Patch set [1] introduced BTF_KIND_TAG to allow tagging
declarations for struct/union, struct/union field, var, func
and func arguments and these tags will be encoded into
dwarf. They are also encoded to btf by llvm for the bpf target.
After BTF_KIND_TAG is introduced, we intended to use it
for kernel __user attributes. But kernel __user is actually
a type attribute. Upstream and internal discussion showed
it is not a good idea to mix declaration attribute and
type attribute. So we proposed to introduce btf_type_tag
as a type attribute and existing btf_tag renamed to
btf_decl_tag ([2]).
This patch renamed BTF_KIND_TAG to BTF_KIND_DECL_TAG and some
other declarations with *_tag to *_decl_tag to make it clear
the tag is for declaration. In the future, BTF_KIND_TYPE_TAG
might be introduced per [3].
[1] https://lore.kernel.org/bpf/20210914223004.244411-1-yhs@fb.com/
[2] https://reviews.llvm.org/D111588
[3] https://reviews.llvm.org/D111199
Fixes: b5ea834dde ("bpf: Support for new btf kind BTF_KIND_TAG")
Fixes: 5b84bd1036 ("libbpf: Add support for BTF_KIND_TAG")
Fixes: 5c07f2fec0 ("bpftool: Add support for BTF_KIND_TAG")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211012164838.3345699-1-yhs@fb.com
Use get_unaligned() instead of memcpy() to access potentially unaligned
memory, which, when accessed through a pointer, leads to undefined
behavior. get_unaligned() describes much better what is happening there
anyway even if memcpy() does the job.
In addition, since perf tool builds with -Werror, it would fire with:
util/intel-pt-decoder/../../../arch/x86/lib/insn.c: In function '__insn_get_emulate_prefix':
tools/include/../include/asm-generic/unaligned.h:10:15: error: packed attribute is unnecessary [-Werror=packed]
10 | const struct { type x; } __packed *__pptr = (typeof(__pptr))(ptr); \
because -Werror=packed would complain if the packed attribute would have
no effect on the layout of the structure.
In this case, that is intentional so disable the warning only for that
compilation unit.
That part is Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
No functional changes.
Fixes: 5ba1071f75 ("x86/insn, tools/x86: Fix undefined behavior due to potential unaligned accesses")
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lkml.kernel.org/r/YVSsIkj9Z29TyUjE@zn.tnic
Picking the changes from:
09d2317440 ("ALSA: rawmidi: introduce SNDRV_RAWMIDI_IOCTL_USER_PVERSION")
Which entails no changes in the tooling side as it doesn't introduce new
SNDRV_PCM_IOCTL_ ioctls.
To silence this perf tools build warning:
Warning: Kernel ABI header at 'tools/include/uapi/sound/asound.h' differs from latest version at 'include/uapi/sound/asound.h'
diff -u tools/include/uapi/sound/asound.h include/uapi/sound/asound.h
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2021-09-17
We've added 63 non-merge commits during the last 12 day(s) which contain
a total of 65 files changed, 2653 insertions(+), 751 deletions(-).
The main changes are:
1) Streamline internal BPF program sections handling and
bpf_program__set_attach_target() in libbpf, from Andrii.
2) Add support for new btf kind BTF_KIND_TAG, from Yonghong.
3) Introduce bpf_get_branch_snapshot() to capture LBR, from Song.
4) IMUL optimization for x86-64 JIT, from Jie.
5) xsk selftest improvements, from Magnus.
6) Introduce legacy kprobe events support in libbpf, from Rafael.
7) Access hw timestamp through BPF's __sk_buff, from Vadim.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (63 commits)
selftests/bpf: Fix a few compiler warnings
libbpf: Constify all high-level program attach APIs
libbpf: Schedule open_opts.attach_prog_fd deprecation since v0.7
selftests/bpf: Switch fexit_bpf2bpf selftest to set_attach_target() API
libbpf: Allow skipping attach_func_name in bpf_program__set_attach_target()
libbpf: Deprecated bpf_object_open_opts.relaxed_core_relocs
selftests/bpf: Stop using relaxed_core_relocs which has no effect
libbpf: Use pre-setup sec_def in libbpf_find_attach_btf_id()
bpf: Update bpf_get_smp_processor_id() documentation
libbpf: Add sphinx code documentation comments
selftests/bpf: Skip btf_tag test if btf_tag attribute not supported
docs/bpf: Add documentation for BTF_KIND_TAG
selftests/bpf: Add a test with a bpf program with btf_tag attributes
selftests/bpf: Test BTF_KIND_TAG for deduplication
selftests/bpf: Add BTF_KIND_TAG unit tests
selftests/bpf: Change NAME_NTH/IS_NAME_NTH for BTF_KIND_TAG format
selftests/bpf: Test libbpf API function btf__add_tag()
bpftool: Add support for BTF_KIND_TAG
libbpf: Add support for BTF_KIND_TAG
libbpf: Rename btf_{hash,equal}_int to btf_{hash,equal}_int_tag
...
====================
Link: https://lore.kernel.org/r/20210917173738.3397064-1-ast@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
LLVM14 added support for a new C attribute ([1])
__attribute__((btf_tag("arbitrary_str")))
This attribute will be emitted to dwarf ([2]) and pahole
will convert it to BTF. Or for bpf target, this
attribute will be emitted to BTF directly ([3], [4]).
The attribute is intended to provide additional
information for
- struct/union type or struct/union member
- static/global variables
- static/global function or function parameter.
For linux kernel, the btf_tag can be applied
in various places to specify user pointer,
function pre- or post- condition, function
allow/deny in certain context, etc. Such information
will be encoded in vmlinux BTF and can be used
by verifier.
The btf_tag can also be applied to bpf programs
to help global verifiable functions, e.g.,
specifying preconditions, etc.
This patch added basic parsing and checking support
in kernel for new BTF_KIND_TAG kind.
[1] https://reviews.llvm.org/D106614
[2] https://reviews.llvm.org/D106621
[3] https://reviews.llvm.org/D106622
[4] https://reviews.llvm.org/D109560
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210914223015.245546-1-yhs@fb.com
When building objtool with HOSTCC=clang, there are several errors along
the lines of
orc_dump.c:201:28: error: unknown attribute 'error' ignored [-Werror,-Wunknown-attributes]
This occurs after commit 4e59869aa6 ("compiler-gcc.h: drop checks for
older GCC versions"), which removed the GCC_VERSION gating. The removed
version check just so happened to prevent __compiletime_error() from
being defined with clang because it pretends to be GCC 4.2.1 for
compatibility but the error attribute was not added to clang until
14.0.0.
Commit 815f0ddb34 ("include/linux/compiler*.h: make compiler-*.h
mutually exclusive") and commit a3f8a30f3f ("Compiler Attributes: use
feature checks instead of version checks") refactored the handling of
attributes in the main kernel to avoid situations like this but that
refactoring has never been done for the tools directory.
Refactoring is a rather large undertaking and this has never been an
issue before so instead, just guard the definition of
__compiletime_error() with __has_attribute() so that there are no more
errors.
Fixes: 4e59869aa6 ("compiler-gcc.h: drop checks for older GCC versions")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce bpf_get_branch_snapshot(), which allows tracing pogram to get
branch trace from hardware (e.g. Intel LBR). To use the feature, the
user need to create perf_event with proper branch_record filtering
on each cpu, and then calls bpf_get_branch_snapshot in the bpf function.
On Intel CPUs, VLBR event (raw event 0x1b00) can be use for this.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210910183352.3151445-3-songliubraving@fb.com
Merge patch series from Nick Desaulniers to update the minimum gcc
version to 5.1.
This is some of the left-overs from the merge window that I didn't want
to deal with yesterday, so it comes in after -rc1 but was sent before.
Gcc-4.9 support has been an annoyance for some time, and with -Werror I
had the choice of applying a fairly big patch from Kees Cook to remove a
fair number of initializer warnings (still leaving some), or this patch
series from Nick that just removes the source of the problem.
The initializer cleanups might still be worth it regardless, but
honestly, I preferred just tackling the problem with gcc-4.9 head-on.
We've been more aggressiuve about no longer having to care about
compilers that were released a long time ago, and I think it's been a
good thing.
I added a couple of patches on top to sort out a few left-overs now that
we no longer support gcc-4.x.
As noted by Arnd, as a result of this minimum compiler version upgrade
we can probably change our use of '--std=gnu89' to '--std=gnu11', and
finally start using local loop declarations etc. But this series does
_not_ yet do that.
Link: https://lore.kernel.org/all/20210909182525.372ee687@canb.auug.org.au/
Link: https://lore.kernel.org/lkml/CAK7LNASs6dvU6D3jL2GG3jW58fXfaj6VNOe55NJnTB8UPuk2pA@mail.gmail.com/
Link: https://github.com/ClangBuiltLinux/linux/issues/1438
* emailed patches from Nick Desaulniers <ndesaulniers@google.com>:
Drop some straggling mentions of gcc-4.9 as being stale
compiler_attributes.h: drop __has_attribute() support for gcc4
vmlinux.lds.h: remove old check for GCC 4.9
compiler-gcc.h: drop checks for older GCC versions
Makefile: drop GCC < 5 -fno-var-tracking-assignments workaround
arm64: remove GCC version check for ARCH_SUPPORTS_INT128
powerpc: remove GCC version check for UPD_CONSTR
riscv: remove Kconfig check for GCC version for ARCH_RV64I
Kconfig.debug: drop GCC 5+ version check for DWARF5
mm/ksm: remove old GCC 4.9+ check
compiler.h: drop fallback overflow checkers
Documentation: raise minimum supported version of GCC to 5.1
Picking the changes from:
17ce9c61c7 ("drm: document DRM_IOCTL_MODE_RMFB")
Doesn't result in any tooling changes:
$ tools/perf/trace/beauty/drm_ioctl.sh > before
$ cp include/uapi/drm/drm.h tools/include/uapi/drm/drm.h
$ tools/perf/trace/beauty/drm_ioctl.sh > after
$ diff -u before after
Silencing these perf build warnings:
Warning: Kernel ABI header at 'tools/include/uapi/drm/drm.h' differs from latest version at 'include/uapi/drm/drm.h'
diff -u tools/include/uapi/drm/drm.h include/uapi/drm/drm.h
Cc: Simon Ser <contact@emersion.fr>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick the changes in:
b65a948973 ("drm/i915/userptr: Probe existence of backing struct pages upon creation")
ee242ca704 ("drm/i915/guc: Implement GuC priority management")
81340cf3bd ("drm/i915/uapi: reject set_domain for discrete")
7961c5b60f ("drm/i915: Add TTM offset argument to mmap.")
aef7b67a79 ("drm/i915/uapi: convert drm_i915_gem_userptr to kernel doc")
e7737b67ab ("drm/i915/uapi: reject caching ioctls for discrete")
3aa8c57fe2 ("drm/i915/uapi: convert drm_i915_gem_set_domain to kernel doc")
289f5a7200 ("drm/i915/uapi: convert drm_i915_gem_caching to kernel doc")
4a766ae40e ("drm/i915: Drop the CONTEXT_CLONE API (v2)")
6ff6d61dd2 ("drm/i915: Drop I915_CONTEXT_PARAM_NO_ZEROMAP")
fe4751c3d5 ("drm/i915: Drop I915_CONTEXT_PARAM_RINGSIZE")
577729533c ("drm/i915: Document the Virtual Engine uAPI")
c649432e86 ("drm/i915: Fix busy ioctl commentary")
That doesn't result in any changes to tooling as no new ioctl were
added (at least not perceived by tools/perf/trace/beauty/drm_ioctl.sh).
Addressing this perf build warning:
Warning: Kernel ABI header at 'tools/include/uapi/drm/i915_drm.h' differs from latest version at 'include/uapi/drm/i915_drm.h'
diff -u tools/include/uapi/drm/i915_drm.h include/uapi/drm/i915_drm.h
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jason Ekstrand <jason@jlekstrand.net>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick the change in:
7957d93bf3 ("block: add ioctl to read the disk sequence number")
It adds a new ioctl, but we are still not using that to generate tables
for 'perf trace', so no changes in tooling.
This silences this perf build warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/fs.h' differs from latest version at 'include/uapi/linux/fs.h'
diff -u tools/include/uapi/linux/fs.h include/uapi/linux/fs.h
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matteo Croce <mcroce@microsoft.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick the changes in:
db243b7964 ("net/ipv4/ipv6: Replace one-element arraya with flexible-array members")
2d3e5caf96 ("net/ipv4: Replace one-element array with flexible-array member")
That don't result in any change in tooling, the structs changed remains
with the same layout.
This addresses this build warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/in.h' differs from latest version at 'include/uapi/linux/in.h'
diff -u tools/include/uapi/linux/in.h include/uapi/linux/in.h
Cc: David S. Miller <davem@davemloft.net>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
BPF programs may want to know hardware timestamps if NIC supports
such timestamping.
Expose this data as hwtstamp field of __sk_buff the same way as
gso_segs/gso_size. This field could be accessed from the same
programs as tstamp field, but it's read-only field. Explicit test
to deny access to padding data is added to bpf_skb_is_valid_access.
Also update BPF_PROG_TEST_RUN tests of the feature.
Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210909220409.8804-2-vfedorenko@novek.ru
To pick the changes from:
9ffb14ef61 ("move_mount: allow to add a mount into an existing group")
That ends up adding support for the new MOVE_MOUNT_SET_GROUP move_mount
flag.
$ tools/perf/trace/beauty/move_mount_flags.sh > before
$ cp include/uapi/linux/mount.h tools/include/uapi/linux/mount.h
$ tools/perf/trace/beauty/move_mount_flags.sh > after
$ diff -u before after
--- before 2021-09-10 12:28:43.865279808 -0300
+++ after 2021-09-10 12:28:50.183429184 -0300
@@ -5,4 +5,5 @@
[ilog2(0x00000010) + 1] = "T_SYMLINKS",
[ilog2(0x00000020) + 1] = "T_AUTOMOUNTS",
[ilog2(0x00000040) + 1] = "T_EMPTY_PATH",
+ [ilog2(0x00000100) + 1] = "SET_GROUP",
};
$
So now one can use it in --filter expressions for tracepoints.
This silences this perf build warnings:
Warning: Kernel ABI header at 'tools/include/uapi/linux/mount.h' differs from latest version at 'include/uapi/linux/mount.h'
diff -u tools/include/uapi/linux/mount.h include/uapi/linux/mount.h
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick the changes in:
433c38f40f ("arm64: mte: change ASYNC and SYNC TCF settings into bitfields")
e893bb1bb4 ("x86, prctl: Hook L1D flushing in via prctl")
That don't result in any changes in tooling:
$ tools/perf/trace/beauty/prctl_option.sh > before
$ cp include/uapi/linux/prctl.h tools/include/uapi/linux/prctl.h
$ tools/perf/trace/beauty/prctl_option.sh > after
$ diff -u before after
$
Just silences this perf tools build warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/prctl.h' differs from latest version at 'include/uapi/linux/prctl.h'
diff -u tools/include/uapi/linux/prctl.h include/uapi/linux/prctl.h
Cc: Balbir Singh <sblbir@amazon.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Picking the changes from:
81be109349 ("ALSA: pcm: Add SNDRV_PCM_INFO_EXPLICIT_SYNC flag")
Which entails no changes in the tooling side as it doesn't introduce new
ioctls.
To silence this perf tools build warning:
Warning: Kernel ABI header at 'tools/include/uapi/sound/asound.h' differs from latest version at 'include/uapi/sound/asound.h'
diff -u tools/include/uapi/sound/asound.h include/uapi/sound/asound.h
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
