Commit Graph

1754 Commits

Author SHA1 Message Date
Linus Torvalds
27efed3e83 Merge branch 'core-watchdog-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull watchddog clean-up and fixes from Thomas Gleixner:
 "The watchdog (hard/softlockup detector) code is pretty much broken in
  its current state. The patch series addresses this by removing all
  duct tape and refactoring it into a workable state.

  The reasons why I ask for inclusion that late in the cycle are:

   1) The code causes lockdep splats vs. hotplug locking which get
      reported over and over. Unfortunately there is no easy fix.

   2) The risk of breakage is minimal because it's already broken

   3) As 4.14 is a long term stable kernel, I prefer to have working
      watchdog code in that and the lockdep issues resolved. I wouldn't
      ask you to pull if 4.14 wouldn't be a LTS kernel or if the
      solution would be easy to backport.

   4) The series was around before the merge window opened, but then got
      delayed due to the UP failure caused by the for_each_cpu()
      surprise which we discussed recently.

  Changes vs. V1:

   - Addressed your review points

   - Addressed the warning in the powerpc code which was discovered late

   - Changed two function names which made sense up to a certain point
     in the series. Now they match what they do in the end.

   - Fixed a 'unused variable' warning, which got not detected by the
     intel robot. I triggered it when trying all possible related config
     combinations manually. Randconfig testing seems not random enough.

  The changes have been tested by and reviewed by Don Zickus and tested
  and acked by Micheal Ellerman for powerpc"

* 'core-watchdog-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  watchdog/core: Put softlockup_threads_initialized under ifdef guard
  watchdog/core: Rename some softlockup_* functions
  powerpc/watchdog: Make use of watchdog_nmi_probe()
  watchdog/core, powerpc: Lock cpus across reconfiguration
  watchdog/core, powerpc: Replace watchdog_nmi_reconfigure()
  watchdog/hardlockup/perf: Fix spelling mistake: "permanetely" -> "permanently"
  watchdog/hardlockup/perf: Cure UP damage
  watchdog/hardlockup: Clean up hotplug locking mess
  watchdog/hardlockup/perf: Simplify deferred event destroy
  watchdog/hardlockup/perf: Use new perf CPU enable mechanism
  watchdog/hardlockup/perf: Implement CPU enable replacement
  watchdog/hardlockup/perf: Implement init time detection of perf
  watchdog/hardlockup/perf: Implement init time perf validation
  watchdog/core: Get rid of the racy update loop
  watchdog/core, powerpc: Make watchdog_nmi_reconfigure() two stage
  watchdog/sysctl: Clean up sysctl variable name space
  watchdog/sysctl: Get rid of the #ifdeffery
  watchdog/core: Clean up header mess
  watchdog/core: Further simplify sysctl handling
  watchdog/core: Get rid of the thread teardown/setup dance
  ...
2017-10-06 08:36:41 -07:00
Helge Deller
8c031ba63f parisc: Unbreak bootloader due to gcc-7 optimizations
gcc-7 optimizes the byte-wise accesses of get_unaligned_le32() into
word-wise accesses if the 32-bit integer output_len is declared as
external. This panics then the bootloader since we don't have the
unaligned access fault trap handler installed during boot time.

Avoid this optimization by declaring output_len as byte-aligned and thus
unbreak the bootloader code.

Additionally, compile the boot code optimized for size.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-09-22 22:26:43 +02:00
Helge Deller
af21b01d11 parisc: Reintroduce option to gzip-compress the kernel
By adding the feature to build the kernel as self-extracting
executeable, the possibility to simply compress the kernel with gzip was
lost.

This patch now reintroduces this possibilty again and leaves it up to
the user to decide how the kernel should be built.

The palo bootloader is able to natively load both formats.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-09-22 22:26:41 +02:00
Helge Deller
606f95e425 parisc: Add HWPOISON page fault handler code
Commit 24587380f6 ("parisc: Add MADV_HWPOISON and MADV_SOFT_OFFLINE") added
the necessary constants to handle hardware-poisoning. Those were needed to
support the page deallocation feature from firmware.

But I completely missed to add the relevant fault handler code. This now
showed up when I ran the madvise07 testcase from the Linux Test Project,
which failed with a kernel BUG at arch/parisc/mm/fault.c:320.

With this patch the parisc kernel now behaves like other platforms and
gives the same kernel syslog warnings when poisoning pages.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-09-22 19:47:17 +02:00
Helge Deller
a7e6601f70 parisc: Move init_per_cpu() into init section
Signed-off-by: Helge Deller <deller@gmx.de>
2017-09-22 19:47:08 +02:00
Helge Deller
ea6976483f parisc: Check if initrd was loaded into broken RAM
While scanning the PDT for reported broken memory modules, warn if the
initrd was coincidentally loaded into bad memory.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-09-22 19:47:00 +02:00
Helge Deller
8d771b143f parisc: Add PDCE_CHECK instruction to HPMC handler
According to the programming note at page 1-31 of the PA 1.1 Firmware
Architecture document, one should use the PDC_INSTR firmware function to
get the instruction that invokes a PDCE_CHECK in the HPMC handler.  This
patch follows this note and sets the instruction which has been a nop up
until now.
Testing on a C3000 and C8000 showed that this firmware call isn't
implemented on those machines, so maybe it's only needed on older ones.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-09-22 19:46:52 +02:00
Helge Deller
77089c5274 parisc: Add wrapper for pdc_instr() firmware function
Signed-off-by: Helge Deller <deller@gmx.de>
2017-09-22 19:46:44 +02:00
Helge Deller
08b8a99b2c parisc: Move start_parisc() into init section
Signed-off-by: Helge Deller <deller@gmx.de>
2017-09-22 19:46:26 +02:00
Helge Deller
e77900abfd parisc: Stop unwinding at start of stack
Check stack pointer if we are reaching the stack end and stop unwinding
if we do. This fixes early backtraces and avoids showing unrealistic
call stacks.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-09-22 19:46:16 +02:00
Thomas Gleixner
47bb4baf7d parisc, watchdog/core: Use lockup_detector_stop()
The broken lockup_detector_suspend/resume() interface is going away. Use
the new lockup_detector_soft_poweroff() interface to stop the watchdog from
the busy looping power off routine.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: linux-parisc@vger.kernel.org
Link: http://lkml.kernel.org/r/20170912194146.407385557@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-14 11:41:03 +02:00
Linus Torvalds
dd198ce714 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull namespace updates from Eric Biederman:
 "Life has been busy and I have not gotten half as much done this round
  as I would have liked. I delayed it so that a minor conflict
  resolution with the mips tree could spend a little time in linux-next
  before I sent this pull request.

  This includes two long delayed user namespace changes from Kirill
  Tkhai. It also includes a very useful change from Serge Hallyn that
  allows the security capability attribute to be used inside of user
  namespaces. The practical effect of this is people can now untar
  tarballs and install rpms in user namespaces. It had been suggested to
  generalize this and encode some of the namespace information
  information in the xattr name. Upon close inspection that makes the
  things that should be hard easy and the things that should be easy
  more expensive.

  Then there is my bugfix/cleanup for signal injection that removes the
  magic encoding of the siginfo union member from the kernel internal
  si_code. The mips folks reported the case where I had used FPE_FIXME
  me is impossible so I have remove FPE_FIXME from mips, while at the
  same time including a return statement in that case to keep gcc from
  complaining about unitialized variables.

  I almost finished the work to get make copy_siginfo_to_user a trivial
  copy to user. The code is available at:

     git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace.git neuter-copy_siginfo_to_user-v3

  But I did not have time/energy to get the code posted and reviewed
  before the merge window opened.

  I was able to see that the security excuse for just copying fields
  that we know are initialized doesn't work in practice there are buggy
  initializations that don't initialize the proper fields in siginfo. So
  we still sometimes copy unitialized data to userspace"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  Introduce v3 namespaced file capabilities
  mips/signal: In force_fcr31_sig return in the impossible case
  signal: Remove kernel interal si_code magic
  fcntl: Don't use ambiguous SIG_POLL si_codes
  prctl: Allow local CAP_SYS_ADMIN changing exe_file
  security: Use user_namespace::level to avoid redundant iterations in cap_capable()
  userns,pidns: Verify the userns for new pid namespaces
  signal/testing: Don't look for __SI_FAULT in userspace
  signal/mips: Document a conflict with SI_USER with SIGFPE
  signal/sparc: Document a conflict with SI_USER with SIGFPE
  signal/ia64: Document a conflict with SI_USER with SIGFPE
  signal/alpha: Document a conflict with SI_USER for SIGTRAP
2017-09-11 18:34:47 -07:00
Babu Moger
4c97a0c8fe arch: define CPU_BIG_ENDIAN for all fixed big endian archs
Patch series "Define CPU_BIG_ENDIAN or warn for inconsistencies", v3.

While working on enabling queued rwlock on SPARC, found this following
code in include/asm-generic/qrwlock.h which uses CONFIG_CPU_BIG_ENDIAN to
clear a byte.

static inline u8 *__qrwlock_write_byte(struct qrwlock *lock)
 {
	return (u8 *)lock + 3 * IS_BUILTIN(CONFIG_CPU_BIG_ENDIAN);
 }

Problem is many of the fixed big endian architectures don't define
CPU_BIG_ENDIAN and clears the wrong byte.

Define CPU_BIG_ENDIAN for all the fixed big endian architecture to fix it.

Also found few more references of this config parameter in
drivers/of/base.c
drivers/of/fdt.c
drivers/tty/serial/earlycon.c
drivers/tty/serial/serial_core.c
Be aware that this may cause regressions if someone has worked-around
problems in the above code already. Remove the work-around.

Here is our original discussion
https://lkml.org/lkml/2017/5/24/620

Link: http://lkml.kernel.org/r/1499358861-179979-2-git-send-email-babu.moger@oracle.com
Signed-off-by: Babu Moger <babu.moger@oracle.com>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Stafford Horne <shorne@gmail.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 18:26:48 -07:00
Linus Torvalds
d34fc1adf0 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - various misc bits

 - DAX updates

 - OCFS2

 - most of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (119 commits)
  mm,fork: introduce MADV_WIPEONFORK
  x86,mpx: make mpx depend on x86-64 to free up VMA flag
  mm: add /proc/pid/smaps_rollup
  mm: hugetlb: clear target sub-page last when clearing huge page
  mm: oom: let oom_reap_task and exit_mmap run concurrently
  swap: choose swap device according to numa node
  mm: replace TIF_MEMDIE checks by tsk_is_oom_victim
  mm, oom: do not rely on TIF_MEMDIE for memory reserves access
  z3fold: use per-cpu unbuddied lists
  mm, swap: don't use VMA based swap readahead if HDD is used as swap
  mm, swap: add sysfs interface for VMA based swap readahead
  mm, swap: VMA based swap readahead
  mm, swap: fix swap readahead marking
  mm, swap: add swap readahead hit statistics
  mm/vmalloc.c: don't reinvent the wheel but use existing llist API
  mm/vmstat.c: fix wrong comment
  selftests/memfd: add memfd_create hugetlbfs selftest
  mm/shmem: add hugetlbfs support to memfd_create()
  mm, devm_memremap_pages: use multi-order radix for ZONE_DEVICE lookups
  mm/vmalloc.c: halve the number of comparisons performed in pcpu_get_vm_areas()
  ...
2017-09-06 20:49:49 -07:00
Rik van Riel
d2cd9ede6e mm,fork: introduce MADV_WIPEONFORK
Introduce MADV_WIPEONFORK semantics, which result in a VMA being empty
in the child process after fork.  This differs from MADV_DONTFORK in one
important way.

If a child process accesses memory that was MADV_WIPEONFORK, it will get
zeroes.  The address ranges are still valid, they are just empty.

If a child process accesses memory that was MADV_DONTFORK, it will get a
segmentation fault, since those address ranges are no longer valid in
the child after fork.

Since MADV_DONTFORK also seems to be used to allow very large programs
to fork in systems with strict memory overcommit restrictions, changing
the semantics of MADV_DONTFORK might break existing programs.

MADV_WIPEONFORK only works on private, anonymous VMAs.

The use case is libraries that store or cache information, and want to
know that they need to regenerate it in the child process after fork.

Examples of this would be:
 - systemd/pulseaudio API checks (fail after fork) (replacing a getpid
   check, which is too slow without a PID cache)
 - PKCS#11 API reinitialization check (mandated by specification)
 - glibc's upcoming PRNG (reseed after fork)
 - OpenSSL PRNG (reseed after fork)

The security benefits of a forking server having a re-inialized PRNG in
every child process are pretty obvious.  However, due to libraries
having all kinds of internal state, and programs getting compiled with
many different versions of each library, it is unreasonable to expect
calling programs to re-initialize everything manually after fork.

A further complication is the proliferation of clone flags, programs
bypassing glibc's functions to call clone directly, and programs calling
unshare, causing the glibc pthread_atfork hook to not get called.

It would be better to have the kernel take care of this automatically.

The patch also adds MADV_KEEPONFORK, to undo the effects of a prior
MADV_WIPEONFORK.

This is similar to the OpenBSD minherit syscall with MAP_INHERIT_ZERO:

    https://man.openbsd.org/minherit.2

[akpm@linux-foundation.org: numerically order arch/parisc/include/uapi/asm/mman.h #defines]
Link: http://lkml.kernel.org/r/20170811212829.29186-3-riel@redhat.com
Signed-off-by: Rik van Riel <riel@redhat.com>
Reported-by: Florian Weimer <fweimer@redhat.com>
Reported-by: Colm MacCártaigh <colm@allcosts.net>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Drewry <wad@chromium.org>
Cc: <linux-api@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:30 -07:00
Mike Kravetz
aafd4562df mm: arch: consolidate mmap hugetlb size encodings
A non-default huge page size can be encoded in the flags argument of the
mmap system call.  The definitions for these encodings are in arch
specific header files.  However, all architectures use the same values.

Consolidate all the definitions in the primary user header file
(uapi/linux/mman.h).  Include definitions for all known huge page sizes.
Use the generic encoding definitions in hugetlb_encode.h as the basis
for these definitions.

Link: http://lkml.kernel.org/r/1501527386-10736-3-git-send-email-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:28 -07:00
Linus Torvalds
aae3dbb477 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Support ipv6 checksum offload in sunvnet driver, from Shannon
    Nelson.

 2) Move to RB-tree instead of custom AVL code in inetpeer, from Eric
    Dumazet.

 3) Allow generic XDP to work on virtual devices, from John Fastabend.

 4) Add bpf device maps and XDP_REDIRECT, which can be used to build
    arbitrary switching frameworks using XDP. From John Fastabend.

 5) Remove UFO offloads from the tree, gave us little other than bugs.

 6) Remove the IPSEC flow cache, from Florian Westphal.

 7) Support ipv6 route offload in mlxsw driver.

 8) Support VF representors in bnxt_en, from Sathya Perla.

 9) Add support for forward error correction modes to ethtool, from
    Vidya Sagar Ravipati.

10) Add time filter for packet scheduler action dumping, from Jamal Hadi
    Salim.

11) Extend the zerocopy sendmsg() used by virtio and tap to regular
    sockets via MSG_ZEROCOPY. From Willem de Bruijn.

12) Significantly rework value tracking in the BPF verifier, from Edward
    Cree.

13) Add new jump instructions to eBPF, from Daniel Borkmann.

14) Rework rtnetlink plumbing so that operations can be run without
    taking the RTNL semaphore. From Florian Westphal.

15) Support XDP in tap driver, from Jason Wang.

16) Add 32-bit eBPF JIT for ARM, from Shubham Bansal.

17) Add Huawei hinic ethernet driver.

18) Allow to report MD5 keys in TCP inet_diag dumps, from Ivan
    Delalande.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1780 commits)
  i40e: point wb_desc at the nvm_wb_desc during i40e_read_nvm_aq
  i40e: avoid NVM acquire deadlock during NVM update
  drivers: net: xgene: Remove return statement from void function
  drivers: net: xgene: Configure tx/rx delay for ACPI
  drivers: net: xgene: Read tx/rx delay for ACPI
  rocker: fix kcalloc parameter order
  rds: Fix non-atomic operation on shared flag variable
  net: sched: don't use GFP_KERNEL under spin lock
  vhost_net: correctly check tx avail during rx busy polling
  net: mdio-mux: add mdio_mux parameter to mdio_mux_init()
  rxrpc: Make service connection lookup always check for retry
  net: stmmac: Delete dead code for MDIO registration
  gianfar: Fix Tx flow control deactivation
  cxgb4: Ignore MPS_TX_INT_CAUSE[Bubble] for T6
  cxgb4: Fix pause frame count in t4_get_port_stats
  cxgb4: fix memory leak
  tun: rename generic_xdp to skb_xdp
  tun: reserve extra headroom only when XDP is set
  net: dsa: bcm_sf2: Configure IMP port TC2QOS mapping
  net: dsa: bcm_sf2: Advertise number of egress queues
  ...
2017-09-06 14:45:08 -07:00
Linus Torvalds
f32c9e059e Merge branch 'parisc-4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc updates from Helge Deller:
 "Major changes include:

   - Full support of the firmware Page Deallocation Table with
     MADV_HWPOISON and MADV_SOFT_OFFLINE. A kernel thread scans
     regularily for new bad memory pages.

   - Full support for self-extracting kernel.

   - Added UBSAN support.

   - Lots of section mismatch fixes across all parisc drivers.

   - Added examples for %pF and %pS usage in printk-formats.txt"

* 'parisc-4.14-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: (28 commits)
  printk-formats.txt: Add examples for %pF and %pS usage
  parisc: Fix up devices below a PCI-PCI MegaRAID controller bridge
  parisc/core: Fix section mismatches
  parisc/ipmi_si_intf: Fix section mismatches on parisc platform
  parisc/input/hilkbd: Fix section mismatches
  parisc/net/lasi_82596: Fix section mismatches
  parisc/serio: Fix section mismatches in gscps2 and hp_sdc drivers
  parisc: Fix section mismatches in parisc core drivers
  parisc/parport_gsc: Fix section mismatches
  parisc/scsi/lasi700: Fix section mismatches
  parisc/scsi/zalon: Fix section mismatches
  parisc/8250_gsc: Fix section mismatches
  parisc/mux: Fix section mismatches
  parisc/sticore: Fix section mismatches
  parisc/harmony: Fix section mismatches
  parisc: Wire up support for self-extracting kernel
  parisc: Make existing core files reuseable for bootloader
  parisc: Add core code for self-extracting kernel
  parisc: Enable UBSAN support
  parisc/random: Add machine specific randomness
  ...
2017-09-05 09:37:11 -07:00
Linus Torvalds
5f82e71a00 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:

 - Add 'cross-release' support to lockdep, which allows APIs like
   completions, where it's not the 'owner' who releases the lock, to be
   tracked. It's all activated automatically under
   CONFIG_PROVE_LOCKING=y.

 - Clean up (restructure) the x86 atomics op implementation to be more
   readable, in preparation of KASAN annotations. (Dmitry Vyukov)

 - Fix static keys (Paolo Bonzini)

 - Add killable versions of down_read() et al (Kirill Tkhai)

 - Rework and fix jump_label locking (Marc Zyngier, Paolo Bonzini)

 - Rework (and fix) tlb_flush_pending() barriers (Peter Zijlstra)

 - Remove smp_mb__before_spinlock() and convert its usages, introduce
   smp_mb__after_spinlock() (Peter Zijlstra)

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits)
  locking/lockdep/selftests: Fix mixed read-write ABBA tests
  sched/completion: Avoid unnecessary stack allocation for COMPLETION_INITIALIZER_ONSTACK()
  acpi/nfit: Fix COMPLETION_INITIALIZER_ONSTACK() abuse
  locking/pvqspinlock: Relax cmpxchg's to improve performance on some architectures
  smp: Avoid using two cache lines for struct call_single_data
  locking/lockdep: Untangle xhlock history save/restore from task independence
  locking/refcounts, x86/asm: Disable CONFIG_ARCH_HAS_REFCOUNT for the time being
  futex: Remove duplicated code and fix undefined behaviour
  Documentation/locking/atomic: Finish the document...
  locking/lockdep: Fix workqueue crossrelease annotation
  workqueue/lockdep: 'Fix' flush_work() annotation
  locking/lockdep/selftests: Add mixed read-write ABBA tests
  mm, locking/barriers: Clarify tlb_flush_pending() barriers
  locking/lockdep: Make CONFIG_LOCKDEP_CROSSRELEASE and CONFIG_LOCKDEP_COMPLETIONS truly non-interactive
  locking/lockdep: Explicitly initialize wq_barrier::done::map
  locking/lockdep: Rename CONFIG_LOCKDEP_COMPLETE to CONFIG_LOCKDEP_COMPLETIONS
  locking/lockdep: Reword title of LOCKDEP_CROSSRELEASE config
  locking/lockdep: Make CONFIG_LOCKDEP_CROSSRELEASE part of CONFIG_PROVE_LOCKING
  locking/refcounts, x86/asm: Implement fast refcount overflow protection
  locking/lockdep: Fix the rollback and overwrite detection logic in crossrelease
  ...
2017-09-04 11:52:29 -07:00
Varsha Rao
9efdb14f76 net: Remove CONFIG_NETFILTER_DEBUG and _ASSERT() macros.
This patch removes CONFIG_NETFILTER_DEBUG and _ASSERT() macros as they
are no longer required. Replace _ASSERT() macros with WARN_ON().

Signed-off-by: Varsha Rao <rvarsha016@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-09-04 13:25:20 +02:00
Jiri Slaby
30d6e0a419 futex: Remove duplicated code and fix undefined behaviour
There is code duplicated over all architecture's headers for
futex_atomic_op_inuser. Namely op decoding, access_ok check for uaddr,
and comparison of the result.

Remove this duplication and leave up to the arches only the needed
assembly which is now in arch_futex_atomic_op_inuser.

This effectively distributes the Will Deacon's arm64 fix for undefined
behaviour reported by UBSAN to all architectures. The fix was done in
commit 5f16a046f8 (arm64: futex: Fix undefined behaviour with
FUTEX_OP_OPARG_SHIFT usage). Look there for an example dump.

And as suggested by Thomas, check for negative oparg too, because it was
also reported to cause undefined behaviour report.

Note that s390 removed access_ok check in d12a29703 ("s390/uaccess:
remove pointless access_ok() checks") as access_ok there returns true.
We introduce it back to the helper for the sake of simplicity (it gets
optimized away anyway).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> [s390]
Acked-by: Chris Metcalf <cmetcalf@mellanox.com> [for tile]
Reviewed-by: Darren Hart (VMware) <dvhart@infradead.org>
Reviewed-by: Will Deacon <will.deacon@arm.com> [core/arm64]
Cc: linux-mips@linux-mips.org
Cc: Rich Felker <dalias@libc.org>
Cc: linux-ia64@vger.kernel.org
Cc: linux-sh@vger.kernel.org
Cc: peterz@infradead.org
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: sparclinux@vger.kernel.org
Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux-s390@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: linux-hexagon@vger.kernel.org
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: linux-snps-arc@lists.infradead.org
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-xtensa@linux-xtensa.org
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: openrisc@lists.librecores.org
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Stafford Horne <shorne@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Richard Henderson <rth@twiddle.net>
Cc: Chris Zankel <chris@zankel.net>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-parisc@vger.kernel.org
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: linux-alpha@vger.kernel.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: "David S. Miller" <davem@davemloft.net>
Link: http://lkml.kernel.org/r/20170824073105.3901-1-jslaby@suse.cz
2017-08-25 22:49:59 +02:00
Helge Deller
6c706b93b0 parisc/core: Fix section mismatches
Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:37 +02:00
Helge Deller
b6adc16e08 parisc: Wire up support for self-extracting kernel
Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:35 +02:00
Helge Deller
f5213b2c40 parisc: Make existing core files reuseable for bootloader
Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:35 +02:00
Helge Deller
2f3c7b8137 parisc: Add core code for self-extracting kernel
Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:35 +02:00
Helge Deller
e35a2ce692 parisc: Enable UBSAN support
Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:34 +02:00
Helge Deller
1ed4714fba parisc/random: Add machine specific randomness
Add some machine-specific information like values of cr16 cycle counter,
machine-specific software ID and machine model to the random generator.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:34 +02:00
John David Anglin
d2883fa1a6 parisc: Optimize switch_mm
We only need to switch contexts when prev != next, and we don't need to
disable interrupts to do the check.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:34 +02:00
Helge Deller
42593e7000 parisc: Drop MADV_SPACEAVAIL, MADV_VPS_PURGE and MADV_VPS_INHERIT
Those aren't used or implemented anywhere in Linux.

Furthermore, MADV_SPACEAVAIL seems to be a HP-UX related flag which is
implemented as null operation in HP-UX. And since we don't support running
HP-UX binaries there is no need to keep it.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:34 +02:00
Helge Deller
8b5bdd850d parisc: Static initialization of pcxl_res_lock spinlock
Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:34 +02:00
Helge Deller
da3dc73ef6 parisc: Drop exception_data struct
Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:33 +02:00
Helge Deller
76cffeb6cc parisc: Static initialization of spinlocks in perf and unwind code
While testing UBSAN I saw this BUG:
 BUG: spinlock bad magic on CPU#0, swapper/0
in unwind code. Let's avoid that by static initialization.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:33 +02:00
Helge Deller
54ac8fcbd6 parisc: PDT: Add full support for memory failure via Page Deallocation Table (PDT)
This patch adds full support to read PDT info on all machine types.  At bootup
the PDT is read and bad memory excluded from usage via memblock_reserve().

Later in the boot process a kernel thread is started (kpdtd) which regularily
checks firmare for new reported bad memory and tries to soft offline pages in
case of correctable errors and to kill processes and exclude such memory in
case of uncorrectable errors via memory_failure().

Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:33 +02:00
Helge Deller
8a5aa00e6b parisc: PDT/firmware: Add support to read PDT on older PAT-machines
Older machines with a PAT firmware (e.g. the rp5470) return their Page
Deallocation Table (PDT) info per cell via the PDC_PAT_MEM_PD_INFO PDC call.
This patch adds the necessary structures and wrappers to call firmware.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:33 +02:00
Helge Deller
24587380f6 parisc: Add MADV_HWPOISON and MADV_SOFT_OFFLINE
Add the missing MADV_HWPOISON (100) and MADV_SOFT_OFFLINE (101) defines which
are needed for an upcoming patch which adds page-deallocation for parisc.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-08-22 16:34:33 +02:00
Ingo Molnar
94edf6f3c2 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

 - Removal of spin_unlock_wait()
 - SRCU updates
 - Torture-test updates
 - Documentation updates
 - Miscellaneous fixes
 - CPU-hotplug fixes
 - Miscellaneous non-RCU fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-21 09:45:19 +02:00
Paul E. McKenney
952111d7db arch: Remove spin_unlock_wait() arch-specific definitions
There is no agreed-upon definition of spin_unlock_wait()'s semantics,
and it appears that all callers could do just as well with a lock/unlock
pair.  This commit therefore removes the underlying arch-specific
arch_spin_unlock_wait() for all architectures providing them.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: <linux-arch@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Andrea Parri <parri.andrea@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
2017-08-17 08:08:59 -07:00
Peter Zijlstra
9d664c0aec locking/atomic: Fix atomic_set_release() for 'funny' architectures
Those architectures that have a special atomic_set implementation also
need a special atomic_set_release(), because for the very same reason
WRITE_ONCE() is broken for them, smp_store_release() is too.

The vast majority is architectures that have spinlock hash based atomic
implementation except hexagon which seems to have a hardware 'feature'.

The spinlock based atomics should be SC, that is, none of them appear to
place extra barriers in atomic_cmpxchg() or any of the other SC atomic
primitives and therefore seem to rely on their spinlock implementation
being SC (I did not fully validate all that).

Therefore, the normal atomic_set() is SC and can be used at
atomic_set_release().

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Chris Metcalf <cmetcalf@mellanox.com> [for tile]
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: davem@davemloft.net
Cc: james.hogan@imgtec.com
Cc: jejb@parisc-linux.org
Cc: rkuo@codeaurora.org
Cc: vgupta@synopsys.com
Link: http://lkml.kernel.org/r/20170609110506.yod47flaav3wgoj5@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10 12:28:54 +02:00
David S. Miller
fde6af4729 mlx5-shared-2017-08-07
This series includes some mlx5 updates for both net-next and rdma trees.
 
 From Saeed,
 Core driver updates to allow selectively building the driver with
 or without some large driver components, such as
 	- E-Switch (Ethernet SRIOV support).
 	- Multi-Physical Function Switch (MPFs) support.
 For that we split E-Switch and MPFs functionalities into separate files.
 
 From Erez,
 Delay mlx5_core events when mlx5 interfaces, namely mlx5_ib, registration
 is taking place and until it completes.
 
 From Rabie,
 Increase the maximum supported flow counters.
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Merge tag 'mlx5-shared-2017-08-07' of git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux

Saeed Mahameed says:

====================
mlx5-shared-2017-08-07

This series includes some mlx5 updates for both net-next and rdma trees.

From Saeed,
Core driver updates to allow selectively building the driver with
or without some large driver components, such as
	- E-Switch (Ethernet SRIOV support).
	- Multi-Physical Function Switch (MPFs) support.
For that we split E-Switch and MPFs functionalities into separate files.

From Erez,
Delay mlx5_core events when mlx5 interfaces, namely mlx5_ib, registration
is taking place and until it completes.

From Rabie,
Increase the maximum supported flow counters.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-07 10:42:09 -07:00
Willem de Bruijn
76851d1212 sock: add SOCK_ZEROCOPY sockopt
The send call ignores unknown flags. Legacy applications may already
unwittingly pass MSG_ZEROCOPY. Continue to ignore this flag unless a
socket opts in to zerocopy.

Introduce socket option SO_ZEROCOPY to enable MSG_ZEROCOPY processing.
Processes can also query this socket option to detect kernel support
for the feature. Older kernels will return ENOPROTOOPT.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-03 21:37:29 -07:00
Babu Moger
74ad3d28af parisc: Define CONFIG_CPU_BIG_ENDIAN
While working on enabling queued rwlock on SPARC, found this following
code in include/asm-generic/qrwlock.h which uses CONFIG_CPU_BIG_ENDIAN
to clear a byte.

static inline u8 *__qrwlock_write_byte(struct qrwlock *lock)
 {
	return (u8 *)lock + 3 * IS_BUILTIN(CONFIG_CPU_BIG_ENDIAN);
 }

Problem is many of the fixed big endian architectures don't define
CPU_BIG_ENDIAN and clears the wrong byte.

Define CPU_BIG_ENDIAN for parisc architecture to fix it.

Signed-off-by: Babu Moger <babu.moger@oracle.com>
Signed-off-by: Helge Deller <deller@gmx.de>
2017-07-31 17:51:27 +02:00
Helge Deller
8f8201dfed parisc: Increase thread and stack size to 32kb
Since kernel 4.11 the thread and irq stacks on parisc randomly overflow
the default size of 16k. The reason why stack usage suddenly grew is yet
unknown.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 4.11+
Signed-off-by: Helge Deller <deller@gmx.de>
2017-07-31 08:41:26 +02:00
John David Anglin
13d57093c1 parisc: Handle vma's whose context is not current in flush_cache_range
In testing James' patch to drivers/parisc/pdc_stable.c, I hit the BUG
statement in flush_cache_range() during a system shutdown:

kernel BUG at arch/parisc/kernel/cache.c:595!
CPU: 2 PID: 6532 Comm: kworker/2:0 Not tainted 4.13.0-rc2+ #1
Workqueue: events free_ioctx

 IAOQ[0]: flush_cache_range+0x144/0x148
 IAOQ[1]: flush_cache_page+0x0/0x1a8
 RP(r2): flush_cache_range+0xec/0x148
Backtrace:
 [<00000000402910ac>] unmap_page_range+0x84/0x880
 [<00000000402918f4>] unmap_single_vma+0x4c/0x60
 [<0000000040291a18>] zap_page_range_single+0x110/0x160
 [<0000000040291c34>] unmap_mapping_range+0x174/0x1a8
 [<000000004026ccd8>] truncate_pagecache+0x50/0xa8
 [<000000004026cd84>] truncate_setsize+0x54/0x70
 [<000000004033d534>] put_aio_ring_file+0x44/0xb0
 [<000000004033d5d8>] aio_free_ring+0x38/0x140
 [<000000004033d714>] free_ioctx+0x34/0xa8
 [<00000000401b0028>] process_one_work+0x1b8/0x4d0
 [<00000000401b04f4>] worker_thread+0x1b4/0x648
 [<00000000401b9128>] kthread+0x1b0/0x208
 [<0000000040150020>] end_fault_vector+0x20/0x28
 [<0000000040639518>] nf_ip_reroute+0x50/0xa8
 [<0000000040638ed0>] nf_ip_route+0x10/0x78
 [<0000000040638c90>] xfrm4_mode_tunnel_input+0x180/0x1f8

CPU: 2 PID: 6532 Comm: kworker/2:0 Not tainted 4.13.0-rc2+ #1
Workqueue: events free_ioctx
Backtrace:
 [<0000000040163bf0>] show_stack+0x20/0x38
 [<0000000040688480>] dump_stack+0xa8/0x120
 [<0000000040163dc4>] die_if_kernel+0x19c/0x2b0
 [<0000000040164d0c>] handle_interruption+0xa24/0xa48

This patch modifies flush_cache_range() to handle non current contexts.
In as much as this occurs infrequently, the simplest approach is to
flush the entire cache when this happens.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Helge Deller <deller@gmx.de>
2017-07-31 08:22:33 +02:00
John David Anglin
56008c04eb parisc: Extend disabled preemption in copy_user_page
It's always bothered me that we only disable preemption in
copy_user_page around the call to flush_dcache_page_asm.
This patch extends this to after the copy.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Helge Deller <deller@gmx.de>
2017-07-25 23:36:54 +02:00
John David Anglin
ae7a609c34 parisc: Prevent TLB speculation on flushed pages on CPUs that only support equivalent aliases
Helge noticed that we flush the TLB page in flush_cache_page but not in
flush_cache_range or flush_cache_mm.

For a long time, we have had random segmentation faults building
packages on machines with PA8800/8900 processors.  These machines only
support equivalent aliases.  We don't see these faults on machines that
don't require strict coherency.  So, it appears TLB speculation
sometimes leads to cache corruption on machines that require coherency.

This patch adds TLB flushes to flush_cache_range and flush_cache_mm when
coherency is required.  We only flush the TLB in flush_cache_page when
coherency is required.

The patch also optimizes flush_cache_range.  It turns out we always have
the right context to use flush_user_dcache_range_asm and
flush_user_icache_range_asm.

The patch has been tested for some time on rp3440, rp3410 and A500-44.
It's been boot tested on c8000.  No random segmentation faults were
observed during testing.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Helge Deller <deller@gmx.de>
2017-07-25 23:36:53 +02:00
Helge Deller
56188832a5 parisc: Suspend lockup detectors before system halt
Some machines can't power off the machine, so disable the lockup detectors to
avoid this watchdog BUG to show up every few seconds:
watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [systemd-shutdow:1]

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: stable@vger.kernel.org # 4.9+
2017-07-25 21:43:38 +02:00
Helge Deller
c46bafc4d2 parisc: Show DIMM slot number which holds broken memory module
The Page Deallocation Table (PDT) holds the physical addresses of all broken
memory addresses. With the physical address we now are able to show which DIMM
slot (e.g. 1a, 3c) actually holds the broken memory module so that users are
able to replace it.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-07-25 21:43:10 +02:00
Helge Deller
25a9b76597 parisc: Add function to return DIMM slot of physical address
Add a firmware wrapper function, which asks PDC firmware for the DIMM slot of a
physical address. This is needed to show users which DIMM module needs
replacement in case a broken DIMM was encountered.

Signed-off-by: Helge Deller <deller@gmx.de>
2017-07-25 19:28:37 +02:00
Helge Deller
f520e55241 parisc: Fix crash when calling PDC_PAT_MEM PDT firmware function
Commit c9c2877d08 ("parisc: Add Page Deallocation Table (PDT) support")
introduced the pdc_pat_mem_read_pd_pdt() firmware helper function, which
crashed the system because it trashed the stack if the
pdc_pat_mem_read_pd_retinfo struct was located on the stack (and which is
in size less than the required 32 64-bit values).

Fix it by using the pdc_result struct instead when calling firmware and copy
the return values back into the result struct when finished sucessfully.

While debugging this code I noticed that the pdc_type wasn't set correctly
either, so let's fix that too.

Fixes: c9c2877d08 ("parisc: Add Page Deallocation Table (PDT) support")
Signed-off-by: Helge Deller <deller@gmx.de>
2017-07-25 18:24:39 +02:00
Eric W. Biederman
cc731525f2 signal: Remove kernel interal si_code magic
struct siginfo is a union and the kernel since 2.4 has been hiding a union
tag in the high 16bits of si_code using the values:
__SI_KILL
__SI_TIMER
__SI_POLL
__SI_FAULT
__SI_CHLD
__SI_RT
__SI_MESGQ
__SI_SYS

While this looks plausible on the surface, in practice this situation has
not worked well.

- Injected positive signals are not copied to user space properly
  unless they have these magic high bits set.

- Injected positive signals are not reported properly by signalfd
  unless they have these magic high bits set.

- These kernel internal values leaked to userspace via ptrace_peek_siginfo

- It was possible to inject these kernel internal values and cause the
  the kernel to misbehave.

- Kernel developers got confused and expected these kernel internal values
  in userspace in kernel self tests.

- Kernel developers got confused and set si_code to __SI_FAULT which
  is SI_USER in userspace which causes userspace to think an ordinary user
  sent the signal and that it was not kernel generated.

- The values make it impossible to reorganize the code to transform
  siginfo_copy_to_user into a plain copy_to_user.  As si_code must
  be massaged before being passed to userspace.

So remove these kernel internal si codes and make the kernel code simpler
and more maintainable.

To replace these kernel internal magic si_codes introduce the helper
function siginfo_layout, that takes a signal number and an si_code and
computes which union member of siginfo is being used.  Have
siginfo_layout return an enumeration so that gcc will have enough
information to warn if a switch statement does not handle all of union
members.

A couple of architectures have a messed up ABI that defines signal
specific duplications of SI_USER which causes more special cases in
siginfo_layout than I would like.  The good news is only problem
architectures pay the cost.

Update all of the code that used the previous magic __SI_ values to
use the new SIL_ values and to call siginfo_layout to get those
values.  Escept where not all of the cases are handled remove the
defaults in the switch statements so that if a new case is missed in
the future the lack will show up at compile time.

Modify the code that copies siginfo si_code to userspace to just copy
the value and not cast si_code to a short first.  The high bits are no
longer used to hold a magic union member.

Fixup the siginfo header files to stop including the __SI_ values in
their constants and for the headers that were missing it to properly
update the number of si_codes for each signal type.

The fixes to copy_siginfo_from_user32 implementations has the
interesting property that several of them perviously should never have
worked as the __SI_ values they depended up where kernel internal.
With that dependency gone those implementations should work much
better.

The idea of not passing the __SI_ values out to userspace and then
not reinserting them has been tested with criu and criu worked without
changes.

Ref: 2.4.0-test1
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2017-07-24 14:30:28 -05:00