The __latent_entropy gcc attribute can be used only on functions and
variables. If it is on a function then the plugin will instrument it for
gathering control-flow entropy. If the attribute is on a variable then
the plugin will initialize it with random contents. The variable must
be an integer, an integer array type or a structure with integer fields.
These specific functions have been selected because they are init
functions (to help gather boot-time entropy), are called at unpredictable
times, or they have variable loops, each of which provide some level of
latent entropy.
Signed-off-by: Emese Revfy <re.emese@gmail.com>
[kees: expanded commit message]
Signed-off-by: Kees Cook <keescook@chromium.org>
This adds a new gcc plugin named "latent_entropy". It is designed to
extract as much possible uncertainty from a running system at boot time as
possible, hoping to capitalize on any possible variation in CPU operation
(due to runtime data differences, hardware differences, SMP ordering,
thermal timing variation, cache behavior, etc).
At the very least, this plugin is a much more comprehensive example for
how to manipulate kernel code using the gcc plugin internals.
The need for very-early boot entropy tends to be very architecture or
system design specific, so this plugin is more suited for those sorts
of special cases. The existing kernel RNG already attempts to extract
entropy from reliable runtime variation, but this plugin takes the idea to
a logical extreme by permuting a global variable based on any variation
in code execution (e.g. a different value (and permutation function)
is used to permute the global based on loop count, case statement,
if/then/else branching, etc).
To do this, the plugin starts by inserting a local variable in every
marked function. The plugin then adds logic so that the value of this
variable is modified by randomly chosen operations (add, xor and rol) and
random values (gcc generates separate static values for each location at
compile time and also injects the stack pointer at runtime). The resulting
value depends on the control flow path (e.g., loops and branches taken).
Before the function returns, the plugin mixes this local variable into
the latent_entropy global variable. The value of this global variable
is added to the kernel entropy pool in do_one_initcall() and _do_fork(),
though it does not credit any bytes of entropy to the pool; the contents
of the global are just used to mix the pool.
Additionally, the plugin can pre-initialize arrays with build-time
random contents, so that two different kernel builds running on identical
hardware will not have the same starting values.
Signed-off-by: Emese Revfy <re.emese@gmail.com>
[kees: expanded commit message and code comments]
Signed-off-by: Kees Cook <keescook@chromium.org>
Pull ARM fixes from Russell King:
"Three relatively small fixes for ARM:
- Roger noticed that dma_max_pfn() was calculating the upper limit
wrongly, by adding the PFN offset of memory twice.
- A fix from Robin to correct parsing of MPIDR values when the
address size is larger than one BE32 unit.
- A fix from Srinivas to ensure that we do not rely on the boot
loader (or previous Linux kernel) setting the translation table
base register a certain way in the decompressor, which can lead to
crashes"
* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
ARM: 8618/1: decompressor: reset ttbcr fields to use TTBR0 on ARMv7
ARM: 8617/1: dma: fix dma_max_pfn()
ARM: 8616/1: dt: Respect property size when parsing CPUs
If the bootloader uses the long descriptor format and jumps to
kernel decompressor code, TTBCR may not be in a right state.
Before enabling the MMU, it is required to clear the TTBCR.PD0
field to use TTBR0 for translation table walks.
The commit dbece45894 ("ARM: 7501/1: decompressor:
reset ttbcr for VMSA ARMv7 cores") does the reset of TTBCR.N, but
doesn't consider all the bits for the size of TTBCR.N.
Clear TTBCR.PD0 field and reset all the three bits of TTBCR.N to
indicate the use of TTBR0 and the correct base address width.
Fixes: dbece45894 ("ARM: 7501/1: decompressor: reset ttbcr for VMSA ARMv7 cores")
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Srinivas Ramana <sramana@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull x86 fixes from Thomas Gleixner:
"The last regression fixes for 4.8 final:
- Two patches addressing the fallout of the CR4 optimizations which
caused CR4-less machines to fail.
- Fix the VDSO build on big endian machines
- Take care of FPU initialization if no CPUID is available otherwise
task struct size ends up being zero
- Fix up context tracking in case load_gs_index fails"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/entry/64: Fix context tracking state warning when load_gs_index fails
x86/boot: Initialize FPU and X86_FEATURE_ALWAYS even if we don't have CPUID
x86/vdso: Fix building on big endian host
x86/boot: Fix another __read_cr4() case on 486
x86/init: Fix cr4_init_shadow() on CR4-less machines
Pull sparc fixes from David Miller:
1) Fix section mismatches in some builds, from Paul Gortmaker.
2) Need to count huge zero page mappings when doing TSB sizing, from
Mike Kravetz.
3) Fix handing of cpu_possible_mask when nr_cpus module option is
specified, from Atish Patra.
4) Don't allocate irq stacks until nr_irqs has been processed, also
from Atish Patra.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
sparc64: Fix non-SMP build.
sparc64: Fix irq stack bootmem allocation.
sparc64: Fix cpu_possible_mask if nr_cpus is set
sparc64 mm: Fix more TSB sizing issues
sparc64: fix section mismatch in find_numa_latencies_for_group
Pull networking fixes from David Miller:
1) Fix wrong TCP checksums on MTU probing when checksum offloading is
disabled, from Douglas Caetano dos Santos.
2) Fix qdisc backlog updates in qfq and sfb schedulers, from Cong Wang.
3) Route lookup flow key protocol value is wrong in ip6gre_xmit_other(),
fix from Lance Richardson.
4) Scheduling while atomic in multicast routing code of ipv4 and ipv6,
fix from Nikolay Aleksandrov.
5) Fix packet alignment in fec driver, from Eric Nelson.
6) Fix perf regression in sctp due to struct layout and cache misses,
from Xin Long.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
sctp: fix the issue sctp_diag uses lock_sock in rcu_read_lock
sctp: change to check peer prsctp_capable when using prsctp polices
sctp: remove prsctp_param from sctp_chunk
sctp: move sent_count to the memory hole in sctp_chunk
tg3: Avoid NULL pointer dereference in tg3_io_error_detected()
act_ife: Fix false encoding
act_ife: Fix external mac header on encode
VSOCK: Don't dec ack backlog twice for rejected connections
Revert "net: ethernet: bcmgenet: use phydev from struct net_device"
net: fec: align IP header in hardware
net: fec: remove QUIRK_HAS_RACC from i.mx27
net: fec: remove QUIRK_HAS_RACC from i.mx25
ipmr, ip6mr: fix scheduling while atomic and a deadlock with ipmr_get_route
ip6_gre: fix flowi6_proto value in ip6gre_xmit_other()
tcp: fix a compile error in DBGUNDO()
tcp: fix wrong checksum calculation on MTU probing
sch_sfb: keep backlog updated with qlen
sch_qfq: keep backlog updated with qlen
can: dev: fix deadlock reported after bus-off
When discovering the number of VPEs per core, smp_num_siblings will be
incorrect for kernels built without support for the MIPS MultiThreading
(MT) ASE running on systems which implement said ASE. This leads to
accesses to VPEs in secondary cores being performed incorrectly since
mips_cm_vp_id calculates the wrong ID to write to the local "other"
registers. Fix this by examining the number of VPEs in the core as
reported by the CM.
This patch presumes that the number of VPEs will be the same in each
core of the system. As this path only applies to systems with CM version
2.5 or lower, and this property is true of all such known systems, this
is likely to be fine but is described in a comment for good measure.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14338/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
One final fix before 4.8: there's a memory leak triggered by turning scsi mq
off due to the fact that we assume on host release that the already running
hosts weren't mq based because that's the state of the global flag (even
though they were), so fix it by tracking this on a per host host basis.
Signed-off-by: James Bottomley <jejb@linux.vnet.ibm.com>
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fix from James Bottomley:
"One final fix before 4.8.
There was a memory leak triggered by turning scsi mq off due to the
fact that we assume on host release that the already running hosts
weren't mq based because that's the state of the global flag (even
though they were).
Fix it by tracking this on a per host host basis"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: Avoid that toggling use_blk_mq triggers a memory leak
Pull input fix from Dmitry Torokhov:
"One small change to make joydev (which is used by older games) to bind
to devices that export Z axis but not X or Y (such as TRC rudder)"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: joydev - recognize devices with Z axis as joysticks
Merge more fixes from Andrew Morton:
"Three fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
include/linux/property.h: fix typo/compile error
ocfs2: fix deadlock on mmapped page in ocfs2_write_begin_nolock()
mm: workingset: fix crash in shadow node shrinker caused by replace_page_cache_page()
This fixes commit d76eebfa17 ("include/linux/property.h: fix build
issues with gcc-4.4.4").
With that commit we get the following compile error when using the
PROPERTY_ENTRY_INTEGER_ARRAY macro.
include/linux/property.h:201:39: error: `u32_data' undeclared (first
use in this function)
PROPERTY_ENTRY_INTEGER_ARRAY(_name_, u32, _val_)
^
include/linux/property.h:193:17: note: in definition of macro
`PROPERTY_ENTRY_INTEGER_ARRAY'
{ .pointer = { _type_##_data = _val_ } }, \
^
This needs a '.' to reference the union member. It seems this was just
overlooked here since it is done correctly in similar constructs in
other parts of the original commit.
This fix is in preparation of upcoming commits that will use this macro.
Fixes: commit d76eebfa17 ("include/linux/property.h: fix build issues with gcc-4.4.4")
Link: http://lkml.kernel.org/r/2de3b929290d88a723ed829a3e3cbd02044714df.1475114627.git.johnyoun@synopsys.com
Signed-off-by: John Youn <johnyoun@synopsys.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The testcase "mmaptruncate" of ocfs2-test deadlocks occasionally.
In this testcase, we create a 2*CLUSTER_SIZE file and mmap() on it;
there are 2 process repeatedly performing the following operations
respectively: one is doing memset(mmaped_addr + 2*CLUSTER_SIZE - 1, 'a',
1), while the another is playing ftruncate(fd, 2*CLUSTER_SIZE) and then
ftruncate(fd, CLUSTER_SIZE) again and again.
This is the backtrace when the deadlock happens:
__wait_on_bit_lock+0x50/0xa0
__lock_page+0xb7/0xc0
ocfs2_write_begin_nolock+0x163f/0x1790 [ocfs2]
ocfs2_page_mkwrite+0x1c7/0x2a0 [ocfs2]
do_page_mkwrite+0x66/0xc0
handle_mm_fault+0x685/0x1350
__do_page_fault+0x1d8/0x4d0
trace_do_page_fault+0x37/0xf0
do_async_page_fault+0x19/0x70
async_page_fault+0x28/0x30
In ocfs2_write_begin_nolock(), we first grab the pages and then allocate
disk space for this write; ocfs2_try_to_free_truncate_log() will be
called if -ENOSPC is returned; if we're lucky to get enough clusters,
which is usually the case, we start over again.
But in ocfs2_free_write_ctxt() the target page isn't unlocked, so we
will deadlock when trying to grab the target page again.
Also, -ENOMEM might be returned in ocfs2_grab_pages_for_write().
Another deadlock will happen in __do_page_mkwrite() if
ocfs2_page_mkwrite() returns non-VM_FAULT_LOCKED, and along with a
locked target page.
These two errors fail on the same path, so fix them by unlocking the
target page manually before ocfs2_free_write_ctxt().
Jan Kara helps me clear out the JBD2 part, and suggest the hint for root
cause.
Changes since v1:
1. Also put ENOMEM error case into consideration.
Link: http://lkml.kernel.org/r/1474173902-32075-1-git-send-email-zren@suse.com
Signed-off-by: Eric Ren <zren@suse.com>
Reviewed-by: He Gang <ghe@suse.com>
Acked-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Antonio reports the following crash when using fuse under memory pressure:
kernel BUG at /build/linux-a2WvEb/linux-4.4.0/mm/workingset.c:346!
invalid opcode: 0000 [#1] SMP
Modules linked in: all of them
CPU: 2 PID: 63 Comm: kswapd0 Not tainted 4.4.0-36-generic #55-Ubuntu
Hardware name: System manufacturer System Product Name/P8H67-M PRO, BIOS 3904 04/27/2013
task: ffff88040cae6040 ti: ffff880407488000 task.ti: ffff880407488000
RIP: shadow_lru_isolate+0x181/0x190
Call Trace:
__list_lru_walk_one.isra.3+0x8f/0x130
list_lru_walk_one+0x23/0x30
scan_shadow_nodes+0x34/0x50
shrink_slab.part.40+0x1ed/0x3d0
shrink_zone+0x2ca/0x2e0
kswapd+0x51e/0x990
kthread+0xd8/0xf0
ret_from_fork+0x3f/0x70
which corresponds to the following sanity check in the shadow node
tracking:
BUG_ON(node->count & RADIX_TREE_COUNT_MASK);
The workingset code tracks radix tree nodes that exclusively contain
shadow entries of evicted pages in them, and this (somewhat obscure)
line checks whether there are real pages left that would interfere with
reclaim of the radix tree node under memory pressure.
While discussing ways how fuse might sneak pages into the radix tree
past the workingset code, Miklos pointed to replace_page_cache_page(),
and indeed there is a problem there: it properly accounts for the old
page being removed - __delete_from_page_cache() does that - but then
does a raw raw radix_tree_insert(), not accounting for the replacement
page. Eventually the page count bits in node->count underflow while
leaving the node incorrectly linked to the shadow node LRU.
To address this, make sure replace_page_cache_page() uses the tracked
page insertion code, page_cache_tree_insert(). This fixes the page
accounting and makes sure page-containing nodes are properly unlinked
from the shadow node LRU again.
Also, make the sanity checks a bit less obscure by using the helpers for
checking the number of pages and shadows in a radix tree node.
Fixes: 449dd6984d ("mm: keep page cache radix tree nodes in check")
Link: http://lkml.kernel.org/r/20160919155822.29498-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Antonio SJ Musumeci <trapexit@spawn.link>
Debugged-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <stable@vger.kernel.org> [3.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change my email address to my kernel.org account instead of the ARM one.
Signed-off-by: Javi Merino <javi.merino@arm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This warning:
WARNING: CPU: 0 PID: 3331 at arch/x86/entry/common.c:45 enter_from_user_mode+0x32/0x50
CPU: 0 PID: 3331 Comm: ldt_gdt_64 Not tainted 4.8.0-rc7+ #13
Call Trace:
dump_stack+0x99/0xd0
__warn+0xd1/0xf0
warn_slowpath_null+0x1d/0x20
enter_from_user_mode+0x32/0x50
error_entry+0x6d/0xc0
? general_protection+0x12/0x30
? native_load_gs_index+0xd/0x20
? do_set_thread_area+0x19c/0x1f0
SyS_set_thread_area+0x24/0x30
do_int80_syscall_32+0x7c/0x220
entry_INT80_compat+0x38/0x50
... can be reproduced by running the GS testcase of the ldt_gdt test unit in
the x86 selftests.
do_int80_syscall_32() will call enter_form_user_mode() to convert context
tracking state from user state to kernel state. The load_gs_index() call
can fail with user gsbase, gsbase will be fixed up and proceed if this
happen.
However, enter_from_user_mode() will be called again in the fixed up path
though it is context tracking kernel state currently.
This patch fixes it by just fixing up gsbase and telling lockdep that IRQs
are off once load_gs_index() failed with user gsbase.
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1475197266-3440-1-git-send-email-wanpeng.li@hotmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Otherwise arch_task_struct_size == 0 and we die. While we're at it,
set X86_FEATURE_ALWAYS, too.
Reported-by: David Saggiorato <david@saggiorato.net>
Tested-by: David Saggiorato <david@saggiorato.net>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fixes: aaeb5c01c5b ("x86/fpu, sched: Introduce CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT and use it on x86")
Link: http://lkml.kernel.org/r/8de723afbf0811071185039f9088733188b606c9.1475103911.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We need to call GET_LE to read hdr->e_type.
Fixes: 57f90c3dfc ("x86/vdso: Error out if the vDSO isn't a valid DSO")
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: linux-next@vger.kernel.org
Link: http://lkml.kernel.org/r/20160929193442.GA16617@gate.crashing.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The condition for reading CR4 was wrong: there are some CPUs with
CPUID but not CR4. Rather than trying to make the condition exact,
use __read_cr4_safe().
Fixes: 18bc7bd523 ("x86/boot: Synchronize trampoline_cr4_features and mmu_cr4_features directly")
Reported-by: david@saggiorato.net
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Link: http://lkml.kernel.org/r/8c453a61c4f44ab6ff43c29780ba04835234d2e5.1475178369.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
When sctp dumps all the ep->assocs, it needs to lock_sock first,
but now it locks sock in rcu_read_lock, and lock_sock may sleep,
which would break rcu_read_lock.
This patch is to get and hold one sock when traversing the list.
After that and get out of rcu_read_lock, lock and dump it. Then
it will traverse the list again to get the next one until all
sctp socks are dumped.
For sctp_diag_dump_one, it fixes this issue by holding asoc and
moving cb() out of rcu_read_lock in sctp_transport_lookup_process.
Fixes: 8f840e47f1 ("sctp: add the sctp_diag.c file")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Xin Long says:
====================
sctp: a bunch of fixes for prsctp polices
This patchset is to fix 2 issues for prsctp polices:
1. patch 1 and 2 fix "netperf-Throughput_Mbps -37.2% regression" issue
when overloading the CPU.
2. patch 3 fix "prsctp polices should check both sides' prsctp_capable,
instead of only local side".
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Now before using prsctp polices, sctp uses asoc->prsctp_enable to
check if prsctp is enabled. However asoc->prsctp_enable is set only
means local host support prsctp, sctp should not abandon packet if
peer host doesn't enable prsctp.
So this patch is to use asoc->peer.prsctp_capable to check if prsctp
is enabled on both side, instead of asoc->prsctp_enable, as asoc's
peer.prsctp_capable is set only when local and peer both enable prsctp.
Fixes: a6c2f79287 ("sctp: implement prsctp TTL policy")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now sctp uses chunk->prsctp_param to save the prsctp param for all the
prsctp polices, we didn't need to introduce prsctp_param to sctp_chunk.
We can just use chunk->sinfo.sinfo_timetolive for RTX and BUF polices,
and reuse msg->expires_at for TTL policy, as the prsctp polices and old
expires policy are mutual exclusive.
This patch is to remove prsctp_param from sctp_chunk, and reuse msg's
expires_at for TTL and chunk's sinfo.sinfo_timetolive for RTX and BUF
polices.
Note that sctp can't use chunk's sinfo.sinfo_timetolive for TTL policy,
as it needs a u64 variables to save the expires_at time.
This one also fixes the "netperf-Throughput_Mbps -37.2% regression"
issue.
Fixes: a6c2f79287 ("sctp: implement prsctp TTL policy")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now pahole sctp_chunk, it has 2 memory holes:
struct sctp_chunk {
struct list_head list;
atomic_t refcnt;
/* XXX 4 bytes hole, try to pack */
...
long unsigned int prsctp_param;
int sent_count;
/* XXX 4 bytes hole, try to pack */
This patch is to move up sent_count to fill the 1st one and eliminate
the 2nd one.
It's not just another struct compaction, it also fixes the "netperf-
Throughput_Mbps -37.2% regression" issue when overloading the CPU.
Fixes: a6c2f79287 ("sctp: implement prsctp TTL policy")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While the driver is probing the adapter, an error may occur before the
netdev structure is allocated and attached to pci_dev. In this case,
not only netdev isn't available, but the tg3 private structure is also
not available as it is just math from the NULL pointer, so dereferences
must be skipped.
The following trace is seen when the error is triggered:
[1.402247] Unable to handle kernel paging request for data at address 0x00001a99
[1.402410] Faulting instruction address: 0xc0000000007e33f8
[1.402450] Oops: Kernel access of bad area, sig: 11 [#1]
[1.402481] SMP NR_CPUS=2048 NUMA PowerNV
[1.402513] Modules linked in:
[1.402545] CPU: 0 PID: 651 Comm: eehd Not tainted 4.4.0-36-generic #55-Ubuntu
[1.402591] task: c000001fe4e42a20 ti: c000001fe4e88000 task.ti: c000001fe4e88000
[1.402742] NIP: c0000000007e33f8 LR: c0000000007e3164 CTR: c000000000595ea0
[1.402787] REGS: c000001fe4e8b790 TRAP: 0300 Not tainted (4.4.0-36-generic)
[1.402832] MSR: 9000000100009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 28000422 XER: 20000000
[1.403058] CFAR: c000000000008468 DAR: 0000000000001a99 DSISR: 42000000 SOFTE: 1
GPR00: c0000000007e3164 c000001fe4e8ba10 c0000000015c5e00 0000000000000000
GPR04: 0000000000000001 0000000000000000 0000000000000039 0000000000000299
GPR08: 0000000000000000 0000000000000001 c000001fe4e88000 0000000000000006
GPR12: 0000000000000000 c00000000fb40000 c0000000000e6558 c000003ca1bffd00
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
GPR20: 0000000000000000 0000000000000000 0000000000000000 c000000000d52768
GPR24: c000000000d52740 0000000000000100 c000003ca1b52000 0000000000000002
GPR28: 0000000000000900 0000000000000000 c00000000152a0c0 c000003ca1b52000
[1.404226] NIP [c0000000007e33f8] tg3_io_error_detected+0x308/0x340
[1.404265] LR [c0000000007e3164] tg3_io_error_detected+0x74/0x340
This patch avoids the NULL pointer dereference by moving the access after
the netdev NULL pointer check on tg3_io_error_detected(). Also, we add a
check for netdev being NULL on tg3_io_resume() [suggested by Michael Chan].
Fixes: 0486a063b1 ("tg3: prevent ifup/ifdown during PCI error recovery")
Fixes: dfc8f37031 ("net/tg3: Release IRQs on permanent error")
Tested-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Signed-off-by: Milton Miller <miltonm@us.ibm.com>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Acked-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Merge tag 'drm-fixes-for-v4.8-final' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"drm fixes for final 4.8.
One big regression fix for udl, along with two amdgpu fixes and two
nouveau fixes.
All seems pretty safe and useful"
* tag 'drm-fixes-for-v4.8-final' of git://people.freedesktop.org/~airlied/linux:
drm/udl: fix line iterator in damage handling
drm/radeon/si/dpm: add workaround for for Jet parts
drm/amdgpu: disable CRTCs before teardown
drm/nouveau: Revert "bus: remove cpu_coherent flag"
drm/nouveau/fifo/nv04: avoid ramht race against cookie insertion
Pull libnvdimm fixes from Dan Williams:
- Four fixes for "flush hint" support.
Flush hints are addresses advertised by the ACPI 6+ NFIT (NVDIMM
Firmware Interface Table) that when written and fenced guarantee that
writes pending in platform write buffers (outside the cpu) have been
flushed to media. They might also be used by hypervisors as a
trigger condition to flush guest-persistent memory ranges to storage.
Fix a potential data corruption issue, a broken definition of the
hint array, a wrong allocation size for the unit test implementation
of the flush hint table, and missing NULL check in an error path.
The unit test, while it did not prevent these bugs from being
merged, at least triggered occasional crashes in advance of
production usages.
- Fix handling of ACPI DSM error status results. The DSM mechanism
allows communication with platform and memory device firmware. We
correctly parse known errors, but were silently ignoring others.
Fix it to consistently fail any command with a non-zero status return
that we otherwise do not interpret / handle.
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
libnvdimm, region: fix flush hint table thinko
nfit: fail DSMs that return non-zero status by default
libnvdimm: fix devm_nvdimm_memremap() error path
tools/testing/nvdimm: fix allocation range for mock flush hint tables
nvdimm: fix PHYS_PFN/PFN_PHYS mixup
The paging_init() function contains code which detects that highmem is
in use but unsupported due to dcache aliasing. However this code was
ineffective because it was being run before the caches are probed,
meaning that cpu_has_dc_aliases would always evaluate to false (unless a
platform overrides it to a compile-time constant) and the detection of
the unsupported case is never triggered. The kernel would then go on to
attempt to use highmem & either hit coherency issues or trigger the
BUG_ON in flush_kernel_dcache_page().
Fix this by running paging_init() later than cpu_cache_init(), such that
the cpu_has_dc_aliases macro will evaluate correctly & the unsupported
highmem case will be detected successfully.
This then leads to a formerly hidden issue in that
mem_init_free_highmem() will attempt to free all highmem pages, even
though we're avoiding use of them & don't have valid page structs for
them. This leads to an invalid pointer dereference & a TLB exception.
Avoid this by skipping the loop in mem_init_free_highmem() if
cpu_has_dc_aliases evaluates true.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: Rabin Vincent <rabinv@axis.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Alexander Sverdlin <alexander.sverdlin@gmail.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Jaedon Shin <jaedon.shin@gmail.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Cc: Jonas Gorski <jogo@openwrt.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14184/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Malta boards used with CPU emulators feature a switch to disable use of
an IOCU. Software has to check this switch & ignore any present IOCU if
the switch is closed. The read used to do this was unsafe for 64 bit
kernels, as it simply casted the address 0xbf403000 to a pointer &
dereferenced it. Whilst in a 32 bit kernel this would access kseg1, in a
64 bit kernel this attempts to access xuseg & results in an address
error exception.
Fix by accessing a correctly formed ckseg1 address generated using the
CKSEG1ADDR macro.
Whilst modifying this code, define the name of the register and the bit
we care about within it, which indicates whether PCI DMA is routed to
the IOCU or straight to DRAM. The code previously checked that bit 0 was
also set, but the least significant 7 bits of the CONFIG_GEN0 register
contain the value of the MReqInfo signal provided to the IOCU OCP bus,
so singling out bit 0 makes little sense & that part of the check is
dropped.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: b6d92b4a6b ("MIPS: Add option to disable software I/O coherency.")
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14187/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When the kernel is built for microMIPS, branches targets need to be
known to be microMIPS code in order to result in bit 0 of the PC being
set. The branch target in the BUILD_ROLLBACK_PROLOGUE macro was simply
the end of the macro, which may be pointing at padding rather than at
code. This results in recent enough GNU linkers complaining like so:
mips-img-linux-gnu-ld: arch/mips/built-in.o: .text+0x3e3c: Unsupported branch between ISA modes.
mips-img-linux-gnu-ld: final link failed: Bad value
Makefile:936: recipe for target 'vmlinux' failed
make: *** [vmlinux] Error 1
Fix this by changing the branch target to be the start of the
appropriate handler, skipping over any padding.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14019/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
On current P-series cores from Imagination the FTLB can be enabled or
disabled via a bit in the Config6 register, and an execution hazard is
created by changing the value of bit. The ftlb_disable function already
cleared that hazard but that does no good for other callers. Clear the
hazard in the set_ftlb_enable function that creates it, and only for the
cores where it applies.
This has the effect of reverting c982c6d6c4 ("MIPS: cpu-probe: Remove
cp0 hazard barrier when enabling the FTLB") which was incorrect.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: c982c6d6c4 ("MIPS: cpu-probe: Remove cp0 hazard barrier when enabling the FTLB")
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14023/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
On some cores (proAptiv, P5600) we make use of the sizes of the TLBs
to determine the desired FTLB:VTLB write ratio. However set_ftlb_enable
& thus calculate_ftlb_probability is called before decode_config4. This
results in us calculating a probability based on zero sizes, and we end
up setting FTLBP=3 for a 3:1 FTLB:VTLB write ratio in all cases. This
will make abysmal use of the available FTLB resources in the affected
cores.
Fix this by configuring the FTLB probability after having decoded
config4. However we do need to have enabled the FTLB before that point
such that fields in config4 actually reflect that an FTLB is present. So
set_ftlb_enable is now called twice, with flags indicating that it
should configure the write probability only the second time.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: cf0a8aa022 ("MIPS: cpu-probe: Set the FTLB probability bit on supported cores")
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14022/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The FTLBP field in Config7 for the I6400 is intended as chicken bits for
debugging rather than as a field that software actually makes use of.
For best performance, FTLBP should be left at its default value of 0
with all TLB writes hitting the FTLB by default.
Additionally, since set_ftlb_enable is called from decode_configs before
decode_config4 which determines the size of the TLBs, this was
previously always setting FTLBP=3 for a 3:1 FTLB:VTLB write ratio which
makes abysmal use of the available FTLB resources.
This effectively reverts b0c4e1b79d8a ("MIPS: Set up FTLB probability
for I6400").
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Fixes: b0c4e1b79d8a ("MIPS: Set up FTLB probability for I6400")
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14021/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When expanding the la or dla pseudo-instruction in a delay slot the GNU
assembler will complain should the pseudo-instruction expand to multiple
actual instructions, since only the first of them will be in the delay
slot leading to the pseudo-instruction being only partially executed if
the branch is taken. Use of PTR_LA in the dec int-handler.S leads to
such warnings:
arch/mips/dec/int-handler.S: Assembler messages:
arch/mips/dec/int-handler.S:149: Warning: macro instruction expanded into multiple instructions in a branch delay slot
arch/mips/dec/int-handler.S:198: Warning: macro instruction expanded into multiple instructions in a branch delay slot
Avoid this by open coding the PTR_LA macros.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We clear the OF_POPULATED flag for the GPIO controller node on Octeon
processors. Otherwise, none of the devices hanging on the GPIO lines
are probed. The 'gpio-leds' driver on OCTEON failed to probe in addition
to other devices on Cavium 71xx and 78xx development boards.
Fixes: 15cc2ed6dc ("of/irq: Mark initialised interrupt controllers as populated")
Signed-off-by: Steven J. Hill <steven.hill@cavium.com>
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: David Daney <david.daney@cavium.com>
Cc: Rob Herring <robh@kernel.org>
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14091/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch_uprobe_pre_xol needs to emulate a branch if a branch instruction
has been replaced with a breakpoint, but in fact an uninitialised local
variable was passed to the emulator routine instead of the original
instruction
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Fixes: 40e084a506 ('MIPS: Add uprobes support.')
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14300/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Generic kernel code implements a weak version of set_orig_insn that
moves cached 'insn' from arch_uprobe to the original code location when
the trap is removed.
MIPS variant used arch_uprobe->orig_inst which was never initialised
properly, so this code only inserted a nop instead of the original
instruction. With that change orig_inst can also be safely removed.
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Fixes: 40e084a506 ('MIPS: Add uprobes support.')
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14299/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
arch_uretprobe_hijack_return_addr should replace the return address for
a call with a trampoline address.
Signed-off-by: Marcin Nowakowski <marcin.nowakowski@imgtec.com>
Fixes: 40e084a506 ('MIPS: Add uprobes support.')
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14298/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 0d2808f338 ("MIPS: smp-cps: Add support for CPU hotplug of
MIPSr6 processors") added a call to mips_cm_lock_other in order to lock
the CPC in CPUs containing a version 3 or higher Coherence Manager,
which use the general CM core other register, where previous CMs had a
dedicated core other register for the CPC.
A kernel BUG() is triggered, however, if mips_cm_lock_other is called
with a VP other than 0 on a CPU with CM < 3, a condition introduced by
0d2808f338.
Avoid the BUG() by always locking VP0 when locking the CPC, since the
required register, cpc_stat_conf, is shared by all vps in a core.
Fixes: 0d2808f338 ("MIPS: smp-cps: Add support for CPU hotplug...)
Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Qais Yousef <qsyousef@gmail.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14297/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Since commit 6ce0d20016 ("ARM: dma: Use dma_pfn_offset for dma address translation"),
dma_to_pfn() already returns the PFN with the physical memory start offset
so we don't need to add it again.
This fixes USB mass storage lock-up problem on systems that can't do DMA
over the entire physical memory range (e.g.) Keystone 2 systems with 4GB RAM
can only do DMA over the first 2GB. [K2E-EVM].
What happens there is that without this patch SCSI layer sets a wrong
bounce buffer limit in scsi_calculate_bounce_limit() for the USB mass
storage device. dma_max_pfn() evaluates to 0x8fffff and bounce_limit
is set to 0x8fffff000 whereas maximum DMA'ble physical memory on Keystone 2
is 0x87fffffff. This results in non DMA'ble pages being given to the
USB controller and hence the lock-up.
NOTE: in the above case, USB-SCSI-device's dma_pfn_offset was showing as 0.
This should have really been 0x780000 as on K2e, LOWMEM_START is 0x80000000
and HIGHMEM_START is 0x800000000. DMA zone is 2GB so dma_max_pfn should be
0x87ffff. The incorrect dma_pfn_offset for the USB storage device is because
USB devices are not correctly inheriting the dma_pfn_offset from the
USB host controller. This will be fixed by a separate patch.
Fixes: 6ce0d20016 ("ARM: dma: Use dma_pfn_offset for dma address translation")
Cc: stable@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Olof Johansson <olof@lixom.net>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Reported-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Whilst MPIDR values themselves are less than 32 bits, it is still
perfectly valid for a DT to have #address-cells > 1 in the CPUs node,
resulting in the "reg" property having leading zero cell(s). In that
situation, the big-endian nature of the data conspires with the current
behaviour of only reading the first cell to cause the kernel to think
all CPUs have ID 0, and become resoundingly unhappy as a consequence.
Take the full property length into account when parsing CPUs so as to
be correct under any circumstances.
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Need to provide a dummy smp_fill_in_cpu_possible_map.
Fixes: 9b2f753ec2 ("sparc64: Fix cpu_possible_mask if nr_cpus is set")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge fixes from Andrew Morton:
"4 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mem-hotplug: use nodes that contain memory as mask in new_node_page()
scripts/recordmcount.c: account for .softirqentry.text
dma-mapping.h: preserve unmap info for CONFIG_DMA_API_DEBUG
mm,ksm: fix endless looping in allocating memory when ksm enable
9bb627be47 ("mem-hotplug: don't clear the only node in new_node_page()")
prevents allocating from an empty nodemask, but as David points out, it is
still wrong. As node_online_map may include memoryless nodes, only
allocating from these nodes is meaningless.
This patch uses node_states[N_MEMORY] mask to prevent the above case.
Fixes: 9bb627be47 ("mem-hotplug: don't clear the only node in new_node_page()")
Fixes: 394e31d2ce ("mem-hotplug: alloc new page from a nearest neighbor node when mem-offline")
Link: http://lkml.kernel.org/r/1474447117.28370.6.camel@TP420
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Suggested-by: David Rientjes <rientjes@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: John Allen <jallen@linux.vnet.ibm.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
be7635e728 ("arch, ftrace: for KASAN put hard/soft IRQ entries into
separate sections") added .softirqentry.text section, but it was not added
to recordmcount. So functions in the section are untracable. Add the
section to scripts/recordmcount.c and scripts/recordmcount.pl.
Fixes: be7635e728 ("arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections")
Link: http://lkml.kernel.org/r/1474902626-73468-1-git-send-email-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Steve Rostedt <rostedt@goodmis.org>
Cc: <stable@vger.kernel.org> [4.6+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When CONFIG_DMA_API_DEBUG is enabled we need to preserve unmapping address
even if "unmap" is a no-op for our architecutre because we need
debug_dma_unmap_page() to correctly cleanup all of the debug bookkeeping.
Failing to do so results in a false positive warnings about previously
mapped areas never being unmapped.
Link: http://lkml.kernel.org/r/1474387125-3713-1-git-send-email-andrew.smirnov@gmail.com
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Cc: "Luis R. Rodriguez" <mcgrof@suse.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Geliang Tang <geliangtang@163.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I hit the following hung task when runing a OOM LTP test case with 4.1
kernel.
Call trace:
[<ffffffc000086a88>] __switch_to+0x74/0x8c
[<ffffffc000a1bae0>] __schedule+0x23c/0x7bc
[<ffffffc000a1c09c>] schedule+0x3c/0x94
[<ffffffc000a1eb84>] rwsem_down_write_failed+0x214/0x350
[<ffffffc000a1e32c>] down_write+0x64/0x80
[<ffffffc00021f794>] __ksm_exit+0x90/0x19c
[<ffffffc0000be650>] mmput+0x118/0x11c
[<ffffffc0000c3ec4>] do_exit+0x2dc/0xa74
[<ffffffc0000c46f8>] do_group_exit+0x4c/0xe4
[<ffffffc0000d0f34>] get_signal+0x444/0x5e0
[<ffffffc000089fcc>] do_signal+0x1d8/0x450
[<ffffffc00008a35c>] do_notify_resume+0x70/0x78
The oom victim cannot terminate because it needs to take mmap_sem for
write while the lock is held by ksmd for read which loops in the page
allocator
ksm_do_scan
scan_get_next_rmap_item
down_read
get_next_rmap_item
alloc_rmap_item #ksmd will loop permanently.
There is no way forward because the oom victim cannot release any memory
in 4.1 based kernel. Since 4.6 we have the oom reaper which would solve
this problem because it would release the memory asynchronously.
Nevertheless we can relax alloc_rmap_item requirements and use
__GFP_NORETRY because the allocation failure is acceptable as ksm_do_scan
would just retry later after the lock got dropped.
Such a patch would be also easy to backport to older stable kernels which
do not have oom_reaper.
While we are at it add GFP_NOWARN so the admin doesn't have to be alarmed
by the allocation failure.
Link: http://lkml.kernel.org/r/1474165570-44398-1-git-send-email-zhongjiang@huawei.com
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Suggested-by: Hugh Dickins <hughd@google.com>
Suggested-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
