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Linux kernel
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Pull perf tooling fixes from Arnaldo Carvalho de Melo:
- Avoid write of uninitialized memory when generating PERF_RECORD_MMAP*
records.
- Fix 'perf top' BPF support related crash with perf_event_paranoid=3 +
kptr_restrict.
- Validate raw event with sysfs exported format bits.
- Fix waipid on SIGCHLD delivery bugs in 'perf daemon'.
- Change to use bash for daemon test on Debian, where the default is
dash and thus fails for use of bashisms in this test.
- Fix memory leak in vDSO found using ASAN.
- Remove now useless (due to the fact that BPF now supports static
vars) failing sub test "BPF relocation checker".
- Fix auxtrace queue conflict.
- Sync linux/kvm.h with the kernel sources.
* tag 'perf-tools-fixes-for-v5.12-2020-03-28' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf test: Change to use bash for daemon test
perf record: Fix memory leak in vDSO found using ASAN
perf test: Remove now useless failing sub test "BPF relocation checker"
perf daemon: Return from kill functions
perf daemon: Force waipid for all session on SIGCHLD delivery
perf top: Fix BPF support related crash with perf_event_paranoid=3 + kptr_restrict
perf pmu: Validate raw event with sysfs exported format bits
perf synthetic events: Avoid write of uninitialized memory when generating PERF_RECORD_MMAP* records
tools headers UAPI: Sync linux/kvm.h with the kernel sources
perf synthetic-events: Fix uninitialized 'kernel_thread' variable
perf auxtrace: Fix auxtrace queue conflict
Pull auxdisplay fix from Miguel Ojeda:
"Remove in_interrupt() usage (Sebastian Andrzej Siewior)"
* tag 'auxdisplay-for-linus-v5.12-rc6' of git://github.com/ojeda/linux:
auxdisplay: Remove in_interrupt() usage.
When executing the daemon test on Arm64 and x86 with Debian (Buster)
distro, both skip the test case with the log:
# ./perf test -v 76
76: daemon operations :
--- start ---
test child forked, pid 11687
test daemon list
trap: SIGINT: bad trap
./tests/shell/daemon.sh: 173: local: cpu-clock: bad variable name
test child finished with -2
---- end ----
daemon operations: Skip
So the error happens for the variable expansion when use local variable
in the shell script. Since Debian Buster uses dash but not bash as
non-interactive shell, when execute the daemon testing, it hits a known
issue for dash which was reported [1].
To resolve this issue, one option is to add double quotes for all local
variables assignment, so need to change the code from:
local line=`perf daemon --config ${config} -x: | head -2 | tail -1`
... to:
local line="`perf daemon --config ${config} -x: | head -2 | tail -1`"
But the testing script has bunch of local variables, this leads to big
changes for whole script.
On the other hand, the testing script asks to use the "local" feature
which is bash-specific, so this patch explicitly uses "#!/bin/bash" to
ensure running the script with bash.
After:
# ./perf test -v 76
76: daemon operations :
--- start ---
test child forked, pid 11329
test daemon list
test daemon reconfig
test daemon stop
test daemon signal
signal 12 sent to session 'test [11596]'
signal 12 sent to session 'test [11596]'
test daemon ping
test daemon lock
test child finished with 0
---- end ----
daemon operations: Ok
[1] https://bugs.launchpad.net/ubuntu/+source/dash/+bug/139097
Fixes: 2291bb915b55 ("perf tests: Add daemon 'list' command test")
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210320104554.529213-1-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull x86 fixes from Ingo Molnar:
"Two fixes:
- Fix build failure on Ubuntu with new GCC packages that turn
on -fcf-protection
- Fix SME memory encryption PTE encoding bug - AFAICT the code
worked on 4K page sizes (level 1) but had the wrong shift at
higher page level orders (level 2 and higher)"
* tag 'x86-urgent-2021-03-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/build: Turn off -fcf-protection for realmode targets
x86/mem_encrypt: Correct physical address calculation in __set_clr_pte_enc()
charlcd_write() is invoked as a VFS->write() callback and as such it is
always invoked from preemptible context and may sleep.
charlcd_puts() is invoked from register/unregister callback which is
preemptible. The reboot notifier callback is also invoked from
preemptible context.
Therefore there is no need to use in_interrupt() to figure out if it
is safe to sleep because it always is. in_interrupt() and related
context checks are being removed from non-core code.
Using schedule() to schedule (and be friendly to others) is
discouraged and cond_resched() should be used instead.
Remove in_interrupt() and use cond_resched() to schedule every 32
iterations if needed.
Link: https://lkml.kernel.org/r/20200914204209.256266093@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
[mo: fixed a couple typos in comment and commit message]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
I got several memory leak reports from Asan with a simple command. It
was because VDSO is not released due to the refcount. Like in
__dsos_addnew_id(), it should put the refcount after adding to the list.
$ perf record true
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.030 MB perf.data (10 samples) ]
=================================================================
==692599==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 439 byte(s) in 1 object(s) allocated from:
#0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
#1 0x559bce4aa8ee in dso__new_id util/dso.c:1256
#2 0x559bce59245a in __machine__addnew_vdso util/vdso.c:132
#3 0x559bce59245a in machine__findnew_vdso util/vdso.c:347
#4 0x559bce50826c in map__new util/map.c:175
#5 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787
#6 0x559bce512f6b in machines__deliver_event util/session.c:1481
#7 0x559bce515107 in perf_session__deliver_event util/session.c:1551
#8 0x559bce51d4d2 in do_flush util/ordered-events.c:244
#9 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323
#10 0x559bce519bea in __perf_session__process_events util/session.c:2268
#11 0x559bce519bea in perf_session__process_events util/session.c:2297
#12 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017
#13 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234
#14 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026
#15 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858
#16 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
#17 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
#18 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
#19 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539
#20 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308
Indirect leak of 32 byte(s) in 1 object(s) allocated from:
#0 0x7fea52341037 in __interceptor_calloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:154
#1 0x559bce520907 in nsinfo__copy util/namespaces.c:169
#2 0x559bce50821b in map__new util/map.c:168
#3 0x559bce503c92 in machine__process_mmap2_event util/machine.c:1787
#4 0x559bce512f6b in machines__deliver_event util/session.c:1481
#5 0x559bce515107 in perf_session__deliver_event util/session.c:1551
#6 0x559bce51d4d2 in do_flush util/ordered-events.c:244
#7 0x559bce51d4d2 in __ordered_events__flush util/ordered-events.c:323
#8 0x559bce519bea in __perf_session__process_events util/session.c:2268
#9 0x559bce519bea in perf_session__process_events util/session.c:2297
#10 0x559bce2e7a52 in process_buildids /home/namhyung/project/linux/tools/perf/builtin-record.c:1017
#11 0x559bce2e7a52 in record__finish_output /home/namhyung/project/linux/tools/perf/builtin-record.c:1234
#12 0x559bce2ed4f6 in __cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2026
#13 0x559bce2ed4f6 in cmd_record /home/namhyung/project/linux/tools/perf/builtin-record.c:2858
#14 0x559bce422db4 in run_builtin /home/namhyung/project/linux/tools/perf/perf.c:313
#15 0x559bce2acac8 in handle_internal_command /home/namhyung/project/linux/tools/perf/perf.c:365
#16 0x559bce2acac8 in run_argv /home/namhyung/project/linux/tools/perf/perf.c:409
#17 0x559bce2acac8 in main /home/namhyung/project/linux/tools/perf/perf.c:539
#18 0x7fea51e76d09 in __libc_start_main ../csu/libc-start.c:308
SUMMARY: AddressSanitizer: 471 byte(s) leaked in 2 allocation(s).
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210315045641.700430-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull locking fix from Ingo Molnar:
"Fix the non-debug mutex_lock_io_nested() method to map to
mutex_lock_io() instead of mutex_lock().
Right now nothing uses this API explicitly, but this is an
accident waiting to happen"
* tag 'locking-urgent-2021-03-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/mutex: Fix non debug version of mutex_lock_io_nested()
The new Ubuntu GCC packages turn on -fcf-protection globally,
which causes a build failure in the x86 realmode code:
cc1: error: ‘-fcf-protection’ is not compatible with this target
Turn it off explicitly on compilers that understand this option.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210323124846.1584944-1-arnd@kernel.org
For some time now the 'perf test 42: BPF filter' returns an error on bpf
relocation subtest, at least on x86 and s390. This is caused by
d859900c4c56dc4f ("bpf, libbpf: support global data/bss/rodata sections")
which introduces support for global variables in eBPF programs.
Perf test 42.4 checks that the eBPF relocation fails when the eBPF program
contains a global variable. It returns OK when the eBPF program
could not be loaded and FAILED otherwise.
With above commit the test logic for the eBPF relocation is obsolete.
The loading of the eBPF now succeeds and the test always shows FAILED.
This patch removes the sub test completely.
Also a lot of eBPF program testing is done in the eBPF test suite,
it also contains tests for global variables.
Output before:
42: BPF filter :
42.1: Basic BPF filtering : Ok
42.2: BPF pinning : Ok
42.3: BPF prologue generation : Ok
42.4: BPF relocation checker : Failed
#
Output after:
# ./perf test -F 42
42: BPF filter :
42.1: Basic BPF filtering : Ok
42.2: BPF pinning : Ok
42.3: BPF prologue generation : Ok
#
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Suggested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20210324083734.1953123-1-tmricht@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull cifs fixes from Steve French:
"Five cifs/smb3 fixes, two for stable.
Includes an important fix for encryption and an ACL fix, as well as a
fix for possible reflink data corruption"
* tag '5.12-rc4-smb3' of git://git.samba.org/sfrench/cifs-2.6:
smb3: fix cached file size problems in duplicate extents (reflink)
cifs: Silently ignore unknown oplock break handle
cifs: revalidate mapping when we open files for SMB1 POSIX
cifs: Fix chmod with modefromsid when an older ACE already exists.
cifs: Adjust key sizes and key generation routines for AES256 encryption
If CONFIG_DEBUG_LOCK_ALLOC=n then mutex_lock_io_nested() maps to
mutex_lock() which is clearly wrong because mutex_lock() lacks the
io_schedule_prepare()/finish() invocations.
Map it to mutex_lock_io().
Fixes: f21860bac05b ("locking/mutex, sched/wait: Fix the mutex_lock_io_nested() define")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/878s6fshii.fsf@nanos.tec.linutronix.de
The pfn variable contains the page frame number as returned by the
pXX_pfn() functions, shifted to the right by PAGE_SHIFT to remove the
page bits. After page protection computations are done to it, it gets
shifted back to the physical address using page_level_shift().
That is wrong, of course, because that function determines the shift
length based on the level of the page in the page table but in all the
cases, it was shifted by PAGE_SHIFT before.
Therefore, shift it back using PAGE_SHIFT to get the correct physical
address.
[ bp: Rewrite commit message. ]
Fixes: dfaaec9033b8 ("x86: Add support for changing memory encryption attribute in early boot")
Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/81abbae1657053eccc535c16151f63cd049dcb97.1616098294.git.isaku.yamahata@intel.com
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