Add a new option flag indicating whether or not the ring buffer is in
'absolute timestamp' mode.
Currently this is only set/unset by hist triggers that make use of a
common_timestamp. As such, there's no reason to make this writeable
for users - its purpose is only to allow users to determine
unequivocally whether or not the ring buffer is in that mode (although
absolute timestamps can coexist with the normal delta timestamps, when
the ring buffer is in absolute mode, timestamps written while absolute
mode is in effect take up more space in the buffer, and are not as
efficient).
Link: http://lkml.kernel.org/r/e8aa7b1cde1cf15014e66545d06ac6ef2ebba456.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
RINGBUF_TYPE_TIME_STAMP is defined but not used, and from what I can
gather was reserved for something like an absolute timestamp feature
for the ring buffer, if not a complete replacement of the current
time_delta scheme.
This code redefines RINGBUF_TYPE_TIME_STAMP to implement absolute time
stamps. Another way to look at it is that it essentially forces
extended time_deltas for all events.
The motivation for doing this is to enable time_deltas that aren't
dependent on previous events in the ring buffer, making it feasible to
use the ring_buffer_event timetamps in a more random-access way, for
purposes other than serial event printing.
To set/reset this mode, use tracing_set_timestamp_abs() from the
previous interface patch.
Link: http://lkml.kernel.org/r/477b362dba1ce7fab9889a1a8e885a62c472f041.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Define a new function, tracing_set_time_stamp_abs(), which can be used
to enable or disable the use of absolute timestamps rather than time
deltas for a trace array.
Only the interface is added here; a subsequent patch will add the
underlying implementation.
Link: http://lkml.kernel.org/r/ce96119de44c7fe0ee44786d15254e9b493040d3.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
We now have the logic to detect and remove duplicates in the
tracing_map hash table. The code which merges duplicates in the
histogram is redundant now. So, modify this code just to detect
duplicates. The duplication detection code is still kept to ensure
that any rare race condition which might cause duplicates does not go
unnoticed.
Link: http://lkml.kernel.org/r/55215cf59e2674391bdaf772fdafc4c393352b03.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
A duplicate in the tracing_map hash table is when 2 different entries
have the same key and, as a result, the key_hash. This is possible due
to a race condition in the algorithm. This race condition is inherent to
the algorithm and not a bug. This was fine because, until now, we were
only interested in the sum of all the values related to a particular
key (the duplicates are dealt with in tracing_map_sort_entries()). But,
with the inclusion of variables[1], we are interested in individual
values. So, it will not be clear what value to choose when
there are duplicates. So, the duplicates need to be removed.
The duplicates can occur in the code in the following scenarios:
- A thread is in the process of adding a new element. It has
successfully executed cmpxchg() and inserted the key. But, it is still
not done acquiring the trace_map_elt struct, populating it and storing
the pointer to the struct in the value field of tracing_map hash table.
If another thread comes in at this time and wants to add an element with
the same key, it will not see the current element and add a new one.
- There are multiple threads trying to execute cmpxchg at the same time,
one of the threads will succeed and the others will fail. The ones which
fail will go ahead increment 'idx' and add a new element there creating
a duplicate.
This patch detects and avoids the first condition by asking the thread
which detects the duplicate to loop one more time. There is also a
possibility of infinite loop if the thread which is trying to insert
goes to sleep indefinitely and the one which is trying to insert a new
element detects a duplicate. Which is why, the thread loops for
map_size iterations before returning NULL.
The second scenario is avoided by preventing the threads which failed
cmpxchg() from incrementing idx. This way, they will loop
around and check if the thread which succeeded in executing cmpxchg()
had the same key.
[1] http://lkml.kernel.org/r/cover.1498510759.git.tom.zanussi@linux.intel.com
Link: http://lkml.kernel.org/r/e178e89ec399240331d383bd5913d649713110f4.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull timer fixes from Thomas Gleixner:
"A small set of fixes from the timer departement:
- Add a missing timer wheel clock forward when migrating timers off a
unplugged CPU to prevent operating on a stale clock base and
missing timer deadlines.
- Use the proper shift count to extract data from a register value to
prevent evaluating unrelated bits
- Make the error return check in the FSL timer driver work correctly.
Checking an unsigned variable for less than zero does not really
work well.
- Clarify the confusing comments in the ARC timer code"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timers: Forward timer base before migrating timers
clocksource/drivers/arc_timer: Update some comments
clocksource/drivers/mips-gic-timer: Use correct shift count to extract data
clocksource/drivers/fsl_ftm_timer: Fix error return checking
Pull libnvdimm fixes from Dan Williams:
"A 4.16 regression fix, three fixes for -stable, and a cleanup fix:
- During the merge window support for the new ACPI NVDIMM Platform
Capabilities structure disabled support for "deep flush", a
force-unit- access like mechanism for persistent memory. Restore
that mechanism.
- VFIO like RDMA is yet one more memory registration / pinning
interface that is incompatible with Filesystem-DAX. Disable long
term pins of Filesystem-DAX mappings via VFIO.
- The Filesystem-DAX detection to prevent long terms pins mistakenly
also disabled Device-DAX pins which are not subject to the same
block- map collision concerns.
- Similar to the setup path, softlockup warnings can trigger in the
shutdown path for large persistent memory namespaces. Teach
for_each_device_pfn() to perform cond_resched() in all cases.
- Boaz noticed that the might_sleep() in dax_direct_access() is stale
as of the v4.15 kernel.
These have received a build success notification from the 0day robot,
and the longterm pin fixes have appeared in -next. However, I recently
rebased the tree to remove some other fixes that need to be reworked
after review feedback.
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
memremap: fix softlockup reports at teardown
libnvdimm: re-enable deep flush for pmem devices via fsync()
vfio: disable filesystem-dax page pinning
dax: fix vma_is_fsdax() helper
dax: ->direct_access does not sleep anymore
The cond_resched() currently in the setup path needs to be duplicated in
the teardown path. Rather than require each instance of
for_each_device_pfn() to open code the same sequence, embed it in the
helper.
Link: https://github.com/intel/ixpdimm_sw/issues/11
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <stable@vger.kernel.org>
Fixes: 7138970383 ("mm, zone_device: Replace {get, put}_zone_device_page()...")
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Pull printk fix from Petr Mladek:
"Make sure that we wake up userspace loggers. This fixes a race
introduced by the console waiter logic during this merge window"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
printk: Wake klogd when passing console_lock owner
On CPU hotunplug the enqueued timers of the unplugged CPU are migrated to a
live CPU. This happens from the control thread which initiated the unplug.
If the CPU on which the control thread runs came out from a longer idle
period then the base clock of that CPU might be stale because the control
thread runs prior to any event which forwards the clock.
In such a case the timers from the unplugged CPU are queued on the live CPU
based on the stale clock which can cause large delays due to increased
granularity of the outer timer wheels which are far away from base:;clock.
But there is a worse problem than that. The following sequence of events
illustrates it:
- CPU0 timer1 is queued expires = 59969 and base->clk = 59131.
The timer is queued at wheel level 2, with resulting expiry time = 60032
(due to level granularity).
- CPU1 enters idle @60007, with next timer expiry @60020.
- CPU0 is hotplugged at @60009
- CPU1 exits idle and runs the control thread which migrates the
timers from CPU0
timer1 is now queued in level 0 for immediate handling in the next
softirq because the requested expiry time 59969 is before CPU1 base->clk
60007
- CPU1 runs code which forwards the base clock which succeeds because the
next expiring timer. which was collected at idle entry time is still set
to 60020.
So it forwards beyond 60007 and therefore misses to expire the migrated
timer1. That timer gets expired when the wheel wraps around again, which
takes between 63 and 630ms depending on the HZ setting.
Address both problems by invoking forward_timer_base() for the control CPUs
timer base. All other places, which might run into a similar problem
(mod_timer()/add_timer_on()) already invoke forward_timer_base() to avoid
that.
[ tglx: Massaged comment and changelog ]
Fixes: a683f390b9 ("timers: Forward the wheel clock whenever possible")
Co-developed-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Lingutla Chandrasekhar <clingutla@codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: linux-arm-msm@vger.kernel.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180118115022.6368-1-clingutla@codeaurora.org
wake_klogd is a local variable in console_unlock(). The information
is lost when the console_lock owner using the busy wait added by
the commit dbdda842fe ("printk: Add console owner and waiter
logic to load balance console writes"). The following race is
possible:
CPU0 CPU1
console_unlock()
for (;;)
/* calling console for last message */
printk()
log_store()
log_next_seq++;
/* see new message */
if (seen_seq != log_next_seq) {
wake_klogd = true;
seen_seq = log_next_seq;
}
console_lock_spinning_enable();
if (console_trylock_spinning())
/* spinning */
if (console_lock_spinning_disable_and_check()) {
printk_safe_exit_irqrestore(flags);
return;
console_unlock()
if (seen_seq != log_next_seq) {
/* already seen */
/* nothing to do */
Result: Nobody would wakeup klogd.
One solution would be to make a global variable from wake_klogd.
But then we would need to manipulate it under a lock or so.
This patch wakes klogd also when console_lock is passed to the
spinning waiter. It looks like the right way to go. Also userspace
should have a chance to see and store any "flood" of messages.
Note that the very late klogd wake up was a historic solution.
It made sense on single CPU systems or when sys_syslog() operations
were synchronized using the big kernel lock like in v2.1.113.
But it is questionable these days.
Fixes: dbdda842fe ("printk: Add console owner and waiter logic to load balance console writes")
Link: http://lkml.kernel.org/r/20180226155734.dzwg3aovqnwtvkoy@pathway.suse.cz
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Cc: Tejun Heo <tj@kernel.org>
Suggested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Pull x86 fixes from Thomas Gleixner:
"Yet another pile of melted spectrum related changes:
- sanitize the array_index_nospec protection mechanism: Remove the
overengineered array_index_nospec_mask_check() magic and allow
const-qualified types as index to avoid temporary storage in a
non-const local variable.
- make the microcode loader more robust by properly propagating error
codes. Provide information about new feature bits after micro code
was updated so administrators can act upon.
- optimizations of the entry ASM code which reduce code footprint and
make the code simpler and faster.
- fix the {pmd,pud}_{set,clear}_flags() implementations to work
properly on paravirt kernels by removing the address translation
operations.
- revert the harmful vmexit_fill_RSB() optimization
- use IBRS around firmware calls
- teach objtool about retpolines and add annotations for indirect
jumps and calls.
- explicitly disable jumplabel patching in __init code and handle
patching failures properly instead of silently ignoring them.
- remove indirect paravirt calls for writing the speculation control
MSR as these calls are obviously proving the same attack vector
which is tried to be mitigated.
- a few small fixes which address build issues with recent compiler
and assembler versions"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
KVM/VMX: Optimize vmx_vcpu_run() and svm_vcpu_run() by marking the RDMSR path as unlikely()
KVM/x86: Remove indirect MSR op calls from SPEC_CTRL
objtool, retpolines: Integrate objtool with retpoline support more closely
x86/entry/64: Simplify ENCODE_FRAME_POINTER
extable: Make init_kernel_text() global
jump_label: Warn on failed jump_label patching attempt
jump_label: Explicitly disable jump labels in __init code
x86/entry/64: Open-code switch_to_thread_stack()
x86/entry/64: Move ASM_CLAC to interrupt_entry()
x86/entry/64: Remove 'interrupt' macro
x86/entry/64: Move the switch_to_thread_stack() call to interrupt_entry()
x86/entry/64: Move ENTER_IRQ_STACK from interrupt macro to interrupt_entry
x86/entry/64: Move PUSH_AND_CLEAR_REGS from interrupt macro to helper function
x86/speculation: Move firmware_restrict_branch_speculation_*() from C to CPP
objtool: Add module specific retpoline rules
objtool: Add retpoline validation
objtool: Use existing global variables for options
x86/mm/sme, objtool: Annotate indirect call in sme_encrypt_execute()
x86/boot, objtool: Annotate indirect jump in secondary_startup_64()
x86/paravirt, objtool: Annotate indirect calls
...
Pull x86 fixes from Thomas Gleixner:
"A small set of fixes:
- UAPI data type correction for hyperv
- correct the cpu cores field in /proc/cpuinfo on CPU hotplug
- return proper error code in the resctrl file system failure path to
avoid silent subsequent failures
- correct a subtle accounting issue in the new vector allocation code
which went unnoticed for a while and caused suspend/resume
failures"
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/topology: Update the 'cpu cores' field in /proc/cpuinfo correctly across CPU hotplug operations
x86/topology: Fix function name in documentation
x86/intel_rdt: Fix incorrect returned value when creating rdgroup sub-directory in resctrl file system
x86/apic/vector: Handle vector release on CPU unplug correctly
genirq/matrix: Handle CPU offlining proper
x86/headers/UAPI: Use __u64 instead of u64 in <uapi/asm/hyperv.h>
Pull networking fixes from David Miller:
1) Fix TTL offset calculation in mac80211 mesh code, from Peter Oh.
2) Fix races with procfs in ipt_CLUSTERIP, from Cong Wang.
3) Memory leak fix in lpm_trie BPF map code, from Yonghong Song.
4) Need to use GFP_ATOMIC in BPF cpumap allocations, from Jason Wang.
5) Fix potential deadlocks in netfilter getsockopt() code paths, from
Paolo Abeni.
6) Netfilter stackpointer size checks really are needed to validate
user input, from Florian Westphal.
7) Missing timer init in x_tables, from Paolo Abeni.
8) Don't use WQ_MEM_RECLAIM in mac80211 hwsim, from Johannes Berg.
9) When an ibmvnic device is brought down then back up again, it can be
sent queue entries from a previous session, handle this properly
instead of crashing. From Thomas Falcon.
10) Fix TCP checksum on LRO buffers in mlx5e, from Gal Pressman.
11) When we are dumping filters in cls_api, the output SKB is empty, and
the filter we are dumping is too large for the space in the SKB, we
should return -EMSGSIZE like other netlink dump operations do.
Otherwise userland has no signal that is needs to increase the size
of its read buffer. From Roman Kapl.
12) Several XDP fixes for virtio_net, from Jesper Dangaard Brouer.
13) Module refcount leak in netlink when a dump start fails, from Jason
Donenfeld.
14) Handle sub-optimal GSO sizes better in TCP BBR congestion control,
from Eric Dumazet.
15) Releasing bpf per-cpu arraymaps can take a long time, add a
condtional scheduling point. From Eric Dumazet.
16) Implement retpolines for tail calls in x64 and arm64 bpf JITs. From
Daniel Borkmann.
17) Fix page leak in gianfar driver, from Andy Spencer.
18) Missed clearing of estimator scratch buffer, from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits)
net_sched: gen_estimator: fix broken estimators based on percpu stats
gianfar: simplify FCS handling and fix memory leak
ipv6 sit: work around bogus gcc-8 -Wrestrict warning
macvlan: fix use-after-free in macvlan_common_newlink()
bpf, arm64: fix out of bounds access in tail call
bpf, x64: implement retpoline for tail call
rxrpc: Fix send in rxrpc_send_data_packet()
net: aquantia: Fix error handling in aq_pci_probe()
bpf: fix rcu lockdep warning for lpm_trie map_free callback
bpf: add schedule points in percpu arrays management
regulatory: add NUL to request alpha2
ibmvnic: Fix early release of login buffer
net/smc9194: Remove bogus CONFIG_MAC reference
net: ipv4: Set addr_type in hash_keys for forwarded case
tcp_bbr: better deal with suboptimal GSO
smsc75xx: fix smsc75xx_set_features()
netlink: put module reference if dump start fails
selftests/bpf/test_maps: exit child process without error in ENOMEM case
selftests/bpf: update gitignore with test_libbpf_open
selftests/bpf: tcpbpf_kern: use in6_* macros from glibc
..
Pull security subsystem fixes from James Morris:
- keys fixes via David Howells:
"A collection of fixes for Linux keyrings, mostly thanks to Eric
Biggers:
- Fix some PKCS#7 verification issues.
- Fix handling of unsupported crypto in X.509.
- Fix too-large allocation in big_key"
- Seccomp updates via Kees Cook:
"These are fixes for the get_metadata interface that landed during
-rc1. While the new selftest is strictly not a bug fix, I think
it's in the same spirit of avoiding bugs"
- an IMA build fix from Randy Dunlap
* 'fixes-v4.16-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
integrity/security: fix digsig.c build error with header file
KEYS: Use individual pages in big_key for crypto buffers
X.509: fix NULL dereference when restricting key with unsupported_sig
X.509: fix BUG_ON() when hash algorithm is unsupported
PKCS#7: fix direct verification of SignerInfo signature
PKCS#7: fix certificate blacklisting
PKCS#7: fix certificate chain verification
seccomp: add a selftest for get_metadata
ptrace, seccomp: tweak get_metadata behavior slightly
seccomp, ptrace: switch get_metadata types to arch independent
-----BEGIN PGP SIGNATURE-----
iQIcBAABAgAGBQJaj38KAAoJEAx081l5xIa+AY8P/0oX+UPtjNxVqUTzeejxxZG7
EpmcJWP2SENnkOSdiyPMLI4SIOgv0B+73hX6ATbsVx9nseqxAJyoAFJZCQy7ioS3
RjB6wXi/WQrxrXc3MU5FUp8AfPLvZx2BlAHGqyuk3V2f3fIjl0tWmMuxgdc0WX1j
wzzHNBEKoXG5WVVEOXJZq5xd8s35QTdhqGpqrvl1ruHtqmnls8n67qPB9F7F6lHm
Iwi6MlvIxwoLIuWj0cJyOoUdw0Z6/MQ+Of8zW1E0NJIfgfa9LKjtIRUacJvOndRP
Oq9XUCI/6gmNswmdktz65w1SfuU/cq9j46FuBh23QYNvYfuYgtvL0xhQPYF08vtK
83X1Sop8Pzz9f2jCL2TPKLF37TetNpMT1gTP/NsGirRc+cvZTMBl1+OcWO47oTYZ
TZ70L7GSJOdJV/n5vdCE5bSBS/thvLC5tyUGgRH+y7E6Lt2HouVN3ulkKb/stuQ3
ee9NbI16YXZepK3+Z4YUdFziC40BO7K0LGlyAjs9G95LBRQNq9jNJLXTog5vSUJa
3DFjEqQ558iciGkmYx4cQhlCqYvzuNClutz2D4RN7LqA5wHKqt4LWwTgjnUk9Z82
lvNm3IGB+HiXEWpQmEuQeMqC+Xwxfdx3n+s3I7TpztdbgIWJM4KqAa4OKKK2NUM6
qxEYwcQ2P84obOwBkVu3
=LRdE
-----END PGP SIGNATURE-----
Merge tag 'drm-fixes-for-v4.16-rc3' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"A bunch of fixes for rc3:
Exynos:
- fixes for using monotonic timestamps
- register definitions
- removal of unused file
ipu-v3L
- minor changes
- make some register arrays const+static
- fix some leaks
meson:
- fix for vsync
atomic:
- fix for memory leak
EDID parser:
- add quirks for some more non-desktop devices
- 6-bit panel fix.
drm_mm:
- fix a bug in the core drm mm hole handling
cirrus:
- fix lut loading regression
Lastly there is a deadlock fix around runtime suspend for secondary
GPUs.
There was a deadlock between one thread trying to wait for a workqueue
job to finish in the runtime suspend path, and the workqueue job it
was waiting for in turn waiting for a runtime_get_sync to return.
The fixes avoids it by not doing the runtime sync in the workqueue as
then we always wait for all those tasks to complete before we runtime
suspend"
* tag 'drm-fixes-for-v4.16-rc3' of git://people.freedesktop.org/~airlied/linux: (25 commits)
drm/tve200: fix kernel-doc documentation comment include
drm/edid: quirk Sony PlayStation VR headset as non-desktop
drm/edid: quirk Windows Mixed Reality headsets as non-desktop
drm/edid: quirk Oculus Rift headsets as non-desktop
drm/meson: fix vsync buffer update
drm: Handle unexpected holes in color-eviction
drm: exynos: Use proper macro definition for HDMI_I2S_PIN_SEL_1
drm/exynos: remove exynos_drm_rotator.h
drm/exynos: g2d: Delete an error message for a failed memory allocation in two functions
drm/exynos: fix comparison to bitshift when dealing with a mask
drm/exynos: g2d: use monotonic timestamps
drm/edid: Add 6 bpc quirk for CPT panel in Asus UX303LA
gpu: ipu-csi: add 10/12-bit grayscale support to mbus_code_to_bus_cfg
gpu: ipu-cpmem: add 16-bit grayscale support to ipu_cpmem_set_image
gpu: ipu-v3: prg: fix device node leak in ipu_prg_lookup_by_phandle
gpu: ipu-v3: pre: fix device node leak in ipu_pre_lookup_by_phandle
drm/amdgpu: Fix deadlock on runtime suspend
drm/radeon: Fix deadlock on runtime suspend
drm/nouveau: Fix deadlock on runtime suspend
drm: Allow determining if current task is output poll worker
...
At CPU hotunplug the corresponding per cpu matrix allocator is shut down and
the allocated interrupt bits are discarded under the assumption that all
allocated bits have been either migrated away or shut down through the
managed interrupts mechanism.
This is not true because interrupts which are not started up might have a
vector allocated on the outgoing CPU. When the interrupt is started up
later or completely shutdown and freed then the allocated vector is handed
back, triggering warnings or causing accounting issues which result in
suspend failures and other issues.
Change the CPU hotplug mechanism of the matrix allocator so that the
remaining allocations at unplug time are preserved and global accounting at
hotplug is correctly readjusted to take the dormant vectors into account.
Fixes: 2f75d9e1c9 ("genirq: Implement bitmap matrix allocator")
Reported-by: Yuriy Vostrikov <delamonpansie@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Yuriy Vostrikov <delamonpansie@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180222112316.849980972@linutronix.de
Commit 9a3efb6b66 ("bpf: fix memory leak in lpm_trie map_free callback function")
fixed a memory leak and removed unnecessary locks in map_free callback function.
Unfortrunately, it introduced a lockdep warning. When lockdep checking is turned on,
running tools/testing/selftests/bpf/test_lpm_map will have:
[ 98.294321] =============================
[ 98.294807] WARNING: suspicious RCU usage
[ 98.295359] 4.16.0-rc2+ #193 Not tainted
[ 98.295907] -----------------------------
[ 98.296486] /home/yhs/work/bpf/kernel/bpf/lpm_trie.c:572 suspicious rcu_dereference_check() usage!
[ 98.297657]
[ 98.297657] other info that might help us debug this:
[ 98.297657]
[ 98.298663]
[ 98.298663] rcu_scheduler_active = 2, debug_locks = 1
[ 98.299536] 2 locks held by kworker/2:1/54:
[ 98.300152] #0: ((wq_completion)"events"){+.+.}, at: [<00000000196bc1f0>] process_one_work+0x157/0x5c0
[ 98.301381] #1: ((work_completion)(&map->work)){+.+.}, at: [<00000000196bc1f0>] process_one_work+0x157/0x5c0
Since actual trie tree removal happens only after no other
accesses to the tree are possible, replacing
rcu_dereference_protected(*slot, lockdep_is_held(&trie->lock))
with
rcu_dereference_protected(*slot, 1)
fixed the issue.
Fixes: 9a3efb6b66 ("bpf: fix memory leak in lpm_trie map_free callback function")
Reported-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
syszbot managed to trigger RCU detected stalls in
bpf_array_free_percpu()
It takes time to allocate a huge percpu map, but even more time to free
it.
Since we run in process context, use cond_resched() to yield cpu if
needed.
Fixes: a10423b87a ("bpf: introduce BPF_MAP_TYPE_PERCPU_ARRAY map")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Merge misc fixes from Andrew Morton:
"16 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm: don't defer struct page initialization for Xen pv guests
lib/Kconfig.debug: enable RUNTIME_TESTING_MENU
vmalloc: fix __GFP_HIGHMEM usage for vmalloc_32 on 32b systems
selftests/memfd: add run_fuse_test.sh to TEST_FILES
bug.h: work around GCC PR82365 in BUG()
mm/swap.c: make functions and their kernel-doc agree (again)
mm/zpool.c: zpool_evictable: fix mismatch in parameter name and kernel-doc
ida: do zeroing in ida_pre_get()
mm, swap, frontswap: fix THP swap if frontswap enabled
certs/blacklist_nohashes.c: fix const confusion in certs blacklist
kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE
mm, mlock, vmscan: no more skipping pagevecs
mm: memcontrol: fix NR_WRITEBACK leak in memcg and system stats
Kbuild: always define endianess in kconfig.h
include/linux/sched/mm.h: re-inline mmdrop()
tools: fix cross-compile var clobbering
Each read from a file in efivarfs results in two calls to EFI
(one to get the file size, another to get the actual data).
On X86 these EFI calls result in broadcast system management
interrupts (SMI) which affect performance of the whole system.
A malicious user can loop performing reads from efivarfs bringing
the system to its knees.
Linus suggested per-user rate limit to solve this.
So we add a ratelimit structure to "user_struct" and initialize
it for the root user for no limit. When allocating user_struct for
other users we set the limit to 100 per second. This could be used
for other places that want to limit the rate of some detrimental
user action.
In efivarfs if the limit is exceeded when reading, we take an
interruptible nap for 50ms and check the rate limit again.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Previously if users passed a small size for the input structure size, they
would get get odd behavior. It doesn't make sense to pass a structure
smaller than at least filter_off size, so let's just give -EINVAL in this
case.
This changes userspace visible behavior, but was only introduced in commit
26500475ac ("ptrace, seccomp: add support for retrieving seccomp
metadata") in 4.16-rc2, so should be safe to change if merged before then.
Reported-by: Eugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: Tycho Andersen <tycho@tycho.ws>
CC: Kees Cook <keescook@chromium.org>
CC: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
chan->n_subbufs is set by the user and relay_create_buf() does a kmalloc()
of chan->n_subbufs * sizeof(size_t *).
kmalloc_slab() will generate a warning when this fails if
chan->subbufs * sizeof(size_t *) > KMALLOC_MAX_SIZE.
Limit chan->n_subbufs to the maximum allowed kmalloc() size.
Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1802061216100.122576@chino.kir.corp.google.com
Fixes: f6302f1bcd ("relay: prevent integer overflow in relay_open()")
Signed-off-by: David Rientjes <rientjes@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As Peter points out, Doing a CALL+RET for just the decrement is a bit silly.
Fixes: d70f2a14b7 ("include/linux/sched/mm.h: uninline mmdrop_async(), etc")
Acked-by: Peter Zijlstra (Intel) <peterz@infraded.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers, a memory leak on non-blocking commits, a crash on color-eviction.
The is also meson and edid fixes, plus a fix for a doc warning.
-----BEGIN PGP SIGNATURE-----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=555h
-----END PGP SIGNATURE-----
Merge tag 'drm-misc-fixes-2018-02-21' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes
Fixes for 4.16. I contains fixes for deadlock on runtime suspend on few
drivers, a memory leak on non-blocking commits, a crash on color-eviction.
The is also meson and edid fixes, plus a fix for a doc warning.
* tag 'drm-misc-fixes-2018-02-21' of git://anongit.freedesktop.org/drm/drm-misc:
drm/tve200: fix kernel-doc documentation comment include
drm/meson: fix vsync buffer update
drm: Handle unexpected holes in color-eviction
drm/edid: Add 6 bpc quirk for CPT panel in Asus UX303LA
drm/amdgpu: Fix deadlock on runtime suspend
drm/radeon: Fix deadlock on runtime suspend
drm/nouveau: Fix deadlock on runtime suspend
drm: Allow determining if current task is output poll worker
workqueue: Allow retrieval of current task's work struct
drm/atomic: Fix memleak on ERESTARTSYS during non-blocking commits
Daniel Borkmann says:
====================
pull-request: bpf 2018-02-20
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix a memory leak in LPM trie's map_free() callback function, where
the trie structure itself was not freed since initial implementation.
Also a synchronize_rcu() was needed in order to wait for outstanding
programs accessing the trie to complete, from Yonghong.
2) Fix sock_map_alloc()'s error path in order to correctly propagate
the -EINVAL error in case of too large allocation requests. This
was just recently introduced when fixing close hooks via ULP layer,
fix from Eric.
3) Do not use GFP_ATOMIC in __cpu_map_entry_alloc(). Reason is that this
will not work with the recent __ptr_ring_init_queue_alloc() conversion
to kvmalloc_array(), where in case of fallback to vmalloc() that GFP
flag is invalid, from Jason.
4) Fix two recent syzkaller warnings: i) fix bpf_prog_array_copy_to_user()
when a prog query with a big number of ids was performed where we'd
otherwise trigger a warning from allocator side, ii) fix a missing
mlock precharge on arraymaps, from Daniel.
5) Two fixes for bpftool in order to avoid breaking JSON output when used
in batch mode, from Quentin.
6) Move a pr_debug() in libbpf in order to avoid having an otherwise
uninitialized variable in bpf_program__reloc_text(), from Jeremy.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Convert init_kernel_text() to a global function and use it in a few
places instead of manually comparing _sinittext and _einittext.
Note that kallsyms.h has a very similar function called
is_kernel_inittext(), but its end check is inclusive. I'm not sure
whether that's intentional behavior, so I didn't touch it.
Suggested-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/4335d02be8d45ca7d265d2f174251d0b7ee6c5fd.1519051220.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently when the jump label code encounters an address which isn't
recognized by kernel_text_address(), it just silently fails.
This can be dangerous because jump labels are used in a variety of
places, and are generally expected to work. Convert the silent failure
to a warning.
This won't warn about attempted writes to tracepoints in __init code
after initmem has been freed, as those are already guarded by the
entry->code check.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/de3a271c93807adb7ed48f4e946b4f9156617680.1519051220.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
After initmem has been freed, any jump labels in __init code are
prevented from being written to by the kernel_text_address() check in
__jump_label_update(). However, this check is quite broad. If
kernel_text_address() were to return false for any other reason, the
jump label write would fail silently with no warning.
For jump labels in module init code, entry->code is set to zero to
indicate that the entry is disabled. Do the same thing for core kernel
init code. This makes the behavior more consistent, and will also make
it more straightforward to detect non-init jump label write failures in
the next patch.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/c52825c73f3a174e8398b6898284ec20d4deb126.1519051220.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf updates from Thomas Gleixner:
"Perf tool updates and kprobe fixes:
- perf_mmap overwrite mode fixes/overhaul, prep work to get 'perf
top' using it, making it bearable to use it in large core count
systems such as Knights Landing/Mill Intel systems (Kan Liang)
- s/390 now uses syscall.tbl, just like x86-64 to generate the
syscall table id -> string tables used by 'perf trace' (Hendrik
Brueckner)
- Use strtoull() instead of home grown function (Andy Shevchenko)
- Synchronize kernel ABI headers, v4.16-rc1 (Ingo Molnar)
- Document missing 'perf data --force' option (Sangwon Hong)
- Add perf vendor JSON metrics for ARM Cortex-A53 Processor (William
Cohen)
- Improve error handling and error propagation of ftrace based
kprobes so failures when installing kprobes are not silently
ignored and create disfunctional tracepoints"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
kprobes: Propagate error from disarm_kprobe_ftrace()
kprobes: Propagate error from arm_kprobe_ftrace()
Revert "tools include s390: Grab a copy of arch/s390/include/uapi/asm/unistd.h"
perf s390: Rework system call table creation by using syscall.tbl
perf s390: Grab a copy of arch/s390/kernel/syscall/syscall.tbl
tools/headers: Synchronize kernel ABI headers, v4.16-rc1
perf test: Fix test trace+probe_libc_inet_pton.sh for s390x
perf data: Document missing --force option
perf tools: Substitute yet another strtoull()
perf top: Check the latency of perf_top__mmap_read()
perf top: Switch default mode to overwrite mode
perf top: Remove lost events checking
perf hists browser: Add parameter to disable lost event warning
perf top: Add overwrite fall back
perf evsel: Expose the perf_missing_features struct
perf top: Check per-event overwrite term
perf mmap: Discard legacy interface for mmap read
perf test: Update mmap read functions for backward-ring-buffer test
perf mmap: Introduce perf_mmap__read_event()
perf mmap: Introduce perf_mmap__read_done()
...
Pull irq updates from Thomas Gleixner:
"A small set of updates mostly for irq chip drivers:
- MIPS GIC fix for spurious, masked interrupts
- fix for a subtle IPI bug in GICv3
- do not probe GICv3 ITSs that are marked as disabled
- multi-MSI support for GICv2m
- various small cleanups"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqdomain: Re-use DEFINE_SHOW_ATTRIBUTE() macro
irqchip/bcm: Remove hashed address printing
irqchip/gic-v2m: Add PCI Multi-MSI support
irqchip/gic-v3: Ignore disabled ITS nodes
irqchip/gic-v3: Use wmb() instead of smb_wmb() in gic_raise_softirq()
irqchip/gic-v3: Change pr_debug message to pr_devel
irqchip/mips-gic: Avoid spuriously handling masked interrupts
Introduce a helper to retrieve the current task's work struct if it is
a workqueue worker.
This allows us to fix a long-standing deadlock in several DRM drivers
wherein the ->runtime_suspend callback waits for a specific worker to
finish and that worker in turn calls a function which waits for runtime
suspend to finish. That function is invoked from multiple call sites
and waiting for runtime suspend to finish is the correct thing to do
except if it's executing in the context of the worker.
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://patchwork.freedesktop.org/patch/msgid/2d8f603074131eb87e588d2b803a71765bd3a2fd.1518338788.git.lukas@wunner.de
...instead of open coding file operations followed by custom ->open()
callbacks per each attribute.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Improve error handling when disarming ftrace-based kprobes. Like with
arm_kprobe_ftrace(), propagate any errors from disarm_kprobe_ftrace() so
that we do not disable/unregister kprobes that are still armed. In other
words, unregister_kprobe() and disable_kprobe() should not report success
if the kprobe could not be disarmed.
disarm_all_kprobes() keeps its current behavior and attempts to
disarm all kprobes. It returns the last encountered error and gives a
warning if not all probes could be disarmed.
This patch is based on Petr Mladek's original patchset (patches 2 and 3)
back in 2015, which improved kprobes error handling, found here:
https://lkml.org/lkml/2015/2/26/452
However, further work on this had been paused since then and the patches
were not upstreamed.
Based-on-patches-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/20180109235124.30886-3-jeyu@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Improve error handling when arming ftrace-based kprobes. Specifically, if
we fail to arm a ftrace-based kprobe, register_kprobe()/enable_kprobe()
should report an error instead of success. Previously, this has lead to
confusing situations where register_kprobe() would return 0 indicating
success, but the kprobe would not be functional if ftrace registration
during the kprobe arming process had failed. We should therefore take any
errors returned by ftrace into account and propagate this error so that we
do not register/enable kprobes that cannot be armed. This can happen if,
for example, register_ftrace_function() finds an IPMODIFY conflict (since
kprobe_ftrace_ops has this flag set) and returns an error. Such a conflict
is possible since livepatches also set the IPMODIFY flag for their ftrace_ops.
arm_all_kprobes() keeps its current behavior and attempts to arm all
kprobes. It returns the last encountered error and gives a warning if
not all probes could be armed.
This patch is based on Petr Mladek's original patchset (patches 2 and 3)
back in 2015, which improved kprobes error handling, found here:
https://lkml.org/lkml/2015/2/26/452
However, further work on this had been paused since then and the patches
were not upstreamed.
Based-on-patches-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/20180109235124.30886-2-jeyu@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
syzkaller recently triggered OOM during percpu map allocation;
while there is work in progress by Dennis Zhou to add __GFP_NORETRY
semantics for percpu allocator under pressure, there seems also a
missing bpf_map_precharge_memlock() check in array map allocation.
Given today the actual bpf_map_charge_memlock() happens after the
find_and_alloc_map() in syscall path, the bpf_map_precharge_memlock()
is there to bail out early before we go and do the map setup work
when we find that we hit the limits anyway. Therefore add this for
array map as well.
Fixes: 6c90598174 ("bpf: pre-allocate hash map elements")
Fixes: a10423b87a ("bpf: introduce BPF_MAP_TYPE_PERCPU_ARRAY map")
Reported-by: syzbot+adb03f3f0bb57ce3acda@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Dennis Zhou <dennisszhou@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pull locking fixes from Ingo Molnar:
"This contains two qspinlock fixes and three documentation and comment
fixes"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/semaphore: Update the file path in documentation
locking/atomic/bitops: Document and clarify ordering semantics for failed test_and_{}_bit()
locking/qspinlock: Ensure node->count is updated before initialising node
locking/qspinlock: Ensure node is initialised before updating prev->next
Documentation/locking/mutex-design: Update to reflect latest changes
syzkaller tried to perform a prog query in perf_event_query_prog_array()
where struct perf_event_query_bpf had an ids_len of 1,073,741,353 and
thus causing a warning due to failed kcalloc() allocation out of the
bpf_prog_array_copy_to_user() helper. Given we cannot attach more than
64 programs to a perf event, there's no point in allowing huge ids_len.
Therefore, allow a buffer that would fix the maximum number of ids and
also add a __GFP_NOWARN to the temporary ids buffer.
Fixes: f371b304f1 ("bpf/tracing: allow user space to query prog array on the same tp")
Fixes: 0911287ce3 ("bpf: fix bpf_prog_array_copy_to_user() issues")
Reported-by: syzbot+cab5816b0edbabf598b3@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There're several implications after commit 0bf7800f17 ("ptr_ring:
try vmalloc() when kmalloc() fails") with the using of vmalloc() since
can't allow GFP_ATOMIC but mandate GFP_KERNEL. This will lead a WARN
since cpumap try to call with GFP_ATOMIC. Fortunately, entry
allocation of cpumap can only be done through syscall path which means
GFP_ATOMIC is not necessary, so fixing this by replacing GFP_ATOMIC
with GFP_KERNEL.
Reported-by: syzbot+1a240cdb1f4cc88819df@syzkaller.appspotmail.com
Fixes: 0bf7800f17 ("ptr_ring: try vmalloc() when kmalloc() fails")
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: akpm@linux-foundation.org
Cc: dhowells@redhat.com
Cc: hannes@cmpxchg.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
In case user program provides silly parameters, we want
a map_alloc() handler to return an error, not a NULL pointer,
otherwise we crash later in find_and_alloc_map()
Fixes: 1aa12bdf1b ("bpf: sockmap, add sock close() hook to remove socks")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There is a memory leak happening in lpm_trie map_free callback
function trie_free. The trie structure itself does not get freed.
Also, trie_free function did not do synchronize_rcu before freeing
various data structures. This is incorrect as some rcu_read_lock
region(s) for lookup, update, delete or get_next_key may not complete yet.
The fix is to add synchronize_rcu in the beginning of trie_free.
The useless spin_lock is removed from this function as well.
Fixes: b95a5c4db0 ("bpf: add a longest prefix match trie map implementation")
Reported-by: Mathieu Malaterre <malat@debian.org>
Reported-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
When queuing on the qspinlock, the count field for the current CPU's head
node is incremented. This needn't be atomic because locking in e.g. IRQ
context is balanced and so an IRQ will return with node->count as it
found it.
However, the compiler could in theory reorder the initialisation of
node[idx] before the increment of the head node->count, causing an
IRQ to overwrite the initialised node and potentially corrupt the lock
state.
Avoid the potential for this harmful compiler reordering by placing a
barrier() between the increment of the head node->count and the subsequent
node initialisation.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1518528177-19169-3-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When a locker ends up queuing on the qspinlock locking slowpath, we
initialise the relevant mcs node and publish it indirectly by updating
the tail portion of the lock word using xchg_tail. If we find that there
was a pre-existing locker in the queue, we subsequently update their
->next field to point at our node so that we are notified when it's our
turn to take the lock.
This can be roughly illustrated as follows:
/* Initialise the fields in node and encode a pointer to node in tail */
tail = initialise_node(node);
/*
* Exchange tail into the lockword using an atomic read-modify-write
* operation with release semantics
*/
old = xchg_tail(lock, tail);
/* If there was a pre-existing waiter ... */
if (old & _Q_TAIL_MASK) {
prev = decode_tail(old);
smp_read_barrier_depends();
/* ... then update their ->next field to point to node.
WRITE_ONCE(prev->next, node);
}
The conditional update of prev->next therefore relies on the address
dependency from the result of xchg_tail ensuring order against the
prior initialisation of node. However, since the release semantics of
the xchg_tail operation apply only to the write portion of the RmW,
then this ordering is not guaranteed and it is possible for the CPU
to return old before the writes to node have been published, consequently
allowing us to point prev->next to an uninitialised node.
This patch fixes the problem by making the update of prev->next a RELEASE
operation, which also removes the reliance on dependency ordering.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1518528177-19169-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since schedutil kernel thread directly set priority to 0, the macro
SUGOV_KTHREAD_PRIORITY is not used. So remove it.
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vikram Mulukutla <markivx@codeaurora.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Link: http://lkml.kernel.org/r/1518097702-9665-1-git-send-email-leo.yan@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Mark noticed that he had sporadic "spinlock recursion" warnings from
the DEBUG_SPINLOCK code. Now rq->lock is special in that the owner
changes in the middle of a context switch.
It so happens that we fix up the lock.owner too late, @prev can run
(remotely) the moment prev->on_cpu is cleared, this then allows @prev
to again try and acquire this rq->lock and trigger this warning.
So we have to switch lock.owner before clearing prev->on_cpu.
Do this by moving the DEBUG_SPINLOCK annotation from after switch_to()
to before switch_to() and collect all lockdep annotations there into
prepare_lock_switch() to mirror the existing finish_lock_switch().
Debugged-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tom Zanussi