Lets add test cases to cover really all possible direct packet
access tests for good/bad access cases so we keep tracking them.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NJohn Fastabend <john.fastabend@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The skb->mark field is a union with reserved_tailroom which is used
in the TCP code paths from stream memory allocation. Allowing SK_SKB
programs to set this field creates a conflict with future code
optimizations, such as "gifting" the skb to the egress path instead
of creating a new skb and doing a memcpy.

Because we do not have a released version of SK_SKB yet lets just
remove it for now. A more appropriate scratch pad to use at the
socket layer is dev_scratch, but lets add that in future kernels
when needed.
Signed-off-by: NJohn Fastabend <john.fastabend@gmail.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

SK_SKB BPF programs are run from the socket/tcp context but early in
the stack before much of the TCP metadata is needed in tcp_skb_cb. So
we can use some unused fields to place BPF metadata needed for SK_SKB
programs when implementing the redirect function.

This allows us to drop the preempt disable logic. It does however
require an API change so sk_redirect_map() has been updated to
additionally provide ctx_ptr to skb. Note, we do however continue to
disable/enable preemption around actual BPF program running to account
for map updates.
Signed-off-by: NJohn Fastabend <john.fastabend@gmail.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Only TCP sockets have been tested and at the moment the state change
callback only handles TCP sockets. This adds a check to ensure that
sockets actually being added are TCP sockets.

For net-next we can consider UDP support.
Signed-off-by: NJohn Fastabend <john.fastabend@gmail.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit f1174f77 ("bpf/verifier: rework value tracking")
removed the crafty selection of which pointer types are
allowed to be modified.  This is OK for most pointer types
since adjust_ptr_min_max_vals() will catch operations on
immutable pointers.  One exception is PTR_TO_CTX which is
now allowed to be offseted freely.

The intent of aforementioned commit was to allow context
access via modified registers.  The offset passed to
->is_valid_access() verifier callback has been adjusted
by the value of the variable offset.

What is missing, however, is taking the variable offset
into account when the context register is used.  Or in terms
of the code adding the offset to the value passed to the
->convert_ctx_access() callback.  This leads to the following
eBPF user code:

     r1 += 68
     r0 = *(u32 *)(r1 + 8)
     exit

being translated to this in kernel space:

   0: (07) r1 += 68
   1: (61) r0 = *(u32 *)(r1 +180)
   2: (95) exit

Offset 8 is corresponding to 180 in the kernel, but offset
76 is valid too.  Verifier will "accept" access to offset
68+8=76 but then "convert" access to offset 8 as 180.
Effective access to offset 248 is beyond the kernel context.
(This is a __sk_buff example on a debug-heavy kernel -
packet mark is 8 -> 180, 76 would be data.)

Dereferencing the modified context pointer is not as easy
as dereferencing other types, because we have to translate
the access to reading a field in kernel structures which is
usually at a different offset and often of a different size.
To allow modifying the pointer we would have to make sure
that given eBPF instruction will always access the same
field or the fields accessed are "compatible" in terms of
offset and size...

Disallow dereferencing modified context pointers and add
to selftests the test case described here.

Fixes: f1174f77 ("bpf/verifier: rework value tracking")
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NEdward Cree <ecree@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit c91fc851.

That change caused a C6 and PC6 residency regression on large idle systems.

Users also complained about new output indicating jitter:

turbostat: cpu6 jitter 3794 9142
Signed-off-by: NLen Brown <len.brown@intel.com>
Cc: 4.13+ <stable@vger.kernel.org> # v4.13+
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

I was stress testing some backports and with high load, after some time,
the latest version of the selftest showed some false positive in
connection with the uffdio_copy_retry.  This seems to fix it while still
exercising -EEXIST in the background transfer once in a while.

The fork child will quit after the last UFFDIO_COPY is run, so a
repeated UFFDIO_COPY may not return -EEXIST.  This change restricts the
-EEXIST stress to the background transfer where the memory can't go away
from under it.

Also updated uffdio_zeropage, so the interface is consistent.

Link: http://lkml.kernel.org/r/20171004171541.1495-2-aarcange@redhat.comSigned-off-by: NAndrea Arcangeli <aarcange@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Silences the checker:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf.h' differs from latest version at 'include/uapi/linux/bpf.h'

The 90caccdd ("bpf: fix bpf_tail_call() x64 JIT") cset only updated
a comment in uapi/bpf.h.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-rwx2cqbf0x1lwa1krsr6e6hd@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Currently, perf record is broken on arm/arm64 systems when the PMU is
specified explicitly as part of the event, e.g.

$ ./perf record -e armv8_cortex_a53/cpu_cycles/u true

In such cases, perf record fails to open events unless
perf_event_paranoid is set to -1, even if the PMU in question supports
mode exclusion. Further, even when perf_event_paranoid is toggled, no
samples are recorded.

This is an unintended side effect of commit:

  e3ba76de ("perf tools: Force uncore events to system wide monitoring)

... which assumes that if a PMU has an associated cpu_map, it is an
uncore PMU, and forces events for such PMUs to be system-wide.

This is not true for arm/arm64 systems, which can have heterogeneous
CPUs. To account for this, multiple CPU PMUs are exposed, each with a
"cpus" field under sysfs, which the perf tool parses into a cpu_map. ARM
PMUs do not have a "cpumask" file, and only have a "cpus" file. For the
gory details as to why, see commit:

 7e3fcffe ("perf pmu: Support alternative sysfs cpumask")

Given all of this, we can instead identify uncore PMUs by explicitly
checking for a "cpumask" file, and restore arm/arm64 PMU support back to
a working state. This patch does so, adding a new perf_pmu::is_uncore
field, and splitting the existing cpumask parsing so that it can be
reused.
Signed-off-by: NMark Rutland <mark.rutland@arm.com>
Tested-by Will Deacon <will.deacon@arm.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: 4.12+ <stable@vger.kernel.org>
Fixes: e3ba76de ("perf tools: Force uncore events to system wide monitoring)
Link: http://lkml.kernel.org/r/1507315102-5942-1-git-send-email-mark.rutland@arm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Prior to commit 55b9b508 ("perf script: Support -F brstack,dso and
brstacksym,dso"), we were printing a space before the brstack data. It
seems that this space was important.  Without it, parsing is difficult.

Very sorry for the mistake.

Notice here how the "ip" and "brstack" run together:

$ perf script -F ip,brstack | head -n 1
          22e18c40x22e19e2/0x22e190b/P/-/-/0 0x22e19a1/0x22e19d0/P/-/-/0 0x22e195d/0x22e1990/P/-/-/0 0x22e18e9/0x22e1943/P/-/-/0 0x22e1a69/0x22e18c0/P/-/-/0 0x22e19f7/0x22e1a20/P/-/-/0 0x22e1910/0x22e19ee/P/-/-/0 0x22e19e2/0x22e190b/P/-/-/0 0x22e19a1/0x22e19d0/P/-/-/0 0x22e195d/0x22e1990/P/-/-/0 0x22e18e9/0x22e1943/P/-/-/0 0x22e1a69/0x22e18c0/P/-/-/0 0x22e19f7/0x22e1a20/P/-/-/0 0x22e1910/0x22e19ee/P/-/-/0 0x22e19e2/0x22e190b/P/-/-/0 0x22e19a1/0x22e19d0/P/-/-/0

After this diff, sanity is restored:

$ perf script -F ip,brstack | head -n 1
          22e18c4 0x22e19e2/0x22e190b/P/-/-/0  0x22e19a1/0x22e19d0/P/-/-/0  0x22e195d/0x22e1990/P/-/-/0  0x22e18e9/0x22e1943/P/-/-/0  0x22e1a69/0x22e18c0/P/-/-/0  0x22e19f7/0x22e1a20/P/-/-/0  0x22e1910/0x22e19ee/P/-/-/0  0x22e19e2/0x22e190b/P/-/-/0  0x22e19a1/0x22e19d0/P/-/-/0  0x22e195d/0x22e1990/P/-/-/0  0x22e18e9/0x22e1943/P/-/-/0  0x22e1a69/0x22e18c0/P/-/-/0  0x22e19f7/0x22e1a20/P/-/-/0  0x22e1910/0x22e19ee/P/-/-/0  0x22e19e2/0x22e190b/P/-/-/0  0x22e19a1/0x22e19d0/P/-/-/0
Signed-off-by: NMark Santaniello <marksan@fb.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: 4.13+ <stable@vger.kernel.org>
Fixes: 55b9b508 ("perf script: Support -F brstack,dso and brstacksym,dso")
Link: http://lkml.kernel.org/r/20171006080722.3442046-1-marksan@fb.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

The > should be >= so that we don't write one element beyond the end of
the array.

Fixes: 16e78122 ("selftests/net: Add a test to validate behavior of rx timestamps")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix fix regression in silencing output from RUN_TESTS introduced by
commit <8230b905> selftests: mqueue: Use full path to run tests
from Makefile
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

sysret_ss_attrs fails to compile leading x86 test run to fail on systems
configured to build using PIE by default. Add -no-pie fix it.

Relocation might still fail if relocated above 4G. For now this change
fixes the build and runs x86 tests.

tools/testing/selftests/x86$ make
gcc -m64 -o .../tools/testing/selftests/x86/single_step_syscall_64 -O2
-g -std=gnu99 -pthread -Wall  single_step_syscall.c -lrt -ldl
gcc -m64 -o .../tools/testing/selftests/x86/sysret_ss_attrs_64 -O2 -g
-std=gnu99 -pthread -Wall  sysret_ss_attrs.c thunks.S -lrt -ldl
/usr/bin/ld: /tmp/ccS6pvIh.o: relocation R_X86_64_32S against `.text'
can not be used when making a shared object; recompile with -fPIC
/usr/bin/ld: final link failed: Nonrepresentable section on output
collect2: error: ld returned 1 exit status
Makefile:49: recipe for target
'.../tools/testing/selftests/x86/sysret_ss_attrs_64' failed
make: *** [.../tools/testing/selftests/x86/sysret_ss_attrs_64] Error 1
Suggested-by: NAndy Lutomirski <luto@kernel.org>
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

Two functions from different binaries can have same start address. Thus,
comparing only start address in match_chain() leads to inconsistent
callchains. Fix this by adding a check for dsos as well.

Ex, https://www.spinics.net/lists/linux-perf-users/msg04067.htmlReported-by: NAlexander Pozdneev <pozdneyev@gmail.com>
Signed-off-by: NRavi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Yao Jin <yao.jin@linux.intel.com>
Cc: zhangmengting@huawei.com
Link: http://lkml.kernel.org/r/20171005091234.5874-1-ravi.bangoria@linux.vnet.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

On s390x perf test 1 failed. It turned out that commit cf6383f7
("perf report: Fix kernel symbol adjustment for s390x") was incorrect.

The previous implementation in dso__load_sym() is also suitable for
s390x.

Therefore this patch undoes commit cf6383f7Signed-off-by: NThomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Fixes: cf6383f7 ("perf report: Fix kernel symbol adjustment for s390x")
LPU-Reference: 20170915071404.58398-2-tmricht@linux.vnet.ibm.com
Link: http://lkml.kernel.org/n/tip-v101o8k25vuja2ogosgf15yy@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

On s390x perf test 1 failed. It turned out that commit 4a084ecf
("perf report: Fix module symbol adjustment for s390x") was incorrect.
The previous implementation in dso__load_sym() is also suitable for
s390x.

Therefore this patch undoes commit 4a084ecf.
Signed-off-by: NThomas-Mich Richter <tmricht@linux.vnet.ibm.com>
Cc: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Cc: Zvonko Kosic <zvonko.kosic@de.ibm.com>
Fixes: 4a084ecf ("perf report: Fix module symbol adjustment for s390x")
LPU-Reference: 20170915071404.58398-1-tmricht@linux.vnet.ibm.com
Link: http://lkml.kernel.org/n/tip-5ani7ly57zji7s0hmzkx416l@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Arnd Bergmann reported a bunch of warnings like:

  crypto/jitterentropy.o: warning: objtool: jent_fold_time()+0x3b: call without frame pointer save/setup
  crypto/jitterentropy.o: warning: objtool: jent_stuck()+0x1d: call without frame pointer save/setup
  crypto/jitterentropy.o: warning: objtool: jent_unbiased_bit()+0x15: call without frame pointer save/setup
  crypto/jitterentropy.o: warning: objtool: jent_read_entropy()+0x32: call without frame pointer save/setup
  crypto/jitterentropy.o: warning: objtool: jent_entropy_collector_free()+0x19: call without frame pointer save/setup

and

  arch/x86/events/core.o: warning: objtool: collect_events uses BP as a scratch register
  arch/x86/events/core.o: warning: objtool: events_ht_sysfs_show()+0x22: call without frame pointer save/setup

With certain rare configurations, GCC sometimes sets up the frame
pointer with:

  lea    (%rsp),%rbp

instead of:

  mov    %rsp,%rbp

The instructions are equivalent, so treat the former like the latter.
Reported-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/a468af8b28a69b83fffc6d7668be9b6fcc873699.1506526584.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

When timer_create() fails on a bootime or realtime clock, setup_timer()
returns 0 as if timer has been set. Callers wait forever for the timer
to expire.

This hang is seen on a system that doesn't have support for:

CLOCK_REALTIME_ALARM   ABSTIME missing CAP_WAKE_ALARM? : [UNSUPPORTED]

Test hangs waiting for a timer that hasn't been set to expire. Fix
setup_timer() to return 1, add handling in callers to detect the
unsupported case and return 0 without waiting to not fail the test.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

do_timer_oneshot() uses select() as a timer with FD_SETSIZE and readfs
is cleared with FD_ZERO without FD_SET.

When stdout and stderr are redirected, the test hangs in select forever.
Fix the problem calling select() with readfds empty and nfds zero. This
is sufficient for using select() for timer.

With this fix "./set-timer-lat > /dev/null 2>&1" no longer hangs.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>
Acked-by: NGreg Hackmann <ghackmann@google.com>
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

to fix the following issue:
------------------
TAP version 13
selftests: run_tests.sh
========================================
selftests: Warning: file run_tests.sh is not executable, correct this.
not ok 1..1 selftests: run_tests.sh [FAIL]
------------------
Signed-off-by: NLi Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

The 2.26 release of glibc changed how siginfo_t is defined, and the earlier
work-around to using the kernel definition are no longer needed. The old
way needs to stay around for a while, though.
Reported-by: NSeth Forshee <seth.forshee@canonical.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: linux-kselftest@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: NKees Cook <keescook@chromium.org>
Tested-by: NSeth Forshee <seth.forshee@canonical.com>
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

Fix for loops in targets to run silently to avoid cluttering the test
results.

Suppresses the following from targets:

for DIR in functional; do               \
        BUILD_TARGET=./tools/testing/selftests/futex/$DIR; \
        mkdir $BUILD_TARGET  -p;        \
        make OUTPUT=$BUILD_TARGET -C $DIR all;\
done

./tools/testing/selftests/futex/run.sh
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>
Reviewed-by: NDarren Hart (VMware) <dvhart@infradead.org>
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

Fix for loops in targets to run silently to avoid cluttering the test
results.

Suppresses the following from targets: e.g run from breakpoints

for TARGET in breakpoints; do		\
	BUILD_TARGET=$BUILD/$TARGET;	\
	mkdir $BUILD_TARGET  -p;	\
	make OUTPUT=$BUILD_TARGET -C $TARGET;\
done;
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

Use full path including $(OUTPUT) to run tests from Makefile for
normal case when objects reside in the source tree as well as when
objects are relocated with make O=dir. In both cases $(OUTPUT) will
be set correctly by lib.mk.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

For make O=dir run_tests to work, test scripts from sub-directories
need to be copied over to the object directory. Running tests from the
object directory is necessary to avoid making the source tree dirty.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>
Reviewed-by: NDarren Hart (VMware) <dvhart@infradead.org>
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

The build of kernel v4.14-rc1 for i686 fails on RHEL 6 with the error
in tools/perf:

  util/syscalltbl.c:157: error: expected ';', ',' or ')' before '__maybe_unused'
  mv: cannot stat `util/.syscalltbl.o.tmp': No such file or directory

Fix it by placing/moving:

  #include <linux/compiler.h>

  outside of #ifdef HAVE_SYSCALL_TABLE block.
Signed-off-by: NAkemi Yagi <toracat@elrepo.org>
Cc: Alan Bartlett <ajb@elrepo.org>
Link: http://lkml.kernel.org/r/oq41r8$1v9$1@blaine.gmane.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

With --call-graph option, perf report can display call chains using
type, min percent threshold, optional print limit and order. And the
default call-graph parameter is 'graph,0.5,caller,function,percent'.

Before this patch, 'perf report --call-graph' shows incorrect debug
messages as below:

  # perf report --call-graph
  Invalid callchain mode: 0.5
  Invalid callchain order: 0.5
  Invalid callchain sort key: 0.5
  Invalid callchain config key: 0.5
  Invalid callchain mode: caller
  Invalid callchain mode: function
  Invalid callchain order: function
  Invalid callchain mode: percent
  Invalid callchain order: percent
  Invalid callchain sort key: percent

That is because in function __parse_callchain_report_opt(),each field of
the call-graph parameter is passed to parse_callchain_{mode,order,
sort_key,value} in turn until it meets the matching value.

For example, the order field "caller" is passed to
parse_callchain_mode() firstly and obviously it doesn't match any mode
field. Therefore parse_callchain_mode() will shows the debug message
"Invalid callchain mode: caller", which could confuse users.

The patch fixes this issue by moving the warning out of the function
parse_callchain_{mode,order,sort_key,value}.
Signed-off-by: NMengting Zhang <zhangmengting@huawei.com>
Acked-by: NJiri Olsa <jolsa@kernel.org>
Tested-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Li Bin <huawei.libin@huawei.com>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/1506154694-39691-1-git-send-email-zhangmengting@huawei.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Yet another fix for probing the max attr.precise_ip setting: it is not
enough settting attr.exclude_kernel for !root users, as they _can_
profile the kernel if the kernel.perf_event_paranoid sysctl is set to
-1, so check that as well.

Testing it:

As non root:

  $ sysctl kernel.perf_event_paranoid
  kernel.perf_event_paranoid = 2
  $ perf record sleep 1
  $ perf evlist -v
  cycles:uppp: ..., exclude_kernel: 1, ... precise_ip: 3, ...

Now as non-root, but with kernel.perf_event_paranoid set set to the
most permissive value, -1:

  $ sysctl kernel.perf_event_paranoid
  kernel.perf_event_paranoid = -1
  $ perf record sleep 1
  $ perf evlist -v
  cycles:ppp: ..., exclude_kernel: 0, ... precise_ip: 3, ...
  $

I.e. non-root, default kernel.perf_event_paranoid: :uppp modifier = not allowed to sample the kernel,
     non-root, most permissible kernel.perf_event_paranoid: :ppp = allowed to sample the kernel.

In both cases, use the highest available precision: attr.precise_ip = 3.
Reported-and-Tested-by: NIngo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: d37a3697 ("perf evsel: Fix attr.exclude_kernel setting for default cycles:p")
Link: http://lkml.kernel.org/n/tip-nj2qkf75xsd6pw6hhjzfqqdx@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Time for a sync with ABI/uapi headers with the upcoming v4.14 kernel.

None of the ABI changes require any source code level changes to our
existing in-kernel tooling code:

  - tools/arch/s390/include/uapi/asm/kvm.h:

      New KVM_S390_VM_TOD_EXT ABI, not used by in-kernel tooling.

  - tools/arch/x86/include/asm/cpufeatures.h:
    tools/arch/x86/include/asm/disabled-features.h:

      New PCID, SME and VGIF x86 CPU feature bits defined.

  - tools/include/asm-generic/hugetlb_encode.h:
    tools/include/uapi/asm-generic/mman-common.h:
    tools/include/uapi/linux/mman.h:

      Two new madvise() flags, plus a hugetlb system call mmap flags
      restructuring/extension changes.

  - tools/include/uapi/drm/drm.h:
    tools/include/uapi/drm/i915_drm.h:

      New drm_syncobj_create flags definitions, new drm_syncobj_wait
      and drm_syncobj_array ABIs. DRM_I915_PERF_* calls and a new
      I915_PARAM_HAS_EXEC_FENCE_ARRAY ABI for the Intel driver.

  - tools/include/uapi/linux/bpf.h:

      New bpf_sock fields (::mark and ::priority), new XDP_REDIRECT
      action, new kvm_ppc_smmu_info fields (::data_keys, instr_keys)
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yao Jin <yao.jin@linux.intel.com>
Link: http://lkml.kernel.org/r/20170913073823.lxmi4c7ejqlfabjx@gmail.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

Now that I'm switching the container builds from using a local volume
pointing to the kernel repository with the perf sources, instead getting
a detached tarball to be able to use a container cluster, some places
broke because I forgot to put some of the required files in
tools/perf/MANIFEST, namely some bitsperlong.h files.

So, to fix it do the same as for tools/build/ and pack the whole
tools/arch/ directory.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-wmenpjfjsobwdnfde30qqncj@git.kernel.orgSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>

For inline asm statements which have a CALL instruction, we list the
stack pointer as a constraint to convince GCC to ensure the frame
pointer is set up first:

  static inline void foo()
  {
	register void *__sp asm(_ASM_SP);
	asm("call bar" : "+r" (__sp))
  }

Unfortunately, that pattern causes Clang to corrupt the stack pointer.

The fix is easy: convert the stack pointer register variable to a global
variable.

It should be noted that the end result is different based on the GCC
version.  With GCC 6.4, this patch has exactly the same result as
before:

	defconfig	defconfig-nofp	distro		distro-nofp
 before	9820389		9491555		8816046		8516940
 after	9820389		9491555		8816046		8516940

With GCC 7.2, however, GCC's behavior has changed.  It now changes its
behavior based on the conversion of the register variable to a global.
That somehow convinces it to *always* set up the frame pointer before
inserting *any* inline asm.  (Therefore, listing the variable as an
output constraint is a no-op and is no longer necessary.)  It's a bit
overkill, but the performance impact should be negligible.  And in fact,
there's a nice improvement with frame pointers disabled:

	defconfig	defconfig-nofp	distro		distro-nofp
 before	9796316		9468236		9076191		8790305
 after	9796957		9464267		9076381		8785949

So in summary, while listing the stack pointer as an output constraint
is no longer necessary for newer versions of GCC, it's still needed for
older versions.
Suggested-by: NAndrey Ryabinin <aryabinin@virtuozzo.com>
Reported-by: NMatthias Kaehlcke <mka@chromium.org>
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/3db862e970c432ae823cf515c52b54fec8270e0e.1505942196.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

The kbuild bot reported the following warning with GCC 4.4 and a
randconfig:

  net/socket.o: warning: objtool: compat_sock_ioctl()+0x1083: stack state mismatch: cfa1=7+160 cfa2=-1+0

This is caused by another GCC non-optimization, where it backs up and
restores the stack pointer for no apparent reason:

    2f91:       48 89 e0                mov    %rsp,%rax
    2f94:       4c 89 e7                mov    %r12,%rdi
    2f97:       4c 89 f6                mov    %r14,%rsi
    2f9a:       ba 20 00 00 00          mov    $0x20,%edx
    2f9f:       48 89 c4                mov    %rax,%rsp

This issue would have been happily ignored before the following commit:

  dd88a0a0 ("objtool: Handle GCC stack pointer adjustment bug")

But now that objtool is paying attention to such stack pointer writes
to/from a register, it needs to understand them properly.  In this case
that means recognizing that the "mov %rsp, %rax" instruction is
potentially a backup of the stack pointer.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NJosh Poimboeuf <jpoimboe@redhat.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthias Kaehlcke <mka@chromium.org>
Cc: Miguel Bernal Marin <miguel.bernal.marin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: dd88a0a0 ("objtool: Handle GCC stack pointer adjustment bug")
Link: http://lkml.kernel.org/r/8c7aa8e9a36fbbb6655d9d8e7cea58958c912da8.1505942196.git.jpoimboe@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

For make O=dir run_tests to work, test scripts, test files, and other
dependencies need to be copied over to the object directory. Running
tests from the object directory is necessary to avoid making the source
tree dirty.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

sync test fails to build when object directory is specified to relocate
object files. Fix it to specify the correct path. Fix clean target to
remove objects. Also include simplified logic to use TEST_CUSTOM_PROGS
in build and clean targets instead of hard-coding the test name each
time.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

lib.mk var TEST_CUSTOM_PROGS is for tests that need custom build
rules. TEST_PROGS is used for test shell scripts. Fix it to use
TEST_CUSTOM_PROGS. lib.mk will run and install them.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

Some tests such as sync can't use generic build rules in lib.mk and require
custom rules. Currently there is no provision to allow custom builds and
test such as sync use TEST_PROGS which is reserved for test shell scripts.
Add TEST_CUSTOM_PROGS variable to lib.mk to run and install custom tests
built by individual test make files.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

TEST_PROGS should be used for test scripts that don't ned to be built.
Use TEST_GEN_PROGS instead which is intended for test executables.

Remove clean target and let the common clean take care of cleaning.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

Fix test executable status check to use full path for make O=dir case,m
when tests are relocated to user specified object directory. Without the
full path, this check fails to find the file and fails the test.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

kselftest target fails when object directory is specified to relocate
objects. Inherited "LDFLAGS = -m" fails the test builds. Clear it.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>

kselftest and kselftest-clean targets fail when object directory is
specified to relocate objects. Main Makefile make O= path clears the
built-in defines LINK.c, COMPILE.S, LINK.S, and RM that are used in
lib.mk to build and clean targets. Define them.
Signed-off-by: NShuah Khan <shuahkh@osg.samsung.com>