The task structure is freed while get_mem_cgroup_from_mm() holds
rcu_read_lock() and dereferences mm->owner.
get_mem_cgroup_from_mm() failing fork()
---- ---
task = mm->owner
mm->owner = NULL;
free(task)
if (task) *task; /* use after free */
The fix consists in freeing the task with RCU also in the fork failure
case, exactly like it always happens for the regular exit(2) path. That
is enough to make the rcu_read_lock hold in get_mem_cgroup_from_mm()
(left side above) effective to avoid a use after free when dereferencing
the task structure.
An alternate possible fix would be to defer the delivery of the
userfaultfd contexts to the monitor until after fork() is guaranteed to
succeed. Such a change would require more changes because it would
create a strict ordering dependency where the uffd methods would need to
be called beyond the last potentially failing branch in order to be
safe. This solution as opposed only adds the dependency to common code
to set mm->owner to NULL and to free the task struct that was pointed by
mm->owner with RCU, if fork ends up failing. The userfaultfd methods
can still be called anywhere during the fork runtime and the monitor
will keep discarding orphaned "mm" coming from failed forks in userland.
This race condition couldn't trigger if CONFIG_MEMCG was set =n at build
time.
[aarcange@redhat.com: improve changelog, reduce #ifdefs per Michal]
Link: http://lkml.kernel.org/r/20190429035752.4508-1-aarcange@redhat.com
Link: http://lkml.kernel.org/r/20190325225636.11635-2-aarcange@redhat.com
Fixes: 893e26e61d ("userfaultfd: non-cooperative: Add fork() event")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Tested-by: zhong jiang <zhongjiang@huawei.com>
Reported-by: syzbot+cbb52e396df3e565ab02@syzkaller.appspotmail.com
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: zhong jiang <zhongjiang@huawei.com>
Cc: syzbot+cbb52e396df3e565ab02@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the user downloads and applies patch-5.1.gz using patch(1), the x bit
on kernel/gen_ikh_data.sh is not set.
/bin/sh: 1: ./kernel/gen_ikh_data.sh: Permission denied
Fix this by using CONFIG_SHELL.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The test case we have is rightfully failing with the current kernel:
io_uring_setup(1, 0x7ffe2cafebe0), flags: IORING_SETUP_SQPOLL|IORING_SETUP_SQ_AFF, resv: 0x00000000 0x00000000 0x00000000 0x00000000 0x00000000, sq_thread_cpu: 4
expected -1, got 3
This is in a vm, and CPU3 is the last valid one, hence asking for 4
should fail the setup with -EINVAL, not succeed. The problem is that
we're using array_index_nospec() with nr_cpu_ids as the index, hence we
wrap and end up using CPU0 instead of CPU4. This makes the setup
succeed where it should be failing.
We don't need to use array_index_nospec() as we're not indexing any
array with this. Instead just compare with nr_cpu_ids directly. This
is fine as we're checking with cpu_online() afterwards.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The recent commit to cleanup ifdefs in the hugepage initialisation led
to crashes when using 4K pages as reported by Sachin:
BUG: Kernel NULL pointer dereference at 0x0000001c
Faulting instruction address: 0xc000000001d1e58c
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=4K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
...
CPU: 3 PID: 4635 Comm: futex_wake04 Tainted: G W O 5.1.0-next-20190507-autotest #1
NIP: c000000001d1e58c LR: c000000001d1e54c CTR: 0000000000000000
REGS: c000000004937890 TRAP: 0300
MSR: 8000000000009033 <SF,EE,ME,IR,DR,RI,LE> CR: 22424822 XER: 00000000
CFAR: c00000000183e9e0 DAR: 000000000000001c DSISR: 40000000 IRQMASK: 0
...
NIP kmem_cache_alloc+0xbc/0x5a0
LR kmem_cache_alloc+0x7c/0x5a0
Call Trace:
huge_pte_alloc+0x580/0x950
hugetlb_fault+0x9a0/0x1250
handle_mm_fault+0x490/0x4a0
__do_page_fault+0x77c/0x1f00
do_page_fault+0x28/0x50
handle_page_fault+0x18/0x38
This is caused by us trying to allocate from a NULL kmem cache in
__hugepte_alloc(). The kmem cache is NULL because it was never
allocated in hugetlbpage_init(), because add_huge_page_size() returned
an error.
The reason add_huge_page_size() returned an error is a simple typo, we
are calling check_and_get_huge_psize(size) when we should be passing
shift instead.
The fact that we're able to trigger this path when the kmem caches are
NULL is a separate bug, ie. we should not advertise any hugepage sizes
if we haven't setup the required caches for them.
This was only seen with 4K pages, with 64K pages we don't need to
allocate any extra kmem caches because the 16M hugepage just occupies
a single entry at the PMD level.
Fixes: 723f268f19 ("powerpc/mm: cleanup ifdef mess in add_huge_page_size()")
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Running "make kselftest" or building selftests when KBUILD_OUTPUT
is set, will create selftest objects in the KBUILD_OUTPUT directory.
This could be undesirable especially when user didn't intend to
relocate selftest objects.
Use KBUILD_OUTPUT/kselftest to create selftest objects instead of
cluttering the main directory.
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Create ../selftests/drivers/.gitignore which holds the following file name
created after compiling:
- /dma-buf/udmabuf
Signed-off-by: Kelsey Skunberg <skunberg.kelsey@gmail.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Create ../selftests/pidfd/.gitignore which holds the following file name
created after compiling:
- pidfd_test
Signed-off-by: Kelsey Skunberg <skunberg.kelsey@gmail.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Errors are negative numbers. Using %u shows them as very large positive
numbers such as 4294967277 that don't make sense. Use the %d format
instead, and get a much nicer -19.
Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Fixes: b48e0bab14 ("net: macb: Migrate to devm clock interface")
Fixes: 93b31f48b3 ("net/macb: unify clock management")
Fixes: 421d9df062 ("net/macb: merge at91_ether driver into macb driver")
Fixes: aead88bd0e ("net: ethernet: macb: Add support for rx_clk")
Fixes: f5473d1d44 ("net: macb: Support clock management for tsu_clk")
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, nla_put_iflink() doesn't put the IFLA_LINK attribute when
iflink == ifindex.
In some cases, a device can be created in a different netns with the
same ifindex as its parent. That device will not dump its IFLA_LINK
attribute, which can confuse some userspace software that expects it.
For example, if the last ifindex created in init_net and foo are both
8, these commands will trigger the issue:
ip link add parent type dummy # ifindex 9
ip link add link parent netns foo type macvlan # ifindex 9 in ns foo
So, in case a device puts the IFLA_LINK_NETNSID attribute in a dump,
always put the IFLA_LINK attribute as well.
Thanks to Dan Winship for analyzing the original OpenShift bug down to
the missing netlink attribute.
v2: change Fixes tag, it's been here forever, as Nicolas Dichtel said
add Nicolas' ack
v3: change Fixes tag
fix subject typo, spotted by Edward Cree
Analyzed-by: Dan Winship <danw@redhat.com>
Fixes: d8a5ec6727 ("[NET]: netlink support for moving devices between network namespaces.")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The error print within mlx4_flow_steer_promisc_add() should
be a info print.
Fixes: 592e49dda8 ('net/mlx4: Implement promiscuous mode with device managed flow-steering')
Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Samuel clearly hasn't been working on this in many years and
patches getting to the wireless list are just being ignored
entirely now. Mark the subsystem as orphan to reflect the
current state and revert back to the netdev list so at least
some fixes can be picked up by Dave.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jiri reported that with a kernel built with CONFIG_FIXED_PHY=y,
CONFIG_NET_DSA=m and CONFIG_NET_DSA_LOOP=m, we would not get to a
functional state where the mock-up driver is registered. Turns out that
we are not descending into drivers/net/dsa/ unconditionally, and we
won't be able to link-in dsa_loop_bdinfo.o which does the actual mock-up
mdio device registration.
Reported-by: Jiri Pirko <jiri@resnulli.us>
Fixes: 40013ff20b ("net: dsa: Fix functional dsa-loop dependency on FIXED_PHY")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Tested-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit c7d13c8faa ("tcp: properly track retry time on
passive Fast Open") sets the start of SYNACK retransmission
time on passive Fast Open in "retrans_stamp". However the
timestamp is not reset upon the handshake has completed. As a
result, future data packet retransmission may not update it in
tcp_retransmit_skb(). This may lead to socket aborting earlier
unexpectedly by retransmits_timed_out() since retrans_stamp remains
the SYNACK rtx time.
This bug only manifests on passive TFO sender that a) suffered
SYNACK timeout and then b) stalls on very first loss recovery. Any
successful loss recovery would reset the timestamp to avoid this
issue.
Fixes: c7d13c8faa ("tcp: properly track retry time on passive Fast Open")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The following warning is seen on systems with broken clock divider.
INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
CPU: 0 PID: 1 Comm: swapper Not tainted 5.1.0-09698-g1fb3b52 #1
Hardware name: ARM Integrator/CP (Device Tree)
[<c0011be8>] (unwind_backtrace) from [<c000ebb8>] (show_stack+0x10/0x18)
[<c000ebb8>] (show_stack) from [<c07d3fd0>] (dump_stack+0x18/0x24)
[<c07d3fd0>] (dump_stack) from [<c0060d48>] (register_lock_class+0x674/0x6f8)
[<c0060d48>] (register_lock_class) from [<c005de2c>]
(__lock_acquire+0x68/0x2128)
[<c005de2c>] (__lock_acquire) from [<c0060408>] (lock_acquire+0x110/0x21c)
[<c0060408>] (lock_acquire) from [<c07f755c>] (_raw_spin_lock+0x34/0x48)
[<c07f755c>] (_raw_spin_lock) from [<c0536c8c>]
(pl111_display_enable+0xf8/0x5fc)
[<c0536c8c>] (pl111_display_enable) from [<c0502f54>]
(drm_atomic_helper_commit_modeset_enables+0x1ec/0x244)
Since commit eedd6033b4 ("drm/pl111: Support variants with broken clock
divider"), the spinlock is not initialized if the clock divider is broken.
Initialize it earlier to fix the problem.
Fixes: eedd6033b4 ("drm/pl111: Support variants with broken clock divider")
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1557758781-23586-1-git-send-email-linux@roeck-us.net
When sending data, use the DMA_TO_DEVICE to map buffers. Also log the number
of requests in a compounding request from upper layer.
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
commit 214bab4484 ("cifs: Call MID callback before destroying transport")
assumes that the MID callback should not take srv_mutex, this may not always
be true. SMB Direct requires the MID callback completed before calling
transport so all pending memory registration can be freed. So restore the
original calling sequence so TCP transport will use the same code, but moving
smbd_destroy() after all MID has been called.
fixes: 214bab4484 ("cifs: Call MID callback before destroying transport")
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
The endianness of data returned from the EC depends on the particular EC
version determined at run time. Cast from little/big endian explicitey
in the routine that flips endianness to the native one to make sparse
happy.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 76311b9a32 ("power: supply: olpc_battery: Add OLPC XO 1.75 support")
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Pull virtio updates from Michael Tsirkin:
- enable packed ring support for s390
- several fixes
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio/s390: enable packed ring
virtio/s390: DMA support for virtio-ccw
virtio/s390: use vring_create_virtqueue
virtio/virtio_ring: do some comment fixes
vhost-scsi: remove incorrect memory barrier
tools/virtio/ringtest: Remove bogus definition of BUG_ON()
virtio_ring: Fix potential mem leak in virtqueue_add_indirect_packed
Commit f1b5618e01 ("vfs: Add a sample program for the new mount API")
added sample programs that get built during the kernel build, but then
cause 'git status' to worry about whether the resulting binaries should
be managed by git.
Tell git not to worry, and to ignore the sample binaries.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull more parisc updates from Helge Deller:
"Two small enhancements, which I didn't included in the last pull
request because I wanted to keep them a few more days in for-next
before sending upstream:
- Replace the ldcw barrier instruction by a nop instruction in the
CAS code on uniprocessor machines.
- Map variables read-only after init (enable ro_after_init feature)"
* 'parisc-5.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Use __ro_after_init in init.c
parisc: Use __ro_after_init in unwind.c
parisc: Use __ro_after_init in time.c
parisc: Use __ro_after_init in processor.c
parisc: Use __ro_after_init in process.c
parisc: Use __ro_after_init in perf_images.h
parisc: Use __ro_after_init in pci.c
parisc: Use __ro_after_init in inventory.c
parisc: Use __ro_after_init in head.S
parisc: Use __ro_after_init in firmware.c
parisc: Use __ro_after_init in drivers.c
parisc: Use __ro_after_init in cache.c
parisc: Enable the ro_after_init feature
parisc: Drop LDCW barrier in CAS code when running UP
Pull kgdb updates from Daniel Thompson:
"Mostly cleanups but there are also a couple of fixes for out-of-bounds
accesses (including a potential write to the byte before a static
buffer).
The main changes are:
- Fixes to those out-of-bounds access (empty string to configure test
module could write the byte before a buffer, high cpu counts could
read outside of per-cpu structures).
- Improvements to string handling problems picked up by new compiler
warnings and other static checks. Most are fixing benign issues
that can't be tickled without code changes but still reduce the wtf
factor a little.
- Tidy up the terminal output"
* tag 'kgdb-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
kdb: Fix bound check compiler warning
kdb: do a sanity check on the cpu in kdb_per_cpu()
kdb: Get rid of broken attempt to print CCVERSION in kdb summary
misc: kgdbts: fix out-of-bounds access in function param_set_kgdbts_var
kdb: kdb_support: replace strcpy() by strscpy()
gdbstub: Replace strcpy() by strscpy()
gdbstub: mark expected switch fall-throughs
Pull modules updates from Jessica Yu:
- Use a separate table to store symbol types instead of hijacking
fields in struct Elf_Sym
- Trivial code cleanups
* tag 'modules-for-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module: add stubs for within_module functions
kallsyms: store type information in its own array
vmlinux.lds.h: drop unused __vermagic
Daniel Borkmann says:
====================
This set fixes LRU map eviction in combination with map lookups out
of system call side from user space. Main patch is the second one and
test cases are adapted and added in the last one. Thanks!
====================
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The test_lru_map is relying on marking the LRU map entry via regular
BPF map lookup from system call side. This is basically for simplicity
reasons. Given we fixed marking entries in that case, the test needs
to be fixed as well. Here we add a small drop-in replacement to retain
existing behavior for the tests by marking out of the BPF program and
transferring the retrieved value out via temporary map. This also adds
new test cases to track the new behavior where two elements are marked,
one via system call side and one via program side, where the next update
then evicts the key looked up only from system call side.
# ./test_lru_map
nr_cpus:8
test_lru_sanity0 (map_type:9 map_flags:0x0): Pass
test_lru_sanity1 (map_type:9 map_flags:0x0): Pass
test_lru_sanity2 (map_type:9 map_flags:0x0): Pass
test_lru_sanity3 (map_type:9 map_flags:0x0): Pass
test_lru_sanity4 (map_type:9 map_flags:0x0): Pass
test_lru_sanity5 (map_type:9 map_flags:0x0): Pass
test_lru_sanity7 (map_type:9 map_flags:0x0): Pass
test_lru_sanity8 (map_type:9 map_flags:0x0): Pass
test_lru_sanity0 (map_type:10 map_flags:0x0): Pass
test_lru_sanity1 (map_type:10 map_flags:0x0): Pass
test_lru_sanity2 (map_type:10 map_flags:0x0): Pass
test_lru_sanity3 (map_type:10 map_flags:0x0): Pass
test_lru_sanity4 (map_type:10 map_flags:0x0): Pass
test_lru_sanity5 (map_type:10 map_flags:0x0): Pass
test_lru_sanity7 (map_type:10 map_flags:0x0): Pass
test_lru_sanity8 (map_type:10 map_flags:0x0): Pass
test_lru_sanity0 (map_type:9 map_flags:0x2): Pass
test_lru_sanity4 (map_type:9 map_flags:0x2): Pass
test_lru_sanity6 (map_type:9 map_flags:0x2): Pass
test_lru_sanity7 (map_type:9 map_flags:0x2): Pass
test_lru_sanity8 (map_type:9 map_flags:0x2): Pass
test_lru_sanity0 (map_type:10 map_flags:0x2): Pass
test_lru_sanity4 (map_type:10 map_flags:0x2): Pass
test_lru_sanity6 (map_type:10 map_flags:0x2): Pass
test_lru_sanity7 (map_type:10 map_flags:0x2): Pass
test_lru_sanity8 (map_type:10 map_flags:0x2): Pass
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
One of the biggest issues we face right now with picking LRU map over
regular hash table is that a map walk out of user space, for example,
to just dump the existing entries or to remove certain ones, will
completely mess up LRU eviction heuristics and wrong entries such
as just created ones will get evicted instead. The reason for this
is that we mark an entry as "in use" via bpf_lru_node_set_ref() from
system call lookup side as well. Thus upon walk, all entries are
being marked, so information of actual least recently used ones
are "lost".
In case of Cilium where it can be used (besides others) as a BPF
based connection tracker, this current behavior causes disruption
upon control plane changes that need to walk the map from user space
to evict certain entries. Discussion result from bpfconf [0] was that
we should simply just remove marking from system call side as no
good use case could be found where it's actually needed there.
Therefore this patch removes marking for regular LRU and per-CPU
flavor. If there ever should be a need in future, the behavior could
be selected via map creation flag, but due to mentioned reason we
avoid this here.
[0] http://vger.kernel.org/bpfconf.html
Fixes: 29ba732acb ("bpf: Add BPF_MAP_TYPE_LRU_HASH")
Fixes: 8f8449384e ("bpf: Add BPF_MAP_TYPE_LRU_PERCPU_HASH")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a callback map_lookup_elem_sys_only() that map implementations
could use over map_lookup_elem() from system call side in case the
map implementation needs to handle the latter differently than from
the BPF data path. If map_lookup_elem_sys_only() is set, this will
be preferred pick for map lookups out of user space. This hook is
used in a follow-up fix for LRU map, but once development window
opens, we can convert other map types from map_lookup_elem() (here,
the one called upon BPF_MAP_LOOKUP_ELEM cmd is meant) over to use
the callback to simplify and clean up the latter.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Merge misc updates from Andrew Morton:
- a few misc things and hotfixes
- ocfs2
- almost all of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (139 commits)
kernel/memremap.c: remove the unused device_private_entry_fault() export
mm: delete find_get_entries_tag
mm/huge_memory.c: make __thp_get_unmapped_area static
mm/mprotect.c: fix compilation warning because of unused 'mm' variable
mm/page-writeback: introduce tracepoint for wait_on_page_writeback()
mm/vmscan: simplify trace_reclaim_flags and trace_shrink_flags
mm/Kconfig: update "Memory Model" help text
mm/vmscan.c: don't disable irq again when count pgrefill for memcg
mm: memblock: make keeping memblock memory opt-in rather than opt-out
hugetlbfs: always use address space in inode for resv_map pointer
mm/z3fold.c: support page migration
mm/z3fold.c: add structure for buddy handles
mm/z3fold.c: improve compression by extending search
mm/z3fold.c: introduce helper functions
mm/page_alloc.c: remove unnecessary parameter in rmqueue_pcplist
mm/hmm: add ARCH_HAS_HMM_MIRROR ARCH_HAS_HMM_DEVICE Kconfig
mm/vmscan.c: simplify shrink_inactive_list()
fs/sync.c: sync_file_range(2) may use WB_SYNC_ALL writeback
xen/privcmd-buf.c: convert to use vm_map_pages_zero()
xen/gntdev.c: convert to use vm_map_pages()
...
The help describing the memory model selection is outdated. It still says
that SPARSEMEM is experimental and DISCONTIGMEM is a preferred over
SPARSEMEM.
Update the help text for the relevant options:
* add a generic help for the "Memory Model" prompt
* add description for FLATMEM
* reduce the description of DISCONTIGMEM and add a deprecation note
* prefer SPARSEMEM over DISCONTIGMEM
Link: http://lkml.kernel.org/r/1556188531-20728-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Continuing discussion about 58b6e5e8f1 ("hugetlbfs: fix memory leak for
resv_map") brought up the issue that inode->i_mapping may not point to the
address space embedded within the inode at inode eviction time. The
hugetlbfs truncate routine handles this by explicitly using inode->i_data.
However, code cleaning up the resv_map will still use the address space
pointed to by inode->i_mapping. Luckily, private_data is NULL for address
spaces in all such cases today but, there is no guarantee this will
continue.
Change all hugetlbfs code getting a resv_map pointer to explicitly get it
from the address space embedded within the inode. In addition, add more
comments in the code to indicate why this is being done.
Link: http://lkml.kernel.org/r/20190419204435.16984-1-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Yufen Yu <yuyufen@huawei.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that we are not using page address in handles directly, we can make
z3fold pages movable to decrease the memory fragmentation z3fold may
create over time.
This patch starts advertising non-headless z3fold pages as movable and
uses the existing kernel infrastructure to implement moving of such pages
per memory management subsystem's request. It thus implements 3 required
callbacks for page migration:
* isolation callback: z3fold_page_isolate(): try to isolate the page by
removing it from all lists. Pages scheduled for some activity and
mapped pages will not be isolated. Return true if isolation was
successful or false otherwise
* migration callback: z3fold_page_migrate(): re-check critical
conditions and migrate page contents to the new page provided by the
memory subsystem. Returns 0 on success or negative error code otherwise
* putback callback: z3fold_page_putback(): put back the page if
z3fold_page_migrate() for it failed permanently (i. e. not with
-EAGAIN code).
[lkp@intel.com: z3fold_page_isolate() can be static]
Link: http://lkml.kernel.org/r/20190419130924.GA161478@ivb42
Link: http://lkml.kernel.org/r/20190417103922.31253da5c366c4ebe0419cfc@gmail.com
Signed-off-by: Vitaly Wool <vitaly.vul@sony.com>
Signed-off-by: kbuild test robot <lkp@intel.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "z3fold: support page migration", v2.
This patchset implements page migration support and slightly better buddy
search. To implement page migration support, z3fold has to move away from
the current scheme of handle encoding. i. e. stop encoding page address
in handles. Instead, a small per-page structure is created which will
contain actual addresses for z3fold objects, while pointers to fields of
that structure will be used as handles.
Thus, it will be possible to change the underlying addresses to reflect
page migration.
To support migration itself, 3 callbacks will be implemented:
1: isolation callback: z3fold_page_isolate(): try to isolate the page
by removing it from all lists. Pages scheduled for some activity and
mapped pages will not be isolated. Return true if isolation was
successful or false otherwise
2: migration callback: z3fold_page_migrate(): re-check critical
conditions and migrate page contents to the new page provided by the
system. Returns 0 on success or negative error code otherwise
3: putback callback: z3fold_page_putback(): put back the page if
z3fold_page_migrate() for it failed permanently (i. e. not with
-EAGAIN code).
To make sure an isolated page doesn't get freed, its kref is incremented
in z3fold_page_isolate() and decremented during post-migration compaction,
if migration was successful, or by z3fold_page_putback() in the other
case.
Since the new handle encoding scheme implies slight memory consumption
increase, better buddy search (which decreases memory consumption) is
included in this patchset.
This patch (of 4):
Introduce a separate helper function for object allocation, as well as 2
smaller helpers to add a buddy to the list and to get a pointer to the
pool from the z3fold header. No functional changes here.
Link: http://lkml.kernel.org/r/20190417103633.a4bb770b5bf0fb7e43ce1666@gmail.com
Signed-off-by: Vitaly Wool <vitaly.vul@sony.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com>
Cc: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add 2 new Kconfig variables that are not used by anyone. I check that
various make ARCH=somearch allmodconfig do work and do not complain. This
new Kconfig needs to be added first so that device drivers that depend on
HMM can be updated.
Once drivers are updated then I can update the HMM Kconfig to depend on
this new Kconfig in a followup patch.
This is about solving Kconfig for HMM given that device driver are
going through their own tree we want to avoid changing them from the mm
tree. So plan is:
1 - Kernel release N add the new Kconfig to mm/Kconfig (this patch)
2 - Kernel release N+1 update driver to depend on new Kconfig ie
stop using ARCH_HASH_HMM and start using ARCH_HAS_HMM_MIRROR
and ARCH_HAS_HMM_DEVICE (one or the other or both depending
on the driver)
3 - Kernel release N+2 remove ARCH_HASH_HMM and do final Kconfig
update in mm/Kconfig
Link: http://lkml.kernel.org/r/20190417211141.17580-1-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Leon Romanovsky <leonro@mellanox.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>