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  1. 14 Sep, 2012 2 commits
  3. 13 Sep, 2012 21 commits
  5. 11 Sep, 2012 9 commits
  7. 10 Sep, 2012 8 commits
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://git.samba.org/sfrench/cifs-2.6 · e9bd8f16
      Linus Torvalds authored 
      Pull CIFS fixes from Steve French.

* 'for-linus' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Fix endianness conversion
  CIFS: Fix error handling in cifs_push_mandatory_locks
      e9bd8f16
    • Linus Torvalds's avatar
      Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs · 1b0a9069
      Linus Torvalds authored 
      Pull UDF and ext3 fixes from Jan Kara:
 "One UDF data corruption fix and one ext3 fix where we didn't write
  everything to disk on fsync in one corner case."

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  udf: Fix data corruption for files in ICB
  ext3: Fix fdatasync() for files with only i_size changes
      1b0a9069
    • Daniel Vetter's avatar
      drm/i915: set the right gen3 flip_done mode also at resume · 974a3b0f
      Daniel Vetter authored 
      Currently we've only frobbed this bit at irq_init time, but did
not restore it at resume time. Move it to the gen3 clock gating
function to fix this.

Notice while reading through code.

Cc: stable@vger.kernel.org (for 3.5 only)
Reviewed-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
      974a3b0f
    • Linus Torvalds's avatar
      Merge branch 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging · 6562271a
      Linus Torvalds authored 
      Pull i2c subsystem fixes from Jean Delvare.

* 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  i2c-core: Fix for lockdep validator
  i2c-designware: Fix build error if CONFIG_I2C_DESIGNWARE_PLATFORM=y && CONFIG_I2C_DESIGNWARE_PCI=y
  i2c-i801: Add Device IDs for Intel Lynx Point-LP PCH
      6562271a
    • Lai Jiangshan's avatar
      workqueue: fix possible idle worker depletion across CPU hotplug · ee378aa4
      Lai Jiangshan authored 
      To simplify both normal and CPU hotplug paths, worker management is
prevented while CPU hoplug is in progress.  This is achieved by CPU
hotplug holding the same exclusion mechanism used by workers to ensure
there's only one manager per pool.

If someone else seems to be performing the manager role, workers
proceed to execute work items.  CPU hotplug using the same mechanism
can lead to idle worker depletion because all workers could proceed to
execute work items while CPU hotplug is in progress and CPU hotplug
itself wouldn't actually perform the worker management duty - it
doesn't guarantee that there's an idle worker left when it releases
management.

This idle worker depletion, under extreme circumstances, can break
forward-progress guarantee and thus lead to deadlock.

This patch fixes the bug by using separate mechanisms for manager
exclusion among workers and hotplug exclusion.  For manager exclusion,
POOL_MANAGING_WORKERS which was restored by the previous patch is
used.  pool->manager_mutex is now only used for exclusion between the
elected manager and CPU hotplug.  The elected manager won't proceed
without holding pool->manager_mutex.

This ensures that the worker which won the manager position can't skip
managing while CPU hotplug is in progress.  It will block on
manager_mutex and perform management after CPU hotplug is complete.

Note that hotplug may happen while waiting for manager_mutex.  A
manager isn't either on idle or busy list and thus the hoplug code
can't unbind/rebind it.  Make the manager handle its own un/rebinding.

tj: Updated comment and description.
Signed-off-by: default avatarLai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      ee378aa4
    • Linus Torvalds's avatar
      Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux · 5d67f2e8
      Linus Torvalds authored 
      Pull drm fixes from Dave Airlie:
 "Just noticed I hadn't send these out, nothing majorly urgent, I know
  AMD guys have some regression fixes coming soon.

  This contains:
   2 nouveau fixes so it loads on the retina MBP systems properly,
   2 vmwgfx fixes to load the driver earlier, and allow distros config it
   1 error->debug fix in ast
  and Keith was playing with 32-on-64 and decided we may as well stick
  the compat ioctl in all the drivers.  It fixes udl for him."

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/vmwgfx: add MODULE_DEVICE_TABLE so vmwgfx loads at boot
  drm/vmwgfx: allow a kconfig option to choose if fbcon is enabled
  drm: use drm_compat_ioctl for 32-bit apps
  drm/ast: drop debug level on error printk
  drm/nv50-/gpio: initialise to vbios defaults during init
  drm/nvd0/disp: hopefully fix selection of 6/8bpc mode on DP outputs
      5d67f2e8
    • Lai Jiangshan's avatar
      workqueue: restore POOL_MANAGING_WORKERS · 552a37e9
      Lai Jiangshan authored 
      This patch restores POOL_MANAGING_WORKERS which was replaced by
pool->manager_mutex by 60373152 "workqueue: use mutex for global_cwq
manager exclusion".

There's a subtle idle worker depletion bug across CPU hotplug events
and we need to distinguish an actual manager and CPU hotplug
preventing management.  POOL_MANAGING_WORKERS will be used for the
former and manager_mutex the later.

This patch just lays POOL_MANAGING_WORKERS on top of the existing
manager_mutex and doesn't introduce any synchronization changes.  The
next patch will update it.

Note that this patch fixes a non-critical anomaly where
too_many_workers() may return %true spuriously while CPU hotplug is in
progress.  While the issue could schedule idle timer spuriously, it
didn't trigger any actual misbehavior.

tj: Rewrote patch description.
Signed-off-by: default avatarLai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      552a37e9
    • Xiao Guangrong's avatar
      KVM: fix error paths for failed gfn_to_page() calls · 4484141a
      Xiao Guangrong authored 
      This bug was triggered:
[ 4220.198458] BUG: unable to handle kernel paging request at fffffffffffffffe
[ 4220.203907] IP: [<ffffffff81104d85>] put_page+0xf/0x34
......
[ 4220.237326] Call Trace:
[ 4220.237361]  [<ffffffffa03830d0>] kvm_arch_destroy_vm+0xf9/0x101 [kvm]
[ 4220.237382]  [<ffffffffa036fe53>] kvm_put_kvm+0xcc/0x127 [kvm]
[ 4220.237401]  [<ffffffffa03702bc>] kvm_vcpu_release+0x18/0x1c [kvm]
[ 4220.237407]  [<ffffffff81145425>] __fput+0x111/0x1ed
[ 4220.237411]  [<ffffffff8114550f>] ____fput+0xe/0x10
[ 4220.237418]  [<ffffffff81063511>] task_work_run+0x5d/0x88
[ 4220.237424]  [<ffffffff8104c3f7>] do_exit+0x2bf/0x7ca

The test case:

	printf(fmt, ##args);		\
	exit(-1);} while (0)

static int create_vm(void)
{
	int sys_fd, vm_fd;

	sys_fd = open("/dev/kvm", O_RDWR);
	if (sys_fd < 0)
		die("open /dev/kvm fail.\n");

	vm_fd = ioctl(sys_fd, KVM_CREATE_VM, 0);
	if (vm_fd < 0)
		die("KVM_CREATE_VM fail.\n");

	return vm_fd;
}

static int create_vcpu(int vm_fd)
{
	int vcpu_fd;

	vcpu_fd = ioctl(vm_fd, KVM_CREATE_VCPU, 0);
	if (vcpu_fd < 0)
		die("KVM_CREATE_VCPU ioctl.\n");
	printf("Create vcpu.\n");
	return vcpu_fd;
}

static void *vcpu_thread(void *arg)
{
	int vm_fd = (int)(long)arg;

	create_vcpu(vm_fd);
	return NULL;
}

int main(int argc, char *argv[])
{
	pthread_t thread;
	int vm_fd;

	(void)argc;
	(void)argv;

	vm_fd = create_vm();
	pthread_create(&thread, NULL, vcpu_thread, (void *)(long)vm_fd);
	printf("Exit.\n");
	return 0;
}

It caused by release kvm->arch.ept_identity_map_addr which is the
error page.

The parent thread can send KILL signal to the vcpu thread when it was
exiting which stops faulting pages and potentially allocating memory.
So gfn_to_pfn/gfn_to_page may fail at this time

Fixed by checking the page before it is used
Signed-off-by: default avatarXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
      4484141a
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