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  1. 29 Aug, 2017 34 commits
  3. 28 Aug, 2017 6 commits
    • Linus Torvalds's avatar
      page waitqueue: always add new entries at the end · 9c3a815f
      Linus Torvalds authored 
      Commit 3510ca20 ("Minor page waitqueue cleanups") made the page
queue code always add new waiters to the back of the queue, which helps
upcoming patches to batch the wakeups for some horrid loads where the
wait queues grow to thousands of entries.

However, I forgot about the nasrt add_page_wait_queue() special case
code that is only used by the cachefiles code.  That one still continued
to add the new wait queue entries at the beginning of the list.

Fix it, because any sane batched wakeup will require that we don't
suddenly start getting new entries at the beginning of the list that we
already handled in a previous batch.

[ The current code always does the whole list while holding the lock, so
  wait queue ordering doesn't matter for correctness, but even then it's
  better to add later entries at the end from a fairness standpoint ]
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      9c3a815f
    • Tejun Heo's avatar
      cpumask: fix spurious cpumask_of_node() on non-NUMA multi-node configs · b339752d
      Tejun Heo authored 
      When !NUMA, cpumask_of_node(@node) equals cpu_online_mask regardless of
@node.  The assumption seems that if !NUMA, there shouldn't be more than
one node and thus reporting cpu_online_mask regardless of @node is
correct.  However, that assumption was broken years ago to support
DISCONTIGMEM and whether a system has multiple nodes or not is
separately controlled by NEED_MULTIPLE_NODES.

This means that, on a system with !NUMA && NEED_MULTIPLE_NODES,
cpumask_of_node() will report cpu_online_mask for all possible nodes,
indicating that the CPUs are associated with multiple nodes which is an
impossible configuration.

This bug has been around forever but doesn't look like it has caused any
noticeable symptoms.  However, it triggers a WARN recently added to
workqueue to verify NUMA affinity configuration.

Fix it by reporting empty cpumask on non-zero nodes if !NUMA.
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
Reported-and-tested-by: default avatarGeert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      b339752d
    • Alexey Brodkin's avatar
      ARCv2: SMP: Mask only private-per-core IRQ lines on boot at core intc · e8206d2b
      Alexey Brodkin authored 
      Recent commit a8ec3ee8 "arc: Mask individual IRQ lines during core
INTC init" breaks interrupt handling on ARCv2 SMP systems.

That commit masked all interrupts at onset, as some controllers on some
boards (customer as well as internal), would assert interrutps early
before any handlers were installed.  For SMP systems, the masking was
done at each cpu's core-intc.  Later, when the IRQ was actually
requested, it was unmasked, but only on the requesting cpu.

For "common" interrupts, which were wired up from the 2nd level IDU
intc, this was as issue as they needed to be enabled on ALL the cpus
(given that IDU IRQs are by default served Round Robin across cpus)

So fix that by NOT masking "common" interrupts at core-intc, but instead
at the 2nd level IDU intc (latter already being done in idu_of_init())

Fixes: a8ec3ee8 ("arc: Mask individual IRQ lines during core INTC init")
Signed-off-by: default avatarAlexey Brodkin <abrodkin@synopsys.com>
[vgupta: reworked changelog, removed the extraneous idu_irq_mask_raw()]
Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      e8206d2b
    • Helge Deller's avatar
      fs/select: Fix memory corruption in compat_get_fd_set() · 79de3cbe
      Helge Deller authored 
      Commit 464d6242 ("select: switch compat_{get,put}_fd_set() to
compat_{get,put}_bitmap()") changed the calculation on how many bytes
need to be zeroed when userspace handed over a NULL pointer for a fdset
array in the select syscall.

The calculation was changed in compat_get_fd_set() wrongly from
	memset(fdset, 0, ((nr + 1) & ~1)*sizeof(compat_ulong_t));
to
	memset(fdset, 0, ALIGN(nr, BITS_PER_LONG));

The ALIGN(nr, BITS_PER_LONG) calculates the number of _bits_ which need
to be zeroed in the target fdset array (rounded up to the next full bits
for an unsigned long).

But the memset() call expects the number of _bytes_ to be zeroed.

This leads to clearing more memory than wanted (on the stack area or
even at kmalloc()ed memory areas) and to random kernel crashes as we
have seen them on the parisc platform.

The correct change should have been

	memset(fdset, 0, (ALIGN(nr, BITS_PER_LONG) / BITS_PER_LONG) * BYTES_PER_LONG);

which is the same as can be archieved with a call to

	zero_fd_set(nr, fdset).

Fixes: 464d6242 ("select: switch compat_{get,put}_fd_set() to compat_{get,put}_bitmap()"
Acked-by: default avatar: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: default avatarHelge Deller <deller@gmx.de>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      79de3cbe
    • Linus Torvalds's avatar
      Merge tag 'for-linus' of git://linux-c6x.org/git/projects/linux-c6x-upstreaming · 702e9762
      Linus Torvalds authored 
      Pull c6x tweaks from Mark Salter.

* tag 'for-linus' of git://linux-c6x.org/git/projects/linux-c6x-upstreaming:
  c6x: Convert to using %pOF instead of full_name
  c6x: defconfig: Cleanup from old Kconfig options
      702e9762
    • Linus Torvalds's avatar
      Linux 4.13-rc7 · cc4a41fe
      Linus Torvalds authored
      cc4a41fe
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