[ Upstream commit b26a124cbfa80f42bfc4e63e1d5643ca98159d66 ]
Add 'symstr' type for storing the kernel symbol as a string data
instead of the symbol address. This allows us to filter the
events by wildcard symbol name.
e.g.
# echo 'e:wqfunc workqueue.workqueue_execute_start symname=$function:symstr' >> dynamic_events
# cat events/eprobes/wqfunc/format
name: wqfunc
ID: 2110
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:__data_loc char[] symname; offset:8; size:4; signed:1;
print fmt: " symname=\"%s\"", __get_str(symname)
Note that there is already 'symbol' type which just change the
print format (so it still stores the symbol address in the tracing
ring buffer.) On the other hand, 'symstr' type stores the actual
"symbol+offset/size" data as a string.
Link: https://lore.kernel.org/all/166679930847.1528100.4124308529180235965.stgit@devnote3/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Stable-dep-of: 66bcf65d6cf0 ("tracing/probes: Fix to avoid double count of the string length on the array")
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ed5a7047d2011cb6b2bf84ceb6680124cc6a7d95 upstream.
Currently setgid stripping in file_remove_privs()'s should_remove_suid()
helper is inconsistent with other parts of the vfs. Specifically, it only
raises ATTR_KILL_SGID if the inode is S_ISGID and S_IXGRP but not if the
inode isn't in the caller's groups and the caller isn't privileged over the
inode although we require this already in setattr_prepare() and
setattr_copy() and so all filesystem implement this requirement implicitly
because they have to use setattr_{prepare,copy}() anyway.
But the inconsistency shows up in setgid stripping bugs for overlayfs in
xfstests (e.g., generic/673, generic/683, generic/685, generic/686,
generic/687). For example, we test whether suid and setgid stripping works
correctly when performing various write-like operations as an unprivileged
user (fallocate, reflink, write, etc.):
echo "Test 1 - qa_user, non-exec file $verb"
setup_testfile
chmod a+rws $junk_file
commit_and_check "$qa_user" "$verb" 64k 64k
The test basically creates a file with 6666 permissions. While the file has
the S_ISUID and S_ISGID bits set it does not have the S_IXGRP set. On a
regular filesystem like xfs what will happen is:
sys_fallocate()
-> vfs_fallocate()
-> xfs_file_fallocate()
-> file_modified()
-> __file_remove_privs()
-> dentry_needs_remove_privs()
-> should_remove_suid()
-> __remove_privs()
newattrs.ia_valid = ATTR_FORCE | kill;
-> notify_change()
-> setattr_copy()
In should_remove_suid() we can see that ATTR_KILL_SUID is raised
unconditionally because the file in the test has S_ISUID set.
But we also see that ATTR_KILL_SGID won't be set because while the file
is S_ISGID it is not S_IXGRP (see above) which is a condition for
ATTR_KILL_SGID being raised.
So by the time we call notify_change() we have attr->ia_valid set to
ATTR_KILL_SUID | ATTR_FORCE. Now notify_change() sees that
ATTR_KILL_SUID is set and does:
ia_valid = attr->ia_valid |= ATTR_MODE
attr->ia_mode = (inode->i_mode & ~S_ISUID);
which means that when we call setattr_copy() later we will definitely
update inode->i_mode. Note that attr->ia_mode still contains S_ISGID.
Now we call into the filesystem's ->setattr() inode operation which will
end up calling setattr_copy(). Since ATTR_MODE is set we will hit:
if (ia_valid & ATTR_MODE) {
umode_t mode = attr->ia_mode;
vfsgid_t vfsgid = i_gid_into_vfsgid(mnt_userns, inode);
if (!vfsgid_in_group_p(vfsgid) &&
!capable_wrt_inode_uidgid(mnt_userns, inode, CAP_FSETID))
mode &= ~S_ISGID;
inode->i_mode = mode;
}
and since the caller in the test is neither capable nor in the group of the
inode the S_ISGID bit is stripped.
But assume the file isn't suid then ATTR_KILL_SUID won't be raised which
has the consequence that neither the setgid nor the suid bits are stripped
even though it should be stripped because the inode isn't in the caller's
groups and the caller isn't privileged over the inode.
If overlayfs is in the mix things become a bit more complicated and the bug
shows up more clearly. When e.g., ovl_setattr() is hit from
ovl_fallocate()'s call to file_remove_privs() then ATTR_KILL_SUID and
ATTR_KILL_SGID might be raised but because the check in notify_change() is
questioning the ATTR_KILL_SGID flag again by requiring S_IXGRP for it to be
stripped the S_ISGID bit isn't removed even though it should be stripped:
sys_fallocate()
-> vfs_fallocate()
-> ovl_fallocate()
-> file_remove_privs()
-> dentry_needs_remove_privs()
-> should_remove_suid()
-> __remove_privs()
newattrs.ia_valid = ATTR_FORCE | kill;
-> notify_change()
-> ovl_setattr()
// TAKE ON MOUNTER'S CREDS
-> ovl_do_notify_change()
-> notify_change()
// GIVE UP MOUNTER'S CREDS
// TAKE ON MOUNTER'S CREDS
-> vfs_fallocate()
-> xfs_file_fallocate()
-> file_modified()
-> __file_remove_privs()
-> dentry_needs_remove_privs()
-> should_remove_suid()
-> __remove_privs()
newattrs.ia_valid = attr_force | kill;
-> notify_change()
The fix for all of this is to make file_remove_privs()'s
should_remove_suid() helper to perform the same checks as we already
require in setattr_prepare() and setattr_copy() and have notify_change()
not pointlessly requiring S_IXGRP again. It doesn't make any sense in the
first place because the caller must calculate the flags via
should_remove_suid() anyway which would raise ATTR_KILL_SGID.
While we're at it we move should_remove_suid() from inode.c to attr.c
where it belongs with the rest of the iattr helpers. Especially since it
returns ATTR_KILL_S{G,U}ID flags. We also rename it to
setattr_should_drop_suidgid() to better reflect that it indicates both
setuid and setgid bit removal and also that it returns attr flags.
Running xfstests with this doesn't report any regressions. We should really
try and use consistent checks.
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3b7ddab8a19aefc768f345fd3782af35b4a68d9b ]
Default value of maxactive is set as num_possible_cpus() for nonpreemptable
systems. For a 2-core system, only 2 kretprobe instances would be allocated
in default, then these 2 instances for execve kretprobe are very likely to
be used up with a pipelined command.
Here's the testcase: a shell script was added to crontab, and the content
of the script is:
#!/bin/sh
do_something_magic `tr -dc a-z < /dev/urandom | head -c 10`
cron will trigger a series of program executions (4 times every hour). Then
events loss would be noticed normally after 3-4 hours of testings.
The issue is caused by a burst of series of execve requests. The best number
of kretprobe instances could be different case by case, and should be user's
duty to determine, but num_possible_cpus() as the default value is inadequate
especially for systems with small number of cpus.
This patch enables the logic for preemption as default, thus increases the
minimum of maxactive to 10 for nonpreemptable systems.
Link: https://lore.kernel.org/all/20221110081502.492289-1-wuqiang.matt@bytedance.com/
Signed-off-by: wuqiang <wuqiang.matt@bytedance.com>
Reviewed-by: Solar Designer <solar@openwall.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Pull documentation fixes from Jonathan Corbet:
"A handful of relatively simple documentation fixes, plus a set of
patches catching the Chinese translation up with the front-page
rework"
* tag 'docs-6.1-2' of git://git.lwn.net/linux:
Documentation: rtla: Correct command line example
docs/zh_CN: add a man-pages link to zh_CN/index.rst
docs/zh_CN: Rewrite the Chinese translation front page
docs/zh_CN: add zh_CN/arch.rst
docs/zh_CN: promote the title of zh_CN/process/index.rst
docs/zh_CN: Update the translation of page_owner to 6.0-rc7
docs/zh_CN: Update the translation of ksm to 6.0-rc7
docs/howto: Replace abundoned URL of gmane.org
Documentation: ubifs: Fix compression idiom
Documentation/mm/page_owner.rst: delete frequently changing experimental data
docs/zh_CN: Fix build warning
docs: ftrace: Correct access mode
Pull perf tools updates from Arnaldo Carvalho de Melo:
- Add support for AMD on 'perf mem' and 'perf c2c', the kernel
enablement patches went via tip.
Example:
$ sudo perf mem record -- -c 10000
^C[ perf record: Woken up 227 times to write data ]
[ perf record: Captured and wrote 58.760 MB perf.data (836978 samples) ]
$ sudo perf mem report -F mem,sample,snoop
Samples: 836K of event 'ibs_op//', Event count (approx.): 8418762
Memory access Samples Snoop
N/A 700620 N/A
L1 hit 126675 N/A
L2 hit 424 N/A
L3 hit 664 HitM
L3 hit 10 N/A
Local RAM hit 2 N/A
Remote RAM (1 hop) hit 8558 N/A
Remote Cache (1 hop) hit 3 N/A
Remote Cache (1 hop) hit 2 HitM
Remote Cache (2 hops) hit 10 HitM
Remote Cache (2 hops) hit 6 N/A
Uncached hit 4 N/A
$
- "perf lock" improvements:
- Add -E/--entries option to limit the number of entries to
display, say to ask for just the top 5 contended locks.
- Add -q/--quiet option to suppress header and debug messages.
- Add a 'perf test' kernel lock contention entry to test 'perf
lock'.
- "perf lock contention" improvements:
- Ask BPF's bpf_get_stackid() to skip some callchain entries.
The ones closer to the tooling are bpf related and not that
interesting, the ones calling the locking function are the ones
we're interested in, example of a full, unskipped callstack:
- Allow changing the callstack depth and number of entries to skip.
1 10.74 us 10.74 us 10.74 us spinlock __bpf_trace_contention_begin+0xb
0xffffffffc03b5c47 bpf_prog_bf07ae9e2cbd02c5_contention_begin+0x117
0xffffffffc03b5c47 bpf_prog_bf07ae9e2cbd02c5_contention_begin+0x117
0xffffffffbb8b8e75 bpf_trace_run2+0x35
0xffffffffbb7eab9b __bpf_trace_contention_begin+0xb
0xffffffffbb7ebe75 queued_spin_lock_slowpath+0x1f5
0xffffffffbc1c26ff _raw_spin_lock+0x1f
0xffffffffbb841015 tick_do_update_jiffies64+0x25
0xffffffffbb8409ee tick_irq_enter+0x9e
- Show full callstack in verbose mode (-v option), sometimes this
is desirable instead of showing just one callstack entry.
- Allow multiple time ranges in 'perf record --delay' to help in
reducing the amount of data collected from hardware tracing (Intel
PT, etc) when there is a rough idea of periods of time where events
of interest take time.
- Add Intel PT to record only decoder debug messages when error
happens.
- Improve layout of Intel PT man page.
- Add new branch types: alignment, data and inst faults and arch
specific ones, such as fiq, debug_halt, debug_exit, debug_inst and
debug_data on arm64.
Kernel enablement went thru the tip tree.
- Fix 'perf probe' error log check in 'perf test' when no debuginfo is
available.
- Fix 'perf stat' aggregation mode logic, it should be looking at the
CPU not at the core number.
- Fix flags parsing in 'perf trace' filters.
- Introduce compact encoding of CPU range encoding on perf.data, to
avoid having a bitmap with all the CPUs.
- Improvements to the 'perf stat' metrics, including adding
"core_wide", and computing "smt" from the CPU topology.
- Add support to the new PERF_FORMAT_LOST perf_event_attr.read_format,
that allows tooling to ask for the precise number of lost samples for
a given event.
- Add 'addr' sort key to see just the address of sampled instructions:
$ perf record -o- true | perf report -i- -s addr
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.000 MB - ]
# Samples: 12 of event 'cycles:u'
# Event count (approx.): 252512
#
# Overhead Address
# ........ ..................
42.96% 0x7f96f08443d7
29.55% 0x7f96f0859b50
14.76% 0x7f96f0852e02
8.30% 0x7f96f0855028
4.43% 0xffffffff8de01087
perf annotate: Toggle full address <-> offset display
- Add 'f' hotkey to the 'perf annotate' TUI interface when in
'disassembler output' mode ('o' hotkey) to toggle showing full
virtual address or just the offset.
- Cache DSO build-ids when synthesizing PERF_RECORD_MMAP records for
pre-existing threads, at the start of a 'perf record' session,
speeding up that record startup phase.
- Add a command line option to specify build ids in 'perf inject'.
- Update JSON event files for the Intel alderlake, broadwell,
broadwellde, broadwellx, cascadelakex, haswell, haswellx, icelake,
icelakex, ivybridge, ivytown, jaketown, sandybridge, sapphirerapids,
skylake, skylakex, and tigerlake processors.
- Update vendor JSON event files for the ARM Neoverse V1 and E1
platforms.
- Add a 'perf test' entry for 'perf mem' where a struct has false
sharing and this gets detected in the 'perf mem' output, tested with
Intel, AMD and ARM64 systems.
- Add a 'perf test' entry to test the resolution of java symbols, where
an output like this is expected:
8.18% jshell jitted-50116-29.so [.] Interpreter
0.75% Thread-1 jitted-83602-1670.so [.] jdk.internal.jimage.BasicImageReader.getString(int)
- Add tests for the ARM64 CoreSight hardware tracing feature, with
specially crafted pureloop, memcpy, thread loop and unroll tread that
then gets traced and the output compared with expected output.
Documentation explaining it is also included.
- Add per thread Intel PT 'perf test' entry to check that
PERF_RECORD_TEXT_POKE events are recorded per CPU, resulting in a
mixture of per thread and per CPU events and mmaps, verify that this
gets all recorded correctly.
- Introduce pthread mutex wrappers to allow for building with clang's
-Wthread-safety, i.e. using the "guarded_by" "pt_guarded_by"
"lockable", "exclusive_lock_function", "exclusive_trylock_function",
"exclusive_locks_required", and "no_thread_safety_analysis" compiler
function attributes.
- Fix empty version number when building outside of a git repo.
- Improve feature detection display when multiple versions of a feature
are present, such as for binutils libbfd, that has a mix of possible
ways to detect according to the Linux distribution.
Previously in some cases we had:
Auto-detecting system features
<SNIP>
... libbfd: [ on ]
... libbfd-liberty: [ on ]
... libbfd-liberty-z: [ on ]
<SNIP>
Now for this case we show just the main feature:
Auto-detecting system features
<SNIP>
... libbfd: [ on ]
<SNIP>
- Remove some unused structs, variables, macros, function prototypes
and includes from various places.
* tag 'perf-tools-for-v6.1-1-2022-10-07' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (169 commits)
perf script: Add missing fields in usage hint
perf mem: Print "LFB/MAB" for PERF_MEM_LVLNUM_LFB
perf mem/c2c: Avoid printing empty lines for unsupported events
perf mem/c2c: Add load store event mappings for AMD
perf mem/c2c: Set PERF_SAMPLE_WEIGHT for LOAD_STORE events
perf mem: Add support for printing PERF_MEM_LVLNUM_{CXL|IO}
perf amd ibs: Sync arch/x86/include/asm/amd-ibs.h header with the kernel
tools headers UAPI: Sync include/uapi/linux/perf_event.h header with the kernel
perf stat: Fix cpu check to use id.cpu.cpu in aggr_printout()
perf test coresight: Add relevant documentation about ARM64 CoreSight testing
perf test: Add git ignore for tmp and output files of ARM CoreSight tests
perf test coresight: Add unroll thread test shell script
perf test coresight: Add unroll thread test tool
perf test coresight: Add thread loop test shell scripts
perf test coresight: Add thread loop test tool
perf test coresight: Add memcpy thread test shell script
perf test coresight: Add memcpy thread test tool
perf test: Add git ignore for perf data generated by the ARM CoreSight tests
perf test: Add arm64 asm pureloop test shell script
perf test: Add asm pureloop test tool
...
Pull tracing updates from Steven Rostedt:
"Major changes:
- Changed location of tracing repo from personal git repo to:
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git
- Added Masami Hiramatsu as co-maintainer
- Updated MAINTAINERS file to separate out FTRACE as it is more than
just TRACING.
Minor changes:
- Added Mark Rutland as FTRACE reviewer
- Updated user_events to make it on its way to remove the BROKEN tag.
The changes should now be acceptable but will run it through a
cycle and hopefully we can remove the BROKEN tag next release.
- Added filtering to eprobes
- Added a delta time to the benchmark trace event
- Have the histogram and filter callbacks called via a switch
statement instead of indirect functions. This speeds it up to avoid
retpolines.
- Add a way to wake up ring buffer waiters waiting for the ring
buffer to fill up to its watermark.
- New ioctl() on the trace_pipe_raw file to wake up ring buffer
waiters.
- Wake up waiters when the ring buffer is disabled. A reader may
block when the ring buffer is disabled, but if it was blocked when
the ring buffer is disabled it should then wake up.
Fixes:
- Allow splice to read partially read ring buffer pages. This fixes
splice never moving forward.
- Fix inverted compare that made the "shortest" ring buffer wait
queue actually the longest.
- Fix a race in the ring buffer between resetting a page when a
writer goes to another page, and the reader.
- Fix ftrace accounting bug when function hooks are added at boot up
before the weak functions are set to "disabled".
- Fix bug that freed a user allocated snapshot buffer when enabling a
tracer.
- Fix possible recursive locks in osnoise tracer
- Fix recursive locking direct functions
- Other minor clean ups and fixes"
* tag 'trace-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (44 commits)
ftrace: Create separate entry in MAINTAINERS for function hooks
tracing: Update MAINTAINERS to reflect new tracing git repo
tracing: Do not free snapshot if tracer is on cmdline
ftrace: Still disable enabled records marked as disabled
tracing/user_events: Move pages/locks into groups to prepare for namespaces
tracing: Add Masami Hiramatsu as co-maintainer
tracing: Remove unused variable 'dups'
MAINTAINERS: add myself as a tracing reviewer
ring-buffer: Fix race between reset page and reading page
tracing/user_events: Update ABI documentation to align to bits vs bytes
tracing/user_events: Use bits vs bytes for enabled status page data
tracing/user_events: Use refcount instead of atomic for ref tracking
tracing/user_events: Ensure user provided strings are safely formatted
tracing/user_events: Use WRITE instead of READ for io vector import
tracing/user_events: Use NULL for strstr checks
tracing: Fix spelling mistake "preapre" -> "prepare"
tracing: Wake up waiters when tracing is disabled
tracing: Add ioctl() to force ring buffer waiters to wake up
tracing: Wake up ring buffer waiters on closing of the file
ring-buffer: Add ring_buffer_wake_waiters()
...
Pull char/misc and other driver updates from Greg KH:
"Here is the large set of char/misc and other small driver subsystem
changes for 6.1-rc1. Loads of different things in here:
- IIO driver updates, additions, and changes. Probably the largest
part of the diffstat
- habanalabs driver update with support for new hardware and
features, the second largest part of the diff.
- fpga subsystem driver updates and additions
- mhi subsystem updates
- Coresight driver updates
- gnss subsystem updates
- extcon driver updates
- icc subsystem updates
- fsi subsystem updates
- nvmem subsystem and driver updates
- misc driver updates
- speakup driver additions for new features
- lots of tiny driver updates and cleanups
All of these have been in the linux-next tree for a while with no
reported issues"
* tag 'char-misc-6.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (411 commits)
w1: Split memcpy() of struct cn_msg flexible array
spmi: pmic-arb: increase SPMI transaction timeout delay
spmi: pmic-arb: block access for invalid PMIC arbiter v5 SPMI writes
spmi: pmic-arb: correct duplicate APID to PPID mapping logic
spmi: pmic-arb: add support to dispatch interrupt based on IRQ status
spmi: pmic-arb: check apid against limits before calling irq handler
spmi: pmic-arb: do not ack and clear peripheral interrupts in cleanup_irq
spmi: pmic-arb: handle spurious interrupt
spmi: pmic-arb: add a print in cleanup_irq
drivers: spmi: Directly use ida_alloc()/free()
MAINTAINERS: add TI ECAP driver info
counter: ti-ecap-capture: capture driver support for ECAP
Documentation: ABI: sysfs-bus-counter: add frequency & num_overflows items
dt-bindings: counter: add ti,am62-ecap-capture.yaml
counter: Introduce the COUNTER_COMP_ARRAY component type
counter: Consolidate Counter extension sysfs attribute creation
counter: Introduce the Count capture component
counter: 104-quad-8: Add Signal polarity component
counter: Introduce the Signal polarity component
counter: interrupt-cnt: Implement watch_validate callback
...
Pull tracing updates from Steven Rostedt:
- Runtime verification infrastructure
This is the biggest change here. It introduces the runtime
verification that is necessary for running Linux on safety critical
systems.
It allows for deterministic automata models to be inserted into the
kernel that will attach to tracepoints, where the information on
these tracepoints will move the model from state to state.
If a state is encountered that does not belong to the model, it will
then activate a given reactor, that could just inform the user or
even panic the kernel (for which safety critical systems will detect
and can recover from).
- Two monitor models are also added: Wakeup In Preemptive (WIP - not to
be confused with "work in progress"), and Wakeup While Not Running
(WWNR).
- Added __vstring() helper to the TRACE_EVENT() macro to replace
several vsnprintf() usages that were all doing it wrong.
- eprobes now can have their event autogenerated when the event name is
left off.
- The rest is various cleanups and fixes.
* tag 'trace-v6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (50 commits)
rv: Unlock on error path in rv_unregister_reactor()
tracing: Use alignof__(struct {type b;}) instead of offsetof()
tracing/eprobe: Show syntax error logs in error_log file
scripts/tracing: Fix typo 'the the' in comment
tracepoints: It is CONFIG_TRACEPOINTS not CONFIG_TRACEPOINT
tracing: Use free_trace_buffer() in allocate_trace_buffers()
tracing: Use a struct alignof to determine trace event field alignment
rv/reactor: Add the panic reactor
rv/reactor: Add the printk reactor
rv/monitor: Add the wwnr monitor
rv/monitor: Add the wip monitor
rv/monitor: Add the wip monitor skeleton created by dot2k
Documentation/rv: Add deterministic automata instrumentation documentation
Documentation/rv: Add deterministic automata monitor synthesis documentation
tools/rv: Add dot2k
Documentation/rv: Add deterministic automaton documentation
tools/rv: Add dot2c
Documentation/rv: Add a basic documentation
rv/include: Add instrumentation helper functions
rv/include: Add deterministic automata monitor definition via C macros
...
Currently when creating a specific group of trace events,
take kprobe event as example, the user must use the following format:
p:GRP/EVENT [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS],
which means user must enter EVENT name, one example is:
echo 'p:usb_gadget/config_usb_cfg_link config_usb_cfg_link $arg1' >> kprobe_events
It is not simple if there are too many entries because the event name is
the same as symbol name.
This change allows user to specify no EVENT name, format changed as:
p:GRP/ [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS]
It will generate event name automatically and one example is:
echo 'p:usb_gadget/ config_usb_cfg_link $arg1' >> kprobe_events.
Link: https://lore.kernel.org/all/1656296348-16111-4-git-send-email-quic_linyyuan@quicinc.com/
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
