests performance of those functions in 2 typical scenarios:
randomly filled bitmap with relatively equal distribution of set and
cleared bits, and sparse bitmap which has 1 set bit for 500 cleared
bits.

On ThunderX machine:

	 Start testing find_bit() with random-filled bitmap
	find_next_bit:          240043 cycles,  164062 iterations
	find_next_zero_bit:     312848 cycles,  163619 iterations
	find_last_bit:          193748 cycles,  164062 iterations
	find_first_bit:      177720874 cycles,  164062 iterations

	 Start testing find_bit() with sparse bitmap
	find_next_bit:            3633 cycles,     656 iterations
	find_next_zero_bit:     620399 cycles,  327025 iterations
	find_last_bit:            3038 cycles,     656 iterations
	find_first_bit:         691407 cycles,     656 iterations

[arnd@arndb.de: use correct format string for find-bit tests]
  Link: http://lkml.kernel.org/r/20171113135605.3166307-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/20171109140714.13168-1-ynorov@caviumnetworks.com
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Clement Courbet <courbet@google.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:02 -08:00
Davidlohr Bueso 0b548e33e6 lib/rbtree-test: lower default params
Fengguang reported soft lockups while running the rbtree and interval
tree test modules.  The logic for these tests all occur in init phase,
and we currently are pounding with the default values for number of
nodes and number of iterations of each test.  Reduce the latter by two
orders of magnitude.  This does not influence the value of the tests in
that one thousand times by default is enough to get the picture.

Link: http://lkml.kernel.org/r/20171109161715.xai2dtwqw2frhkcm@linux-n805
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:02 -08:00
Liu, Changcheng 2f9b7e08cb lib/nmi_backtrace.c: fix kernel text address leak
Don't leak idle function address in NMI backtrace.

Link: http://lkml.kernel.org/r/20171106165648.GA95243@sofia
Signed-off-by: Liu Changcheng <changcheng.liu@intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:02 -08:00
Stephen Bates 36a3d1dd4e lib/genalloc.c: make the avail variable an atomic_long_t
If the amount of resources allocated to a gen_pool exceeds 2^32 then the
avail atomic overflows and this causes problems when clients try and
borrow resources from the pool.  This is only expected to be an issue on
64 bit systems.

Add the <linux/atomic.h> header to pull in atomic_long* operations.  So
that 32 bit systems continue to use atomic32_t but 64 bit systems can
use atomic64_t.

Link: http://lkml.kernel.org/r/1509033843-25667-1-git-send-email-sbates@raithlin.com
Signed-off-by: Stephen Bates <sbates@raithlin.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: Daniel Mentz <danielmentz@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:02 -08:00
Peter Zijlstra e813a61400 lib/int_sqrt: adjust comments
Our current int_sqrt() is not rough nor any approximation; it calculates
the exact value of: floor(sqrt()).  Document this.

Link: http://lkml.kernel.org/r/20171020164645.001652117@infradead.org
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Anshul Garg <aksgarg1989@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: David Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Michael Davidson <md@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:01 -08:00
Peter Zijlstra f8ae107eef lib/int_sqrt: optimize initial value compute
The initial value (@m) compute is:

	m = 1UL << (BITS_PER_LONG - 2);
	while (m > x)
		m >>= 2;

Which is a linear search for the highest even bit smaller or equal to @x
We can implement this using a binary search using __fls() (or better when
its hardware implemented).

	m = 1UL << (__fls(x) & ~1UL);

Especially for small values of @x; which are the more common arguments
when doing a CDF on idle times; the linear search is near to worst case,
while the binary search of __fls() is a constant 6 (or 5 on 32bit)
branches.

      cycles:                 branches:              branch-misses:

PRE:

hot:   43.633557 +- 0.034373  45.333132 +- 0.002277  0.023529 +- 0.000681
cold: 207.438411 +- 0.125840  45.333132 +- 0.002277  6.976486 +- 0.004219

SOFTWARE FLS:

hot:   29.576176 +- 0.028850  26.666730 +- 0.004511  0.019463 +- 0.000663
cold: 165.947136 +- 0.188406  26.666746 +- 0.004511  6.133897 +- 0.004386

HARDWARE FLS:

hot:   24.720922 +- 0.025161  20.666784 +- 0.004509  0.020836 +- 0.000677
cold: 132.777197 +- 0.127471  20.666776 +- 0.004509  5.080285 +- 0.003874

Averages computed over all values <128k using a LFSR to generate order.
Cold numbers have a LFSR based branch trace buffer 'confuser' ran between
each int_sqrt() invocation.

Link: http://lkml.kernel.org/r/20171020164644.936577234@infradead.org
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Suggested-by: Joe Perches <joe@perches.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Anshul Garg <aksgarg1989@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: David Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Michael Davidson <md@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:01 -08:00
Peter Zijlstra 3f3295709e lib/int_sqrt: optimize small argument
The current int_sqrt() computation is sub-optimal for the case of small
@x.  Which is the interesting case when we're going to do cumulative
distribution functions on idle times, which we assume to be a random
variable, where the target residency of the deepest idle state gives an
upper bound on the variable (5e6ns on recent Intel chips).

In the case of small @x, the compute loop:

	while (m != 0) {
		b = y + m;
		y >>= 1;

		if (x >= b) {
			x -= b;
			y += m;
		}
		m >>= 2;
	}

can be reduced to:

	while (m > x)
		m >>= 2;

Because y==0, b==m and until x>=m y will remain 0.

And while this is computationally equivalent, it runs much faster
because there's less code, in particular less branches.

      cycles:                 branches:              branch-misses:

OLD:

hot:   45.109444 +- 0.044117  44.333392 +- 0.002254  0.018723 +- 0.000593
cold: 187.737379 +- 0.156678  44.333407 +- 0.002254  6.272844 +- 0.004305

PRE:

hot:   67.937492 +- 0.064124  66.999535 +- 0.000488  0.066720 +- 0.001113
cold: 232.004379 +- 0.332811  66.999527 +- 0.000488  6.914634 +- 0.006568

POST:

hot:   43.633557 +- 0.034373  45.333132 +- 0.002277  0.023529 +- 0.000681
cold: 207.438411 +- 0.125840  45.333132 +- 0.002277  6.976486 +- 0.004219

Averages computed over all values <128k using a LFSR to generate order.
Cold numbers have a LFSR based branch trace buffer 'confuser' ran between
each int_sqrt() invocation.

Link: http://lkml.kernel.org/r/20171020164644.876503355@infradead.org
Fixes: 30493cc9dd ("lib/int_sqrt.c: optimize square root algorithm")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Suggested-by: Anshul Garg <aksgarg1989@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Joe Perches <joe@perches.com>
Cc: David Miller <davem@davemloft.net>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Davidson <md@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:01 -08:00
Markus Elfring dc2bf000a2 lib/test: delete five error messages for failed memory allocations
Omit extra messages for a memory allocation failure in these functions.

This issue was detected by using the Coccinelle software.

Link: http://lkml.kernel.org/r/410a4c5a-4ee0-6fcc-969c-103d8e496b78@users.sourceforge.net
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:01 -08:00
Geert Uytterhoeven d6b28e0996 lib: add module support to string tests
Extract the string test code into its own source file, to allow
compiling it either to a loadable module, or built into the kernel.

Fixes: 03270c13c5 ("lib/string.c: add testcases for memset16/32/64")
Link: http://lkml.kernel.org/r/1505397744-3387-1-git-send-email-geert@linux-m68k.org
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:01 -08:00
Randy Dunlap 1f3c790bd5 dynamic-debug-howto: fix optional/omitted ending line number to be LARGE instead of 0
line-range is supposed to treat "1-" as "1-endoffile", so
handle the special case by setting last_lineno to UINT_MAX.

Fixes this error:

  dynamic_debug:ddebug_parse_query: last-line:0 < 1st-line:1
  dynamic_debug:ddebug_exec_query: query parse failed

Link: http://lkml.kernel.org/r/10a6a101-e2be-209f-1f41-54637824788e@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:01 -08:00
Kees Cook 2a8358d8a3 bug: define the "cut here" string in a single place
The "cut here" string is used in a few paths.  Define it in a single
place.

Link: http://lkml.kernel.org/r/1510100869-73751-3-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:01 -08:00
Andi Kleen aaf5dcfb22 kernel debug: support resetting WARN_ONCE for all architectures
Some architectures store the WARN_ONCE state in the flags field of the
bug_entry.  Clear that one too when resetting once state through
/sys/kernel/debug/clear_warn_once

Pointed out by Michael Ellerman

Improves the earlier patch that add clear_warn_once.

[ak@linux.intel.com: add a missing ifdef CONFIG_MODULES]
  Link: http://lkml.kernel.org/r/20171020170633.9593-1-andi@firstfloor.org
[akpm@linux-foundation.org: fix unused var warning]
[akpm@linux-foundation.org: Use 0200 for clear_warn_once file, per mpe]
[akpm@linux-foundation.org: clear BUGFLAG_DONE in clear_once_table(), per mpe]
Link: http://lkml.kernel.org/r/20171019204642.7404-1-andi@firstfloor.org
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:01 -08:00
Miles Chen 3aaabbf1c3 lib/dma-debug.c: fix incorrect pfn calculation
dma-debug reports the following warning:

  WARNING: CPU: 3 PID: 298 at kernel-4.4/lib/dma-debug.c:604
  debug _dma_assert_idle+0x1a8/0x230()
  DMA-API: cpu touching an active dma mapped cacheline [cln=0x00000882300]
  CPU: 3 PID: 298 Comm: vold Tainted: G        W  O    4.4.22+ #1
  Hardware name: MT6739 (DT)
  Call trace:
    debug_dma_assert_idle+0x1a8/0x230
    wp_page_copy.isra.96+0x118/0x520
    do_wp_page+0x4fc/0x534
    handle_mm_fault+0xd4c/0x1310
    do_page_fault+0x1c8/0x394
    do_mem_abort+0x50/0xec

I found that debug_dma_alloc_coherent() and debug_dma_free_coherent()
assume that dma_alloc_coherent() always returns a linear address.

However it's possible that dma_alloc_coherent() returns a non-linear
address.  In this case, page_to_pfn(virt_to_page(virt)) will return an
incorrect pfn.  If the pfn is valid and mapped as a COW page, we will
hit the warning when doing wp_page_copy().

Fix this by calculating pfn for linear and non-linear addresses.

[miles.chen@mediatek.com: v4]
  Link: http://lkml.kernel.org/r/1510872972-23919-1-git-send-email-miles.chen@mediatek.com
Link: http://lkml.kernel.org/r/1506484087-1177-1-git-send-email-miles.chen@mediatek.com
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-17 16:10:00 -08:00
Linus Torvalds 16382e17c0 Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull iov_iter updates from Al Viro:

 - bio_{map,copy}_user_iov() series; those are cleanups - fixes from the
   same pile went into mainline (and stable) in late September.

 - fs/iomap.c iov_iter-related fixes

 - new primitive - iov_iter_for_each_range(), which applies a function
   to kernel-mapped segments of an iov_iter.

   Usable for kvec and bvec ones, the latter does kmap()/kunmap() around
   the callback. _Not_ usable for iovec- or pipe-backed iov_iter; the
   latter is not hard to fix if the need ever appears, the former is by
   design.

   Another related primitive will have to wait for the next cycle - it
   passes page + offset + size instead of pointer + size, and that one
   will be usable for everything _except_ kvec. Unfortunately, that one
   didn't get exposure in -next yet, so...

 - a bit more lustre iov_iter work, including a use case for
   iov_iter_for_each_range() (checksum calculation)

 - vhost/scsi leak fix in failure exit

 - misc cleanups and detritectomy...

* 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (21 commits)
  iomap_dio_actor(): fix iov_iter bugs
  switch ksocknal_lib_recv_...() to use of iov_iter_for_each_range()
  lustre: switch struct ksock_conn to iov_iter
  vhost/scsi: switch to iov_iter_get_pages()
  fix a page leak in vhost_scsi_iov_to_sgl() error recovery
  new primitive: iov_iter_for_each_range()
  lnet_return_rx_credits_locked: don't abuse list_entry
  xen: don't open-code iov_iter_kvec()
  orangefs: remove detritus from struct orangefs_kiocb_s
  kill iov_shorten()
  bio_alloc_map_data(): do bmd->iter setup right there
  bio_copy_user_iov(): saner bio size calculation
  bio_map_user_iov(): get rid of copying iov_iter
  bio_copy_from_iter(): get rid of copying iov_iter
  move more stuff down into bio_copy_user_iov()
  blk_rq_map_user_iov(): move iov_iter_advance() down
  bio_map_user_iov(): get rid of the iov_for_each()
  bio_map_user_iov(): move alignment check into the main loop
  don't rely upon subsequent bio_add_pc_page() calls failing
  ... and with iov_iter_get_pages_alloc() it becomes even simpler
  ...
2017-11-17 12:08:18 -08:00