A number of audit hooks make function calls before they determine that
auxilary records do not need to be collected. Do those checks as static
inlines since the most common case is going to be that records are not
needed and we can skip the function call overhead.
Signed-off-by: Eric Paris <eparis@redhat.com>
Every arch calls:
if (unlikely(current->audit_context))
audit_syscall_entry()
which requires knowledge about audit (the existance of audit_context) in
the arch code. Just do it all in static inline in audit.h so that arch's
can remain blissfully ignorant.
Signed-off-by: Eric Paris <eparis@redhat.com>
The audit system previously expected arches calling to audit_syscall_exit to
supply as arguments if the syscall was a success and what the return code was.
Audit also provides a helper AUDITSC_RESULT which was supposed to simplify things
by converting from negative retcodes to an audit internal magic value stating
success or failure. This helper was wrong and could indicate that a valid
pointer returned to userspace was a failed syscall. The fix is to fix the
layering foolishness. We now pass audit_syscall_exit a struct pt_reg and it
in turns calls back into arch code to collect the return value and to
determine if the syscall was a success or failure. We also define a generic
is_syscall_success() macro which determines success/failure based on if the
value is < -MAX_ERRNO. This works for arches like x86 which do not use a
separate mechanism to indicate syscall failure.
We make both the is_syscall_success() and regs_return_value() static inlines
instead of macros. The reason is because the audit function must take a void*
for the regs. (uml calls theirs struct uml_pt_regs instead of just struct
pt_regs so audit_syscall_exit can't take a struct pt_regs). Since the audit
function takes a void* we need to use static inlines to cast it back to the
arch correct structure to dereference it.
The other major change is that on some arches, like ia64, MIPS and ppc, we
change regs_return_value() to give us the negative value on syscall failure.
THE only other user of this macro, kretprobe_example.c, won't notice and it
makes the value signed consistently for the audit functions across all archs.
In arch/sh/kernel/ptrace_64.c I see that we were using regs[9] in the old
audit code as the return value. But the ptrace_64.h code defined the macro
regs_return_value() as regs[3]. I have no idea which one is correct, but this
patch now uses the regs_return_value() function, so it now uses regs[3].
For powerpc we previously used regs->result but now use the
regs_return_value() function which uses regs->gprs[3]. regs->gprs[3] is
always positive so the regs_return_value(), much like ia64 makes it negative
before calling the audit code when appropriate.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: H. Peter Anvin <hpa@zytor.com> [for x86 portion]
Acked-by: Tony Luck <tony.luck@intel.com> [for ia64]
Acked-by: Richard Weinberger <richard@nod.at> [for uml]
Acked-by: David S. Miller <davem@davemloft.net> [for sparc]
Acked-by: Ralf Baechle <ralf@linux-mips.org> [for mips]
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [for ppc]
The audit system likes to collect information about processes that end
abnormally (SIGSEGV) as this may me useful intrusion detection information.
This patch adds audit support to collect information when seccomp forces a
task to exit because of misbehavior in a similar way.
Signed-off-by: Eric Paris <eparis@redhat.com>
* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, reboot: Fix typo in nmi reboot path
x86, NMI: Add to_cpumask() to silence compile warning
x86, NMI: NMI selftest depends on the local apic
x86: Add stack top margin for stack overflow checking
x86, NMI: NMI-selftest should handle the UP case properly
x86: Fix the 32-bit stackoverflow-debug build
x86, NMI: Add knob to disable using NMI IPIs to stop cpus
x86, NMI: Add NMI IPI selftest
x86, reboot: Use NMI instead of REBOOT_VECTOR to stop cpus
x86: Clean up the range of stack overflow checking
x86: Panic on detection of stack overflow
x86: Check stack overflow in detail
* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/numa: Add constraints check for nid parameters
mm, x86: Remove debug_pagealloc_enabled
x86/mm: Initialize high mem before free_all_bootmem()
arch/x86/kernel/e820.c: quiet sparse noise about plain integer as NULL pointer
arch/x86/kernel/e820.c: Eliminate bubble sort from sanitize_e820_map()
x86: Fix mmap random address range
x86, mm: Unify zone_sizes_init()
x86, mm: Prepare zone_sizes_init() for unification
x86, mm: Use max_low_pfn for ZONE_NORMAL on 64-bit
x86, mm: Wrap ZONE_DMA32 with CONFIG_ZONE_DMA32
x86, mm: Use max_pfn instead of highend_pfn
x86, mm: Move zone init from paging_init() on 64-bit
x86, mm: Use MAX_DMA_PFN for ZONE_DMA on 32-bit
* git://git.infradead.org/battery-2.6: (68 commits)
power_supply: Mark da9052 driver as broken
power_supply: Drop usage of nowarn variant of sysfs_create_link()
s3c_adc_battery: Average over more than one adc sample
power_supply: Add DA9052 battery driver
isp1704_charger: Fix missing check
jz4740-battery: Fix signedness bug
power_supply: Assume mains power by default
sbs-battery: Fix devicetree match table
ARM: rx51: Add bq27200 i2c board info
sbs-battery: Change power supply name
devicetree-bindings: Propagate bq20z75->sbs rename to dt bindings
devicetree-bindings: Add vendor entry for Smart Battery Systems
sbs-battery: Rename internals to new name
bq20z75: Rename to sbs-battery
wm97xx_battery: Use DEFINE_MUTEX() for work_lock
max8997_charger: Remove duplicate module.h
lp8727_charger: Some minor fixes for the header
lp8727_charger: Add header file
power_supply: Convert drivers/power/* to use module_platform_driver()
power_supply: Add "unknown" in power supply type
...
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci: (80 commits)
x86/PCI: Expand the x86_msi_ops to have a restore MSIs.
PCI: Increase resource array mask bit size in pcim_iomap_regions()
PCI: DEVICE_COUNT_RESOURCE should be equal to PCI_NUM_RESOURCES
PCI: pci_ids: add device ids for STA2X11 device (aka ConneXT)
PNP: work around Dell 1536/1546 BIOS MMCONFIG bug that breaks USB
x86/PCI: amd: factor out MMCONFIG discovery
PCI: Enable ATS at the device state restore
PCI: msi: fix imbalanced refcount of msi irq sysfs objects
PCI: kconfig: English typo in pci/pcie/Kconfig
PCI/PM/Runtime: make PCI traces quieter
PCI: remove pci_create_bus()
xtensa/PCI: convert to pci_scan_root_bus() for correct root bus resources
x86/PCI: convert to pci_create_root_bus() and pci_scan_root_bus()
x86/PCI: use pci_scan_bus() instead of pci_scan_bus_parented()
x86/PCI: read Broadcom CNB20LE host bridge info before PCI scan
sparc32, leon/PCI: convert to pci_scan_root_bus() for correct root bus resources
sparc/PCI: convert to pci_create_root_bus()
sh/PCI: convert to pci_scan_root_bus() for correct root bus resources
powerpc/PCI: convert to pci_create_root_bus()
powerpc/PCI: split PHB part out of pcibios_map_io_space()
...
Fix up conflicts in drivers/pci/msi.c and include/linux/pci_regs.h due
to the same patches being applied in other branches.
* 'for-linus' of git://selinuxproject.org/~jmorris/linux-security: (32 commits)
ima: fix invalid memory reference
ima: free duplicate measurement memory
security: update security_file_mmap() docs
selinux: Casting (void *) value returned by kmalloc is useless
apparmor: fix module parameter handling
Security: tomoyo: add .gitignore file
tomoyo: add missing rcu_dereference()
apparmor: add missing rcu_dereference()
evm: prevent racing during tfm allocation
evm: key must be set once during initialization
mpi/mpi-mpow: NULL dereference on allocation failure
digsig: build dependency fix
KEYS: Give key types their own lockdep class for key->sem
TPM: fix transmit_cmd error logic
TPM: NSC and TIS drivers X86 dependency fix
TPM: Export wait_for_stat for other vendor specific drivers
TPM: Use vendor specific function for status probe
tpm_tis: add delay after aborting command
tpm_tis: Check return code from getting timeouts/durations
tpm: Introduce function to poll for result of self test
...
Fix up trivial conflict in lib/Makefile due to addition of CONFIG_MPI
and SIGSIG next to CONFIG_DQL addition.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
autofs4: deal with autofs4_write/autofs4_write races
autofs4: catatonic_mode vs. notify_daemon race
autofs4: autofs4_wait() vs. autofs4_catatonic_mode() race
hfsplus: creation of hidden dir on mount can fail
block_dev: Suppress bdev_cache_init() kmemleak warninig
fix shrink_dcache_parent() livelock
coda: switch coda_cnode_make() to sane API as well, clean coda_lookup()
coda: deal correctly with allocation failure from coda_cnode_makectl()
securityfs: fix object creation races
Andrew elucidates:
- First installmeant of MM. We have a HUGE number of MM patches this
time. It's crazy.
- MAINTAINERS updates
- backlight updates
- leds
- checkpatch updates
- misc ELF stuff
- rtc updates
- reiserfs
- procfs
- some misc other bits
* akpm: (124 commits)
user namespace: make signal.c respect user namespaces
workqueue: make alloc_workqueue() take printf fmt and args for name
procfs: add hidepid= and gid= mount options
procfs: parse mount options
procfs: introduce the /proc/<pid>/map_files/ directory
procfs: make proc_get_link to use dentry instead of inode
signal: add block_sigmask() for adding sigmask to current->blocked
sparc: make SA_NOMASK a synonym of SA_NODEFER
reiserfs: don't lock root inode searching
reiserfs: don't lock journal_init()
reiserfs: delay reiserfs lock until journal initialization
reiserfs: delete comments referring to the BKL
drivers/rtc/interface.c: fix alarm rollover when day or month is out-of-range
drivers/rtc/rtc-twl.c: add DT support for RTC inside twl4030/twl6030
drivers/rtc/: remove redundant spi driver bus initialization
drivers/rtc/rtc-jz4740.c: make jz4740_rtc_driver static
drivers/rtc/rtc-mc13xxx.c: make mc13xxx_rtc_idtable static
rtc: convert drivers/rtc/* to use module_platform_driver()
drivers/rtc/rtc-wm831x.c: convert to devm_kzalloc()
drivers/rtc/rtc-wm831x.c: remove unused period IRQ handler
...
alloc_workqueue() currently expects the passed in @name pointer to remain
accessible. This is inconvenient and a bit silly given that the whole wq
is being dynamically allocated. This patch updates alloc_workqueue() and
friends to take printf format string instead of opaque string and matching
varargs at the end. The name is allocated together with the wq and
formatted.
alloc_ordered_workqueue() is converted to a macro to unify varargs
handling with alloc_workqueue(), and, while at it, add comment to
alloc_workqueue().
None of the current in-kernel users pass in string with '%' as constant
name and this change shouldn't cause any problem.
[akpm@linux-foundation.org: use __printf]
Signed-off-by: Tejun Heo <tj@kernel.org>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add support for mount options to restrict access to /proc/PID/
directories. The default backward-compatible "relaxed" behaviour is left
untouched.
The first mount option is called "hidepid" and its value defines how much
info about processes we want to be available for non-owners:
hidepid=0 (default) means the old behavior - anybody may read all
world-readable /proc/PID/* files.
hidepid=1 means users may not access any /proc/<pid>/ directories, but
their own. Sensitive files like cmdline, sched*, status are now protected
against other users. As permission checking done in proc_pid_permission()
and files' permissions are left untouched, programs expecting specific
files' modes are not confused.
hidepid=2 means hidepid=1 plus all /proc/PID/ will be invisible to other
users. It doesn't mean that it hides whether a process exists (it can be
learned by other means, e.g. by kill -0 $PID), but it hides process' euid
and egid. It compicates intruder's task of gathering info about running
processes, whether some daemon runs with elevated privileges, whether
another user runs some sensitive program, whether other users run any
program at all, etc.
gid=XXX defines a group that will be able to gather all processes' info
(as in hidepid=0 mode). This group should be used instead of putting
nonroot user in sudoers file or something. However, untrusted users (like
daemons, etc.) which are not supposed to monitor the tasks in the whole
system should not be added to the group.
hidepid=1 or higher is designed to restrict access to procfs files, which
might reveal some sensitive private information like precise keystrokes
timings:
http://www.openwall.com/lists/oss-security/2011/11/05/3
hidepid=1/2 doesn't break monitoring userspace tools. ps, top, pgrep, and
conky gracefully handle EPERM/ENOENT and behave as if the current user is
the only user running processes. pstree shows the process subtree which
contains "pstree" process.
Note: the patch doesn't deal with setuid/setgid issues of keeping
preopened descriptors of procfs files (like
https://lkml.org/lkml/2011/2/7/368). We rely on that the leaked
information like the scheduling counters of setuid apps doesn't threaten
anybody's privacy - only the user started the setuid program may read the
counters.
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Greg KH <greg@kroah.com>
Cc: Theodore Tso <tytso@MIT.EDU>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: James Morris <jmorris@namei.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This one behaves similarly to the /proc/<pid>/fd/ one - it contains
symlinks one for each mapping with file, the name of a symlink is
"vma->vm_start-vma->vm_end", the target is the file. Opening a symlink
results in a file that point exactly to the same inode as them vma's one.
For example the ls -l of some arbitrary /proc/<pid>/map_files/
| lr-x------ 1 root root 64 Aug 26 06:40 7f8f80403000-7f8f80404000 -> /lib64/libc-2.5.so
| lr-x------ 1 root root 64 Aug 26 06:40 7f8f8061e000-7f8f80620000 -> /lib64/libselinux.so.1
| lr-x------ 1 root root 64 Aug 26 06:40 7f8f80826000-7f8f80827000 -> /lib64/libacl.so.1.1.0
| lr-x------ 1 root root 64 Aug 26 06:40 7f8f80a2f000-7f8f80a30000 -> /lib64/librt-2.5.so
| lr-x------ 1 root root 64 Aug 26 06:40 7f8f80a30000-7f8f80a4c000 -> /lib64/ld-2.5.so
This *helps* checkpointing process in three ways:
1. When dumping a task mappings we do know exact file that is mapped
by particular region. We do this by opening
/proc/$pid/map_files/$address symlink the way we do with file
descriptors.
2. This also helps in determining which anonymous shared mappings are
shared with each other by comparing the inodes of them.
3. When restoring a set of processes in case two of them has a mapping
shared, we map the memory by the 1st one and then open its
/proc/$pid/map_files/$address file and map it by the 2nd task.
Using /proc/$pid/maps for this is quite inconvenient since it brings
repeatable re-reading and reparsing for this text file which slows down
restore procedure significantly. Also as being pointed in (3) it is a way
easier to use top level shared mapping in children as
/proc/$pid/map_files/$address when needed.
[akpm@linux-foundation.org: coding-style fixes]
[gorcunov@openvz.org: make map_files depend on CHECKPOINT_RESTORE]
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Reviewed-by: Vasiliy Kulikov <segoon@openwall.com>
Reviewed-by: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Tejun Heo <tj@kernel.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Prepare the ground for the next "map_files" patch which needs a name of a
link file to analyse.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vasiliy Kulikov <segoon@openwall.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Abstract the code sequence for adding a signal handler's sa_mask to
current->blocked because the sequence is identical for all architectures.
Furthermore, in the past some architectures actually got this code wrong,
so introduce a wrapper that all architectures can use.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
TI's TCA6507 is the LED driver in the GTA04 Openmoko motherboard. The
driver provides full support for brightness levels and hardware blinking.
This driver can drive each of 7 outputs as an LED or a GPIO output,
and provides hardware-assist blinking.
[akpm@linux-foundation.org: fix __mod_i2c_device_table alias]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mpol_equal() logically returns a boolean. Use a bool type to slightly
improve readability.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Stephen Wilson <wilsons@start.ca>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
migrate was doing an rmap_walk with speculative lock-less access on
pagetables. That could lead it to not serializing properly against mremap
PT locks. But a second problem remains in the order of vmas in the
same_anon_vma list used by the rmap_walk.
If vma_merge succeeds in copy_vma, the src vma could be placed after the
dst vma in the same_anon_vma list. That could still lead to migrate
missing some pte.
This patch adds an anon_vma_moveto_tail() function to force the dst vma at
the end of the list before mremap starts to solve the problem.
If the mremap is very large and there are a lots of parents or childs
sharing the anon_vma root lock, this should still scale better than taking
the anon_vma root lock around every pte copy practically for the whole
duration of mremap.
Update: Hugh noticed special care is needed in the error path where
move_page_tables goes in the reverse direction, a second
anon_vma_moveto_tail() call is needed in the error path.
This program exercises the anon_vma_moveto_tail:
===
int main()
{
static struct timeval oldstamp, newstamp;
long diffsec;
char *p, *p2, *p3, *p4;
if (posix_memalign((void **)&p, 2*1024*1024, SIZE))
perror("memalign"), exit(1);
if (posix_memalign((void **)&p2, 2*1024*1024, SIZE))
perror("memalign"), exit(1);
if (posix_memalign((void **)&p3, 2*1024*1024, SIZE))
perror("memalign"), exit(1);
memset(p, 0xff, SIZE);
printf("%p\n", p);
memset(p2, 0xff, SIZE);
memset(p3, 0x77, 4096);
if (memcmp(p, p2, SIZE))
printf("error\n");
p4 = mremap(p+SIZE/2, SIZE/2, SIZE/2, MREMAP_FIXED|MREMAP_MAYMOVE, p3);
if (p4 != p3)
perror("mremap"), exit(1);
p4 = mremap(p4, SIZE/2, SIZE/2, MREMAP_FIXED|MREMAP_MAYMOVE, p+SIZE/2);
if (p4 != p+SIZE/2)
perror("mremap"), exit(1);
if (memcmp(p, p2, SIZE))
printf("error\n");
printf("ok\n");
return 0;
}
===
$ perf probe -a anon_vma_moveto_tail
Add new event:
probe:anon_vma_moveto_tail (on anon_vma_moveto_tail)
You can now use it on all perf tools, such as:
perf record -e probe:anon_vma_moveto_tail -aR sleep 1
$ perf record -e probe:anon_vma_moveto_tail -aR ./anon_vma_moveto_tail
0x7f2ca2800000
ok
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.043 MB perf.data (~1860 samples) ]
$ perf report --stdio
100.00% anon_vma_moveto [kernel.kallsyms] [k] anon_vma_moveto_tail
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Nai Xia <nai.xia@gmail.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Pawel Sikora <pluto@agmk.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The maximum number of dirty pages that exist in the system at any time is
determined by a number of pages considered dirtyable and a user-configured
percentage of those, or an absolute number in bytes.
This number of dirtyable pages is the sum of memory provided by all the
zones in the system minus their lowmem reserves and high watermarks, so
that the system can retain a healthy number of free pages without having
to reclaim dirty pages.
But there is a flaw in that we have a zoned page allocator which does not
care about the global state but rather the state of individual memory
zones. And right now there is nothing that prevents one zone from filling
up with dirty pages while other zones are spared, which frequently leads
to situations where kswapd, in order to restore the watermark of free
pages, does indeed have to write pages from that zone's LRU list. This
can interfere so badly with IO from the flusher threads that major
filesystems (btrfs, xfs, ext4) mostly ignore write requests from reclaim
already, taking away the VM's only possibility to keep such a zone
balanced, aside from hoping the flushers will soon clean pages from that
zone.
Enter per-zone dirty limits. They are to a zone's dirtyable memory what
the global limit is to the global amount of dirtyable memory, and try to
make sure that no single zone receives more than its fair share of the
globally allowed dirty pages in the first place. As the number of pages
considered dirtyable excludes the zones' lowmem reserves and high
watermarks, the maximum number of dirty pages in a zone is such that the
zone can always be balanced without requiring page cleaning.
As this is a placement decision in the page allocator and pages are
dirtied only after the allocation, this patch allows allocators to pass
__GFP_WRITE when they know in advance that the page will be written to and
become dirty soon. The page allocator will then attempt to allocate from
the first zone of the zonelist - which on NUMA is determined by the task's
NUMA memory policy - that has not exceeded its dirty limit.
At first glance, it would appear that the diversion to lower zones can
increase pressure on them, but this is not the case. With a full high
zone, allocations will be diverted to lower zones eventually, so it is
more of a shift in timing of the lower zone allocations. Workloads that
previously could fit their dirty pages completely in the higher zone may
be forced to allocate from lower zones, but the amount of pages that
"spill over" are limited themselves by the lower zones' dirty constraints,
and thus unlikely to become a problem.
For now, the problem of unfair dirty page distribution remains for NUMA
configurations where the zones allowed for allocation are in sum not big
enough to trigger the global dirty limits, wake up the flusher threads and
remedy the situation. Because of this, an allocation that could not
succeed on any of the considered zones is allowed to ignore the dirty
limits before going into direct reclaim or even failing the allocation,
until a future patch changes the global dirty throttling and flusher
thread activation so that they take individual zone states into account.
Test results
15M DMA + 3246M DMA32 + 504 Normal = 3765M memory
40% dirty ratio
16G USB thumb drive
10 runs of dd if=/dev/zero of=disk/zeroes bs=32k count=$((10 << 15))
seconds nr_vmscan_write
(stddev) min| median| max
xfs
vanilla: 549.747( 3.492) 0.000| 0.000| 0.000
patched: 550.996( 3.802) 0.000| 0.000| 0.000
fuse-ntfs
vanilla: 1183.094(53.178) 54349.000| 59341.000| 65163.000
patched: 558.049(17.914) 0.000| 0.000| 43.000
btrfs
vanilla: 573.679(14.015) 156657.000| 460178.000| 606926.000
patched: 563.365(11.368) 0.000| 0.000| 1362.000
ext4
vanilla: 561.197(15.782) 0.000|2725438.000|4143837.000
patched: 568.806(17.496) 0.000| 0.000| 0.000
Signed-off-by: Johannes Weiner <jweiner@redhat.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Tested-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Per-zone dirty limits try to distribute page cache pages allocated for
writing across zones in proportion to the individual zone sizes, to reduce
the likelihood of reclaim having to write back individual pages from the
LRU lists in order to make progress.
This patch:
The amount of dirtyable pages should not include the full number of free
pages: there is a number of reserved pages that the page allocator and
kswapd always try to keep free.
The closer (reclaimable pages - dirty pages) is to the number of reserved
pages, the more likely it becomes for reclaim to run into dirty pages:
+----------+ ---
| anon | |
+----------+ |
| | |
| | -- dirty limit new -- flusher new
| file | | |
| | | |
| | -- dirty limit old -- flusher old
| | |
+----------+ --- reclaim
| reserved |
+----------+
| kernel |
+----------+
This patch introduces a per-zone dirty reserve that takes both the lowmem
reserve as well as the high watermark of the zone into account, and a
global sum of those per-zone values that is subtracted from the global
amount of dirtyable pages. The lowmem reserve is unavailable to page
cache allocations and kswapd tries to keep the high watermark free. We
don't want to end up in a situation where reclaim has to clean pages in
order to balance zones.
Not treating reserved pages as dirtyable on a global level is only a
conceptual fix. In reality, dirty pages are not distributed equally
across zones and reclaim runs into dirty pages on a regular basis.
But it is important to get this right before tackling the problem on a
per-zone level, where the distance between reclaim and the dirty pages is
mostly much smaller in absolute numbers.
[akpm@linux-foundation.org: fix highmem build]
Signed-off-by: Johannes Weiner <jweiner@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Calling alloc_pages_exact_node() means the allocation only passes the
zonelist of a single node into the page allocator. If that node isn't
online, it's zonelist may never have been initialized causing a strange
oops that may not immediately be clear.
I recently debugged an issue where node 0 wasn't online and an allocator
was passing 0 to alloc_pages_exact_node() and it resulted in a NULL
pointer on zonelist->_zoneref. If CONFIG_DEBUG_VM is enabled, though, it
would be nice to catch this a bit earlier.
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
With CONFIG_DEBUG_PAGEALLOC configured, the CPU will generate an exception
on access (read,write) to an unallocated page, which permits us to catch
code which corrupts memory. However the kernel is trying to maximise
memory usage, hence there are usually few free pages in the system and
buggy code usually corrupts some crucial data.
This patch changes the buddy allocator to keep more free/protected pages
and to interlace free/protected and allocated pages to increase the
probability of catching corruption.
When the kernel is compiled with CONFIG_DEBUG_PAGEALLOC,
debug_guardpage_minorder defines the minimum order used by the page
allocator to grant a request. The requested size will be returned with
the remaining pages used as guard pages.
The default value of debug_guardpage_minorder is zero: no change from
current behaviour.
[akpm@linux-foundation.org: tweak documentation, s/flg/flag/]
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We can place this in definitions that we expect the compiler to remove by
dead code elimination. If this assertion fails, we get a nice error
message at build time.
The GCC function attribute error("message") was added in version 4.3, so
we define a new macro __linktime_error(message) to expand to this for
GCC-4.3 and later. This will give us an error diagnostic from the
compiler on the line that fails. For other compilers
__linktime_error(message) expands to nothing, and we have to be content
with a link time error, but at least we will still get a build error.
BUILD_BUG() expands to the undefined function __build_bug_failed() and
will fail at link time if the compiler ever emits code for it. On GCC-4.3
and later, attribute((error())) is used so that the failure will be noted
at compile time instead.
Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: DM <dm.n9107@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Colin Cross reported;
Under the following conditions, __alloc_pages_slowpath can loop forever:
gfp_mask & __GFP_WAIT is true
gfp_mask & __GFP_FS is false
reclaim and compaction make no progress
order <= PAGE_ALLOC_COSTLY_ORDER
These conditions happen very often during suspend and resume,
when pm_restrict_gfp_mask() effectively converts all GFP_KERNEL
allocations into __GFP_WAIT.
The oom killer is not run because gfp_mask & __GFP_FS is false,
but should_alloc_retry will always return true when order is less
than PAGE_ALLOC_COSTLY_ORDER.
In his fix, he avoided retrying the allocation if reclaim made no progress
and __GFP_FS was not set. The problem is that this would result in
GFP_NOIO allocations failing that previously succeeded which would be very
unfortunate.
The big difference between GFP_NOIO and suspend converting GFP_KERNEL to
behave like GFP_NOIO is that normally flushers will be cleaning pages and
kswapd reclaims pages allowing GFP_NOIO to succeed after a short delay.
The same does not necessarily apply during suspend as the storage device
may be suspended.
This patch special cases the suspend case to fail the page allocation if
reclaim cannot make progress and adds some documentation on how
gfp_allowed_mask is currently used. Failing allocations like this may
cause suspend to abort but that is better than a livelock.
[mgorman@suse.de: Rework fix to be suspend specific]
[rientjes@google.com: Move suspended device check to should_alloc_retry]
Reported-by: Colin Cross <ccross@android.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It not exported and now nobody uses it.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The tracing ring-buffer used this function briefly, but not anymore.
Make it local to the writeback code again.
Also, move the function so that no forward declaration needs to be
reintroduced.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Michal Hocko <mhocko@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Ext4 commits for 3.3 merge window
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (32 commits)
ext4: fix undefined behavior in ext4_fill_flex_info()
ext4: make more symbols static
ext4: make local symbol ext4_initxattrs static
jbd2: fix hung processes in jbd2_journal_lock_updates()
ext4: reserve new feature flag codepoints
ext4: Report max_batch_time option correctly
ext4: add missing ext4_resize_end on error paths
ext4: let ext4_group_add() use common code
ext4: let ext4_group_extend() use common code
ext4: add new online resize interface
ext4: add a new function which adds a flex group to a fs
ext4: add a new function which allocates bitmaps and inode tables
ext4: pass verify_reserved_gdb() the number of group decriptors
ext4: add a function which updates the super block during online resizing
ext4: add a function which sets up a block group descriptors of a flex bg
ext4: add a function which sets up group blocks of a flex bg
ext4: add a structure which will be used by 64bit-resize interface
ext4: add a function which adds a new group descriptors to a fs
ext4: add a function which extends a group without checking parameters
ext4: use proper little-endian bitops
...
* 'nfs-for-3.3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv4: Change the default setting of the nfs4_disable_idmapping parameter
NFSv4: Save the owner/group name string when doing open
NFS: Remove pNFS bloat from the generic write path
pnfs-obj: Must return layout on IO error
pnfs-obj: pNFS errors are communicated on iodata->pnfs_error
NFS: Cache state owners after files are closed
NFS: Clean up nfs4_find_state_owners_locked()
NFSv4: include bitmap in nfsv4 get acl data
nfs: fix a minor do_div portability issue
NFSv4.1: cleanup comment and debug printk
NFSv4.1: change nfs4_free_slot parameters for dynamic slots
NFSv4.1: cleanup init and reset of session slot tables
NFSv4.1: fix backchannel slotid off-by-one bug
nfs: fix regression in handling of context= option in NFSv4
NFS - fix recent breakage to NFS error handling.
NFS: Retry mounting NFSROOT
SUNRPC: Clean up the RPCSEC_GSS service ticket requests
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Merge tag 'for-linus-3.3' of git://git.infradead.org/mtd-2.6
MTD pull for 3.3
* tag 'for-linus-3.3' of git://git.infradead.org/mtd-2.6: (113 commits)
mtd: Fix dependency for MTD_DOC200x
mtd: do not use mtd->block_markbad directly
logfs: do not use 'mtd->block_isbad' directly
mtd: introduce mtd_can_have_bb helper
mtd: do not use mtd->suspend and mtd->resume directly
mtd: do not use mtd->lock, unlock and is_locked directly
mtd: do not use mtd->sync directly
mtd: harmonize mtd_writev usage
mtd: do not use mtd->lock_user_prot_reg directly
mtd: mtd->write_user_prot_reg directly
mtd: do not use mtd->read_*_prot_reg directly
mtd: do not use mtd->get_*_prot_info directly
mtd: do not use mtd->read_oob directly
mtd: mtdoops: do not use mtd->panic_write directly
romfs: do not use mtd->get_unmapped_area directly
mtd: do not use mtd->get_unmapped_area directly
mtd: do use mtd->point directly
mtd: introduce mtd_has_oob helper
mtd: mtdcore: export symbols cleanup
mtd: clean-up the default_mtd_writev function
...
Fix up trivial edit/remove conflict in drivers/staging/spectra/lld_mtd.c
* 'drm-core-next' of git://people.freedesktop.org/~airlied/linux: (307 commits)
drm/nouveau/pm: fix build with HWMON off
gma500: silence gcc warnings in mid_get_vbt_data()
drm/ttm: fix condition (and vs or)
drm/radeon: double lock typo in radeon_vm_bo_rmv()
drm/radeon: use after free in radeon_vm_bo_add()
drm/sis|via: don't return stack garbage from free_mem ioctl
drm/radeon/kms: remove pointless CS flags priority struct
drm/radeon/kms: check if vm is supported in VA ioctl
drm: introduce drm_can_sleep and use in intel/radeon drivers. (v2)
radeon: Fix disabling PCI bus mastering on big endian hosts.
ttm: fix agp since ttm tt rework
agp: Fix multi-line warning message whitespace
drm/ttm/dma: Fix accounting error when calling ttm_mem_global_free_page and don't try to free freed pages.
drm/ttm/dma: Only call set_pages_array_wb when the page is not in WB pool.
drm/radeon/kms: sync across multiple rings when doing bo moves v3
drm/radeon/kms: Add support for multi-ring sync in CS ioctl (v2)
drm/radeon: GPU virtual memory support v22
drm: make DRM_UNLOCKED ioctls with their own mutex
drm: no need to hold global mutex for static data
drm/radeon/benchmark: common modes sweep ignores 640x480@32
...
Fix up trivial conflicts in radeon/evergreen.c and vmwgfx/vmwgfx_kms.c
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (64 commits)
Input: tc3589x-keypad - add missing kerneldoc
Input: ucb1400-ts - switch to using dev_xxx() for diagnostic messages
Input: ucb1400_ts - convert to threaded IRQ
Input: ucb1400_ts - drop inline annotations
Input: usb1400_ts - add __devinit/__devexit section annotations
Input: ucb1400_ts - set driver owner
Input: ucb1400_ts - convert to use dev_pm_ops
Input: psmouse - make sure we do not use stale methods
Input: evdev - do not block waiting for an event if fd is nonblock
Input: evdev - if no events and non-block, return EAGAIN not 0
Input: evdev - only allow reading events if a full packet is present
Input: add driver for pixcir i2c touchscreens
Input: samsung-keypad - implement runtime power management support
Input: tegra-kbc - report wakeup key for some platforms
Input: tegra-kbc - add device tree bindings
Input: add driver for AUO In-Cell touchscreens using pixcir ICs
Input: mpu3050 - configure the sampling method
Input: mpu3050 - ensure we enable interrupts
Input: mpu3050 - add of_match table for device-tree probing
Input: sentelic - document the latest hardware
...
Fix up fairly trivial conflicts (device tree matching conflicting with
some independent cleanups) in drivers/input/keyboard/samsung-keypad.c
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (68 commits)
hid-input/battery: add FEATURE quirk
hid-input/battery: remove battery_val
hid-input/battery: power-supply type really *is* a battery
hid-input/battery: make the battery setup common for INPUTs and FEATUREs
hid-input/battery: deal with both FEATURE and INPUT report batteries
hid-input/battery: add quirks for battery
hid-input/battery: remove apparently redundant kmalloc
hid-input: add support for HID devices reporting Battery Strength
HID: hid-multitouch: add support 9 new Xiroku devices
HID: multitouch: add support for 3M 32"
HID: multitouch: add support of Atmel multitouch panels
HID: usbhid: defer LED setting to a workqueue
HID: usbhid: hid-core: submit queued urbs before suspend
HID: usbhid: remove LED_ON
HID: emsff: use symbolic name instead of hardcoded PID constant
HID: Enable HID_QUIRK_MULTI_INPUT for Trio Linker Plus II
HID: Kconfig: fix syntax
HID: introduce proper dependency of HID_BATTERY on POWER_SUPPLY
HID: multitouch: support PixArt optical touch screen
HID: make parser more verbose about parsing errors by default
...
Fix up rename/delete conflict in drivers/hid/hid-hyperv.c (removed in
staging, moved in this branch) and similarly for the rules for same file
in drivers/staging/hv/{Kconfig,Makefile}.
* git://www.linux-watchdog.org/linux-watchdog:
watchdog: omap_wdt.c: fix the WDIOC_GETBOOTSTATUS ioctl if not implemented.
watchdog: new driver for VIA chipsets
watchdog: ath79_wdt: flush register writes
drivers/watchdog/lantiq_wdt.c: drop iounmap for devm_ allocated data
watchdog: documentation: describe nowayout in coversion-guide
watchdog: documentation: update index file
watchdog: Convert wm831x driver to devm_kzalloc()
watchdog: add nowayout helpers to Watchdog Timer Driver Kernel API
watchdog: convert drivers/watchdog/* to use module_platform_driver()
watchdog: Use DEFINE_SPINLOCK() for static spinlocks
watchdog: Convert Wolfson drivers to module_platform_driver
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (40 commits)
regulator: set constraints.apply_uV to 0 in of_get_fixed_voltage_config
regulator: max8925: fix enabled/disabled judgement mistake
regulator: add regulator_bulk_force_disable function
regulator: pass regulator_register of_node in fixed voltage driver
regulator: add regulator_force_disable() definition for !CONFIG_REGULATOR
regulator: Enable supply regulator if child rail is enabled.
regulator: mc13892: Convert to devm_kzalloc()
regulator: mc13783: Convert to devm_kzalloc()
regulator: Fix checking return value of create_regulator
regulator: Fix the error handling if create_regulator fails
regulator: Export regulator_is_supported_voltage()
regulator: mc13892: add device tree probe support
regulator: mc13892: remove the unnecessary prefix from regulator name
regulator: Convert wm831x regulator drivers to devm_kzalloc()
regulator: da9052: Staticize non-exported symbols
regulator: Replace kzalloc with devm_kzalloc and if-else with a switch-case for da9052-regulator
regulator: Update da9052-regulator for DT changes
regulator: DA9052/53 Regulator support
regulator: pass device_node to of_get_regulator_init_data()
regulator: If a single voltage is set with device tree then set apply_uV
...
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (31 commits)
pinctrl: remove unnecessary max pin number
pinctrl: correct a offset while enumerating pins
pinctrl: some typo fixes
pinctrl: rename U300 and SIRF pin controllers
pinctrl: pass name instead of device to pin_config_*
pinctrl: add "struct seq_file;" to pinconf.h
pinctrl: conjure names for unnamed pins
pinctrl: add a group-specific hog macro
pinctrl: don't create a device for each pin controller
arm/u300: don't use PINMUX_MAP_PRIMARY*
pinctrl: implement PINMUX_MAP_SYS_HOG
pinctrl: add a pin config interface
pinctrl/coh901: driver to request its pins
pinctrl: u300-pinmux: register proper GPIO ranges
pinctrl: move the U300 GPIO driver to pinctrl
ARM: u300: localize GPIO assignments
pinctrl: make it possible to add multiple maps
pinctrl: make a copy of pinmux map
pinctrl: GPIO direction support for muxing
pinctrl: print pin range in GPIO range debugs
...
* 'upstream-linus' of git://github.com/jgarzik/libata-dev:
ahci: support the STA2X11 I/O Hub
pata_bf54x: fix BMIDE status register emulation
ata: add ata port hibernate callbacks
ata: update ata port's runtime status during system resume
[SCSI] runtime resume parent for child's system-resume
ahci: platform support for suspend/resume
libata-core: kill duplicate statement in ata_do_set_mode()
pata_of_platform: remove direct dependency on OF_IRQ
SATA/PATA: convert drivers/ata/* to use module_platform_driver()
pata_cs5536: forward port changes from cs5536
libata-sff: use ATAPI_{COD|IO}
ata: add ata port runtime PM callbacks
ata: add ata port system PM callbacks
[SCSI] sd: check runtime PM status in sd_shutdown
[SCSI] check runtime PM status in system PM
[SCSI] add flag to skip the runtime PM calls on the host
ata: make ata port as parent device of scsi host
ahci: start engine only during soft/hard resets
Two (or more) concurrent calls of shrink_dcache_parent() on the same dentry may
cause shrink_dcache_parent() to loop forever.
Here's what appears to happen:
1 - CPU0: select_parent(P) finds C and puts it on dispose list, returns 1
2 - CPU1: select_parent(P) locks P->d_lock
3 - CPU0: shrink_dentry_list() locks C->d_lock
dentry_kill(C) tries to lock P->d_lock but fails, unlocks C->d_lock
4 - CPU1: select_parent(P) locks C->d_lock,
moves C from dispose list being processed on CPU0 to the new
dispose list, returns 1
5 - CPU0: shrink_dentry_list() finds dispose list empty, returns
6 - Goto 2 with CPU0 and CPU1 switched
Basically select_parent() steals the dentry from shrink_dentry_list() and thinks
it found a new one, causing shrink_dentry_list() to think it's making progress
and loop over and over.
One way to trigger this is to make udev calls stat() on the sysfs file while it
is going away.
Having a file in /lib/udev/rules.d/ with only this one rule seems to the trick:
ATTR{vendor}=="0x8086", ATTR{device}=="0x10ca", ENV{PCI_SLOT_NAME}="%k", ENV{MATCHADDR}="$attr{address}", RUN+="/bin/true"
Then execute the following loop:
while true; do
echo -bond0 > /sys/class/net/bonding_masters
echo +bond0 > /sys/class/net/bonding_masters
echo -bond1 > /sys/class/net/bonding_masters
echo +bond1 > /sys/class/net/bonding_masters
done
One fix would be to check all callers and prevent concurrent calls to
shrink_dcache_parent(). But I think a better solution is to stop the
stealing behavior.
This patch adds a new dentry flag that is set when the dentry is added to the
dispose list. The flag is cleared in dentry_lru_del() in case the dentry gets a
new reference just before being pruned.
If the dentry has this flag, select_parent() will skip it and let
shrink_dentry_list() retry pruning it. With select_parent() skipping those
dentries there will not be the appearance of progress (new dentries found) when
there is none, hence shrink_dcache_parent() will not loop forever.
Set the flag is also set in prune_dcache_sb() for consistency as suggested by
Linus.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'kvm-updates/3.3' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (74 commits)
KVM: PPC: Whitespace fix for kvm.h
KVM: Fix whitespace in kvm_para.h
KVM: PPC: annotate kvm_rma_init as __init
KVM: x86 emulator: implement RDPMC (0F 33)
KVM: x86 emulator: fix RDPMC privilege check
KVM: Expose the architectural performance monitoring CPUID leaf
KVM: VMX: Intercept RDPMC
KVM: SVM: Intercept RDPMC
KVM: Add generic RDPMC support
KVM: Expose a version 2 architectural PMU to a guests
KVM: Expose kvm_lapic_local_deliver()
KVM: x86 emulator: Use opcode::execute for Group 9 instruction
KVM: x86 emulator: Use opcode::execute for Group 4/5 instructions
KVM: x86 emulator: Use opcode::execute for Group 1A instruction
KVM: ensure that debugfs entries have been created
KVM: drop bsp_vcpu pointer from kvm struct
KVM: x86: Consolidate PIT legacy test
KVM: x86: Do not rely on implicit inclusions
KVM: Make KVM_INTEL depend on CPU_SUP_INTEL
KVM: Use memdup_user instead of kmalloc/copy_from_user
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
vfs: new helper - d_make_root()
dcache: use a dispose list in select_parent
ceph: d_alloc_root() may fail
ext4: fix failure exits
isofs: inode leak on mount failure
Eric Paris