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  1. 06 11月, 2013 3 次提交
  3. 04 11月, 2013 1 次提交
  5. 01 11月, 2013 1 次提交
  7. 31 10月, 2013 1 次提交
    • G
      percpu: fix this_cpu_sub() subtrahend casting for unsigneds · bd09d9a3
      由 Greg Thelen 提交于 
      this_cpu_sub() is implemented as negation and addition.

This patch casts the adjustment to the counter type before negation to
sign extend the adjustment.  This helps in cases where the counter type
is wider than an unsigned adjustment.  An alternative to this patch is
to declare such operations unsupported, but it seemed useful to avoid
surprises.

This patch specifically helps the following example:
  unsigned int delta = 1
  preempt_disable()
  this_cpu_write(long_counter, 0)
  this_cpu_sub(long_counter, delta)
  preempt_enable()

Before this change long_counter on a 64 bit machine ends with value
0xffffffff, rather than 0xffffffffffffffff.  This is because
this_cpu_sub(pcp, delta) boils down to this_cpu_add(pcp, -delta),
which is basically:
  long_counter = 0 + 0xffffffff

Also apply the same cast to:
  __this_cpu_sub()
  __this_cpu_sub_return()
  this_cpu_sub_return()

All percpu_test.ko passes, especially the following cases which
previously failed:

  l -= ui_one;
  __this_cpu_sub(long_counter, ui_one);
  CHECK(l, long_counter, -1);

  l -= ui_one;
  this_cpu_sub(long_counter, ui_one);
  CHECK(l, long_counter, -1);
  CHECK(l, long_counter, 0xffffffffffffffff);

  ul -= ui_one;
  __this_cpu_sub(ulong_counter, ui_one);
  CHECK(ul, ulong_counter, -1);
  CHECK(ul, ulong_counter, 0xffffffffffffffff);

  ul = this_cpu_sub_return(ulong_counter, ui_one);
  CHECK(ul, ulong_counter, 2);

  ul = __this_cpu_sub_return(ulong_counter, ui_one);
  CHECK(ul, ulong_counter, 1);
Signed-off-by: NGreg Thelen <gthelen@google.com>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      bd09d9a3
  9. 23 10月, 2013 1 次提交
  11. 18 10月, 2013 2 次提交
    • D
      yam: integer underflow in yam_ioctl() · 9e5f1721
      由 Dan Carpenter 提交于 
      We cap bitrate at YAM_MAXBITRATE in yam_ioctl(), but it could also be
negative.  I don't know the impact of using a negative bitrate but let's
prevent it.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      9e5f1721
    • G
      usb: usb_phy_gen: refine conditional declaration of usb_nop_xceiv_register · 94468783
      由 Guenter Roeck 提交于 
      Commit 3fa4d734 (usb: phy: rename nop_usb_xceiv => usb_phy_gen_xceiv)
changed the conditional around the declaration of usb_nop_xceiv_register
from
	#if defined(CONFIG_NOP_USB_XCEIV) ||
		(defined(CONFIG_NOP_USB_XCEIV_MODULE) && defined(MODULE))
to
	#if IS_ENABLED(CONFIG_NOP_USB_XCEIV)

While that looks the same, it is semantically different. The first expression
is true if CONFIG_NOP_USB_XCEIV is built as module and if the including
code is built as module. The second expression is true if code depending on
CONFIG_NOP_USB_XCEIV if built as module or into the kernel.

As a result, the arm:allmodconfig build fails with

arch/arm/mach-omap2/built-in.o: In function `omap3_evm_init':
arch/arm/mach-omap2/board-omap3evm.c:703: undefined reference to
	`usb_nop_xceiv_register'

Fix the problem by reverting to the old conditional.

Cc: Josh Boyer <jwboyer@redhat.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      94468783
  13. 17 10月, 2013 2 次提交
    • J
      mm: memcg: handle non-error OOM situations more gracefully · 49426420
      由 Johannes Weiner 提交于 
      Commit 3812c8c8 ("mm: memcg: do not trap chargers with full
callstack on OOM") assumed that only a few places that can trigger a
memcg OOM situation do not return VM_FAULT_OOM, like optional page cache
readahead.  But there are many more and it's impractical to annotate
them all.

First of all, we don't want to invoke the OOM killer when the failed
allocation is gracefully handled, so defer the actual kill to the end of
the fault handling as well.  This simplifies the code quite a bit for
added bonus.

Second, since a failed allocation might not be the abrupt end of the
fault, the memcg OOM handler needs to be re-entrant until the fault
finishes for subsequent allocation attempts.  If an allocation is
attempted after the task already OOMed, allow it to bypass the limit so
that it can quickly finish the fault and invoke the OOM killer.
Reported-by: NazurIt <azurit@pobox.sk>
Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      49426420
    • O
      usb-storage: add quirk for mandatory READ_CAPACITY_16 · 32c37fc3
      由 Oliver Neukum 提交于 
      Some USB drive enclosures do not correctly report an
overflow condition if they hold a drive with a capacity
over 2TB and are confronted with a READ_CAPACITY_10.
They answer with their capacity modulo 2TB.
The generic layer cannot cope with that. It must be told
to use READ_CAPACITY_16 from the beginning.
Signed-off-by: NOliver Neukum <oneukum@suse.de>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      32c37fc3
  15. 16 10月, 2013 2 次提交
  17. 15 10月, 2013 1 次提交
  19. 11 10月, 2013 6 次提交
  21. 09 10月, 2013 20 次提交