Chuck Lever [Wed, 24 Apr 2019 13:40:36 +0000 (09:40 -0400)]
xprtrdma: Update comments that reference ib_drain_qp
Commit e1ede312f17e ("xprtrdma: Fix helper that drains the
transport") replaced the ib_drain_qp() call, so update documenting
comments to reflect current operation.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Chuck Lever [Wed, 24 Apr 2019 13:40:20 +0000 (09:40 -0400)]
xprtrdma: Aggregate the inline settings in struct rpcrdma_ep
Clean up.
The inline settings are actually a characteristic of the endpoint,
and not related to the device. They are also modified after the
transport instance is created, so they do not belong in the cdata
structure either.
Lastly, let's use names that are more natural to RDMA than to NFS:
inline_write -> inline_send and inline_read -> inline_recv. The
/proc files retain their names to avoid breaking user space.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Chuck Lever [Wed, 24 Apr 2019 13:40:15 +0000 (09:40 -0400)]
xprtrdma: Remove rpcrdma_create_data_internal::rsize and wsize
Clean up.
xprt_rdma_max_inline_{read,write} cannot be set to large values
by virtue of proc_dointvec_minmax. The current maximum is
RPCRDMA_MAX_INLINE, which is much smaller than RPCRDMA_MAX_SEGS *
PAGE_SIZE.
The .rsize and .wsize fields are otherwise unused in the current
code base, and thus can be removed.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Chuck Lever [Wed, 24 Apr 2019 13:40:04 +0000 (09:40 -0400)]
xprtrdma: Eliminate rpcrdma_ia::ri_device
Clean up.
Since commit 54cbd6b0c6b9 ("xprtrdma: Delay DMA mapping Send and
Receive buffers"), a pointer to the device is now saved in each
regbuf when it is DMA mapped.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Chuck Lever [Wed, 24 Apr 2019 13:39:53 +0000 (09:39 -0400)]
xprtrdma: Clean up sendctx functions
Minor clean-ups I've stumbled on since sendctx was merged last year.
In particular, making Send completion processing more efficient
appears to have a measurable impact on IOPS throughput.
Note: test_and_clear_bit() returns a value, thus an explicit memory
barrier is not necessary.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Chuck Lever [Wed, 24 Apr 2019 13:39:21 +0000 (09:39 -0400)]
xprtrdma: Allocate req's regbufs at xprt create time
Allocating an rpcrdma_req's regbufs at xprt create time enables
a pair of micro-optimizations:
First, if these regbufs are always there, we can eliminate two
conditional branches from the hot xprt_rdma_allocate path.
Second, by allocating a 1KB buffer, it places a lower bound on the
size of these buffers, without adding yet another conditional
branch. The lower bound reduces the number of hardway re-
allocations. In fact, for some workloads it completely eliminates
hardway allocations.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Chuck Lever [Wed, 24 Apr 2019 13:39:16 +0000 (09:39 -0400)]
xprtrdma: rpcrdma_regbuf alignment
Allocate the struct rpcrdma_regbuf separately from the I/O buffer
to better guarantee the alignment of the I/O buffer and eliminate
the wasted space between the rpcrdma_regbuf metadata and the buffer
itself.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Chuck Lever [Wed, 24 Apr 2019 13:39:05 +0000 (09:39 -0400)]
xprtrdma: Clean up rpcrdma_create_req()
Eventually, I'd like to invoke rpcrdma_create_req() during the
call_reserve step. Memory allocation there probably needs to use
GFP_NOIO. Therefore a set of GFP flags needs to be passed in.
As an additional clean up, just return a pointer or NULL, because
the only error return code here is -ENOMEM.
Lastly, clean up the function names to be consistent with the
pattern: "rpcrdma" _ object-type _ action
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Chuck Lever [Wed, 24 Apr 2019 13:39:00 +0000 (09:39 -0400)]
xprtrdma: Fix an frwr_map recovery nit
After a DMA map failure in frwr_map, mark the MR so that recycling
won't attempt to DMA unmap it.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Fixes: e2f34e26710b ("xprtrdma: Yet another double DMA-unmap") Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
NFS: Allow signal interruption of NFS4ERR_DELAYed operations
If the server is unable to immediately execute an RPC call, and returns
an NFS4ERR_DELAY then we can assume it is safe to interrupt the operation
in order to handle ordinary signals. This allows the application to
service timer interrupts that would otherwise have to wait until the
server is again able to respond.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
pNFS: Add tracking to limit the number of pNFS retries
When the client is reading or writing using pNFS, and hits an error
on the DS, then it typically sends a LAYOUTERROR and/or LAYOUTRETURN
to the MDS, before redirtying the failed pages, and going for a new
round of reads/writebacks. The problem is that if the server has no
way to fix the DS, then we may need a way to interrupt this loop
after a set number of attempts have been made.
This patch adds an optional module parameter that allows the admin
to specify how many times to retry the read/writeback process before
failing with a fatal error.
The default behaviour is to retry forever.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
vfs_fsync() has the side effect of clearing unreported writeback errors,
so we need to make sure that we do not abuse it in situations where
applications might not normally expect us to report those errors.
The solution is to replace calls to vfs_fsync() with calls to nfs_wb_all().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
NFS: Don't call generic_error_remove_page() while holding locks
The NFS read code can trigger writeback while holding the page lock.
If an error then triggers a call to nfs_write_error_remove_page(),
we can deadlock.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
NFS: Don't interrupt file writeout due to fatal errors
When flushing out dirty pages, the fact that we may hit fatal errors
is not a reason to stop writeback. Those errors are reported through
fsync(), not through the flush mechanism.
Fixes: a6598813a4c5b ("NFS: Don't write back further requests if there...") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
NFS: Add a mount option "softerr" to allow clients to see ETIMEDOUT errors
Add a mount option that exposes the ETIMEDOUT errors that occur during
soft timeouts to the application. This allows aware applications to
distinguish between server disk IO errors and client timeout errors.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When we introduce the 'softerr' mount option, we will see the RPC
layer returning ETIMEDOUT errors if the server is unresponsive. We
want to consider those errors to be fatal on par with the EIO errors
that are returned by ordinary 'soft' timeouts..
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
SUNRPC: Start the first major timeout calculation at task creation
When calculating the major timeout for a new task, when we know that the
connection has been broken, use the task->tk_start to ensure that we also
take into account the time spent waiting for a slot or session slot. This
ensures that we fail over soft requests relatively quickly once the
connection has actually been broken, and the first requests have
started to fail.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
SUNRPC: Make "no retrans timeout" soft tasks behave like softconn for timeouts
If a soft NFSv4 request is sent, then we don't need it to time out unless
the connection breaks. The reason is that as long as the connection is
unbroken, the protocol states that the server is not allowed to drop the
request. IOW: as long as the connection remains unbroken, the client may
assume that all transmitted RPC requests are being processed by the server,
and that retransmissions and timeouts of those requests are unwarranted.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Add variables to track RPC level errors so that we can distinguish
between issue that arose in the RPC transport layer as opposed to
those arising from the reply message.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up the RPC task sleep interfaces by replacing the task->tk_timeout
'hidden parameter' to rpc_sleep_on() with a new function that takes an
absolute timeout.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
rpc_sleep_on() does not need to set the task->tk_callback under the
queue lock, so move that out.
Also refactor the check for whether the task is active.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Convert the transport callback to actually put the request to sleep
instead of just setting a timeout. This is in preparation for
rpc_sleep_on_timeout().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The RPC_TASK_KILLED flag should really not be set from another context
because it can clobber data in the struct task when task->tk_flags is
changed non-atomically.
Let's therefore swap out RPC_TASK_KILLED with an atomic flag, and add
a function to set that flag and safely wake up the task.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Merge tag 'nfs-for-5.1-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfix from Trond Myklebust:
"Fix a regression in which an RPC call can be tagged with an error
despite the transmission being successful"
* tag 'nfs-for-5.1-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
SUNRPC: Ignore queue transmission errors on successful transmission
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Three minor fixes: two obvious ones in drivers and a fix to the SG_IO
path to correctly return status on error"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: aic7xxx: fix EISA support
Revert "scsi: fcoe: clear FC_RP_STARTED flags when receiving a LOGO"
scsi: core: set result when the command cannot be dispatched
Merge tag 'for-linus-20190420' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"A set of small fixes that should go into this series. This contains:
- Removal of unused queue member (Hou)
- Overflow bvec fix (Ming)
- Various little io_uring tweaks (me)
- kthread parking
- Only call cpu_possible() for verified CPU
- Drop unused 'file' argument to io_file_put()
- io_uring_enter vs io_uring_register deadlock fix
- CQ overflow fix
- BFQ internal depth update fix (me)"
* tag 'for-linus-20190420' of git://git.kernel.dk/linux-block:
block: make sure that bvec length can't be overflow
block: kill all_q_node in request_queue
io_uring: fix CQ overflow condition
io_uring: fix possible deadlock between io_uring_{enter,register}
io_uring: drop io_file_put() 'file' argument
bfq: update internal depth state when queue depth changes
io_uring: only test SQPOLL cpu after we've verified it
io_uring: park SQPOLL thread if it's percpu
Merge tag 'i3c/fixes-for-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux
Pill i3c fixes from Boris Brezillon:
- fix the random PID check
- fix the disable controller logic in the designware driver
- fix I3C entry in MAINTAINERS
* tag 'i3c/fixes-for-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux:
MAINTAINERS: Fix the I3C entry
i3c: dw: Fix dw_i3c_master_disable controller by using correct mask
i3c: Fix the verification of random PID
Merge tag 'sound-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"Two core fixes for long-standing bugs for the races at concurrent
device creation and deletion that were (unsurprisingly) spotted by
syzkaller with usb-fuzzer.
The rest are usual small HD-audio fixes"
* tag 'sound-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: hda/realtek - add two more pin configuration sets to quirk table
ALSA: core: Fix card races between register and disconnect
ALSA: info: Fix racy addition/deletion of nodes
ALSA: hda: Initialize power_state field properly
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"Misc fixes:
- various tooling fixes
- kretprobe fixes
- kprobes annotation fixes
- kprobes error checking fix
- fix the default events for AMD Family 17h CPUs
- PEBS fix
- AUX record fix
- address filtering fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/kprobes: Avoid kretprobe recursion bug
kprobes: Mark ftrace mcount handler functions nokprobe
x86/kprobes: Verify stack frame on kretprobe
perf/x86/amd: Add event map for AMD Family 17h
perf bpf: Return NULL when RB tree lookup fails in perf_env__find_btf()
perf tools: Fix map reference counting
perf evlist: Fix side band thread draining
perf tools: Check maps for bpf programs
perf bpf: Return NULL when RB tree lookup fails in perf_env__find_bpf_prog_info()
tools include uapi: Sync sound/asound.h copy
perf top: Always sample time to satisfy needs of use of ordered queuing
perf evsel: Use hweight64() instead of hweight_long(attr.sample_regs_user)
tools lib traceevent: Fix missing equality check for strcmp
perf stat: Disable DIR_FORMAT feature for 'perf stat record'
perf scripts python: export-to-sqlite.py: Fix use of parent_id in calls_view
perf header: Fix lock/unlock imbalances when processing BPF/BTF info
perf/x86: Fix incorrect PEBS_REGS
perf/ring_buffer: Fix AUX record suppression
perf/core: Fix the address filtering fix
kprobes: Fix error check when reusing optimized probes
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
"Misc fixes all over the place: a console spam fix, section attributes
fixes, a KASLR fix, a TLB stack-variable alignment fix, a reboot
quirk, boot options related warnings fix, an LTO fix, a deadlock fix
and an RDT fix"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu/intel: Lower the "ENERGY_PERF_BIAS: Set to normal" message's log priority
x86/cpu/bugs: Use __initconst for 'const' init data
x86/mm/KASLR: Fix the size of the direct mapping section
x86/Kconfig: Fix spelling mistake "effectivness" -> "effectiveness"
x86/mm/tlb: Revert "x86/mm: Align TLB invalidation info"
x86/reboot, efi: Use EFI reboot for Acer TravelMate X514-51T
x86/mm: Prevent bogus warnings with "noexec=off"
x86/build/lto: Fix truncated .bss with -fdata-sections
x86/speculation: Prevent deadlock on ssb_state::lock
x86/resctrl: Do not repeat rdtgroup mode initialization
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
"A deadline scheduler warning/race fix, and a cfs_period_us quota
calculation workaround where the real fix looks too involved to merge
immediately"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/deadline: Correctly handle active 0-lag timers
sched/fair: Limit sched_cfs_period_timer() loop to avoid hard lockup
Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
"A lockdep warning fix and a script execution fix when atomics are
generated"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/atomics: Don't assume that scripts are executable
locking/lockdep: Make lockdep_unregister_key() honor 'debug_locks' again
Merge tag 'tty-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial fixes from Greg KH:
"Here are five small fixes for some tty/serial/vt issues that have been
reported.
The vt one has been around for a while, it is good to finally get that
resolved. The others fix a build warning that showed up in 5.1-rc1,
and resolve a problem in the sh-sci driver.
Note, the second patch for build warning fix for the sc16is7xx driver
was just applied to the tree, as it resolves a problem with the
previous patch to try to solve the issue. It has not shown up in
linux-next yet, unlike all of the other patches, but it has passed
0-day testing and everyone seems to agree that it is correct"
* tag 'tty-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
sc16is7xx: put err_spi and err_i2c into correct #ifdef
vt: fix cursor when clearing the screen
sc16is7xx: move label 'err_spi' to correct section
serial: sh-sci: Fix HSCIF RX sampling point adjustment
serial: sh-sci: Fix HSCIF RX sampling point calculation
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping
mm/kmemleak.c: fix unused-function warning
init: initialize jump labels before command line option parsing
kernel/watchdog_hld.c: hard lockup message should end with a newline
kcov: improve CONFIG_ARCH_HAS_KCOV help text
mm: fix inactive list balancing between NUMA nodes and cgroups
mm/hotplug: treat CMA pages as unmovable
proc: fixup proc-pid-vm test
proc: fix map_files test on F29
mm/vmstat.c: fix /proc/vmstat format for CONFIG_DEBUG_TLBFLUSH=y CONFIG_SMP=n
mm/memory_hotplug: do not unlock after failing to take the device_hotplug_lock
mm: swapoff: shmem_unuse() stop eviction without igrab()
mm: swapoff: take notice of completion sooner
mm: swapoff: remove too limiting SWAP_UNUSE_MAX_TRIES
mm: swapoff: shmem_find_swap_entries() filter out other types
slab: store tagged freelist for off-slab slabmgmt
Merge tag 'staging-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging and IIO fixes from Greg KH:
"Here is a bunch of IIO driver fixes, and some smaller staging driver
fixes, for 5.1-rc6. The IIO fixes were delayed due to my vacation, but
all resolve a number of reported issues and have been in linux-next
for a few weeks with no reported issues.
The other staging driver fixes are all tiny, resolving some reported
issues in the comedi and most drivers, as well as some erofs fixes.
All of these patches have been in linux-next with no reported issues"
* tag 'staging-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (24 commits)
staging: comedi: ni_usb6501: Fix possible double-free of ->usb_rx_buf
staging: comedi: ni_usb6501: Fix use of uninitialized mutex
staging: erofs: fix unexpected out-of-bound data access
staging: comedi: vmk80xx: Fix possible double-free of ->usb_rx_buf
staging: comedi: vmk80xx: Fix use of uninitialized semaphore
staging: most: core: use device description as name
iio: core: fix a possible circular locking dependency
iio: ad_sigma_delta: select channel when reading register
iio: pms7003: select IIO_TRIGGERED_BUFFER
iio: cros_ec: Fix the maths for gyro scale calculation
iio: adc: xilinx: prevent touching unclocked h/w on remove
iio: adc: xilinx: fix potential use-after-free on probe
iio: adc: xilinx: fix potential use-after-free on remove
iio: dac: mcp4725: add missing powerdown bits in store eeprom
io: accel: kxcjk1013: restore the range after resume.
iio:chemical:bme680: Fix SPI read interface
iio:chemical:bme680: Fix, report temperature in millidegrees
iio: chemical: fix missing Kconfig block for sgp30
iio: adc: at91: disable adc channel interrupt in timeout case
iio: gyro: mpu3050: fix chip ID reading
...
Ming Lei [Wed, 17 Apr 2019 01:11:26 +0000 (09:11 +0800)]
block: make sure that bvec length can't be overflow
bvec->bv_offset may be bigger than PAGE_SIZE sometimes, such as,
when one bio is splitted in the middle of one bvec via bio_split(),
and bi_iter.bi_bvec_done is used to build offset of the 1st bvec of
remained bio. And the remained bio's bvec may be re-submitted to fs
layer via ITER_IBVEC, such as loop and nvme-loop.
So we have to make sure that every bvec's offset is less than
PAGE_SIZE from bio_for_each_segment_all() because some drivers(loop,
nvme-loop) passes the splitted bvec to fs layer via ITER_BVEC.
This patch fixes this issue reported by Zhang Yi When running nvme/011.
Cc: Christoph Hellwig <hch@lst.de> Cc: Yi Zhang <yi.zhang@redhat.com> Reported-by: Yi Zhang <yi.zhang@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Fixes: 6dc4f100c175 ("block: allow bio_for_each_segment_all() to iterate over multi-page bvec") Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull input updates from Dmitry Torokhov:
- several new key mappings for HID
- a host of new ACPI IDs used to identify Elan touchpads in Lenovo
laptops
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: snvs_pwrkey - initialize necessary driver data before enabling IRQ
HID: input: add mapping for "Toggle Display" key
HID: input: add mapping for "Full Screen" key
HID: input: add mapping for keyboard Brightness Up/Down/Toggle keys
HID: input: add mapping for Expose/Overview key
HID: input: fix mapping of aspect ratio key
[media] doc-rst: switch to new names for Full Screen/Aspect keys
Input: document meanings of KEY_SCREEN and KEY_ZOOM
Input: elan_i2c - add hardware ID for multiple Lenovo laptops
Hans de Goede [Sun, 30 Dec 2018 17:27:15 +0000 (18:27 +0100)]
x86/cpu/intel: Lower the "ENERGY_PERF_BIAS: Set to normal" message's log priority
The "ENERGY_PERF_BIAS: Set to 'normal', was 'performance'" message triggers
on pretty much every Intel machine. The purpose of log messages with
a warning level is to notify the user of something which potentially is
a problem, or at least somewhat unexpected.
This message clearly does not match those criteria, so lower its log
priority from warning to info.
Signed-off-by: Hans de Goede <hdegoede@redhat.com> Cc: Borislav Petkov <bp@alien8.de> 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/20181230172715.17469-1-hdegoede@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Merge tag 'perf-urgent-for-mingo-5.1-20190419' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
perf top:
Jiri Olsa:
- Fix 'perf top --pid', it needs PERF_SAMPLE_TIME since we switched to using
a different thread to sort the events and then even for just a single
thread we now need timestamps.
BPF:
Jiri Olsa:
- Fix bpf_prog and btf lookup functions failure path to to properly return
NULL.
- Fix side band thread draining, used to process PERF_RECORD_BPF_EVENT
metadata records.
core:
Jiri Olsa:
- Fix map lookup by name to get a refcount when the name is already in
the tree. Found
Song Liu:
- Fix __map__is_kmodule() by taking into account recently added BPF
maps.
UAPI:
Arnaldo Carvalho de Melo:
- Sync sound/asound.h copy
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andrea Arcangeli [Fri, 19 Apr 2019 00:50:52 +0000 (17:50 -0700)]
coredump: fix race condition between mmget_not_zero()/get_task_mm() and core dumping
The core dumping code has always run without holding the mmap_sem for
writing, despite that is the only way to ensure that the entire vma
layout will not change from under it. Only using some signal
serialization on the processes belonging to the mm is not nearly enough.
This was pointed out earlier. For example in Hugh's post from Jul 2017:
"Not strictly relevant here, but a related note: I was very surprised
to discover, only quite recently, how handle_mm_fault() may be called
without down_read(mmap_sem) - when core dumping. That seems a
misguided optimization to me, which would also be nice to correct"
In particular because the growsdown and growsup can move the
vm_start/vm_end the various loops the core dump does around the vma will
not be consistent if page faults can happen concurrently.
Pretty much all users calling mmget_not_zero()/get_task_mm() and then
taking the mmap_sem had the potential to introduce unexpected side
effects in the core dumping code.
Adding mmap_sem for writing around the ->core_dump invocation is a
viable long term fix, but it requires removing all copy user and page
faults and to replace them with get_dump_page() for all binary formats
which is not suitable as a short term fix.
For the time being this solution manually covers the places that can
confuse the core dump either by altering the vma layout or the vma flags
while it runs. Once ->core_dump runs under mmap_sem for writing the
function mmget_still_valid() can be dropped.
Allowing mmap_sem protected sections to run in parallel with the
coredump provides some minor parallelism advantage to the swapoff code
(which seems to be safe enough by never mangling any vma field and can
keep doing swapins in parallel to the core dumping) and to some other
corner case.
In order to facilitate the backporting I added "Fixes: 86039bd3b4e6"
however the side effect of this same race condition in /proc/pid/mem
should be reproducible since before 2.6.12-rc2 so I couldn't add any
other "Fixes:" because there's no hash beyond the git genesis commit.
Because find_extend_vma() is the only location outside of the process
context that could modify the "mm" structures under mmap_sem for
reading, by adding the mmget_still_valid() check to it, all other cases
that take the mmap_sem for reading don't need the new check after
mmget_not_zero()/get_task_mm(). The expand_stack() in page fault
context also doesn't need the new check, because all tasks under core
dumping are frozen.
Link: http://lkml.kernel.org/r/20190325224949.11068-1-aarcange@redhat.com Fixes: 86039bd3b4e6 ("userfaultfd: add new syscall to provide memory externalization") Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Reported-by: Jann Horn <jannh@google.com> Suggested-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Xu <peterx@redhat.com> Reviewed-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Jann Horn <jannh@google.com> Acked-by: Jason Gunthorpe <jgg@mellanox.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dan Williams [Fri, 19 Apr 2019 00:50:44 +0000 (17:50 -0700)]
init: initialize jump labels before command line option parsing
When a module option, or core kernel argument, toggles a static-key it
requires jump labels to be initialized early. While x86, PowerPC, and
ARM64 arrange for jump_label_init() to be called before parse_args(),
ARM does not.
Kernel command line: rdinit=/sbin/init page_alloc.shuffle=1 panic=-1 console=ttyAMA0,115200 page_alloc.shuffle=1
------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at ./include/linux/jump_label.h:303
page_alloc_shuffle+0x12c/0x1ac
static_key_enable(): static key 'page_alloc_shuffle_key+0x0/0x4' used
before call to jump_label_init()
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 5.1.0-rc4-next-20190410-00003-g3367c36ce744 #1
Hardware name: ARM Integrator/CP (Device Tree)
[<c0011c68>] (unwind_backtrace) from [<c000ec48>] (show_stack+0x10/0x18)
[<c000ec48>] (show_stack) from [<c07e9710>] (dump_stack+0x18/0x24)
[<c07e9710>] (dump_stack) from [<c001bb1c>] (__warn+0xe0/0x108)
[<c001bb1c>] (__warn) from [<c001bb88>] (warn_slowpath_fmt+0x44/0x6c)
[<c001bb88>] (warn_slowpath_fmt) from [<c0b0c4a8>]
(page_alloc_shuffle+0x12c/0x1ac)
[<c0b0c4a8>] (page_alloc_shuffle) from [<c0b0c550>] (shuffle_store+0x28/0x48)
[<c0b0c550>] (shuffle_store) from [<c003e6a0>] (parse_args+0x1f4/0x350)
[<c003e6a0>] (parse_args) from [<c0ac3c00>] (start_kernel+0x1c0/0x488)
Move the fallback call to jump_label_init() to occur before
parse_args().
The redundant calls to jump_label_init() in other archs are left intact
in case they have static key toggling use cases that are even earlier
than option parsing.
Link: http://lkml.kernel.org/r/155544804466.1032396.13418949511615676665.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reported-by: Guenter Roeck <groeck@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Russell King <rmk@armlinux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mark Rutland [Fri, 19 Apr 2019 00:50:37 +0000 (17:50 -0700)]
kcov: improve CONFIG_ARCH_HAS_KCOV help text
The help text for CONFIG_ARCH_HAS_KCOV is stale, and describes the
feature as being enabled only for x86_64, when it is now enabled for
several architectures, including arm, arm64, powerpc, and s390.
Let's remove that stale help text, and update it along the lines of hat
for ARCH_HAS_FORTIFY_SOURCE, better describing when an architecture
should select CONFIG_ARCH_HAS_KCOV.
Johannes Weiner [Fri, 19 Apr 2019 00:50:34 +0000 (17:50 -0700)]
mm: fix inactive list balancing between NUMA nodes and cgroups
During !CONFIG_CGROUP reclaim, we expand the inactive list size if it's
thrashing on the node that is about to be reclaimed. But when cgroups
are enabled, we suddenly ignore the node scope and use the cgroup scope
only. The result is that pressure bleeds between NUMA nodes depending
on whether cgroups are merely compiled into Linux. This behavioral
difference is unexpected and undesirable.
When the refault adaptivity of the inactive list was first introduced,
there were no statistics at the lruvec level - the intersection of node
and memcg - so it was better than nothing.
But now that we have that infrastructure, use lruvec_page_state() to
make the list balancing decision always NUMA aware.
[hannes@cmpxchg.org: fix bisection hole] Link: http://lkml.kernel.org/r/20190417155241.GB23013@cmpxchg.org Link: http://lkml.kernel.org/r/20190412144438.2645-1-hannes@cmpxchg.org Fixes: 2a2e48854d70 ("mm: vmscan: fix IO/refault regression in cache workingset transition") Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Cc: Roman Gushchin <guro@fb.com> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Qian Cai [Fri, 19 Apr 2019 00:50:30 +0000 (17:50 -0700)]
mm/hotplug: treat CMA pages as unmovable
has_unmovable_pages() is used by allocating CMA and gigantic pages as
well as the memory hotplug. The later doesn't know how to offline CMA
pool properly now, but if an unused (free) CMA page is encountered, then
has_unmovable_pages() happily considers it as a free memory and
propagates this up the call chain. Memory offlining code then frees the
page without a proper CMA tear down which leads to an accounting issues.
Moreover if the same memory range is onlined again then the memory never
gets back to the CMA pool.
Also, kmemleak still think those memory address are reserved below but
have already been used by the buddy allocator after onlining. This
patch fixes the situation by treating CMA pageblocks as unmovable except
when has_unmovable_pages() is called as part of CMA allocation.
[cai@lca.pw: use is_migrate_cma_page() and update commit log] Link: http://lkml.kernel.org/r/20190416170510.20048-1-cai@lca.pw Link: http://lkml.kernel.org/r/20190413002623.8967-1-cai@lca.pw Signed-off-by: Qian Cai <cai@lca.pw> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Oscar Salvador <osalvador@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/vmstat.c: fix /proc/vmstat format for CONFIG_DEBUG_TLBFLUSH=y CONFIG_SMP=n
Commit 58bc4c34d249 ("mm/vmstat.c: skip NR_TLB_REMOTE_FLUSH* properly")
depends on skipping vmstat entries with empty name introduced in 7aaf77272358 ("mm: don't show nr_indirectly_reclaimable in
/proc/vmstat") but reverted in b29940c1abd7 ("mm: rename and change
semantics of nr_indirectly_reclaimable_bytes").
So skipping no longer works and /proc/vmstat has misformatted lines " 0".
This patch simply shows debug counters "nr_tlb_remote_*" for UP.
mm/memory_hotplug: do not unlock after failing to take the device_hotplug_lock
When adding memory by probing a memory block in the sysfs interface,
there is an obvious issue where we will unlock the device_hotplug_lock
when we failed to takes it.
That issue was introduced in 8df1d0e4a265 ("mm/memory_hotplug: make
add_memory() take the device_hotplug_lock").
We should drop out in time when failing to take the device_hotplug_lock.
Link: http://lkml.kernel.org/r/1554696437-9593-1-git-send-email-zhongjiang@huawei.com Fixes: 8df1d0e4a265 ("mm/memory_hotplug: make add_memory() take the device_hotplug_lock") Signed-off-by: zhong jiang <zhongjiang@huawei.com> Reported-by: Yang yingliang <yangyingliang@huawei.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm: swapoff: shmem_unuse() stop eviction without igrab()
The igrab() in shmem_unuse() looks good, but we forgot that it gives no
protection against concurrent unmounting: a point made by Konstantin
Khlebnikov eight years ago, and then fixed in 2.6.39 by 778dd893ae78
("tmpfs: fix race between umount and swapoff"). The current 5.1-rc
swapoff is liable to hit "VFS: Busy inodes after unmount of tmpfs.
Self-destruct in 5 seconds. Have a nice day..." followed by GPF.
Once again, give up on using igrab(); but don't go back to making such
heavy-handed use of shmem_swaplist_mutex as last time: that would spoil
the new design, and I expect could deadlock inside shmem_swapin_page().
Instead, shmem_unuse() just raise a "stop_eviction" count in the shmem-
specific inode, and shmem_evict_inode() wait for that to go down to 0.
Call it "stop_eviction" rather than "swapoff_busy" because it can be put
to use for others later (huge tmpfs patches expect to use it).
That simplifies shmem_unuse(), protecting it from both unlink and
unmount; and in practice lets it locate all the swap in its first try.
But do not rely on that: there's still a theoretical case, when
shmem_writepage() might have been preempted after its get_swap_page(),
before making the swap entry visible to swapoff.
mm: swapoff: remove too limiting SWAP_UNUSE_MAX_TRIES
SWAP_UNUSE_MAX_TRIES 3 appeared to work well in earlier testing, but
further testing has proved it to be a source of unnecessary swapoff
EBUSY failures (which can then be followed by unmount EBUSY failures).
When mmget_not_zero() or shmem's igrab() fails, there is an mm exiting
or inode being evicted, freeing up swap independent of try_to_unuse().
Those typically completed much sooner than the old quadratic swapoff,
but now it's more common that swapoff may need to wait for them.
It's possible to move those cases from init_mm.mmlist and shmem_swaplist
to separate "exiting" swaplists, and try_to_unuse() then wait for those
lists to be emptied; but we've not bothered with that in the past, and
don't want to risk missing some other forgotten case. So just revert to
cycling around until the swap is gone, without any retries limit.
mm: swapoff: shmem_find_swap_entries() filter out other types
Swapfile "type" was passed all the way down to shmem_unuse_inode(), but
then forgotten from shmem_find_swap_entries(): with the result that
removing one swapfile would try to free up all the swap from shmem - no
problem when only one swapfile anyway, but counter-productive when more,
causing swapoff to be unnecessarily OOM-killed when it should succeed.
Qian Cai [Fri, 19 Apr 2019 00:49:55 +0000 (17:49 -0700)]
slab: store tagged freelist for off-slab slabmgmt
Commit 51dedad06b5f ("kasan, slab: make freelist stored without tags")
calls kasan_reset_tag() for off-slab slab management object leading to
freelist being stored non-tagged.
However, cache_grow_begin() calls alloc_slabmgmt() which calls
kmem_cache_alloc_node() assigns a tag for the address and stores it in
the shadow address. As the result, it causes endless errors below
during boot due to drain_freelist() -> slab_destroy() ->
kasan_slab_free() which compares already untagged freelist against the
stored tag in the shadow address.
Since off-slab slab management object freelist is such a special case,
just store it tagged. Non-off-slab management object freelist is still
stored untagged which has not been assigned a tag and should not cause
any other troubles with this inconsistency.
BUG: KASAN: double-free or invalid-free in slab_destroy+0x84/0x88
Pointer tag: [ff], memory tag: [99]
The buggy address belongs to the object at ffff809681b89e00
which belongs to the cache kmalloc-128 of size 128
The buggy address is located 0 bytes inside of
128-byte region [ffff809681b89e00, ffff809681b89e80)
The buggy address belongs to the page:
page:ffff7fe025a06e00 count:1 mapcount:0 mapping:01ff80082000fb00
index:0xffff809681b8fe04
flags: 0x17ffffffc000200(slab)
raw: 017ffffffc000200ffff7fe025a06d08ffff7fe022ef7b8801ff80082000fb00
raw: ffff809681b8fe04ffff809681b8000000000001000000e00000000000000000
page dumped because: kasan: bad access detected
page allocated via order 0, migratetype Unmovable, gfp_mask
0x2420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE)
prep_new_page+0x4e0/0x5e0
get_page_from_freelist+0x4ce8/0x50d4
__alloc_pages_nodemask+0x738/0x38b8
cache_grow_begin+0xd8/0xa24
____cache_alloc_node+0x14c/0x268
__kmalloc+0x1c8/0x3fc
ftrace_free_mem+0x408/0x1284
ftrace_free_init_mem+0x20/0x28
kernel_init+0x24/0x548
ret_from_fork+0x10/0x18
Memory state around the buggy address: ffff809681b89c00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe ffff809681b89d00: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
>ffff809681b89e00: 99 99 99 99 99 99 99 99 fe fe fe fe fe fe fe fe
^ ffff809681b89f00: 43 43 43 43 43 fe fe fe fe fe fe fe fe fe fe fe ffff809681b8a000: 6d fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
Link: http://lkml.kernel.org/r/20190403022858.97584-1-cai@lca.pw Fixes: 51dedad06b5f ("kasan, slab: make freelist stored without tags") Signed-off-by: Qian Cai <cai@lca.pw> Reviewed-by: Andrey Konovalov <andreyknvl@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Masami Hiramatsu [Sat, 23 Feb 2019 16:50:49 +0000 (01:50 +0900)]
x86/kprobes: Avoid kretprobe recursion bug
Avoid kretprobe recursion loop bg by setting a dummy
kprobes to current_kprobe per-CPU variable.
This bug has been introduced with the asm-coded trampoline
code, since previously it used another kprobe for hooking
the function return placeholder (which only has a nop) and
trampoline handler was called from that kprobe.
This revives the old lost kprobe again.
With this fix, we don't see deadlock anymore.
And you can see that all inner-called kretprobe are skipped.
event_1 235 0
event_2 19375 19612
The 1st column is recorded count and the 2nd is missed count.
Above shows (event_1 rec) + (event_2 rec) ~= (event_2 missed)
(some difference are here because the counter is racy)
Reported-by: Andrea Righi <righi.andrea@gmail.com> Tested-by: Andrea Righi <righi.andrea@gmail.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Fixes: c9becf58d935 ("[PATCH] kretprobe: kretprobe-booster") Link: http://lkml.kernel.org/r/155094064889.6137.972160690963039.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
Masami Hiramatsu [Sat, 23 Feb 2019 16:50:20 +0000 (01:50 +0900)]
kprobes: Mark ftrace mcount handler functions nokprobe
Mark ftrace mcount handler functions nokprobe since
probing on these functions with kretprobe pushes
return address incorrectly on kretprobe shadow stack.
Reported-by: Francis Deslauriers <francis.deslauriers@efficios.com> Tested-by: Andrea Righi <righi.andrea@gmail.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/155094062044.6137.6419622920568680640.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
Masami Hiramatsu [Sat, 23 Feb 2019 16:49:52 +0000 (01:49 +0900)]
x86/kprobes: Verify stack frame on kretprobe
Verify the stack frame pointer on kretprobe trampoline handler,
If the stack frame pointer does not match, it skips the wrong
entry and tries to find correct one.
This can happen if user puts the kretprobe on the function
which can be used in the path of ftrace user-function call.
Such functions should not be probed, so this adds a warning
message that reports which function should be blacklisted.
Tested-by: Andrea Righi <righi.andrea@gmail.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/155094059185.6137.15527904013362842072.stgit@devbox Signed-off-by: Ingo Molnar <mingo@kernel.org>
sc16is7xx: put err_spi and err_i2c into correct #ifdef
err_spi is only called within SERIAL_SC16IS7XX_SPI
while err_i2c is called inside SERIAL_SC16IS7XX_I2C.
So we need to put err_spi and err_i2c into each #ifdef
accordingly.
This change fixes ("sc16is7xx: move label 'err_spi'
to correct section").
Instead of relying on the now removed NULL argument to
pci_alloc_consistent, switch to the generic DMA API, and store the struct
device so that we can pass it.
Fixes: 4167b2ad5182 ("PCI: Remove NULL device handling from PCI DMA API") Reported-by: Matthew Whitehead <tedheadster@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Matthew Whitehead <tedheadster@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fix from Catalin Marinas:
"Avoid compiler uninitialised warning introduced by recent arm64 futex
fix"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: futex: Restore oldval initialization to work around buggy compilers
arm64: futex: Restore oldval initialization to work around buggy compilers
Commit 045afc24124d ("arm64: futex: Fix FUTEX_WAKE_OP atomic ops with
non-zero result value") removed oldval's zero initialization in
arch_futex_atomic_op_inuser because it is not necessary. Unfortunately,
Android's arm64 GCC 4.9.4 [1] does not agree:
../kernel/futex.c: In function 'do_futex':
../kernel/futex.c:1658:17: warning: 'oldval' may be used uninitialized
in this function [-Wmaybe-uninitialized]
return oldval == cmparg;
^
In file included from ../kernel/futex.c:73:0:
../arch/arm64/include/asm/futex.h:53:6: note: 'oldval' was declared here
int oldval, ret, tmp;
^
GCC fails to follow that when ret is non-zero, futex_atomic_op_inuser
returns right away, avoiding the uninitialized use that it claims.
Restoring the zero initialization works around this issue.
As stated in the original commit for pidfd_send_signal() we don't allow
to signal processes through O_PATH file descriptors since it is
semantically equivalent to a write on the pidfd.
We already correctly error out right now and return EBADF if an O_PATH
fd is passed. This is because we use file->f_op to detect whether a
pidfd is passed and O_PATH fds have their file->f_op set to empty_fops
in do_dentry_open() and thus fail the test.
Thus, there is no regression. It's just semantically correct to use
fdget() and return an error right from there instead of taking a
reference and returning an error later.
Signed-off-by: Christian Brauner <christian@brauner.io> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Kees Cook <keescook@chromium.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jann Horn <jann@thejh.net> Cc: David Howells <dhowells@redhat.com> Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com> Cc: Andy Lutomirsky <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>