Pull core block updates from Jens Axboe:
"Due to more granular branches, this one is small and will be followed
with other core branches that add specific features. I meant to just
have a core and drivers branch, but external dependencies we ended up
adding a few more that are also core.
The changes are:
- Fixes and improvements for the zoned device support (Ajay, Damien)
- sed-opal table writing and datastore UID (Revanth)
- blk-cgroup (and bfq) blk-cgroup stat fixes (Tejun)
- Improvements to the block stats tracking (Pavel)
- Fix for overruning sysfs buffer for large number of CPUs (Ming)
- Optimization for small IO (Ming, Christoph)
- Fix typo in RWH lifetime hint (Eugene)
- Dead code removal and documentation (Bart)
- Reduction in memory usage for queue and tag set (Bart)
- Kerneldoc header documentation (André)
- Device/partition revalidation fixes (Jan)
- Stats tracking for flush requests (Konstantin)
- Various other little fixes here and there (et al)"
* tag 'for-5.5/block-20191121' of git://git.kernel.dk/linux-block: (48 commits)
Revert "block: split bio if the only bvec's length is > SZ_4K"
block: add iostat counters for flush requests
block,bfq: Skip tracing hooks if possible
block: sed-opal: Introduce SUM_SET_LIST parameter and append it using 'add_token_u64'
blk-cgroup: cgroup_rstat_updated() shouldn't be called on cgroup1
block: Don't disable interrupts in trigger_softirq()
sbitmap: Delete sbitmap_any_bit_clear()
blk-mq: Delete blk_mq_has_free_tags() and blk_mq_can_queue()
block: split bio if the only bvec's length is > SZ_4K
block: still try to split bio if the bvec crosses pages
blk-cgroup: separate out blkg_rwstat under CONFIG_BLK_CGROUP_RWSTAT
blk-cgroup: reimplement basic IO stats using cgroup rstat
blk-cgroup: remove now unused blkg_print_stat_{bytes|ios}_recursive()
blk-throtl: stop using blkg->stat_bytes and ->stat_ios
bfq-iosched: stop using blkg->stat_bytes and ->stat_ios
bfq-iosched: relocate bfqg_*rwstat*() helpers
block: add zone open, close and finish ioctl support
block: add zone open, close and finish operations
block: Simplify REQ_OP_ZONE_RESET_ALL handling
block: Remove REQ_OP_ZONE_RESET plugging
...
Pull io_uring updates from Jens Axboe:
"A lot of stuff has been going on this cycle, with improving the
support for networked IO (and hence unbounded request completion
times) being one of the major themes. There's been a set of fixes done
this week, I'll send those out as well once we're certain we're fully
happy with them.
This contains:
- Unification of the "normal" submit path and the SQPOLL path (Pavel)
- Support for sparse (and bigger) file sets, and updating of those
file sets without needing to unregister/register again.
- Independently sized CQ ring, instead of just making it always 2x
the SQ ring size. This makes it more flexible for networked
applications.
- Support for overflowed CQ ring, never dropping events but providing
backpressure on submits.
- Add support for absolute timeouts, not just relative ones.
- Support for generic cancellations. This divorces io_uring from
workqueues as well, which additionally gets us one step closer to
generic async system call support.
- With cancellations, we can support grabbing the process file table
as well, just like we do mm context. This allows support for system
calls that create file descriptors, like accept4() support that's
built on top of that.
- Support for io_uring tracing (Dmitrii)
- Support for linked timeouts. These abort an operation if it isn't
completed by the time noted in the linke timeout.
- Speedup tracking of poll requests
- Various cleanups making the coder easier to follow (Jackie, Pavel,
Bob, YueHaibing, me)
- Update MAINTAINERS with new io_uring list"
* tag 'for-5.5/io_uring-20191121' of git://git.kernel.dk/linux-block: (64 commits)
io_uring: make POLL_ADD/POLL_REMOVE scale better
io-wq: remove now redundant struct io_wq_nulls_list
io_uring: Fix getting file for non-fd opcodes
io_uring: introduce req_need_defer()
io_uring: clean up io_uring_cancel_files()
io-wq: ensure free/busy list browsing see all items
io-wq: ensure we have a stable view of ->cur_work for cancellations
io_wq: add get/put_work handlers to io_wq_create()
io_uring: check for validity of ->rings in teardown
io_uring: fix potential deadlock in io_poll_wake()
io_uring: use correct "is IO worker" helper
io_uring: fix -ENOENT issue with linked timer with short timeout
io_uring: don't do flush cancel under inflight_lock
io_uring: flag SQPOLL busy condition to userspace
io_uring: make ASYNC_CANCEL work with poll and timeout
io_uring: provide fallback request for OOM situations
io_uring: convert accept4() -ERESTARTSYS into -EINTR
io_uring: fix error clear of ->file_table in io_sqe_files_register()
io_uring: separate the io_free_req and io_free_req_find_next interface
io_uring: keep io_put_req only responsible for release and put req
...
User space may request time stamps on rising edges, falling edges, or
both. However, the particular mode may or may not be supported in the
hardware or in the driver. This patch adds a "strict" flag that tells
drivers to ensure that the requested mode will be honored.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 415606588c ("PTP: introduce new versions of IOCTLs")
introduced a new external time stamp ioctl that validates the flags.
This patch extends the validation to ensure that at least one rising
or falling edge flag is set when enabling external time stamps.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When setting the dump's time-stamp, use ktime_get_real in addition to
jiffies. This simplifies the user space implementation and bypasses
some inconsistent behavior with translating jiffies to current time.
The time taken is transformed into nsec, to comply with y2038 issue.
Fixes: c8e1da0bf9 ("devlink: Add health report functionality")
Signed-off-by: Aya Levin <ayal@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) BPF sample build fixes from Björn Töpel
2) Fix powerpc bpf tail call implementation, from Eric Dumazet.
3) DCCP leaks jiffies on the wire, fix also from Eric Dumazet.
4) Fix crash in ebtables when using dnat target, from Florian Westphal.
5) Fix port disable handling whne removing bcm_sf2 driver, from Florian
Fainelli.
6) Fix kTLS sk_msg trim on fallback to copy mode, from Jakub Kicinski.
7) Various KCSAN fixes all over the networking, from Eric Dumazet.
8) Memory leaks in mlx5 driver, from Alex Vesker.
9) SMC interface refcounting fix, from Ursula Braun.
10) TSO descriptor handling fixes in stmmac driver, from Jose Abreu.
11) Add a TX lock to synchonize the kTLS TX path properly with crypto
operations. From Jakub Kicinski.
12) Sock refcount during shutdown fix in vsock/virtio code, from Stefano
Garzarella.
13) Infinite loop in Intel ice driver, from Colin Ian King.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (108 commits)
ixgbe: need_wakeup flag might not be set for Tx
i40e: need_wakeup flag might not be set for Tx
igb/igc: use ktime accessors for skb->tstamp
i40e: Fix for ethtool -m issue on X722 NIC
iavf: initialize ITRN registers with correct values
ice: fix potential infinite loop because loop counter being too small
qede: fix NULL pointer deref in __qede_remove()
net: fix data-race in neigh_event_send()
vsock/virtio: fix sock refcnt holding during the shutdown
net: ethernet: octeon_mgmt: Account for second possible VLAN header
mac80211: fix station inactive_time shortly after boot
net/fq_impl: Switch to kvmalloc() for memory allocation
mac80211: fix ieee80211_txq_setup_flows() failure path
ipv4: Fix table id reference in fib_sync_down_addr
ipv6: fixes rt6_probe() and fib6_nh->last_probe init
net: hns: Fix the stray netpoll locks causing deadlock in NAPI path
net: usb: qmi_wwan: add support for DW5821e with eSIM support
CDC-NCM: handle incomplete transfer of MTU
nfc: netlink: fix double device reference drop
NFC: st21nfca: fix double free
...
Pull block fixes from Jens Axboe:
- Two NVMe device removal crash fixes, and a compat fixup for for an
ioctl that was introduced in this release (Anton, Charles, Max - via
Keith)
- Missing error path mutex unlock for drbd (Dan)
- cgroup writeback fixup on dead memcg (Tejun)
- blkcg online stats print fix (Tejun)
* tag 'for-linus-2019-11-08' of git://git.kernel.dk/linux-block:
cgroup,writeback: don't switch wbs immediately on dead wbs if the memcg is dead
block: drbd: remove a stray unlock in __drbd_send_protocol()
blkcg: make blkcg_print_stat() print stats only for online blkgs
nvme: change nvme_passthru_cmd64 to explicitly mark rsvd
nvme-multipath: fix crash in nvme_mpath_clear_ctrl_paths
nvme-rdma: fix a segmentation fault during module unload
Pull on for-linus to resolve what otherwise would have been a conflict
with the cgroups rstat patchset from Tejun.
* for-linus: (942 commits)
blkcg: make blkcg_print_stat() print stats only for online blkgs
nvme: change nvme_passthru_cmd64 to explicitly mark rsvd
nvme-multipath: fix crash in nvme_mpath_clear_ctrl_paths
nvme-rdma: fix a segmentation fault during module unload
iocost: don't nest spin_lock_irq in ioc_weight_write()
io_uring: ensure we clear io_kiocb->result before each issue
um-ubd: Entrust re-queue to the upper layers
nvme-multipath: remove unused groups_only mode in ana log
nvme-multipath: fix possible io hang after ctrl reconnect
io_uring: don't touch ctx in setup after ring fd install
io_uring: Fix leaked shadow_req
Linux 5.4-rc5
riscv: cleanup do_trap_break
nbd: verify socket is supported during setup
ata: libahci_platform: Fix regulator_get_optional() misuse
nbd: handle racing with error'ed out commands
nbd: protect cmd->status with cmd->lock
io_uring: fix bad inflight accounting for SETUP_IOPOLL|SETUP_SQTHREAD
io_uring: used cached copies of sq->dropped and cq->overflow
ARM: dts: stm32: relax qspi pins slew-rate for stm32mp157
...
Currently we drop completion events, if the CQ ring is full. That's fine
for requests with bounded completion times, but it may make it harder or
impossible to use io_uring with networked IO where request completion
times are generally unbounded. Or with POLL, for example, which is also
unbounded.
After this patch, we never overflow the ring, we simply store requests
in a backlog for later flushing. This flushing is done automatically by
the kernel. To prevent the backlog from growing indefinitely, if the
backlog is non-empty, we apply back pressure on IO submissions. Any
attempt to submit new IO with a non-empty backlog will get an -EBUSY
return from the kernel. This is a signal to the application that it has
backlogged CQ events, and that it must reap those before being allowed
to submit more IO.
Note that if we do return -EBUSY, we will have filled whatever
backlogged events into the CQ ring first, if there's room. This means
the application can safely reap events WITHOUT entering the kernel and
waiting for them, they are already available in the CQ ring.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
While we have support for generic timeouts, we don't have a way to tie
a timeout to a specific SQE. The generic timeouts simply trigger wakeups
on the CQ ring.
This adds support for IORING_OP_LINK_TIMEOUT. This command is only valid
as a link to a previous command. The timeout specific can be either
relative or absolute, following the same rules as IORING_OP_TIMEOUT. If
the timeout triggers before the dependent command completes, it will
attempt to cancel that command. Likewise, if the dependent command
completes before the timeout triggers, it will cancel the timeout.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Introduce three new ioctl commands BLKOPENZONE, BLKCLOSEZONE and
BLKFINISHZONE to allow applications to control the condition of zones
on a zoned block device through the execution of the REQ_OP_ZONE_OPEN,
REQ_OP_ZONE_CLOSE and REQ_OP_ZONE_FINISH operations.
Contains contributions from Matias Bjorling, Hans Holmberg,
Dmitry Fomichev, Keith Busch, Damien Le Moal and Christoph Hellwig.
Reviewed-by: Javier González <javier@javigon.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ajay Joshi <ajay.joshi@wdc.com>
Signed-off-by: Matias Bjorling <matias.bjorling@wdc.com>
Signed-off-by: Hans Holmberg <hans.holmberg@wdc.com>
Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Changing nvme_passthru_cmd64 to add a field: rsvd2. This field is an explicit
marker for the padding space added on certain platforms as a result of the
enlargement of the result field from 32 bit to 64 bits in size, and
fixes differences in struct size when using compat ioctl for 32-bit
binaries on 64-bit architecture.
Fixes: 65e68edce0 ("nvme: allow 64-bit results in passthru commands")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Charles Machalow <csm10495@gmail.com>
[changelog]
Signed-off-by: Keith Busch <kbusch@kernel.org>
Pull clone3 stack argument update from Christian Brauner:
"This changes clone3() to do basic stack validation and to set up the
stack depending on whether or not it is growing up or down.
With clone3() the expectation is now very simply that the .stack
argument points to the lowest address of the stack and that
.stack_size specifies the initial stack size. This is diferent from
legacy clone() where the "stack" argument had to point to the lowest
or highest address of the stack depending on the architecture.
clone3() was released with 5.3. Currently, it is not documented and
very unclear to userspace how the stack and stack_size argument have
to be passed. After talking to glibc folks we concluded that changing
clone3() to determine stack direction and doing basic validation is
the right course of action.
Note, this is a potentially user visible change. In the very unlikely
case, that it breaks someone's use-case we will revert. (And then e.g.
place the new behavior under an appropriate flag.)
Note that passing an empty stack will continue working just as before.
Breaking someone's use-case is very unlikely. Neither glibc nor musl
currently expose a wrapper for clone3(). There is currently also no
real motivation for anyone to use clone3() directly. First, because
using clone{3}() with stacks requires some assembly (see glibc and
musl). Second, because it does not provide features that legacy
clone() doesn't. New features for clone3() will first happen in v5.5
which is why v5.4 is still a good time to try and make that change now
and backport it to v5.3.
I did a codesearch on https://codesearch.debian.net, github, and
gitlab and could not find any software currently relying directly on
clone3(). I expect this to change once we land CLONE_CLEAR_SIGHAND
which was a request coming from glibc at which point they'll likely
start using it"
* tag 'for-linus-2019-11-05' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
clone3: validate stack arguments
Validate the stack arguments and setup the stack depening on whether or not
it is growing down or up.
Legacy clone() required userspace to know in which direction the stack is
growing and pass down the stack pointer appropriately. To make things more
confusing microblaze uses a variant of the clone() syscall selected by
CONFIG_CLONE_BACKWARDS3 that takes an additional stack_size argument.
IA64 has a separate clone2() syscall which also takes an additional
stack_size argument. Finally, parisc has a stack that is growing upwards.
Userspace therefore has a lot nasty code like the following:
#define __STACK_SIZE (8 * 1024 * 1024)
pid_t sys_clone(int (*fn)(void *), void *arg, int flags, int *pidfd)
{
pid_t ret;
void *stack;
stack = malloc(__STACK_SIZE);
if (!stack)
return -ENOMEM;
#ifdef __ia64__
ret = __clone2(fn, stack, __STACK_SIZE, flags | SIGCHLD, arg, pidfd);
#elif defined(__parisc__) /* stack grows up */
ret = clone(fn, stack, flags | SIGCHLD, arg, pidfd);
#else
ret = clone(fn, stack + __STACK_SIZE, flags | SIGCHLD, arg, pidfd);
#endif
return ret;
}
or even crazier variants such as [3].
With clone3() we have the ability to validate the stack. We can check that
when stack_size is passed, the stack pointer is valid and the other way
around. We can also check that the memory area userspace gave us is fine to
use via access_ok(). Furthermore, we probably should not require
userspace to know in which direction the stack is growing. It is easy
for us to do this in the kernel and I couldn't find the original
reasoning behind exposing this detail to userspace.
/* Intentional user visible API change */
clone3() was released with 5.3. Currently, it is not documented and very
unclear to userspace how the stack and stack_size argument have to be
passed. After talking to glibc folks we concluded that trying to change
clone3() to setup the stack instead of requiring userspace to do this is
the right course of action.
Note, that this is an explicit change in user visible behavior we introduce
with this patch. If it breaks someone's use-case we will revert! (And then
e.g. place the new behavior under an appropriate flag.)
Breaking someone's use-case is very unlikely though. First, neither glibc
nor musl currently expose a wrapper for clone3(). Second, there is no real
motivation for anyone to use clone3() directly since it does not provide
features that legacy clone doesn't. New features for clone3() will first
happen in v5.5 which is why v5.4 is still a good time to try and make that
change now and backport it to v5.3. Searches on [4] did not reveal any
packages calling clone3().
[1]: https://lore.kernel.org/r/CAG48ez3q=BeNcuVTKBN79kJui4vC6nw0Bfq6xc-i0neheT17TA@mail.gmail.com
[2]: https://lore.kernel.org/r/20191028172143.4vnnjpdljfnexaq5@wittgenstein
[3]: 5238e95759/src/basic/raw-clone.h (L31)
[4]: https://codesearch.debian.net
Fixes: 7f192e3cd3 ("fork: add clone3")
Cc: Kees Cook <keescook@chromium.org>
Cc: Jann Horn <jannh@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-api@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # 5.3
Cc: GNU C Library <libc-alpha@sourceware.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Aleksa Sarai <cyphar@cyphar.com>
Link: https://lore.kernel.org/r/20191031113608.20713-1-christian.brauner@ubuntu.com
This feature gives the user RW access to any opal table with admin1
authority. The flags described in the new structure determines if the user
wants to read/write the data. Flags are checked for valid values in
order to allow future features to be added to the ioctl.
The user can provide the desired table's UID. Also, the ioctl provides a
size and offset field and internally will loop data accesses to return
the full data block. Read overrun is prevented by the initiator's
sec_send_recv() backend. The ioctl provides a private field with the
intention to accommodate any future expansions to the ioctl.
Reviewed-by: Scott Bauer <sbauer@plzdonthack.me>
Reviewed-by: Jon Derrick <jonathan.derrick@intel.com>
Signed-off-by: Revanth Rajashekar <revanth.rajashekar@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This adds support for IORING_OP_ASYNC_CANCEL, which will attempt to
cancel requests that have been punted to async context and are now
in-flight. This works for regular read/write requests to files, as
long as they haven't been started yet. For socket based IO (or things
like accept4(2)), we can cancel work that is already running as well.
To cancel a request, the sqe must have ->addr set to the user_data of
the request it wishes to cancel. If the request is cancelled
successfully, the original request is completed with -ECANCELED
and the cancel request is completed with a result of 0. If the
request was already running, the original may or may not complete
in error. The cancel request will complete with -EALREADY for that
case. And finally, if the request to cancel wasn't found, the cancel
request is completed with -ENOENT.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This allows an application to call accept4() in an async fashion. Like
other opcodes, we first try a non-blocking accept, then punt to async
context if we have to.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull fuse fixes from Miklos Szeredi:
"Mostly virtiofs fixes, but also fixes a regression and couple of
longstanding data/metadata writeback ordering issues"
* tag 'fuse-fixes-5.4-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
fuse: redundant get_fuse_inode() calls in fuse_writepages_fill()
fuse: Add changelog entries for protocols 7.1 - 7.8
fuse: truncate pending writes on O_TRUNC
fuse: flush dirty data/metadata before non-truncate setattr
virtiofs: Remove set but not used variable 'fc'
virtiofs: Retry request submission from worker context
virtiofs: Count pending forgets as in_flight forgets
virtiofs: Set FR_SENT flag only after request has been sent
virtiofs: No need to check fpq->connected state
virtiofs: Do not end request in submission context
fuse: don't advise readdirplus for negative lookup
fuse: don't dereference req->args on finished request
virtio-fs: don't show mount options
virtio-fs: Change module name to virtiofs.ko
We might have cases where the need for a specific timeout is gone, add
support for canceling an existing timeout operation. This works like the
POLL_REMOVE command, where the application passes in the user_data of
the timeout it wishes to cancel in the sqe->addr field.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is a pretty trivial addition on top of the relative timeouts
we have now, but it's handy for ensuring tighter timing for those
that are building scheduling primitives on top of io_uring.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We currently size the CQ ring as twice the SQ ring, to allow some
flexibility in not overflowing the CQ ring. This is done because the
SQE life time is different than that of the IO request itself, the SQE
is consumed as soon as the kernel has seen the entry.
Certain application don't need a huge SQ ring size, since they just
submit IO in batches. But they may have a lot of requests pending, and
hence need a big CQ ring to hold them all. By allowing the application
to control the CQ ring size multiplier, we can cater to those
applications more efficiently.
If an application wants to define its own CQ ring size, it must set
IORING_SETUP_CQSIZE in the setup flags, and fill out
io_uring_params->cq_entries. The value must be a power of two.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Allows the application to remove/replace/add files to/from a file set.
Passes in a struct:
struct io_uring_files_update {
__u32 offset;
__s32 *fds;
};
that holds an array of fds, size of array passed in through the usual
nr_args part of the io_uring_register() system call. The logic is as
follows:
1) If ->fds[i] is -1, the existing file at i + ->offset is removed from
the set.
2) If ->fds[i] is a valid fd, the existing file at i + ->offset is
replaced with ->fds[i].
For case #2, is the existing file is currently empty (fd == -1), the
new fd is simply added to the array.
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull tty/serial driver fixes from Greg KH:
"Here are some small tty and serial driver fixes for 5.4-rc3 that
resolve a number of reported issues and regressions.
None of these are huge, full details are in the shortlog. There's also
a MAINTAINERS update that I think you might have already taken in your
tree already, but git should handle that merge easily.
All have been in linux-next with no reported issues"
* tag 'tty-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
MAINTAINERS: kgdb: Add myself as a reviewer for kgdb/kdb
tty: serial: imx: Use platform_get_irq_optional() for optional IRQs
serial: fix kernel-doc warning in comments
serial: 8250_omap: Fix gpio check for auto RTS/CTS
serial: mctrl_gpio: Check for NULL pointer
tty: serial: fsl_lpuart: Fix lpuart_flush_buffer()
tty: serial: Fix PORT_LINFLEXUART definition
tty: n_hdlc: fix build on SPARC
serial: uartps: Fix uartps_major handling
serial: uartlite: fix exit path null pointer
tty: serial: linflexuart: Fix magic SysRq handling
serial: sh-sci: Use platform_get_irq_optional() for optional interrupts
dt-bindings: serial: sh-sci: Document r8a774b1 bindings
serial/sifive: select SERIAL_EARLYCON
tty: serial: rda: Fix the link time qualifier of 'rda_uart_exit()'
tty: serial: owl: Fix the link time qualifier of 'owl_uart_exit()'
Pull copy_struct_from_user() helper from Christian Brauner:
"This contains the copy_struct_from_user() helper which got split out
from the openat2() patchset. It is a generic interface designed to
copy a struct from userspace.
The helper will be especially useful for structs versioned by size of
which we have quite a few. This allows for backwards compatibility,
i.e. an extended struct can be passed to an older kernel, or a legacy
struct can be passed to a newer kernel. For the first case (extended
struct, older kernel) the new fields in an extended struct can be set
to zero and the struct safely passed to an older kernel.
The most obvious benefit is that this helper lets us get rid of
duplicate code present in at least sched_setattr(), perf_event_open(),
and clone3(). More importantly it will also help to ensure that users
implementing versioning-by-size end up with the same core semantics.
This point is especially crucial since we have at least one case where
versioning-by-size is used but with slighly different semantics:
sched_setattr(), perf_event_open(), and clone3() all do do similar
checks to copy_struct_from_user() while rt_sigprocmask(2) always
rejects differently-sized struct arguments.
With this pull request we also switch over sched_setattr(),
perf_event_open(), and clone3() to use the new helper"
* tag 'copy-struct-from-user-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
usercopy: Add parentheses around assignment in test_copy_struct_from_user
perf_event_open: switch to copy_struct_from_user()
sched_setattr: switch to copy_struct_from_user()
clone3: switch to copy_struct_from_user()
lib: introduce copy_struct_from_user() helper
Pull clone3/pidfd fixes from Christian Brauner:
"This contains a couple of fixes:
- Fix pidfd selftest compilation (Shuah Kahn)
Due to a false linking instruction in the Makefile compilation for
the pidfd selftests would fail on some systems.
- Fix compilation for glibc on RISC-V systems (Seth Forshee)
In some scenarios linux/uapi/linux/sched.h is included where
__ASSEMBLY__ is defined causing a build failure because struct
clone_args was not guarded by an #ifndef __ASSEMBLY__.
- Add missing clone3() and struct clone_args kernel-doc (Christian Brauner)
clone3() and struct clone_args were missing kernel-docs. (The goal
is to use kernel-doc for any function or type where it's worth it.)
For struct clone_args this also contains a comment about the fact
that it's versioned by size"
* tag 'for-linus-20191003' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
sched: add kernel-doc for struct clone_args
fork: add kernel-doc for clone3
selftests: pidfd: Fix undefined reference to pthread_create()
sched: Add __ASSEMBLY__ guards around struct clone_args
Pull drm fixes from Dave Airlie:
"Been offline for 3 days, got back and had some fixes queued up.
Nothing too major, the i915 dp-mst fix is important, and amdgpu has a
bulk move speedup fix and some regressions, but nothing too insane for
an rc2 pull. The intel fixes are also 2 weeks worth, they missed the
boat last week.
core:
- writeback fixes
i915:
- Fix DP-MST crtc_mask
- Fix dsc dpp calculations
- Fix g4x sprite scaling stride check with GTT remapping
- Fix concurrence on cases where requests where getting retired at
same time as resubmitted to HW
- Fix gen9 display resolutions by setting the right max plane width
- Fix GPU hang on preemption
- Mark contents as dirty on a write fault. This was breaking cursor
sprite with dumb buffers.
komeda:
- memory leak fix
tilcdc:
- include fix
amdgpu:
- Enable bulk moves
- Power metrics fixes for Navi
- Fix S4 regression
- Add query for tcc disabled mask
- Fix several leaks in error paths
- randconfig fixes
- clang fixes"
* tag 'drm-fixes-2019-10-04' of git://anongit.freedesktop.org/drm/drm: (21 commits)
Revert "drm/i915: Fix DP-MST crtc_mask"
drm/omap: fix max fclk divider for omap36xx
drm/i915: Fix g4x sprite scaling stride check with GTT remapping
drm/i915/dp: Fix dsc bpp calculations, v5.
drm/amd/display: fix dcn21 Makefile for clang
drm/amd/display: hide an unused variable
drm/amdgpu: display_mode_vba_21: remove uint typedef
drm/amdgpu: hide another #warning
drm/amdgpu: make pmu support optional, again
drm/amd/display: memory leak
drm/amdgpu: fix multiple memory leaks in acp_hw_init
drm/amdgpu: return tcc_disabled_mask to userspace
drm/amdgpu: don't increment vram lost if we are in hibernation
Revert "drm/amdgpu: disable stutter mode for renoir"
drm/amd/powerplay: add sensor lock support for smu
drm/amd/powerplay: change metrics update period from 1ms to 100ms
drm/amdgpu: revert "disable bulk moves for now"
drm/tilcdc: include linux/pinctrl/consumer.h again
drm/komeda: prevent memory leak in komeda_wb_connector_add
drm: Clear the fence pointer when writeback job signaled
...
Pull block fixes from Jens Axboe:
- Mandate timespec64 for the io_uring timeout ABI (Arnd)
- Set of NVMe changes via Sagi:
- controller removal race fix from Balbir
- quirk additions from Gabriel and Jian-Hong
- nvme-pci power state save fix from Mario
- Add 64bit user commands (for 64bit registers) from Marta
- nvme-rdma/nvme-tcp fixes from Max, Mark and Me
- Minor cleanups and nits from James, Dan and John
- Two s390 dasd fixes (Jan, Stefan)
- Have loop change block size in DIO mode (Martijn)
- paride pg header ifdef guard (Masahiro)
- Two blk-mq queue scheduler tweaks, fixing an ordering issue on zoned
devices and suboptimal performance on others (Ming)
* tag 'for-linus-2019-10-03' of git://git.kernel.dk/linux-block: (22 commits)
block: sed-opal: fix sparse warning: convert __be64 data
block: sed-opal: fix sparse warning: obsolete array init.
block: pg: add header include guard
Revert "s390/dasd: Add discard support for ESE volumes"
s390/dasd: Fix error handling during online processing
io_uring: use __kernel_timespec in timeout ABI
loop: change queue block size to match when using DIO
blk-mq: apply normal plugging for HDD
blk-mq: honor IO scheduler for multiqueue devices
nvme-rdma: fix possible use-after-free in connect timeout
nvme: Move ctrl sqsize to generic space
nvme: Add ctrl attributes for queue_count and sqsize
nvme: allow 64-bit results in passthru commands
nvme: Add quirk for Kingston NVME SSD running FW E8FK11.T
nvmet-tcp: remove superflous check on request sgl
Added QUIRKs for ADATA XPG SX8200 Pro 512GB
nvme-rdma: Fix max_hw_sectors calculation
nvme: fix an error code in nvme_init_subsystem()
nvme-pci: Save PCI state before putting drive into deepest state
nvme-tcp: fix wrong stop condition in io_work
...
Switch clone3() syscall from it's own copying struct clone_args from
userspace to the new dedicated copy_struct_from_user() helper.
The change is very straightforward, and helps unify the syscall
interface for struct-from-userspace syscalls. Additionally, explicitly
define CLONE_ARGS_SIZE_VER0 to match the other users of the
struct-extension pattern.
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
[christian.brauner@ubuntu.com: improve commit message]
Link: https://lore.kernel.org/r/20191001011055.19283-3-cyphar@cyphar.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Pull networking fixes from David Miller:
1) Sanity check URB networking device parameters to avoid divide by
zero, from Oliver Neukum.
2) Disable global multicast filter in NCSI, otherwise LLDP and IPV6
don't work properly. Longer term this needs a better fix tho. From
Vijay Khemka.
3) Small fixes to selftests (use ping when ping6 is not present, etc.)
from David Ahern.
4) Bring back rt_uses_gateway member of struct rtable, it's semantics
were not well understood and trying to remove it broke things. From
David Ahern.
5) Move usbnet snaity checking, ignore endpoints with invalid
wMaxPacketSize. From Bjørn Mork.
6) Missing Kconfig deps for sja1105 driver, from Mao Wenan.
7) Various small fixes to the mlx5 DR steering code, from Alaa Hleihel,
Alex Vesker, and Yevgeny Kliteynik
8) Missing CAP_NET_RAW checks in various places, from Ori Nimron.
9) Fix crash when removing sch_cbs entry while offloading is enabled,
from Vinicius Costa Gomes.
10) Signedness bug fixes, generally in looking at the result given by
of_get_phy_mode() and friends. From Dan Crapenter.
11) Disable preemption around BPF_PROG_RUN() calls, from Eric Dumazet.
12) Don't create VRF ipv6 rules if ipv6 is disabled, from David Ahern.
13) Fix quantization code in tcp_bbr, from Kevin Yang.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (127 commits)
net: tap: clean up an indentation issue
nfp: abm: fix memory leak in nfp_abm_u32_knode_replace
tcp: better handle TCP_USER_TIMEOUT in SYN_SENT state
sk_buff: drop all skb extensions on free and skb scrubbing
tcp_bbr: fix quantization code to not raise cwnd if not probing bandwidth
mlxsw: spectrum_flower: Fail in case user specifies multiple mirror actions
Documentation: Clarify trap's description
mlxsw: spectrum: Clear VLAN filters during port initialization
net: ena: clean up indentation issue
NFC: st95hf: clean up indentation issue
net: phy: micrel: add Asym Pause workaround for KSZ9021
net: socionext: ave: Avoid using netdev_err() before calling register_netdev()
ptp: correctly disable flags on old ioctls
lib: dimlib: fix help text typos
net: dsa: microchip: Always set regmap stride to 1
nfp: flower: fix memory leak in nfp_flower_spawn_vnic_reprs
nfp: flower: prevent memory leak in nfp_flower_spawn_phy_reprs
net/sched: Set default of CONFIG_NET_TC_SKB_EXT to N
vrf: Do not attempt to create IPv6 mcast rule if IPv6 is disabled
net: sched: sch_sfb: don't call qdisc_put() while holding tree lock
...
Pull nfsd updates from Bruce Fields:
"Highlights:
- Add a new knfsd file cache, so that we don't have to open and close
on each (NFSv2/v3) READ or WRITE. This can speed up read and write
in some cases. It also replaces our readahead cache.
- Prevent silent data loss on write errors, by treating write errors
like server reboots for the purposes of write caching, thus forcing
clients to resend their writes.
- Tweak the code that allocates sessions to be more forgiving, so
that NFSv4.1 mounts are less likely to hang when a server already
has a lot of clients.
- Eliminate an arbitrary limit on NFSv4 ACL sizes; they should now be
limited only by the backend filesystem and the maximum RPC size.
- Allow the server to enforce use of the correct kerberos credentials
when a client reclaims state after a reboot.
And some miscellaneous smaller bugfixes and cleanup"
* tag 'nfsd-5.4' of git://linux-nfs.org/~bfields/linux: (34 commits)
sunrpc: clean up indentation issue
nfsd: fix nfs read eof detection
nfsd: Make nfsd_reset_boot_verifier_locked static
nfsd: degraded slot-count more gracefully as allocation nears exhaustion.
nfsd: handle drc over-allocation gracefully.
nfsd: add support for upcall version 2
nfsd: add a "GetVersion" upcall for nfsdcld
nfsd: Reset the boot verifier on all write I/O errors
nfsd: Don't garbage collect files that might contain write errors
nfsd: Support the server resetting the boot verifier
nfsd: nfsd_file cache entries should be per net namespace
nfsd: eliminate an unnecessary acl size limit
Deprecate nfsd fault injection
nfsd: remove duplicated include from filecache.c
nfsd: Fix the documentation for svcxdr_tmpalloc()
nfsd: Fix up some unused variable warnings
nfsd: close cached files prior to a REMOVE or RENAME that would replace target
nfsd: rip out the raparms cache
nfsd: have nfsd_test_lock use the nfsd_file cache
nfsd: hook up nfs4_preprocess_stateid_op to the nfsd_file cache
...
Pull fuse virtio-fs support from Miklos Szeredi:
"Virtio-fs allows exporting directory trees on the host and mounting
them in guest(s).
This isn't actually a new filesystem, but a glue layer between the
fuse filesystem and a virtio based back-end.
It's similar in functionality to the existing virtio-9p solution, but
significantly faster in benchmarks and has better POSIX compliance.
Further permformance improvements can be achieved by sharing the page
cache between host and guest, allowing for faster I/O and reduced
memory use.
Kata Containers have been including the out-of-tree virtio-fs (with
the shared page cache patches as well) since version 1.7 as an
experimental feature. They have been active in development and plan to
switch from virtio-9p to virtio-fs as their default solution. There
has been interest from other sources as well.
The userspace infrastructure is slated to be merged into qemu once the
kernel part hits mainline.
This was developed by Vivek Goyal, Dave Gilbert and Stefan Hajnoczi"
* tag 'virtio-fs-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
virtio-fs: add virtiofs filesystem
virtio-fs: add Documentation/filesystems/virtiofs.rst
fuse: reserve values for mapping protocol
Pull more RISC-V updates from Paul Walmsley:
"Some additional RISC-V updates.
This includes one significant fix:
- Prevent interrupts from being unconditionally re-enabled during
exception handling if they were disabled in the context in which
the exception occurred
Also a few other fixes:
- Fix a build error when sparse memory support is manually enabled
- Prevent CPUs beyond CONFIG_NR_CPUS from being enabled in early boot
And a few minor improvements:
- DT improvements: in the FU540 SoC DT files, improve U-Boot
compatibility by adding an "ethernet0" alias, drop an unnecessary
property from the DT files, and add support for the PWM device
- KVM preparation: add a KVM-related macro for future RISC-V KVM
support, and export some symbols required to build KVM support as
modules
- defconfig additions: build more drivers by default for QEMU
configurations"
* tag 'riscv/for-v5.4-rc1-b' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Avoid interrupts being erroneously enabled in handle_exception()
riscv: dts: sifive: Drop "clock-frequency" property of cpu nodes
riscv: dts: sifive: Add ethernet0 to the aliases node
RISC-V: Export kernel symbols for kvm
KVM: RISC-V: Add KVM_REG_RISCV for ONE_REG interface
arch/riscv: disable excess harts before picking main boot hart
RISC-V: Enable VIRTIO drivers in RV64 and RV32 defconfig
RISC-V: Fix building error when CONFIG_SPARSEMEM_MANUAL=y
riscv: dts: Add DT support for SiFive FU540 PWM driver
Pull more KVM updates from Paolo Bonzini:
"x86 KVM changes:
- The usual accuracy improvements for nested virtualization
- The usual round of code cleanups from Sean
- Added back optimizations that were prematurely removed in 5.2 (the
bare minimum needed to fix the regression was in 5.3-rc8, here
comes the rest)
- Support for UMWAIT/UMONITOR/TPAUSE
- Direct L2->L0 TLB flushing when L0 is Hyper-V and L1 is KVM
- Tell Windows guests if SMT is disabled on the host
- More accurate detection of vmexit cost
- Revert a pvqspinlock pessimization"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (56 commits)
KVM: nVMX: cleanup and fix host 64-bit mode checks
KVM: vmx: fix build warnings in hv_enable_direct_tlbflush() on i386
KVM: x86: Don't check kvm_rebooting in __kvm_handle_fault_on_reboot()
KVM: x86: Drop ____kvm_handle_fault_on_reboot()
KVM: VMX: Add error handling to VMREAD helper
KVM: VMX: Optimize VMX instruction error and fault handling
KVM: x86: Check kvm_rebooting in kvm_spurious_fault()
KVM: selftests: fix ucall on x86
Revert "locking/pvqspinlock: Don't wait if vCPU is preempted"
kvm: nvmx: limit atomic switch MSRs
kvm: svm: Intercept RDPRU
kvm: x86: Add "significant index" flag to a few CPUID leaves
KVM: x86/mmu: Skip invalid pages during zapping iff root_count is zero
KVM: x86/mmu: Explicitly track only a single invalid mmu generation
KVM: x86/mmu: Revert "KVM: x86/mmu: Remove is_obsolete() call"
KVM: x86/mmu: Revert "Revert "KVM: MMU: reclaim the zapped-obsolete page first""
KVM: x86/mmu: Revert "Revert "KVM: MMU: collapse TLB flushes when zap all pages""
KVM: x86/mmu: Revert "Revert "KVM: MMU: zap pages in batch""
KVM: x86/mmu: Revert "Revert "KVM: MMU: add tracepoint for kvm_mmu_invalidate_all_pages""
KVM: x86/mmu: Revert "Revert "KVM: MMU: show mmu_valid_gen in shadow page related tracepoints""
...
Pull NVMe changes from Sagi:
"This set consists of various fixes and cleanups:
- controller removal race fix from Balbir
- quirk additions from Gabriel and Jian-Hong
- nvme-pci power state save fix from Mario
- Add 64bit user commands (for 64bit registers) from Marta
- nvme-rdma/nvme-tcp fixes from Max, Mark and Me
- Minor cleanups and nits from James, Dan and John"
* 'nvme-5.4' of git://git.infradead.org/nvme:
nvme-rdma: fix possible use-after-free in connect timeout
nvme: Move ctrl sqsize to generic space
nvme: Add ctrl attributes for queue_count and sqsize
nvme: allow 64-bit results in passthru commands
nvme: Add quirk for Kingston NVME SSD running FW E8FK11.T
nvmet-tcp: remove superflous check on request sgl
Added QUIRKs for ADATA XPG SX8200 Pro 512GB
nvme-rdma: Fix max_hw_sectors calculation
nvme: fix an error code in nvme_init_subsystem()
nvme-pci: Save PCI state before putting drive into deepest state
nvme-tcp: fix wrong stop condition in io_work
nvme-pci: Fix a race in controller removal
nvmet: change ppl to lpp
Commit 415606588c ("PTP: introduce new versions of IOCTLs",
2019-09-13) introduced new versions of the PTP ioctls which actually
validate that the flags are acceptable values.
As part of this, it cleared the flags value using a bitwise
and+negation, in an attempt to prevent the old ioctl from accidentally
enabling new features.
This is incorrect for a couple of reasons. First, it results in
accidentally preventing previously working flags on the request ioctl.
By clearing the "valid" flags, we now no longer allow setting the
enable, rising edge, or falling edge flags.
Second, if we add new additional flags in the future, they must not be
set by the old ioctl. (Since the flag wasn't checked before, we could
potentially break userspace programs which sent garbage flag data.
The correct way to resolve this is to check for and clear all but the
originally valid flags.
Create defines indicating which flags are correctly checked and
interpreted by the original ioctls. Use these to clear any bits which
will not be correctly interpreted by the original ioctls.
In the future, new flags must be added to the VALID_FLAGS macros, but
*not* to the V1_VALID_FLAGS macros. In this way, new features may be
exposed over the v2 ioctls, but without breaking previous userspace
which happened to not clear the flags value properly. The old ioctl will
continue to behave the same way, while the new ioctl gains the benefit
of using the flags fields.
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Christopher Hall <christopher.s.hall@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for net:
1) Add NFT_CHAIN_POLICY_UNSET to replace hardcoded -1 to
specify that the chain policy is unset. The chain policy
field is actually defined as an 8-bit unsigned integer.
2) Remove always true condition reported by smatch in
chain policy check.
3) Fix element lookup on dynamic sets, from Florian Westphal.
4) Use __u8 in ebtables uapi header, from Masahiro Yamada.
5) Bogus EBUSY when removing flowtable after chain flush,
from Laura Garcia Liebana.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge more updates from Andrew Morton:
- almost all of the rest of -mm
- various other subsystems
Subsystems affected by this patch series:
memcg, misc, core-kernel, lib, checkpatch, reiserfs, fat, fork,
cpumask, kexec, uaccess, kconfig, kgdb, bug, ipc, lzo, kasan, madvise,
cleanups, pagemap
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (77 commits)
arch/sparc/include/asm/pgtable_64.h: fix build
mm: treewide: clarify pgtable_page_{ctor,dtor}() naming
ntfs: remove (un)?likely() from IS_ERR() conditions
IB/hfi1: remove unlikely() from IS_ERR*() condition
xfs: remove unlikely() from WARN_ON() condition
wimax/i2400m: remove unlikely() from WARN*() condition
fs: remove unlikely() from WARN_ON() condition
xen/events: remove unlikely() from WARN() condition
checkpatch: check for nested (un)?likely() calls
hexagon: drop empty and unused free_initrd_mem
mm: factor out common parts between MADV_COLD and MADV_PAGEOUT
mm: introduce MADV_PAGEOUT
mm: change PAGEREF_RECLAIM_CLEAN with PAGE_REFRECLAIM
mm: introduce MADV_COLD
mm: untag user pointers in mmap/munmap/mremap/brk
vfio/type1: untag user pointers in vaddr_get_pfn
tee/shm: untag user pointers in tee_shm_register
media/v4l2-core: untag user pointers in videobuf_dma_contig_user_get
drm/radeon: untag user pointers in radeon_gem_userptr_ioctl
drm/amdgpu: untag user pointers
...
When a process expects no accesses to a certain memory range for a long
time, it could hint kernel that the pages can be reclaimed instantly but
data should be preserved for future use. This could reduce workingset
eviction so it ends up increasing performance.
This patch introduces the new MADV_PAGEOUT hint to madvise(2) syscall.
MADV_PAGEOUT can be used by a process to mark a memory range as not
expected to be used for a long time so that kernel reclaims *any LRU*
pages instantly. The hint can help kernel in deciding which pages to
evict proactively.
A note: It doesn't apply SWAP_CLUSTER_MAX LRU page isolation limit
intentionally because it's automatically bounded by PMD size. If PMD
size(e.g., 256) makes some trouble, we could fix it later by limit it to
SWAP_CLUSTER_MAX[1].
- man-page material
MADV_PAGEOUT (since Linux x.x)
Do not expect access in the near future so pages in the specified
regions could be reclaimed instantly regardless of memory pressure.
Thus, access in the range after successful operation could cause
major page fault but never lose the up-to-date contents unlike
MADV_DONTNEED. Pages belonging to a shared mapping are only processed
if a write access is allowed for the calling process.
MADV_PAGEOUT cannot be applied to locked pages, Huge TLB pages, or
VM_PFNMAP pages.
[1] https://lore.kernel.org/lkml/20190710194719.GS29695@dhcp22.suse.cz/
[minchan@kernel.org: clear PG_active on MADV_PAGEOUT]
Link: http://lkml.kernel.org/r/20190802200643.GA181880@google.com
[akpm@linux-foundation.org: resolve conflicts with hmm.git]
Link: http://lkml.kernel.org/r/20190726023435.214162-5-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: kbuild test robot <lkp@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Colascione <dancol@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Oleksandr Natalenko <oleksandr@redhat.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Sonny Rao <sonnyrao@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tim Murray <timmurray@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "Introduce MADV_COLD and MADV_PAGEOUT", v7.
- Background
The Android terminology used for forking a new process and starting an app
from scratch is a cold start, while resuming an existing app is a hot
start. While we continually try to improve the performance of cold
starts, hot starts will always be significantly less power hungry as well
as faster so we are trying to make hot start more likely than cold start.
To increase hot start, Android userspace manages the order that apps
should be killed in a process called ActivityManagerService.
ActivityManagerService tracks every Android app or service that the user
could be interacting with at any time and translates that into a ranked
list for lmkd(low memory killer daemon). They are likely to be killed by
lmkd if the system has to reclaim memory. In that sense they are similar
to entries in any other cache. Those apps are kept alive for
opportunistic performance improvements but those performance improvements
will vary based on the memory requirements of individual workloads.
- Problem
Naturally, cached apps were dominant consumers of memory on the system.
However, they were not significant consumers of swap even though they are
good candidate for swap. Under investigation, swapping out only begins
once the low zone watermark is hit and kswapd wakes up, but the overall
allocation rate in the system might trip lmkd thresholds and cause a
cached process to be killed(we measured performance swapping out vs.
zapping the memory by killing a process. Unsurprisingly, zapping is 10x
times faster even though we use zram which is much faster than real
storage) so kill from lmkd will often satisfy the high zone watermark,
resulting in very few pages actually being moved to swap.
- Approach
The approach we chose was to use a new interface to allow userspace to
proactively reclaim entire processes by leveraging platform information.
This allowed us to bypass the inaccuracy of the kernel’s LRUs for pages
that are known to be cold from userspace and to avoid races with lmkd by
reclaiming apps as soon as they entered the cached state. Additionally,
it could provide many chances for platform to use much information to
optimize memory efficiency.
To achieve the goal, the patchset introduce two new options for madvise.
One is MADV_COLD which will deactivate activated pages and the other is
MADV_PAGEOUT which will reclaim private pages instantly. These new
options complement MADV_DONTNEED and MADV_FREE by adding non-destructive
ways to gain some free memory space. MADV_PAGEOUT is similar to
MADV_DONTNEED in a way that it hints the kernel that memory region is not
currently needed and should be reclaimed immediately; MADV_COLD is similar
to MADV_FREE in a way that it hints the kernel that memory region is not
currently needed and should be reclaimed when memory pressure rises.
This patch (of 5):
When a process expects no accesses to a certain memory range, it could
give a hint to kernel that the pages can be reclaimed when memory pressure
happens but data should be preserved for future use. This could reduce
workingset eviction so it ends up increasing performance.
This patch introduces the new MADV_COLD hint to madvise(2) syscall.
MADV_COLD can be used by a process to mark a memory range as not expected
to be used in the near future. The hint can help kernel in deciding which
pages to evict early during memory pressure.
It works for every LRU pages like MADV_[DONTNEED|FREE]. IOW, It moves
active file page -> inactive file LRU
active anon page -> inacdtive anon LRU
Unlike MADV_FREE, it doesn't move active anonymous pages to inactive file
LRU's head because MADV_COLD is a little bit different symantic.
MADV_FREE means it's okay to discard when the memory pressure because the
content of the page is *garbage* so freeing such pages is almost zero
overhead since we don't need to swap out and access afterward causes just
minor fault. Thus, it would make sense to put those freeable pages in
inactive file LRU to compete other used-once pages. It makes sense for
implmentaion point of view, too because it's not swapbacked memory any
longer until it would be re-dirtied. Even, it could give a bonus to make
them be reclaimed on swapless system. However, MADV_COLD doesn't mean
garbage so reclaiming them requires swap-out/in in the end so it's bigger
cost. Since we have designed VM LRU aging based on cost-model, anonymous
cold pages would be better to position inactive anon's LRU list, not file
LRU. Furthermore, it would help to avoid unnecessary scanning if system
doesn't have a swap device. Let's start simpler way without adding
complexity at this moment. However, keep in mind, too that it's a caveat
that workloads with a lot of pages cache are likely to ignore MADV_COLD on
anonymous memory because we rarely age anonymous LRU lists.
* man-page material
MADV_COLD (since Linux x.x)
Pages in the specified regions will be treated as less-recently-accessed
compared to pages in the system with similar access frequencies. In
contrast to MADV_FREE, the contents of the region are preserved regardless
of subsequent writes to pages.
MADV_COLD cannot be applied to locked pages, Huge TLB pages, or VM_PFNMAP
pages.
[akpm@linux-foundation.org: resolve conflicts with hmm.git]
Link: http://lkml.kernel.org/r/20190726023435.214162-2-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reported-by: kbuild test robot <lkp@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Chris Zankel <chris@zankel.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Daniel Colascione <dancol@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Oleksandr Natalenko <oleksandr@redhat.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Sonny Rao <sonnyrao@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Tim Murray <timmurray@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull fuse updates from Miklos Szeredi:
- Continue separating the transport (user/kernel communication) and the
filesystem layers of fuse. Getting rid of most layering violations
will allow for easier cleanup and optimization later on.
- Prepare for the addition of the virtio-fs filesystem. The actual
filesystem will be introduced by a separate pull request.
- Convert to new mount API.
- Various fixes, optimizations and cleanups.
* tag 'fuse-update-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: (55 commits)
fuse: Make fuse_args_to_req static
fuse: fix memleak in cuse_channel_open
fuse: fix beyond-end-of-page access in fuse_parse_cache()
fuse: unexport fuse_put_request
fuse: kmemcg account fs data
fuse: on 64-bit store time in d_fsdata directly
fuse: fix missing unlock_page in fuse_writepage()
fuse: reserve byteswapped init opcodes
fuse: allow skipping control interface and forced unmount
fuse: dissociate DESTROY from fuseblk
fuse: delete dentry if timeout is zero
fuse: separate fuse device allocation and installation in fuse_conn
fuse: add fuse_iqueue_ops callbacks
fuse: extract fuse_fill_super_common()
fuse: export fuse_dequeue_forget() function
fuse: export fuse_get_unique()
fuse: export fuse_send_init_request()
fuse: export fuse_len_args()
fuse: export fuse_end_request()
fuse: fix request limit
...
