The only slightly tricky merge conflict was the netdevsim because the
mutex locking fix overlapped a lot of driver reload reorganization.
The rest were (relatively) trivial in nature.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Fix free/alloc races in batmanadv, from Sven Eckelmann.
2) Several leaks and other fixes in kTLS support of mlx5 driver, from
Tariq Toukan.
3) BPF devmap_hash cost calculation can overflow on 32-bit, from Toke
Høiland-Jørgensen.
4) Add an r8152 device ID, from Kazutoshi Noguchi.
5) Missing include in ipv6's addrconf.c, from Ben Dooks.
6) Use siphash in flow dissector, from Eric Dumazet. Attackers can
easily infer the 32-bit secret otherwise etc.
7) Several netdevice nesting depth fixes from Taehee Yoo.
8) Fix several KCSAN reported errors, from Eric Dumazet. For example,
when doing lockless skb_queue_empty() checks, and accessing
sk_napi_id/sk_incoming_cpu lockless as well.
9) Fix jumbo packet handling in RXRPC, from David Howells.
10) Bump SOMAXCONN and tcp_max_syn_backlog values, from Eric Dumazet.
11) Fix DMA synchronization in gve driver, from Yangchun Fu.
12) Several bpf offload fixes, from Jakub Kicinski.
13) Fix sk_page_frag() recursion during memory reclaim, from Tejun Heo.
14) Fix ping latency during high traffic rates in hisilicon driver, from
Jiangfent Xiao.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (146 commits)
net: fix installing orphaned programs
net: cls_bpf: fix NULL deref on offload filter removal
selftests: bpf: Skip write only files in debugfs
selftests: net: reuseport_dualstack: fix uninitalized parameter
r8169: fix wrong PHY ID issue with RTL8168dp
net: dsa: bcm_sf2: Fix IMP setup for port different than 8
net: phylink: Fix phylink_dbg() macro
gve: Fixes DMA synchronization.
inet: stop leaking jiffies on the wire
ixgbe: Remove duplicate clear_bit() call
Documentation: networking: device drivers: Remove stray asterisks
e1000: fix memory leaks
i40e: Fix receive buffer starvation for AF_XDP
igb: Fix constant media auto sense switching when no cable is connected
net: ethernet: arc: add the missed clk_disable_unprepare
igb: Enable media autosense for the i350.
igb/igc: Don't warn on fatal read failures when the device is removed
tcp: increase tcp_max_syn_backlog max value
net: increase SOMAXCONN to 4096
netdevsim: Fix use-after-free during device dismantle
...
Pull scheduler fixes from Ingo Molnar:
"Fix two scheduler topology bugs/oversights on Juno r0 2+4 big.LITTLE
systems"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/topology: Allow sched_asym_cpucapacity to be disabled
sched/topology: Don't try to build empty sched domains
While the static key is correctly initialized as being disabled, it will
remain forever enabled once turned on. This means that if we start with an
asymmetric system and hotplug out enough CPUs to end up with an SMP system,
the static key will remain set - which is obviously wrong. We should detect
this and turn off things like misfit migration and capacity aware wakeups.
As Quentin pointed out, having separate root domains makes this slightly
trickier. We could have exclusive cpusets that create an SMP island - IOW,
the domains within this root domain will not see any asymmetry. This means
we can't just disable the key on domain destruction, we need to count how
many asymmetric root domains we have.
Consider the following example using Juno r0 which is 2+4 big.LITTLE, where
two identical cpusets are created: they both span both big and LITTLE CPUs:
asym0 asym1
[ ][ ]
L L B L L B
$ cgcreate -g cpuset:asym0
$ cgset -r cpuset.cpus=0,1,3 asym0
$ cgset -r cpuset.mems=0 asym0
$ cgset -r cpuset.cpu_exclusive=1 asym0
$ cgcreate -g cpuset:asym1
$ cgset -r cpuset.cpus=2,4,5 asym1
$ cgset -r cpuset.mems=0 asym1
$ cgset -r cpuset.cpu_exclusive=1 asym1
$ cgset -r cpuset.sched_load_balance=0 .
(the CPU numbering may look odd because on the Juno LITTLEs are CPUs 0,3-5
and bigs are CPUs 1-2)
If we make one of those SMP (IOW remove asymmetry) by e.g. hotplugging its
big core, we would end up with an SMP cpuset and an asymmetric cpuset - the
static key must remain set, because we still have one asymmetric root domain.
With the above example, this could be done with:
$ echo 0 > /sys/devices/system/cpu/cpu2/online
Which would result in:
asym0 asym1
[ ][ ]
L L B L L
When both SMP and asymmetric cpusets are present, all CPUs will observe
sched_asym_cpucapacity being set (it is system-wide), but not all CPUs
observe asymmetry in their sched domain hierarchy:
per_cpu(sd_asym_cpucapacity, <any CPU in asym0>) == <some SD at DIE level>
per_cpu(sd_asym_cpucapacity, <any CPU in asym1>) == NULL
Change the simple key enablement to an increment, and decrement the key
counter when destroying domains that cover asymmetric CPUs.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Dietmar.Eggemann@arm.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hannes@cmpxchg.org
Cc: lizefan@huawei.com
Cc: morten.rasmussen@arm.com
Cc: qperret@google.com
Cc: tj@kernel.org
Cc: vincent.guittot@linaro.org
Fixes: df054e8445 ("sched/topology: Add static_key for asymmetric CPU capacity optimizations")
Link: https://lkml.kernel.org/r/20191023153745.19515-3-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull timer fixes from Thomas Gleixner:
"A small set of fixes for time(keeping):
- Add a missing include to prevent compiler warnings.
- Make the VDSO implementation of clock_getres() POSIX compliant
again. A recent change dropped the NULL pointer guard which is
required as NULL is a valid pointer value for this function.
- Fix two function documentation typos"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
posix-cpu-timers: Fix two trivial comments
timers/sched_clock: Include local timekeeping.h for missing declarations
lib/vdso: Make clock_getres() POSIX compliant again
Pull perf fixes from Thomas Gleixner:
"A set of perf fixes:
kernel:
- Unbreak the tracking of auxiliary buffer allocations which got
imbalanced causing recource limit failures.
- Fix the fallout of splitting of ToPA entries which missed to shift
the base entry PA correctly.
- Use the correct context to lookup the AUX event when unmapping the
associated AUX buffer so the event can be stopped and the buffer
reference dropped.
tools:
- Fix buildiid-cache mode setting in copyfile_mode_ns() when copying
/proc/kcore
- Fix freeing id arrays in the event list so the correct event is
closed.
- Sync sched.h anc kvm.h headers with the kernel sources.
- Link jvmti against tools/lib/ctype.o to have weak strlcpy().
- Fix multiple memory and file descriptor leaks, found by coverity in
perf annotate.
- Fix leaks in error handling paths in 'perf c2c', 'perf kmem', found
by a static analysis tool"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/aux: Fix AUX output stopping
perf/aux: Fix tracking of auxiliary trace buffer allocation
perf/x86/intel/pt: Fix base for single entry topa
perf kmem: Fix memory leak in compact_gfp_flags()
tools headers UAPI: Sync sched.h with the kernel
tools headers kvm: Sync kvm.h headers with the kernel sources
tools headers kvm: Sync kvm headers with the kernel sources
tools headers kvm: Sync kvm headers with the kernel sources
perf c2c: Fix memory leak in build_cl_output()
perf tools: Fix mode setting in copyfile_mode_ns()
perf annotate: Fix multiple memory and file descriptor leaks
perf tools: Fix resource leak of closedir() on the error paths
perf evlist: Fix fix for freed id arrays
perf jvmti: Link against tools/lib/ctype.h to have weak strlcpy()
Daniel Borkmann says:
====================
pull-request: bpf-next 2019-10-27
The following pull-request contains BPF updates for your *net-next* tree.
We've added 52 non-merge commits during the last 11 day(s) which contain
a total of 65 files changed, 2604 insertions(+), 1100 deletions(-).
The main changes are:
1) Revolutionize BPF tracing by using in-kernel BTF to type check BPF
assembly code. The work here teaches BPF verifier to recognize
kfree_skb()'s first argument as 'struct sk_buff *' in tracepoints
such that verifier allows direct use of bpf_skb_event_output() helper
used in tc BPF et al (w/o probing memory access) that dumps skb data
into perf ring buffer. Also add direct loads to probe memory in order
to speed up/replace bpf_probe_read() calls, from Alexei Starovoitov.
2) Big batch of changes to improve libbpf and BPF kselftests. Besides
others: generalization of libbpf's CO-RE relocation support to now
also include field existence relocations, revamp the BPF kselftest
Makefile to add test runner concept allowing to exercise various
ways to build BPF programs, and teach bpf_object__open() and friends
to automatically derive BPF program type/expected attach type from
section names to ease their use, from Andrii Nakryiko.
3) Fix deadlock in stackmap's build-id lookup on rq_lock(), from Song Liu.
4) Allow to read BTF as raw data from bpftool. Most notable use case
is to dump /sys/kernel/btf/vmlinux through this, from Jiri Olsa.
5) Use bpf_redirect_map() helper in libbpf's AF_XDP helper prog which
manages to improve "rx_drop" performance by ~4%., from Björn Töpel.
6) Fix to restore the flow dissector after reattach BPF test and also
fix error handling in bpf_helper_defs.h generation, from Jakub Sitnicki.
7) Improve verifier's BTF ctx access for use outside of raw_tp, from
Martin KaFai Lau.
8) Improve documentation for AF_XDP with new sections and to reflect
latest features, from Magnus Karlsson.
9) Add back 'version' section parsing to libbpf for old kernels, from
John Fastabend.
10) Fix strncat bounds error in libbpf's libbpf_prog_type_by_name(),
from KP Singh.
11) Turn on -mattr=+alu32 in LLVM by default for BPF kselftests in order
to improve insn coverage for built BPF progs, from Yonghong Song.
12) Misc minor cleanups and fixes, from various others.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf 2019-10-27
The following pull-request contains BPF updates for your *net* tree.
We've added 7 non-merge commits during the last 11 day(s) which contain
a total of 7 files changed, 66 insertions(+), 16 deletions(-).
The main changes are:
1) Fix two use-after-free bugs in relation to RCU in jited symbol exposure to
kallsyms, from Daniel Borkmann.
2) Fix NULL pointer dereference in AF_XDP rx-only sockets, from Magnus Karlsson.
3) Fix hang in netdev unregister for hash based devmap as well as another overflow
bug on 32 bit archs in memlock cost calculation, from Toke Høiland-Jørgensen.
4) Fix wrong memory access in LWT BPF programs on reroute due to invalid dst.
Also fix BPF selftests to use more compatible nc options, from Jiri Benc.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch makes a few changes to btf_ctx_access() to prepare
it for non raw_tp use case where the attach_btf_id is not
necessary a BTF_KIND_TYPEDEF.
It moves the "btf_trace_" prefix check and typedef-follow logic to a new
function "check_attach_btf_id()" which is called only once during
bpf_check(). btf_ctx_access() only operates on a BTF_KIND_FUNC_PROTO
type now. That should also be more efficient since it is done only
one instead of every-time check_ctx_access() is called.
"check_attach_btf_id()" needs to find the func_proto type from
the attach_btf_id. It needs to store the result into the
newly added prog->aux->attach_func_proto. func_proto
btf type has no name, so a proper name should be stored into
"attach_func_name" also.
v2:
- Move the "btf_trace_" check to an earlier verifier phase (Alexei)
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191025001811.1718491-1-kafai@fb.com
Pull power management fixes from Rafael Wysocki:
"These fix problems related to frequency limits management in cpufreq
that were introduced during the 5.3 cycle (when PM QoS had started to
be used for that), fix a few issues in the OPP (operating performance
points) library code and fix up the recently added haltpoll cpuidle
driver.
The cpufreq changes are somewhat bigger that I would like them to be
at this stage of the cycle, but the problems fixed by them include
crashes on boot and shutdown in some cases (among other things) and in
my view it is better to address the root of the issue right away.
Specifics:
- Using device PM QoS of CPU devices for managing frequency limits in
cpufreq does not work, so introduce frequency QoS (based on the
original low-level PM QoS) for this purpose, switch cpufreq and
related code over to using it and fix a race involving deferred
updates of frequency limits on top of that (Rafael Wysocki, Sudeep
Holla).
- Avoid calling regulator_enable()/disable() from the OPP framework
to avoid side-effects on boot-enabled regulators that may change
their initial voltage due to performing initial voltage balancing
without all restrictions from the consumers (Marek Szyprowski).
- Avoid a kref management issue in the OPP library code and drop an
incorrectly added lockdep_assert_held() from it (Viresh Kumar).
- Make the recently added haltpoll cpuidle driver take the 'idle='
override into account as appropriate (Zhenzhong Duan)"
* tag 'pm-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
opp: Reinitialize the list_kref before adding the static OPPs again
cpufreq: Cancel policy update work scheduled before freeing
cpuidle: haltpoll: Take 'idle=' override into account
opp: core: Revert "add regulators enable and disable"
PM: QoS: Drop frequency QoS types from device PM QoS
cpufreq: Use per-policy frequency QoS
PM: QoS: Introduce frequency QoS
opp: of: drop incorrect lockdep_assert_held()
Pull tracing fixes from Steven Rostedt:
"Two minor fixes:
- A race in perf trace initialization (missing mutexes)
- Minor fix to represent gfp_t in synthetic events as properly
signed"
* tag 'trace-v5.4-rc3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix race in perf_trace_buf initialization
tracing: Fix "gfp_t" format for synthetic events
Recent changes modified the function arguments of
thread_group_sample_cputime() and task_cputimers_expired(), but forgot to
update the comments. Fix it up.
[ tglx: Changed the argument name of task_cputimers_expired() as the pointer
points to an array of samples. ]
Fixes: b7be4ef136 ("posix-cpu-timers: Switch thread group sampling to array")
Fixes: 001f797143 ("posix-cpu-timers: Make expiry checks array based")
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1571643852-21848-1-git-send-email-wang.yi59@zte.com.cn
Include the timekeeping.h header to get the declaration of the
sched_clock_{suspend,resume} functions. Fixes the following sparse
warnings:
kernel/time/sched_clock.c:275:5: warning: symbol 'sched_clock_suspend' was not declared. Should it be static?
kernel/time/sched_clock.c:286:6: warning: symbol 'sched_clock_resume' was not declared. Should it be static?
Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191022131226.11465-1-ben.dooks@codethink.co.uk
There is one more problematic case I noticed while recently fixing BPF kallsyms
handling in cd7455f101 ("bpf: Fix use after free in subprog's jited symbol
removal") and that is bpf_get_prog_name().
If BTF has been attached to the prog, then we may be able to fetch the function
signature type id in kallsyms through prog->aux->func_info[prog->aux->func_idx].type_id.
However, while the BTF object itself is torn down via RCU callback, the prog's
aux->func_info is immediately freed via kvfree(prog->aux->func_info) once the
prog's refcount either hit zero or when subprograms were already exposed via
kallsyms and we hit the error path added in 5482e9a93c ("bpf: Fix memleak in
aux->func_info and aux->btf").
This violates RCU as well since kallsyms could be walked in parallel where we
could access aux->func_info. Hence, defer kvfree() to after RCU grace period.
Looking at ba64e7d852 ("bpf: btf: support proper non-jit func info") there
is no reason/dependency where we couldn't defer the kvfree(aux->func_info) into
the RCU callback.
Fixes: 5482e9a93c ("bpf: Fix memleak in aux->func_info and aux->btf")
Fixes: ba64e7d852 ("bpf: btf: support proper non-jit func info")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/875f2906a7c1a0691f2d567b4d8e4ea2739b1e88.1571779205.git.daniel@iogearbox.net
syzkaller managed to trigger the following crash:
[...]
BUG: unable to handle page fault for address: ffffc90001923030
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD aa551067 P4D aa551067 PUD aa552067 PMD a572b067 PTE 80000000a1173163
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 7982 Comm: syz-executor912 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:bpf_jit_binary_hdr include/linux/filter.h:787 [inline]
RIP: 0010:bpf_get_prog_addr_region kernel/bpf/core.c:531 [inline]
RIP: 0010:bpf_tree_comp kernel/bpf/core.c:600 [inline]
RIP: 0010:__lt_find include/linux/rbtree_latch.h:115 [inline]
RIP: 0010:latch_tree_find include/linux/rbtree_latch.h:208 [inline]
RIP: 0010:bpf_prog_kallsyms_find kernel/bpf/core.c:674 [inline]
RIP: 0010:is_bpf_text_address+0x184/0x3b0 kernel/bpf/core.c:709
[...]
Call Trace:
kernel_text_address kernel/extable.c:147 [inline]
__kernel_text_address+0x9a/0x110 kernel/extable.c:102
unwind_get_return_address+0x4c/0x90 arch/x86/kernel/unwind_frame.c:19
arch_stack_walk+0x98/0xe0 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0xb6/0x150 kernel/stacktrace.c:123
save_stack mm/kasan/common.c:69 [inline]
set_track mm/kasan/common.c:77 [inline]
__kasan_kmalloc+0x11c/0x1b0 mm/kasan/common.c:510
kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:518
slab_post_alloc_hook mm/slab.h:584 [inline]
slab_alloc mm/slab.c:3319 [inline]
kmem_cache_alloc+0x1f5/0x2e0 mm/slab.c:3483
getname_flags+0xba/0x640 fs/namei.c:138
getname+0x19/0x20 fs/namei.c:209
do_sys_open+0x261/0x560 fs/open.c:1091
__do_sys_open fs/open.c:1115 [inline]
__se_sys_open fs/open.c:1110 [inline]
__x64_sys_open+0x87/0x90 fs/open.c:1110
do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
[...]
After further debugging it turns out that we walk kallsyms while in parallel
we tear down a BPF program which contains subprograms that have been JITed
though the program itself has not been fully exposed and is eventually bailing
out with error.
The bpf_prog_kallsyms_del_subprogs() in bpf_prog_load()'s error path removes
the symbols, however, bpf_prog_free() tears down the JIT memory too early via
scheduled work. Instead, it needs to properly respect RCU grace period as the
kallsyms walk for BPF is under RCU.
Fix it by refactoring __bpf_prog_put()'s tear down and reuse it in our error
path where we defer final destruction when we have subprogs in the program.
Fixes: 7d1982b4e3 ("bpf: fix panic in prog load calls cleanup")
Fixes: 1c2a088a66 ("bpf: x64: add JIT support for multi-function programs")
Reported-by: syzbot+710043c5d1d5b5013bc7@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: syzbot+710043c5d1d5b5013bc7@syzkaller.appspotmail.com
Link: https://lore.kernel.org/bpf/55f6367324c2d7e9583fa9ccf5385dcbba0d7a6e.1571752452.git.daniel@iogearbox.net
Commit:
8a58ddae23 ("perf/core: Fix exclusive events' grouping")
allows CAP_EXCLUSIVE events to be grouped with other events. Since all
of those also happen to be AUX events (which is not the case the other
way around, because arch/s390), this changes the rules for stopping the
output: the AUX event may not be on its PMU's context any more, if it's
grouped with a HW event, in which case it will be on that HW event's
context instead. If that's the case, munmap() of the AUX buffer can't
find and stop the AUX event, potentially leaving the last reference with
the atomic context, which will then end up freeing the AUX buffer. This
will then trip warnings:
Fix this by using the context's PMU context when looking for events
to stop, instead of the event's PMU context.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20191022073940.61814-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The following commit from the v5.4 merge window:
d44248a413 ("perf/core: Rework memory accounting in perf_mmap()")
... breaks auxiliary trace buffer tracking.
If I run command 'perf record -e rbd000' to record samples and saving
them in the **auxiliary** trace buffer then the value of 'locked_vm' becomes
negative after all trace buffers have been allocated and released:
During allocation the values increase:
[52.250027] perf_mmap user->locked_vm:0x87 pinned_vm:0x0 ret:0
[52.250115] perf_mmap user->locked_vm:0x107 pinned_vm:0x0 ret:0
[52.250251] perf_mmap user->locked_vm:0x188 pinned_vm:0x0 ret:0
[52.250326] perf_mmap user->locked_vm:0x208 pinned_vm:0x0 ret:0
[52.250441] perf_mmap user->locked_vm:0x289 pinned_vm:0x0 ret:0
[52.250498] perf_mmap user->locked_vm:0x309 pinned_vm:0x0 ret:0
[52.250613] perf_mmap user->locked_vm:0x38a pinned_vm:0x0 ret:0
[52.250715] perf_mmap user->locked_vm:0x408 pinned_vm:0x2 ret:0
[52.250834] perf_mmap user->locked_vm:0x408 pinned_vm:0x83 ret:0
[52.250915] perf_mmap user->locked_vm:0x408 pinned_vm:0x103 ret:0
[52.251061] perf_mmap user->locked_vm:0x408 pinned_vm:0x184 ret:0
[52.251146] perf_mmap user->locked_vm:0x408 pinned_vm:0x204 ret:0
[52.251299] perf_mmap user->locked_vm:0x408 pinned_vm:0x285 ret:0
[52.251383] perf_mmap user->locked_vm:0x408 pinned_vm:0x305 ret:0
[52.251544] perf_mmap user->locked_vm:0x408 pinned_vm:0x386 ret:0
[52.251634] perf_mmap user->locked_vm:0x408 pinned_vm:0x406 ret:0
[52.253018] perf_mmap user->locked_vm:0x408 pinned_vm:0x487 ret:0
[52.253197] perf_mmap user->locked_vm:0x408 pinned_vm:0x508 ret:0
[52.253374] perf_mmap user->locked_vm:0x408 pinned_vm:0x589 ret:0
[52.253550] perf_mmap user->locked_vm:0x408 pinned_vm:0x60a ret:0
[52.253726] perf_mmap user->locked_vm:0x408 pinned_vm:0x68b ret:0
[52.253903] perf_mmap user->locked_vm:0x408 pinned_vm:0x70c ret:0
[52.254084] perf_mmap user->locked_vm:0x408 pinned_vm:0x78d ret:0
[52.254263] perf_mmap user->locked_vm:0x408 pinned_vm:0x80e ret:0
The value of user->locked_vm increases to a limit then the memory
is tracked by pinned_vm.
During deallocation the size is subtracted from pinned_vm until
it hits a limit. Then a larger value is subtracted from locked_vm
leading to a large number (because of type unsigned):
[64.267797] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x78d
[64.267826] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x70c
[64.267848] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x68b
[64.267869] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x60a
[64.267891] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x589
[64.267911] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x508
[64.267933] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x487
[64.267952] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x406
[64.268883] perf_mmap_close mmap_user->locked_vm:0x307 pinned_vm:0x406
[64.269117] perf_mmap_close mmap_user->locked_vm:0x206 pinned_vm:0x406
[64.269433] perf_mmap_close mmap_user->locked_vm:0x105 pinned_vm:0x406
[64.269536] perf_mmap_close mmap_user->locked_vm:0x4 pinned_vm:0x404
[64.269797] perf_mmap_close mmap_user->locked_vm:0xffffffffffffff84 pinned_vm:0x303
[64.270105] perf_mmap_close mmap_user->locked_vm:0xffffffffffffff04 pinned_vm:0x202
[64.270374] perf_mmap_close mmap_user->locked_vm:0xfffffffffffffe84 pinned_vm:0x101
[64.270628] perf_mmap_close mmap_user->locked_vm:0xfffffffffffffe04 pinned_vm:0x0
This value sticks for the user until system is rebooted, causing
follow-on system calls using locked_vm resource limit to fail.
Note: There is no issue using the normal trace buffer.
In fact the issue is in perf_mmap_close(). During allocation auxiliary
trace buffer memory is either traced as 'extra' and added to 'pinned_vm'
or trace as 'user_extra' and added to 'locked_vm'. This applies for
normal trace buffers and auxiliary trace buffer.
However in function perf_mmap_close() all auxiliary trace buffer is
subtraced from 'locked_vm' and never from 'pinned_vm'. This breaks the
ballance.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: gor@linux.ibm.com
Cc: hechaol@fb.com
Cc: heiko.carstens@de.ibm.com
Cc: linux-perf-users@vger.kernel.org
Cc: songliubraving@fb.com
Fixes: d44248a413 ("perf/core: Rework memory accounting in perf_mmap()")
Link: https://lkml.kernel.org/r/20191021083354.67868-1-tmricht@linux.ibm.com
[ Minor readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Introduce frequency QoS, based on the "raw" low-level PM QoS, to
represent min and max frequency requests and aggregate constraints.
The min and max frequency requests are to be represented by
struct freq_qos_request objects and the aggregate constraints are to
be represented by struct freq_constraints objects. The latter are
expected to be initialized with the help of freq_constraints_init().
The freq_qos_read_value() helper is defined to retrieve the aggregate
constraints values from a given struct freq_constraints object and
there are the freq_qos_add_request(), freq_qos_update_request() and
freq_qos_remove_request() helpers to manipulate the min and max
frequency requests. It is assumed that the the helpers will not
run concurrently with each other for the same struct freq_qos_request
object, so if that may be the case, their uses must ensure proper
synchronization between them (e.g. through locking).
In addition, freq_qos_add_notifier() and freq_qos_remove_notifier()
are provided to add and remove notifiers that will trigger on aggregate
constraint changes to and from a given struct freq_constraints object,
respectively.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Pull more Kbuild fixes from Masahiro Yamada:
- fix a bashism of setlocalversion
- do not use the too new --sort option of tar
* tag 'kbuild-fixes-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kheaders: substituting --sort in archive creation
scripts: setlocalversion: fix a bashism
kbuild: update comment about KBUILD_ALLDIRS
Pull hrtimer fixlet from Thomas Gleixner:
"A single commit annotating the lockcless access to timer->base with
READ_ONCE() and adding the WRITE_ONCE() counterparts for completeness"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
hrtimer: Annotate lockless access to timer->base
Pull stop-machine fix from Thomas Gleixner:
"A single fix, amending stop machine with WRITE/READ_ONCE() to address
the fallout of KCSAN"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
stop_machine: Avoid potential race behaviour
Attaching uprobe to text section in THP splits the PMD mapped page table
into PTE mapped entries. On uprobe detach, we would like to regroup PMD
mapped page table entry to regain performance benefit of THP.
However, the regroup is broken For perf_event based trace_uprobe. This
is because perf_event based trace_uprobe calls uprobe_unregister twice
on close: first in TRACE_REG_PERF_CLOSE, then in
TRACE_REG_PERF_UNREGISTER. The second call will split the PMD mapped
page table entry, which is not the desired behavior.
Fix this by only use FOLL_SPLIT_PMD for uprobe register case.
Add a WARN() to confirm uprobe unregister never work on huge pages, and
abort the operation when this WARN() triggers.
Link: http://lkml.kernel.org/r/20191017164223.2762148-6-songliubraving@fb.com
Fixes: 5a52c9df62 ("uprobe: use FOLL_SPLIT_PMD instead of FOLL_SPLIT")
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In the format of synthetic events, the "gfp_t" is shown as "signed:1",
but in fact the "gfp_t" is "unsigned", should be shown as "signed:0".
The issue can be reproduced by the following commands:
echo 'memlatency u64 lat; unsigned int order; gfp_t gfp_flags; int migratetype' > /sys/kernel/debug/tracing/synthetic_events
cat /sys/kernel/debug/tracing/events/synthetic/memlatency/format
name: memlatency
ID: 2233
format:
field:unsigned short common_type; offset:0; size:2; signed:0;
field:unsigned char common_flags; offset:2; size:1; signed:0;
field:unsigned char common_preempt_count; offset:3; size:1; signed:0;
field:int common_pid; offset:4; size:4; signed:1;
field:u64 lat; offset:8; size:8; signed:0;
field:unsigned int order; offset:16; size:4; signed:0;
field:gfp_t gfp_flags; offset:24; size:4; signed:1;
field:int migratetype; offset:32; size:4; signed:1;
print fmt: "lat=%llu, order=%u, gfp_flags=%x, migratetype=%d", REC->lat, REC->order, REC->gfp_flags, REC->migratetype
Link: http://lkml.kernel.org/r/20191018012034.6404-1-zhengjun.xing@linux.intel.com
Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull power management fixes from Rafael Wysocki:
"These include a fix for a recent regression in the ACPI CPU
performance scaling code, a PCI device power management fix,
a system shutdown fix related to cpufreq, a removal of an ACPI
suspend-to-idle blacklist entry and a build warning fix.
Specifics:
- Fix possible NULL pointer dereference in the ACPI processor scaling
initialization code introduced by a recent cpufreq update (Rafael
Wysocki).
- Fix possible deadlock due to suspending cpufreq too late during
system shutdown (Rafael Wysocki).
- Make the PCI device system resume code path be more consistent with
its PM-runtime counterpart to fix an issue with missing delay on
transitions from D3cold to D0 during system resume from
suspend-to-idle on some systems (Rafael Wysocki).
- Drop Dell XPS13 9360 from the LPS0 Idle _DSM blacklist to make it
use suspend-to-idle by default (Mario Limonciello).
- Fix build warning in the core system suspend support code (Ben
Dooks)"
* tag 'pm-5.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: processor: Avoid NULL pointer dereferences at init time
PCI: PM: Fix pci_power_up()
PM: sleep: include <linux/pm_runtime.h> for pm_wq
cpufreq: Avoid cpufreq_suspend() deadlock on system shutdown
ACPI: PM: Drop Dell XPS13 9360 from LPS0 Idle _DSM blacklist
* pm-cpufreq:
ACPI: processor: Avoid NULL pointer dereferences at init time
cpufreq: Avoid cpufreq_suspend() deadlock on system shutdown
* pm-sleep:
PM: sleep: include <linux/pm_runtime.h> for pm_wq
ACPI: PM: Drop Dell XPS13 9360 from LPS0 Idle _DSM blacklist
Introduce new helper that reuses existing skb perf_event output
implementation, but can be called from raw_tracepoint programs
that receive 'struct sk_buff *' as tracepoint argument or
can walk other kernel data structures to skb pointer.
In order to do that teach verifier to resolve true C types
of bpf helpers into in-kernel BTF ids.
The type of kernel pointer passed by raw tracepoint into bpf
program will be tracked by the verifier all the way until
it's passed into helper function.
For example:
kfree_skb() kernel function calls trace_kfree_skb(skb, loc);
bpf programs receives that skb pointer and may eventually
pass it into bpf_skb_output() bpf helper which in-kernel is
implemented via bpf_skb_event_output() kernel function.
Its first argument in the kernel is 'struct sk_buff *'.
The verifier makes sure that types match all the way.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-11-ast@kernel.org
Pointer to BTF object is a pointer to kernel object or NULL.
Such pointers can only be used by BPF_LDX instructions.
The verifier changed their opcode from LDX|MEM|size
to LDX|PROBE_MEM|size to make JITing easier.
The number of entries in extable is the number of BPF_LDX insns
that access kernel memory via "pointer to BTF type".
Only these load instructions can fault.
Since x86 extable is relative it has to be allocated in the same
memory region as JITed code.
Allocate it prior to last pass of JITing and let the last pass populate it.
Pointer to extable in bpf_prog_aux is necessary to make page fault
handling fast.
Page fault handling is done in two steps:
1. bpf_prog_kallsyms_find() finds BPF program that page faulted.
It's done by walking rb tree.
2. then extable for given bpf program is binary searched.
This process is similar to how page faulting is done for kernel modules.
The exception handler skips over faulting x86 instruction and
initializes destination register with zero. This mimics exact
behavior of bpf_probe_read (when probe_kernel_read faults dest is zeroed).
JITs for other architectures can add support in similar way.
Until then they will reject unknown opcode and fallback to interpreter.
Since extable should be aligned and placed near JITed code
make bpf_jit_binary_alloc() return 4 byte aligned image offset,
so that extable aligning formula in bpf_int_jit_compile() doesn't need
to rely on internal implementation of bpf_jit_binary_alloc().
On x86 gcc defaults to 16-byte alignment for regular kernel functions
due to better performance. JITed code may be aligned to 16 in the future,
but it will use 4 in the meantime.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-10-ast@kernel.org
libbpf analyzes bpf C program, searches in-kernel BTF for given type name
and stores it into expected_attach_type.
The kernel verifier expects this btf_id to point to something like:
typedef void (*btf_trace_kfree_skb)(void *, struct sk_buff *skb, void *loc);
which represents signature of raw_tracepoint "kfree_skb".
Then btf_ctx_access() matches ctx+0 access in bpf program with 'skb'
and 'ctx+8' access with 'loc' arguments of "kfree_skb" tracepoint.
In first case it passes btf_id of 'struct sk_buff *' back to the verifier core
and 'void *' in second case.
Then the verifier tracks PTR_TO_BTF_ID as any other pointer type.
Like PTR_TO_SOCKET points to 'struct bpf_sock',
PTR_TO_TCP_SOCK points to 'struct bpf_tcp_sock', and so on.
PTR_TO_BTF_ID points to in-kernel structs.
If 1234 is btf_id of 'struct sk_buff' in vmlinux's BTF
then PTR_TO_BTF_ID#1234 points to one of in kernel skbs.
When PTR_TO_BTF_ID#1234 is dereferenced (like r2 = *(u64 *)r1 + 32)
the btf_struct_access() checks which field of 'struct sk_buff' is
at offset 32. Checks that size of access matches type definition
of the field and continues to track the dereferenced type.
If that field was a pointer to 'struct net_device' the r2's type
will be PTR_TO_BTF_ID#456. Where 456 is btf_id of 'struct net_device'
in vmlinux's BTF.
Such verifier analysis prevents "cheating" in BPF C program.
The program cannot cast arbitrary pointer to 'struct sk_buff *'
and access it. C compiler would allow type cast, of course,
but the verifier will notice type mismatch based on BPF assembly
and in-kernel BTF.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-7-ast@kernel.org
Add attach_btf_id attribute to prog_load command.
It's similar to existing expected_attach_type attribute which is
used in several cgroup based program types.
Unfortunately expected_attach_type is ignored for
tracing programs and cannot be reused for new purpose.
Hence introduce attach_btf_id to verify bpf programs against
given in-kernel BTF type id at load time.
It is strictly checked to be valid for raw_tp programs only.
In a later patches it will become:
btf_id == 0 semantics of existing raw_tp progs.
btd_id > 0 raw_tp with BTF and additional type safety.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-5-ast@kernel.org
If in-kernel BTF exists parse it and prepare 'struct btf *btf_vmlinux'
for further use by the verifier.
In-kernel BTF is trusted just like kallsyms and other build artifacts
embedded into vmlinux.
Yet run this BTF image through BTF verifier to make sure
that it is valid and it wasn't mangled during the build.
If in-kernel BTF is incorrect it means either gcc or pahole or kernel
are buggy. In such case disallow loading BPF programs.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-4-ast@kernel.org
Both multi_cpu_stop() and set_state() access multi_stop_data::state
racily using plain accesses. These are subject to compiler
transformations which could break the intended behaviour of the code,
and this situation is detected by KCSAN on both arm64 and x86 (splats
below).
Improve matters by using READ_ONCE() and WRITE_ONCE() to ensure that the
compiler cannot elide, replay, or tear loads and stores.
In multi_cpu_stop() the two loads of multi_stop_data::state are expected to
be a consistent value, so snapshot the value into a temporary variable to
ensure this.
The state transitions are serialized by atomic manipulation of
multi_stop_data::num_threads, and other fields in multi_stop_data are not
modified while subject to concurrent reads.
KCSAN splat on arm64:
| BUG: KCSAN: data-race in multi_cpu_stop+0xa8/0x198 and set_state+0x80/0xb0
|
| write to 0xffff00001003bd00 of 4 bytes by task 24 on cpu 3:
| set_state+0x80/0xb0
| multi_cpu_stop+0x16c/0x198
| cpu_stopper_thread+0x170/0x298
| smpboot_thread_fn+0x40c/0x560
| kthread+0x1a8/0x1b0
| ret_from_fork+0x10/0x18
|
| read to 0xffff00001003bd00 of 4 bytes by task 14 on cpu 1:
| multi_cpu_stop+0xa8/0x198
| cpu_stopper_thread+0x170/0x298
| smpboot_thread_fn+0x40c/0x560
| kthread+0x1a8/0x1b0
| ret_from_fork+0x10/0x18
|
| Reported by Kernel Concurrency Sanitizer on:
| CPU: 1 PID: 14 Comm: migration/1 Not tainted 5.3.0-00007-g67ab35a199f4-dirty #3
| Hardware name: linux,dummy-virt (DT)
KCSAN splat on x86:
| write to 0xffffb0bac0013e18 of 4 bytes by task 19 on cpu 2:
| set_state kernel/stop_machine.c:170 [inline]
| ack_state kernel/stop_machine.c:177 [inline]
| multi_cpu_stop+0x1a4/0x220 kernel/stop_machine.c:227
| cpu_stopper_thread+0x19e/0x280 kernel/stop_machine.c:516
| smpboot_thread_fn+0x1a8/0x300 kernel/smpboot.c:165
| kthread+0x1b5/0x200 kernel/kthread.c:255
| ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352
|
| read to 0xffffb0bac0013e18 of 4 bytes by task 44 on cpu 7:
| multi_cpu_stop+0xb4/0x220 kernel/stop_machine.c:213
| cpu_stopper_thread+0x19e/0x280 kernel/stop_machine.c:516
| smpboot_thread_fn+0x1a8/0x300 kernel/smpboot.c:165
| kthread+0x1b5/0x200 kernel/kthread.c:255
| ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352
|
| Reported by Kernel Concurrency Sanitizer on:
| CPU: 7 PID: 44 Comm: migration/7 Not tainted 5.3.0+ #1
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20191007104536.27276-1-mark.rutland@arm.com
The option --sort=ORDER was only introduced in tar 1.28 (2014), which
is rather new and might not be available in some setups.
This patch tries to replicate the previous behaviour as closely as
possible to fix the kheaders build for older environments. It does
not produce identical archives compared to the previous version due
to minor sorting differences but produces reproducible results itself
in my tests.
Reported-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Dmitry Goldin <dgoldin+lkml@protonmail.ch>
Tested-by: Andreas Schwab <schwab@suse.de>
Tested-by: Quentin Perret <qperret@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
bpf stackmap with build-id lookup (BPF_F_STACK_BUILD_ID) can trigger A-A
deadlock on rq_lock():
rcu: INFO: rcu_sched detected stalls on CPUs/tasks:
[...]
Call Trace:
try_to_wake_up+0x1ad/0x590
wake_up_q+0x54/0x80
rwsem_wake+0x8a/0xb0
bpf_get_stack+0x13c/0x150
bpf_prog_fbdaf42eded9fe46_on_event+0x5e3/0x1000
bpf_overflow_handler+0x60/0x100
__perf_event_overflow+0x4f/0xf0
perf_swevent_overflow+0x99/0xc0
___perf_sw_event+0xe7/0x120
__schedule+0x47d/0x620
schedule+0x29/0x90
futex_wait_queue_me+0xb9/0x110
futex_wait+0x139/0x230
do_futex+0x2ac/0xa50
__x64_sys_futex+0x13c/0x180
do_syscall_64+0x42/0x100
entry_SYSCALL_64_after_hwframe+0x44/0xa9
This can be reproduced by:
1. Start a multi-thread program that does parallel mmap() and malloc();
2. taskset the program to 2 CPUs;
3. Attach bpf program to trace_sched_switch and gather stackmap with
build-id, e.g. with trace.py from bcc tools:
trace.py -U -p <pid> -s <some-bin,some-lib> t:sched:sched_switch
A sample reproducer is attached at the end.
This could also trigger deadlock with other locks that are nested with
rq_lock.
Fix this by checking whether irqs are disabled. Since rq_lock and all
other nested locks are irq safe, it is safe to do up_read() when irqs are
not disable. If the irqs are disabled, postpone up_read() in irq_work.
Fixes: 615755a77b ("bpf: extend stackmap to save binary_build_id+offset instead of address")
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191014171223.357174-1-songliubraving@fb.com
Reproducer:
============================ 8< ============================
char *filename;
void *worker(void *p)
{
void *ptr;
int fd;
char *pptr;
fd = open(filename, O_RDONLY);
if (fd < 0)
return NULL;
while (1) {
struct timespec ts = {0, 1000 + rand() % 2000};
ptr = mmap(NULL, 4096 * 64, PROT_READ, MAP_PRIVATE, fd, 0);
usleep(1);
if (ptr == MAP_FAILED) {
printf("failed to mmap\n");
break;
}
munmap(ptr, 4096 * 64);
usleep(1);
pptr = malloc(1);
usleep(1);
pptr[0] = 1;
usleep(1);
free(pptr);
usleep(1);
nanosleep(&ts, NULL);
}
close(fd);
return NULL;
}
int main(int argc, char *argv[])
{
void *ptr;
int i;
pthread_t threads[THREAD_COUNT];
if (argc < 2)
return 0;
filename = argv[1];
for (i = 0; i < THREAD_COUNT; i++) {
if (pthread_create(threads + i, NULL, worker, NULL)) {
fprintf(stderr, "Error creating thread\n");
return 0;
}
}
for (i = 0; i < THREAD_COUNT; i++)
pthread_join(threads[i], NULL);
return 0;
}
============================ 8< ============================
The __kthread_queue_delayed_work is not exported so
make it static, to avoid the following sparse warning:
kernel/kthread.c:869:6: warning: symbol '__kthread_queue_delayed_work' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull parisc fixes from Helge Deller:
- Fix a parisc-specific fallout of Christoph's
dma_set_mask_and_coherent() patches (Sven)
- Fix a vmap memory leak in ioremap()/ioremap() (Helge)
- Some minor cleanups and documentation updates (Nick, Helge)
* 'parisc-5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Remove 32-bit DMA enforcement from sba_iommu
parisc: Fix vmap memory leak in ioremap()/iounmap()
parisc: prefer __section from compiler_attributes.h
parisc: sysctl.c: Use CONFIG_PARISC instead of __hppa_ define
MAINTAINERS: Add hp_sdc drivers to parisc arch
Alexei Starovoitov says:
====================
pull-request: bpf-next 2019-10-14
The following pull-request contains BPF updates for your *net-next* tree.
12 days of development and
85 files changed, 1889 insertions(+), 1020 deletions(-)
The main changes are:
1) auto-generation of bpf_helper_defs.h, from Andrii.
2) split of bpf_helpers.h into bpf_{helpers, helper_defs, endian, tracing}.h
and move into libbpf, from Andrii.
3) Track contents of read-only maps as scalars in the verifier, from Andrii.
4) small x86 JIT optimization, from Daniel.
5) cross compilation support, from Ivan.
6) bpf flow_dissector enhancements, from Jakub and Stanislav.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Followup to commit dd2261ed45 ("hrtimer: Protect lockless access
to timer->base")
lock_hrtimer_base() fetches timer->base without lock exclusion.
Compiler is allowed to read timer->base twice (even if considered dumb)
which could end up trying to lock migration_base and return
&migration_base.
base = timer->base;
if (likely(base != &migration_base)) {
/* compiler reads timer->base again, and now (base == &migration_base)
raw_spin_lock_irqsave(&base->cpu_base->lock, *flags);
if (likely(base == timer->base))
return base; /* == &migration_base ! */
Similarly the write sides must use WRITE_ONCE() to avoid store tearing.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191008173204.180879-1-edumazet@google.com
Pull tracing fixes from Steven Rostedt:
"A few tracing fixes:
- Remove lockdown from tracefs itself and moved it to the trace
directory. Have the open functions there do the lockdown checks.
- Fix a few races with opening an instance file and the instance
being deleted (Discovered during the lockdown updates). Kept
separate from the clean up code such that they can be backported to
stable easier.
- Clean up and consolidated the checks done when opening a trace
file, as there were multiple checks that need to be done, and it
did not make sense having them done in each open instance.
- Fix a regression in the record mcount code.
- Small hw_lat detector tracer fixes.
- A trace_pipe read fix due to not initializing trace_seq"
* tag 'trace-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Initialize iter->seq after zeroing in tracing_read_pipe()
tracing/hwlat: Don't ignore outer-loop duration when calculating max_latency
tracing/hwlat: Report total time spent in all NMIs during the sample
recordmcount: Fix nop_mcount() function
tracing: Do not create tracefs files if tracefs lockdown is in effect
tracing: Add locked_down checks to the open calls of files created for tracefs
tracing: Add tracing_check_open_get_tr()
tracing: Have trace events system open call tracing_open_generic_tr()
tracing: Get trace_array reference for available_tracers files
ftrace: Get a reference counter for the trace_array on filter files
tracefs: Revert ccbd54ff54 ("tracefs: Restrict tracefs when the kernel is locked down")
A customer reported the following softlockup:
[899688.160002] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [test.sh:16464]
[899688.160002] CPU: 0 PID: 16464 Comm: test.sh Not tainted 4.12.14-6.23-azure #1 SLE12-SP4
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] Kernel panic - not syncing: softlockup: hung tasks
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] RSP: 0018:ffffa86784d4fde8 EFLAGS: 00000257 ORIG_RAX: ffffffffffffff12
[899688.160002] RAX: ffffffff970fea00 RBX: 0000000000000001 RCX: 0000000000000000
[899688.160002] RDX: ffffffff00000001 RSI: 0000000000000080 RDI: ffffffff970fea00
[899688.160002] RBP: ffffffffffffffff R08: ffffffffffffffff R09: 0000000000000000
[899688.160002] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8b59014720d8
[899688.160002] R13: ffff8b59014720c0 R14: ffff8b5901471090 R15: ffff8b5901470000
[899688.160002] tracing_read_pipe+0x336/0x3c0
[899688.160002] __vfs_read+0x26/0x140
[899688.160002] vfs_read+0x87/0x130
[899688.160002] SyS_read+0x42/0x90
[899688.160002] do_syscall_64+0x74/0x160
It caught the process in the middle of trace_access_unlock(). There is
no loop. So, it must be looping in the caller tracing_read_pipe()
via the "waitagain" label.
Crashdump analyze uncovered that iter->seq was completely zeroed
at this point, including iter->seq.seq.size. It means that
print_trace_line() was never able to print anything and
there was no forward progress.
The culprit seems to be in the code:
/* reset all but tr, trace, and overruns */
memset(&iter->seq, 0,
sizeof(struct trace_iterator) -
offsetof(struct trace_iterator, seq));
It was added by the commit 53d0aa7730 ("ftrace:
add logic to record overruns"). It was v2.6.27-rc1.
It was the time when iter->seq looked like:
struct trace_seq {
unsigned char buffer[PAGE_SIZE];
unsigned int len;
};
There was no "size" variable and zeroing was perfectly fine.
The solution is to reinitialize the structure after or without
zeroing.
Link: http://lkml.kernel.org/r/20191011142134.11997-1-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
