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Merge tag 'selinux-pr-20200416' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux
Pull SELinux fix from Paul Moore:
"One small SELinux fix to ensure we cleanup properly on an error
condition"
* tag 'selinux-pr-20200416' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: free str on error in str_read()
for invalid pointer dereference and uninitialized variable use on
asynchronous create and unlink error paths.
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Merge tag 'ceph-for-5.7-rc2' of git://github.com/ceph/ceph-client
Pull ceph fixes from Ilya Dryomov:
- a set of patches for a deadlock on "rbd map" error path
- a fix for invalid pointer dereference and uninitialized variable use
on asynchronous create and unlink error paths.
* tag 'ceph-for-5.7-rc2' of git://github.com/ceph/ceph-client:
ceph: fix potential bad pointer deref in async dirops cb's
rbd: don't mess with a page vector in rbd_notify_op_lock()
rbd: don't test rbd_dev->opts in rbd_dev_image_release()
rbd: call rbd_dev_unprobe() after unwatching and flushing notifies
rbd: avoid a deadlock on header_rwsem when flushing notifies
A dump_stack call for signature related errors can be too noisy
and not of much value in debugging such problems.
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Shyam Prasad N <nspmangalore@gmail.com>
snapshot trigger. On a slow machine, the trigger can occur before the
snapshot is allocated causing a warning to be displayed in the ring buffer,
and no snapshot triggering. Reversing the allocation and the enabling of the
trigger fixes the problem.
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Merge tag 'trace-v5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"This fixes a small race between allocating a snapshot buffer and
setting the snapshot trigger.
On a slow machine, the trigger can occur before the snapshot is
allocated causing a warning to be displayed in the ring buffer, and no
snapshot triggering. Reversing the allocation and the enabling of the
trigger fixes the problem"
* tag 'trace-v5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix the race between registering 'snapshot' event trigger and triggering 'snapshot' operation
If seq_file .next function does not change position index,
read after some lseek can generate unexpected output:
$ dd if=/proc/keys bs=1 # full usual output
0f6bfdf5 I--Q--- 2 perm 3f010000 1000 1000 user 4af2f79ab8848d0a: 740
1fb91b32 I--Q--- 3 perm 1f3f0000 1000 65534 keyring _uid.1000: 2
27589480 I--Q--- 1 perm 0b0b0000 0 0 user invocation_id: 16
2f33ab67 I--Q--- 152 perm 3f030000 0 0 keyring _ses: 2
33f1d8fa I--Q--- 4 perm 3f030000 1000 1000 keyring _ses: 1
3d427fda I--Q--- 2 perm 3f010000 1000 1000 user 69ec44aec7678e5a: 740
3ead4096 I--Q--- 1 perm 1f3f0000 1000 65534 keyring _uid_ses.1000: 1
521+0 records in
521+0 records out
521 bytes copied, 0,00123769 s, 421 kB/s
But a read after lseek in middle of last line results in the partial
last line and then a repeat of the final line:
$ dd if=/proc/keys bs=500 skip=1
dd: /proc/keys: cannot skip to specified offset
g _uid_ses.1000: 1
3ead4096 I--Q--- 1 perm 1f3f0000 1000 65534 keyring _uid_ses.1000: 1
0+1 records in
0+1 records out
97 bytes copied, 0,000135035 s, 718 kB/s
and a read after lseek beyond end of file results in the last line being
shown:
$ dd if=/proc/keys bs=1000 skip=1 # read after lseek beyond end of file
dd: /proc/keys: cannot skip to specified offset
3ead4096 I--Q--- 1 perm 1f3f0000 1000 65534 keyring _uid_ses.1000: 1
0+1 records in
0+1 records out
76 bytes copied, 0,000119981 s, 633 kB/s
See https://bugzilla.kernel.org/show_bug.cgi?id=206283
Fixes: 1f4aace60b ("fs/seq_file.c: simplify seq_file iteration code ...")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add Intel Comet Lake PCH-U PCI ID to the list of supported controllers.
Set default SATA LPM so the SoC can enter S0ix.
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the inode dirty data flushing to a workqueue so that multiple
threads can take advantage of a single thread's flushing work. The
ratelimiting technique used in bdd4ee4 was not successful, because
threads that skipped the inode flush scan due to ratelimiting would
ENOSPC early, which caused occasional (but noticeable) changes in
behavior and sporadic fstest regressions.
Therefore, make all the writer threads wait on a single inode flush,
which eliminates both the stampeding hordes of flushers and the small
window in which a write could fail with ENOSPC because it lost the
ratelimit race after even another thread freed space.
Fixes: c6425702f2 ("xfs: ratelimit inode flush on buffered write ENOSPC")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
If in blk_mq_dispatch_rq_list() we find no budget, then we break of the
dispatch loop, but the request may keep the driver tag, evaulated
in 'nxt' in the previous loop iteration.
Fix by putting the driver tag for that request.
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For reporting purposes, an evsel sample can have a callchain synthesized
from AUX area data. Add support for keeping track of synthesized sample
types. Note, the recorded sample_type cannot be changed because it is
needed to continue to parse events.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-11-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Using 'type' variable for checking for callchains is equivalent to using
evsel__has_callchain(evsel) and is how the other PERF_SAMPLE_ bits are checked
in this function, so use it to be consistent.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-11-adrian.hunter@intel.com
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a thread stack function to create a call chain for hardware events
where the sample records get created some time after the event occurred.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-10-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently, callchains can be synthesized only for synthesized events. Add
an itrace option to synthesize callchains for regular events.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-9-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add ->evsel_is_auxtrace() callback to identify if a selected event
is an AUX area event.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kim Phillips <kim.phillips@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200401101613.6201-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This script works in tandem with d3-flame-graph to generate flame graphs
from perf. It supports two output formats: JSON and HTML (the default).
The HTML format will look for a standalone d3-flame-graph template file
in /usr/share/d3-flame-graph/d3-flamegraph-base.html and fill in the
collected stacks.
Usage:
perf record -a -g -F 99 sleep 60
perf script report flamegraph
Combined:
perf script flamegraph -a -F 99 sleep 60
Committer testing:
Tested both with "PYTHON=python3" and with the default, that uses
python2-devel:
Complete set of instructions:
$ mkdir /tmp/build/perf
$ make PYTHON=python3 -C tools/perf O=/tmp/build/perf install-bin
$ export PATH=~/bin:$PATH
$ perf record -a -g -F 99 sleep 60
$ perf script report flamegraph
Now go and open the generated flamegraph.html file in a browser.
At first this required building with PYTHON=python3, but after I
reported this Andreas was kind enough to send a patch making it work
with both python and python3.
Signed-off-by: Andreas Gerstmayr <agerstmayr@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brendan Gregg <bgregg@netflix.com>
Cc: Martin Spier <mspier@netflix.com>
Link: http://lore.kernel.org/lkml/20200320151355.66302-1-agerstmayr@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch refactors metricgroup__add_metric function where some part of
it move to function metricgroup__add_metric_param. No logic change.
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lore.kernel.org/lkml/20200401203340.31402-4-kjain@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add the expr_scanner_ctx object to hold user data for the expr scanner.
Currently it holds only start_token, Kajol Jain will use it to hold 24x7
runtime param.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lore.kernel.org/lkml/20200401203340.31402-3-kjain@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Adding expr_ prefix for parse_ctx and parse_id, to straighten out the
expr* namespace.
There's no functional change.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lore.kernel.org/lkml/20200401203340.31402-2-kjain@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Reuse an existing char buffer to avoid two PATH_MAX sized char buffers.
Reduces stack frame sizes by 4kb.
perf_event__synthesize_mmap_events before 'sub $0x45b8,%rsp' after
'sub $0x35b8,%rsp'.
perf_event__get_comm_ids before 'sub $0x2028,%rsp' after
'sub $0x1028,%rsp'.
The performance impact of this change is negligible.
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrey Zhizhikin <andrey.z@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20200402154357.107873-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The xxx_mountpoint() interface provided by fs.c finds mount points for
common pseudo filesystems. The first time xxx_mountpoint() is invoked,
it scans the mount table (/proc/mounts) looking for a match. If found,
it is cached. The price to scan /proc/mounts is paid once if the mount
is found.
When the mount point is not found, subsequent calls to xxx_mountpoint()
scan /proc/mounts over and over again. There is no caching.
This causes a scaling issue in perf record with hugeltbfs__mountpoint().
The function is called for each process found in
synthesize__mmap_events(). If the machine has thousands of processes
and if the /proc/mounts has many entries this could cause major overhead
in perf record. We have observed multi-second slowdowns on some
configurations.
As an example on a laptop:
Before:
$ sudo umount /dev/hugepages
$ strace -e trace=openat -o /tmp/tt perf record -a ls
$ fgrep mounts /tmp/tt
285
After:
$ sudo umount /dev/hugepages
$ strace -e trace=openat -o /tmp/tt perf record -a ls
$ fgrep mounts /tmp/tt
1
One could argue that the non-caching in case the moint point is not
found is intentional. That way subsequent calls may discover a moint
point if the sysadmin mounts the filesystem. But the same argument could
be made against caching the mount point. It could be unmounted causing
errors. It all depends on the intent of the interface. This patch
assumes it is expected to scan /proc/mounts once. The patch documents
the caching behavior in the fs.h header file.
An alternative would be to just fix perf record. But it would solve the
problem with hugetlbs__mountpoint() but there could be similar issues
(possibly down the line) with other xxx_mountpoint() calls in perf or
other tools.
Signed-off-by: Stephane Eranian <eranian@google.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrey Zhizhikin <andrey.z@gmail.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20200402154357.107873-3-irogers@google.com
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Event synthesis may occur at the start or end (tail) of a perf command.
In system-wide mode it can scan every process in /proc, which may add
seconds of latency before event recording. Add a new benchmark that
times how long event synthesis takes with and without data synthesis.
An example execution looks like:
$ perf bench internals synthesize
# Running 'internals/synthesize' benchmark:
Average synthesis took: 168.253800 usec
Average data synthesis took: 208.104700 usec
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrey Zhizhikin <andrey.z@gmail.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20200402154357.107873-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Update the kernel.rst documentation file with the information related to
usage of CAP_PERFMON capability to secure performance monitoring and
observability operations in system.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/84c32383-14a2-fa35-16b6-f9e59bd37240@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Update perf-security.rst documentation file with the information
related to usage of CAP_PERFMON capability to secure performance
monitoring and observability operations in system.
Committer notes:
While testing 'perf top' under cap_perfmon I noticed that it needs
some more capability and Alexey pointed out cap_ipc_lock, as needed by
this kernel chunk:
kernel/events/core.c: 6101
if ((locked > lock_limit) && perf_is_paranoid() &&
!capable(CAP_IPC_LOCK)) {
ret = -EPERM;
goto unlock;
}
So I added it to the documentation, and also mentioned that if the
libcap version doesn't yet supports 'cap_perfmon', its numeric value can
be used instead, i.e. if:
# setcap "cap_perfmon,cap_ipc_lock,cap_sys_ptrace,cap_syslog=ep" perf
Fails, try:
# setcap "38,cap_ipc_lock,cap_sys_ptrace,cap_syslog=ep" perf
I also added a paragraph stating that using an unpatched libcap will
fail the check for CAP_PERFMON, as it checks the cap number against a
maximum to see if it is valid, which makes it use as the default the
'cycles:u' event, even tho a cap_perfmon capable perf binary can get
kernel samples, to workaround that just use, e.g.:
# perf top -e cycles
# perf record -e cycles
And it will sample kernel and user modes.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/17278551-9399-9ebe-d665-8827016a217d@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Open access to monitoring for CAP_PERFMON privileged process. Providing
the access under CAP_PERFMON capability singly, without the rest of
CAP_SYS_ADMIN credentials, excludes chances to misuse the credentials
and makes operation more secure.
CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)
For backward compatibility reasons access to the monitoring remains open
for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure monitoring is discouraged with respect to CAP_PERFMON capability.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/691f1096-b15f-9b12-50a0-c2b93918149e@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Open access to monitoring for CAP_PERFMON privileged process. Providing
the access under CAP_PERFMON capability singly, without the rest of
CAP_SYS_ADMIN credentials, excludes chances to misuse the credentials
and makes operation more secure.
CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)
For backward compatibility reasons access to the monitoring remains open
for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure monitoring is discouraged with respect to CAP_PERFMON capability.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/4ec1d6f7-548c-8d1c-f84a-cebeb9674e4e@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Open access to monitoring for CAP_PERFMON privileged process. Providing
the access under CAP_PERFMON capability singly, without the rest of
CAP_SYS_ADMIN credentials, excludes chances to misuse the credentials
and makes operation more secure.
CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)
For backward compatibility reasons access to the monitoring remains open
for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure monitoring is discouraged with respect to CAP_PERFMON capability.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Helge Deller <deller@gmx.de>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/8cc98809-d35b-de0f-de02-4cf554f3cf62@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Open access to monitoring for CAP_PERFMON privileged process. Providing
the access under CAP_PERFMON capability singly, without the rest of
CAP_SYS_ADMIN credentials, excludes chances to misuse the credentials
and makes operation more secure.
CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)
For backward compatibility reasons access to the monitoring remains open
for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure monitoring is discouraged with respect to CAP_PERFMON capability.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/ac98cd9f-b59e-673c-c70d-180b3e7695d2@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Open access to bpf_trace monitoring for CAP_PERFMON privileged process.
Providing the access under CAP_PERFMON capability singly, without the
rest of CAP_SYS_ADMIN credentials, excludes chances to misuse the
credentials and makes operation more secure.
CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)
For backward compatibility reasons access to bpf_trace monitoring
remains open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN
usage for secure bpf_trace monitoring is discouraged with respect to
CAP_PERFMON capability.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/c0a0ae47-8b6e-ff3e-416b-3cd1faaf71c0@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Open access to i915_perf monitoring for CAP_PERFMON privileged process.
Providing the access under CAP_PERFMON capability singly, without the
rest of CAP_SYS_ADMIN credentials, excludes chances to misuse the
credentials and makes operation more secure.
CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)
For backward compatibility reasons access to i915_events subsystem remains
open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure i915_events monitoring is discouraged with respect to CAP_PERFMON
capability.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/e3e3292f-f765-ea98-e59c-fbe2db93fd34@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Extend error messages to mention CAP_PERFMON capability as an option to
substitute CAP_SYS_ADMIN capability for secure system performance
monitoring and observability operations. Make
perf_event_paranoid_check() and __cmd_ftrace() to be aware of
CAP_PERFMON capability.
CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)
For backward compatibility reasons access to perf_events subsystem remains
open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure perf_events monitoring is discouraged with respect to CAP_PERFMON
capability.
Committer testing:
Using a libcap with this patch:
diff --git a/libcap/include/uapi/linux/capability.h b/libcap/include/uapi/linux/capability.h
index 78b2fd4c8a95..89b5b0279b60 100644
--- a/libcap/include/uapi/linux/capability.h
+++ b/libcap/include/uapi/linux/capability.h
@@ -366,8 +366,9 @@ struct vfs_ns_cap_data {
#define CAP_AUDIT_READ 37
+#define CAP_PERFMON 38
-#define CAP_LAST_CAP CAP_AUDIT_READ
+#define CAP_LAST_CAP CAP_PERFMON
#define cap_valid(x) ((x) >= 0 && (x) <= CAP_LAST_CAP)
Note that using '38' in place of 'cap_perfmon' works to some degree with
an old libcap, its only when cap_get_flag() is called that libcap
performs an error check based on the maximum value known for
capabilities that it will fail.
This makes determining the default of perf_event_attr.exclude_kernel to
fail, as it can't determine if CAP_PERFMON is in place.
Using 'perf top -e cycles' avoids the default check and sets
perf_event_attr.exclude_kernel to 1.
As root, with a libcap supporting CAP_PERFMON:
# groupadd perf_users
# adduser perf -g perf_users
# mkdir ~perf/bin
# cp ~acme/bin/perf ~perf/bin/
# chgrp perf_users ~perf/bin/perf
# setcap "cap_perfmon,cap_sys_ptrace,cap_syslog=ep" ~perf/bin/perf
# getcap ~perf/bin/perf
/home/perf/bin/perf = cap_sys_ptrace,cap_syslog,cap_perfmon+ep
# ls -la ~perf/bin/perf
-rwxr-xr-x. 1 root perf_users 16968552 Apr 9 13:10 /home/perf/bin/perf
As the 'perf' user in the 'perf_users' group:
$ perf top -a --stdio
Error:
Failed to mmap with 1 (Operation not permitted)
$
Either add the cap_ipc_lock capability to the perf binary or reduce the
ring buffer size to some smaller value:
$ perf top -m10 -a --stdio
rounding mmap pages size to 64K (16 pages)
Error:
Failed to mmap with 1 (Operation not permitted)
$ perf top -m4 -a --stdio
Error:
Failed to mmap with 1 (Operation not permitted)
$ perf top -m2 -a --stdio
PerfTop: 762 irqs/sec kernel:49.7% exact: 100.0% lost: 0/0 drop: 0/0 [4000Hz cycles], (all, 4 CPUs)
------------------------------------------------------------------------------------------------------
9.83% perf [.] __symbols__insert
8.58% perf [.] rb_next
5.91% [kernel] [k] module_get_kallsym
5.66% [kernel] [k] kallsyms_expand_symbol.constprop.0
3.98% libc-2.29.so [.] __GI_____strtoull_l_internal
3.66% perf [.] rb_insert_color
2.34% [kernel] [k] vsnprintf
2.30% [kernel] [k] string_nocheck
2.16% libc-2.29.so [.] _IO_getdelim
2.15% [kernel] [k] number
2.13% [kernel] [k] format_decode
1.58% libc-2.29.so [.] _IO_feof
1.52% libc-2.29.so [.] __strcmp_avx2
1.50% perf [.] rb_set_parent_color
1.47% libc-2.29.so [.] __libc_calloc
1.24% [kernel] [k] do_syscall_64
1.17% [kernel] [k] __x86_indirect_thunk_rax
$ perf record -a sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.552 MB perf.data (74 samples) ]
$ perf evlist
cycles
$ perf evlist -v
cycles: size: 120, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|CPU|PERIOD, read_format: ID, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1, precise_ip: 3, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1
$ perf report | head -20
# To display the perf.data header info, please use --header/--header-only options.
#
#
# Total Lost Samples: 0
#
# Samples: 74 of event 'cycles'
# Event count (approx.): 15694834
#
# Overhead Command Shared Object Symbol
# ........ ............... .......................... ......................................
#
19.62% perf [kernel.vmlinux] [k] strnlen_user
13.88% swapper [kernel.vmlinux] [k] intel_idle
13.83% ksoftirqd/0 [kernel.vmlinux] [k] pfifo_fast_dequeue
13.51% swapper [kernel.vmlinux] [k] kmem_cache_free
6.31% gnome-shell [kernel.vmlinux] [k] kmem_cache_free
5.66% kworker/u8:3+ix [kernel.vmlinux] [k] delay_tsc
4.42% perf [kernel.vmlinux] [k] __set_cpus_allowed_ptr
3.45% kworker/2:1-eve [kernel.vmlinux] [k] shmem_truncate_range
2.29% gnome-shell libgobject-2.0.so.0.6000.7 [.] g_closure_ref
$
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/a66d5648-2b8e-577e-e1f2-1d56c017ab5e@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Open access to monitoring via kprobes and uprobes and eBPF tracing for
CAP_PERFMON privileged process. Providing the access under CAP_PERFMON
capability singly, without the rest of CAP_SYS_ADMIN credentials,
excludes chances to misuse the credentials and makes operation more
secure.
perf kprobes and uprobes are used by ftrace and eBPF. perf probe uses
ftrace to define new kprobe events, and those events are treated as
tracepoint events. eBPF defines new probes via perf_event_open interface
and then the probes are used in eBPF tracing.
CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)
For backward compatibility reasons access to perf_events subsystem
remains open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN
usage for secure perf_events monitoring is discouraged with respect to
CAP_PERFMON capability.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Cc: linux-man@vger.kernel.org
Link: http://lore.kernel.org/lkml/3c129d9a-ba8a-3483-ecc5-ad6c8e7c203f@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Open access to monitoring of kernel code, CPUs, tracepoints and
namespaces data for a CAP_PERFMON privileged process. Providing the
access under CAP_PERFMON capability singly, without the rest of
CAP_SYS_ADMIN credentials, excludes chances to misuse the credentials
and makes operation more secure.
CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)
For backward compatibility reasons the access to perf_events subsystem
remains open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN
usage for secure perf_events monitoring is discouraged with respect to
CAP_PERFMON capability.
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: linux-man@vger.kernel.org
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/471acaef-bb8a-5ce2-923f-90606b78eef9@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Introduce the CAP_PERFMON capability designed to secure system
performance monitoring and observability operations so that CAP_PERFMON
can assist CAP_SYS_ADMIN capability in its governing role for
performance monitoring and observability subsystems.
CAP_PERFMON hardens system security and integrity during performance
monitoring and observability operations by decreasing attack surface that
is available to a CAP_SYS_ADMIN privileged process [2]. Providing the access
to system performance monitoring and observability operations under CAP_PERFMON
capability singly, without the rest of CAP_SYS_ADMIN credentials, excludes
chances to misuse the credentials and makes the operation more secure.
Thus, CAP_PERFMON implements the principle of least privilege for
performance monitoring and observability operations (POSIX IEEE 1003.1e:
2.2.2.39 principle of least privilege: A security design principle that
states that a process or program be granted only those privileges
(e.g., capabilities) necessary to accomplish its legitimate function,
and only for the time that such privileges are actually required)
CAP_PERFMON meets the demand to secure system performance monitoring and
observability operations for adoption in security sensitive, restricted,
multiuser production environments (e.g. HPC clusters, cloud and virtual compute
environments), where root or CAP_SYS_ADMIN credentials are not available to
mass users of a system, and securely unblocks applicability and scalability
of system performance monitoring and observability operations beyond root
and CAP_SYS_ADMIN use cases.
CAP_PERFMON takes over CAP_SYS_ADMIN credentials related to system performance
monitoring and observability operations and balances amount of CAP_SYS_ADMIN
credentials following the recommendations in the capabilities man page [1]
for CAP_SYS_ADMIN: "Note: this capability is overloaded; see Notes to kernel
developers, below." For backward compatibility reasons access to system
performance monitoring and observability subsystems of the kernel remains
open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN capability
usage for secure system performance monitoring and observability operations
is discouraged with respect to the designed CAP_PERFMON capability.
Although the software running under CAP_PERFMON can not ensure avoidance
of related hardware issues, the software can still mitigate these issues
following the official hardware issues mitigation procedure [2]. The bugs
in the software itself can be fixed following the standard kernel development
process [3] to maintain and harden security of system performance monitoring
and observability operations.
[1] http://man7.org/linux/man-pages/man7/capabilities.7.html
[2] https://www.kernel.org/doc/html/latest/process/embargoed-hardware-issues.html
[3] https://www.kernel.org/doc/html/latest/admin-guide/security-bugs.html
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/5590d543-82c6-490a-6544-08e6a5517db0@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add the DSO_BINARY_TYPE__BPF_IMAGE dso binary type to recognize BPF
images that carry trampoline or dispatcher.
Upcoming patches will add support to read the image data, store it
within the BPF feature in perf.data and display it for annotation
purposes.
Currently we only display following message:
# ./perf annotate bpf_trampoline_24456 --stdio
Percent | Source code & Disassembly of . for cycles (504 ...
--------------------------------------------------------------- ...
: to be implemented
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@redhat.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jesper Dangaard Brouer <hawk@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200312195610.346362-16-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There's no special load action for ksymbol data on map__load/dso__load
action, where the kernel is getting loaded. It only gets confused with
kernel kallsyms/vmlinux load for bpf object, which fails and could mess
up with the map.
Disabling any further load of the map for ksymbol related dso/map.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@redhat.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jesper Dangaard Brouer <hawk@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200312195610.346362-15-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Synthesize bpf images (trampolines/dispatchers) on start, as ksymbol
events from /proc/kallsyms. Having this perf can recognize samples from
those images and perf report and top shows them correctly.
The rest of the ksymbol handling is already in place from for the bpf
programs monitoring, so only the initial state was needed.
perf report output:
# Overhead Command Shared Object Symbol
12.37% test_progs [kernel.vmlinux] [k] entry_SYSCALL_64
11.80% test_progs [kernel.vmlinux] [k] syscall_return_via_sysret
9.63% test_progs bpf_prog_bcf7977d3b93787c_prog2 [k] bpf_prog_bcf7977d3b93787c_prog2
6.90% test_progs bpf_trampoline_24456 [k] bpf_trampoline_24456
6.36% test_progs [kernel.vmlinux] [k] memcpy_erms
Committer notes:
Use scnprintf() instead of strncpy() to overcome this on fedora:32,
rawhide and OpenMandriva Cooker:
CC /tmp/build/perf/util/bpf-event.o
In file included from /usr/include/string.h:495,
from /git/linux/tools/lib/bpf/libbpf_common.h:12,
from /git/linux/tools/lib/bpf/bpf.h:31,
from util/bpf-event.c:4:
In function 'strncpy',
inlined from 'process_bpf_image' at util/bpf-event.c:323:2,
inlined from 'kallsyms_process_symbol' at util/bpf-event.c:358:9:
/usr/include/bits/string_fortified.h:106:10: error: '__builtin_strncpy' specified bound 256 equals destination size [-Werror=stringop-truncation]
106 | return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Björn Töpel <bjorn.topel@intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@redhat.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Jesper Dangaard Brouer <hawk@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200312195610.346362-14-jolsa@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
When --timeout is used and a workload is specified to be started by
'perf stat', i.e.
$ perf stat --timeout 1000 sleep 1h
The --timeout wasn't being honoured, i.e. the workload, 'sleep 1h' in
the above example, should be terminated after 1000ms, but it wasn't,
'perf stat' was waiting for it to finish.
Fix it by sending a SIGTERM when the timeout expires.
Now it works:
# perf stat -e cycles --timeout 1234 sleep 1h
sleep: Terminated
Performance counter stats for 'sleep 1h':
1,066,692 cycles
1.234314838 seconds time elapsed
0.000750000 seconds user
0.000000000 seconds sys
#
Fixes: f1f8ad52f8 ("perf stat: Add support to print counts after a period of time")
Reported-by: Konstantin Kharlamov <hi-angel@yandex.ru>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=207243
Tested-by: Konstantin Kharlamov <hi-angel@yandex.ru>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: yuzhoujian <yuzhoujian@didichuxing.com>
Link: https://lore.kernel.org/lkml/20200415153803.GB20324@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Michael Kerrisk suggested to replace numeric clock IDs with symbolic names.
Now the content of these files looks like this:
$ cat /proc/774/timens_offsets
monotonic 864000 0
boottime 1728000 0
For setting offsets, both representations of clocks (numeric and symbolic)
can be used.
As for compatibility, it is acceptable to change things as long as
userspace doesn't care. The format of timens_offsets files is very new and
there are no userspace tools yet which rely on this format.
But three projects crun, util-linux and criu rely on the interface of
setting time offsets and this is why it's required to continue supporting
the numeric clock IDs on write.
Fixes: 04a8682a71 ("fs/proc: Introduce /proc/pid/timens_offsets")
Suggested-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200411154031.642557-1-avagin@gmail.com
Although the vSGIs are not directly visible to the host, they still
get moved around by the CPU hotplug, for example. This results in
the kernel moaning on the console, such as:
genirq: irq_chip GICv4.1-sgi did not update eff. affinity mask of irq 38
Updating the effective affinity on set_affinity() fixes it.
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
When a vPE is made resident, the GIC starts parsing the virtual pending
table to deliver pending interrupts. This takes place asynchronously,
and can at times take a long while. Long enough that the vcpu enters
the guest and hits WFI before any interrupt has been signaled yet.
The vcpu then exits, blocks, and now gets a doorbell. Rince, repeat.
In order to avoid the above, a (optional on GICv4, mandatory on v4.1)
feature allows the GIC to feedback to the hypervisor whether it is
done parsing the VPT by clearing the GICR_VPENDBASER.Dirty bit.
The hypervisor can then wait until the GIC is ready before actually
running the vPE.
Plug the detection code as well as polling on vPE schedule. While
at it, tidy-up the kernel message that displays the GICv4 optional
features.
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
perf stat:
Jin Yao:
- Fix no metric header if --per-socket and --metric-only set
build system:
- Fix python building when built with clang, that was failing if the clang
version doesn't support -fno-semantic-interposition.
tools UAPI headers:
Arnaldo Carvalho de Melo:
- Update various copies of kernel headers, some ended up automatically
updating build-time generated tables to enable tools such as 'perf trace'
to decode syscalls and tracepoints arguments.
Now the tools/perf build is free of UAPI drift warnings.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-urgent-for-mingo-5.7-20200414' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
perf stat:
Jin Yao:
- Fix no metric header if --per-socket and --metric-only set
build system:
- Fix python building when built with clang, that was failing if the clang
version doesn't support -fno-semantic-interposition.
tools UAPI headers:
Arnaldo Carvalho de Melo:
- Update various copies of kernel headers, some ended up automatically
updating build-time generated tables to enable tools such as 'perf trace'
to decode syscalls and tracepoints arguments.
Now the tools/perf build is free of UAPI drift warnings.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
ASB was failing to load on Turing GPUs when firmware is being loaded
from initramfs, leaving the GPU in an odd state and causing suspend/
resume to fail.
Add missing MODULE_FIRMWARE() lines for initramfs generators.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Cc: <stable@vger.kernel.org> # 5.6
