This option is per process anyway. I'd like to add more options, but
having them as parameters of __sanitizer_symbolize_code looks
inconvenient.
Reviewed By: browneee
Differential Revision: https://reviews.llvm.org/D116201
This will allow linking in the callbacks directly instead of using PLT.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D116182
After D116148 the memccpy gets optimized away and the expected
uninitialized memory access does not occur.
Make sure the call does not get optimized away.
The new tsan runtime has 2x more compact shadow.
Adjust shadow ranges accordingly.
Depends on D112603.
Reviewed By: vitalybuka, melver
Differential Revision: https://reviews.llvm.org/D113751
If there are multiple processes, it's hard to understand
what output comes from what process.
VReport prepends pid to the output. Use it.
Depends on D113982.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D113983
Update now after long operations so that we don't use
stale value in subsequent computations.
Depends on D113981.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D113982
Creating threads after a multi-threaded fork is semi-supported,
we don't give particular guarantees, but we try to not fail
on simple cases and we have die_after_fork=0 flag that enables
not dying on creation of threads after a multi-threaded fork.
This flag is used in the wild:
23c052e3e3/SConstruct (L3599)
fork_multithreaded.cpp test started hanging in debug mode
after the recent "tsan: fix deadlock during race reporting" commit,
which added proactive ThreadRegistryLock check in SlotLock.
But the test broke earlier after "tsan: remove quadratic behavior in pthread_join"
commit which made tracking of alive threads based on pthread_t stricter
(CHECK-fail on 2 threads with the same pthread_t, or joining a non-existent thread).
When we start a thread after a multi-threaded fork, the new pthread_t
can actually match one of existing values (for threads that don't exist anymore).
Thread creation started CHECK-failing on this, but the test simply
ignored this CHECK failure in the child thread and "passed".
But after "tsan: fix deadlock during race reporting" the test started hanging dead,
because CHECK failures recursively lock thread registry.
Fix this purging all alive threads from thread registry on fork.
Also the thread registry mutex somehow lost the internal deadlock detector id
and was excluded from deadlock detection. If it would have the id, the CHECK
wouldn't hang because of the nested CHECK failure due to the deadlock.
But then again the test would have silently ignore this error as well
and the bugs wouldn't have been noticed.
Add the deadlock detector id to the thread registry mutex.
Also extend the test to check more cases and detect more bugs.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D116091
If we miss both close of a file descriptor and a subsequent open
if the same file descriptor number, we report false positives
between operations on the old and on the new descriptors.
There are lots of ways to create new file descriptors, but for closing
there is mostly close call. So we try to handle at least it.
However, if the close happens in an ignored library, we miss it
and start reporting false positives.
Handle closing of file descriptors always, even in ignored libraries
(as we do for malloc/free and other critical functions).
But don't imitate memory accesses on close for ignored libraries.
FdClose checks validity of the fd (fd >= 0) itself,
so remove the excessive checks in the callers.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D116095
We used to use u64 as mutex id because it was some
tricky identifier built from address and reuse count.
Now it's just the mutex index in the report (0, 1, 2...),
so use int to represent it.
Depends on D112603.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D113980
These callbacks are used for SSE vector accesses.
In some computational programs these accesses dominate.
Currently we do 2 uninlined 8-byte accesses to handle them.
Inline and optimize them similarly to unaligned accesses.
This reduces the vector access benchmark time from 8 to 3 seconds.
Depends on D112603.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D114594
This also makes the sanitizer_stoptheworld_test cross-platform by using the STL, rather than pthread.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D115204
This attempts to adjust the test to still exercise the expected codepath after D115904. This test is fundementally rather fragile.
Unfortunately, I have not been able to confirm this workaround either does, or does not, work. Attempting check-all with compiler-rt blows through an additional 30GB of disk space so my build config which exceeds my local disk space.
There is a small chance that the slot may be not queued in TraceSwitchPart.
This can happen if the slot has kEpochLast epoch and another thread
in FindSlotAndLock discovered that it's exhausted and removed it from
the slot queue. kEpochLast can happen in 2 cases: (1) if TraceSwitchPart
was called with the slot locked and epoch already at kEpochLast,
or (2) if we've acquired a new slot in SlotLock in the beginning
of the function and the slot was at kEpochLast - 1, so after increment
in SlotAttachAndLock it become kEpochLast.
If this happens we crash on ctx->slot_queue.Remove(thr->slot).
Skip the requeueing if the slot is not queued.
The slot is exhausted, so it must not be ctx->slot_queue.
The existing stress test triggers this with very small probability.
I am not sure how to make this condition more likely to be triggered,
it evaded lots of testing.
Depends on D116040.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D116041
SlotPairLocker calls SlotLock under ctx->multi_slot_mtx.
SlotLock can invoke global reset DoReset if we are out of slots/epochs.
But DoReset locks ctx->multi_slot_mtx as well, which leads to deadlock.
Resolve the deadlock by removing SlotPairLocker/multi_slot_mtx
and only lock one slot for which we will do RestoreStack.
We need to lock that slot because RestoreStack accesses the slot journal.
But it's unclear why we need to lock the current slot.
Initially I did it just to be on the safer side (but at that time
we dit not lock the second slot, so it was easy just to lock the current slot).
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D116040
Profile merging is not supported when using debug info profile
correlation because the data section won't be in the binary at runtime.
Change the default profile name in this mode to `default_%p.proflite` so
we don't use profile merging.
Reviewed By: kyulee
Differential Revision: https://reviews.llvm.org/D115979
Previously we would crash in the TSan runtime if the user program passes
a pointer to `malloc_size()` that doesn't point into app memory.
In these cases, `malloc_size()` should return 0.
For ASan, we fixed a similar issue here:
https://reviews.llvm.org/D15008
Radar-Id: rdar://problem/86213149
Differential Revision: https://reviews.llvm.org/D115947
There was a build failure on the `instrprof-debug-info-correlate.c` test
because zlib was missing so we need to require it to run the test.
Differential Revision: https://reviews.llvm.org/D115970
Extend `llvm-profdata` to read in a `.proflite` file and also a debug info file to generate a normal `.profdata` profile. This reduces the binary size by 8.4% when building an instrumented Clang binary without value profiling (164 MB vs 179 MB).
This work is part of the "lightweight instrumentation" RFC: https://groups.google.com/g/llvm-dev/c/r03Z6JoN7d4
This was first landed in https://reviews.llvm.org/D114566 but had to be reverted due to build errors.
Reviewed By: kyulee
Differential Revision: https://reviews.llvm.org/D115915
This reverts commit 3f5f687e2e.
That commit broke building for mingw, where the sanitizers are
built with -nostdinc++, while the added source file includes
the C++ standard library's <algorithm>.
Additionally, the new code fails to build for i386, as it
unconditionally uses the CONTEXT member Rsp.
AARCH64_GET_REG() is used to initialize uptrs, and after D79132
the ptrauth branch of its implementation explicitly casts to uptr.
The non-ptrauth branch returns ucontext->uc_mcontext->__ss.__fp (etc),
which has either type void* or __uint64_t (ref usr/include/mach/arm/_structs.h)
where __uint64_t is a unsigned long long (ref usr/include/arm/_types.h).
uptr is an unsigned long (ref
compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h). So explicitly
cast to uptr in this branch as well, so that AARCH64_GET_REG() has a
well-defined type.
Then change DUMPREGA64() tu use %lx instead of %llx since that's the right type
for uptr. (Most other places in compiler-rt print uptrs as %p and cast the arg
to (void*), but there are explicit 0x%016 format strings in the surroundings,
so be locally consistent with that.)
No behavior change, in the end it's just 64-bit unsigneds by slightly different
names.
This also makes the sanitizer_stoptheworld_test cross-platform by using the STL, rather than pthread.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D115204
Extend `llvm-profdata` to read in a `.proflite` file and also a debug info file to generate a normal `.profdata` profile. This reduces the binary size by 8.4% when building an instrumented Clang binary without value profiling (164 MB vs 179 MB).
This work is part of the "lightweight instrumentation" RFC: https://groups.google.com/g/llvm-dev/c/r03Z6JoN7d4
Reviewed By: kyulee
Differential Revision: https://reviews.llvm.org/D114566
Add the llvm flag `-debug-info-correlate` to attach debug info to instrumentation counters so we can correlate raw profile data to their functions. Raw profiles are dumped as `.proflite` files. The next diff enables `llvm-profdata` to consume `.proflite` and debug info files to produce a normal `.profdata` profile.
Part of the "lightweight instrumentation" work: https://groups.google.com/g/llvm-dev/c/r03Z6JoN7d4
The original diff https://reviews.llvm.org/D114565 was reverted because of the `Instrumentation/InstrProfiling/debug-info-correlate.ll` test, which is fixed in this commit.
Reviewed By: kyulee
Differential Revision: https://reviews.llvm.org/D115693
There were changes made to the linux version of this test that were not made for darwin
(see https://reviews.llvm.org/D115837) and this caused downstream failures.
Adding comment to this test to remind people to edit interface_symbols_darwin.cpp.
There is the reverse of this comment in the darwin file to remind us to edit the linux version already.
Differential Revision: https://reviews.llvm.org/D115899
LSan (`ASAN_OPTIONS=detect_leaks=1`) is supported on macOS, but disabled
by default on Darwin (`SANITIZER_MAC`):
```
COMMON_FLAG(bool, detect_leaks, !SANITIZER_MAC, "Enable memory leak detection.")
```
We enable it here for ASan tests to prevent regressions (per comment).
However, LSan is not supported for the iOS simulator and the tests fail
when it is enabled.
Make this "Is macOS?" check more precise since the current one (`Darwin
&& x86_64`) has two issues:
* Includes the simulators
* Excludes macOS on Apple Silicon
This will allow us to (re)enable simulator testing on Green dragon to
give open source better feedback about sanitizer changes:
https://green.lab.llvm.org
rdar://86529234
Differential Revision: https://reviews.llvm.org/D115816
This test would hang when the system ran out of resources and we fail to
create all 300 threads.
Differential Revision: https://reviews.llvm.org/D115845
In the new TSan runtime refactoring this line was changed:
```
ProtectRange(MetaShadowEnd(), TraceMemBeg());
-->
ProtectRange(MetaShadowEnd(), HeapMemBeg());
```
But for `MappingAppleAarch64` the app heap comes before the shadow,
resulting in:
```
CHECK failed: tsan_platform_posix.cpp:83 "((beg)) <= ((end))" (0xe00000000, 0x200000000)
```
rdar://86521924
Differential Revision: https://reviews.llvm.org/D115834
A while ago we added some code to the sanitizer runtimes for iOS
simulators to allow `atos` (external process) to inspect the sanitized
process during report generation to enable symbolication. This was done
by setting the `__check_mach_ports_lookup` env var early during process
startup which came with a couple of complications.
This workaround is not required anymore and removing it fixes TSan in
the iOS simulator after the new TSan runtime landed.
(https://reviews.llvm.org/D112603)
Relevant/reverted revisions:
https://reviews.llvm.org/D78178https://reviews.llvm.org/D78179https://reviews.llvm.org/D78525
rdar://86472733
Differential Revision: https://reviews.llvm.org/D115767
Adds -L<search-path> and -l<library> options that are analogous to ld's
versions.
Each instance of -L<search-path> or -l<library> will apply to the most recent
-jd option on the command line (-jd <name> creates a JITDylib with the given
name). Library names will match against JITDylibs first, then llvm-jitlink will
look through the search paths for files named <search-path>/lib<library>.dylib
or <search-path>/lib<library>.a.
The default "main" JITDylib will link against all JITDylibs created by -jd
options, and all JITDylibs will link against the process symbols (unless
-no-process-symbols is specified).
The -dlopen option is renamed -preload, and will load dylibs into the JITDylib
for the ORC runtime only.
The effect of these changes is to make it easier to describe a non-trivial
program layout to llvm-jitlink for testing purposes. E.g. the following
invocation describes a program consisting of three JITDylibs: "main" (created
implicitly) containing main.o, "Foo" containing foo1.o and foo2.o, and linking
against library "bar" (not a JITDylib, so it must be a .dylib or .a on disk)
and "Baz" (which is a JITDylib), and "Baz" containing baz.o.
llvm-jitlink \
main.o \
-jd Foo foo1.o foo2.o -L${HOME}/lib -lbar -lBaz
-jd Baz baz.o
This is present in our assembly files. It should fix decorate_proc_maps.cpp failures because of shadow memory being allocated as executable.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D115552
This change moves optimized callbacks from each .o file to compiler-rt. Instead of using code generation it uses direct assembly implementation. Please note that the 'or' version is not implemented and it will produce unresolved external if somehow 'or' version is requested.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D114558
This reverts commit 800bf8ed29.
The `Instrumentation/InstrProfiling/debug-info-correlate.ll` test was
failing because I forgot the `llc` commands are architecture specific.
I'll follow up with a fix.
Differential Revision: https://reviews.llvm.org/D115689
Add the llvm flag `-debug-info-correlate` to attach debug info to instrumentation counters so we can correlate raw profile data to their functions. Raw profiles are dumped as `.proflite` files. The next diff enables `llvm-profdata` to consume `.proflite` and debug info files to produce a normal `.profdata` profile.
Part of the "lightweight instrumentation" work: https://groups.google.com/g/llvm-dev/c/r03Z6JoN7d4
Reviewed By: kyulee
Differential Revision: https://reviews.llvm.org/D114565
Adds a fallback to use the debuginfod client library (386655) in `findDebugBinary`.
Fixed a cast of Erorr::success() to Expected<> in debuginfod library.
Added Debuginfod to Symbolize deps in gn.
Updates compiler-rt/lib/sanitizer_common/symbolizer/scripts/build_symbolizer.sh to include Debuginfod library to fix sanitizer-x86_64-linux breakage.
Reviewed By: jhenderson, vitalybuka
Differential Revision: https://reviews.llvm.org/D113717
This change switches tsan to the new runtime which features:
- 2x smaller shadow memory (2x of app memory)
- faster fully vectorized race detection
- small fixed-size vector clocks (512b)
- fast vectorized vector clock operations
- unlimited number of alive threads/goroutimes
Depends on D112602.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D112603
Currently the test calls dlclose in the thread
concurrently with the main thread calling a function
from the dynamic library. This is not good.
Wait for the main thread to call the function
before calling dlclose.
Depends on D115612.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D115613
The test contains a race and checks that it's detected.
But the race may not be detected since we are doing aggressive flushes
and if the state flush happens between racing accesses, tsan won't
detect the race). So return 1 to make the test deterministic
regardless of the race.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D115612
This is present in our assembly files. It should fix decorate_proc_maps.cpp failures because of shadow memory being allocated as executable.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D115552
This change moves optimized callbacks from each .o file to compiler-rt. Instead of using code generation it uses direct assembly implementation. Please note that the 'or' version is not implemented and it will produce unresolved external if somehow 'or' version is requested.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D114558
Adds x-ray support for hexagon to llvm codegen, clang driver,
compiler-rt libs.
Differential Revision: https://reviews.llvm.org/D113638
Reapplying this after 543a9ad7c4,
which fixes the leak introduced there.
Adds a fallback to use the debuginfod client library (386655) in `findDebugBinary`.
Fixed a cast of Erorr::success() to Expected<> in debuginfod library.
Added Debuginfod to Symbolize deps in gn.
Updates compiler-rt/lib/sanitizer_common/symbolizer/scripts/build_symbolizer.sh to include Debuginfod library to fix sanitizer-x86_64-linux breakage.
Reviewed By: jhenderson, vitalybuka
Differential Revision: https://reviews.llvm.org/D113717
Adds a fallback to use the debuginfod client library (386655) in `findDebugBinary`.
Fixed a cast of Erorr::success() to Expected<> in debuginfod library.
Added Debuginfod to Symbolize deps in gn.
Adds new symbolizer symbols to `global_symbols.txt`.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D113717
This change moves optimized callbacks from each .o file to compiler-rt. Instead of using code generation it uses direct assembly implementation. Please note that the 'or' version is not implemented and it will produce unresolved external if somehow 'or' version is requested.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D114558
The test has been flaky for years, and I think we should remove it to
eliminate noise on the buildbot.
Neither me nor dokyungs have been able to fully deflake the test, and it
tests a non-default Entropic flag.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D115453
This removes the last use of StackDepot from StopTheWorld.
Depends on D115284.
Reviewed By: morehouse
Differential Revision: https://reviews.llvm.org/D115319
StackDepot locks some stuff. As is there is small probability to
deadlock if we stop thread which locked the Depot.
We need either Lock/Unlock StackDepot for StopTheWorld, or don't
interact with StackDepot from there.
This patch does not run LeakReport under StopTheWorld. LeakReport
contains most of StackDepot access.
As a bonus this patch will help to resolve kMaxLeaksConsidered FIXME.
Depends on D114498.
Reviewed By: morehouse, kstoimenov
Differential Revision: https://reviews.llvm.org/D115284
This reverts commit e5c2a46c5e as this
change introduced a linker error when building sanitizer runtimes:
ld.lld: error: undefined symbol: __sanitizer::internal_start_thread(void* (*)(void*), void*)
>>> referenced by sanitizer_stackdepot.cpp:133 (compiler-rt/lib/sanitizer_common/sanitizer_stackdepot.cpp:133)
>>> compiler-rt/lib/sanitizer_common/CMakeFiles/RTSanitizerCommonSymbolizer.x86_64.dir/sanitizer_stackdepot.cpp.obj:(__sanitizer::(anonymous namespace)::CompressThread::NewWorkNotify())
This change switches tsan to the new runtime which features:
- 2x smaller shadow memory (2x of app memory)
- faster fully vectorized race detection
- small fixed-size vector clocks (512b)
- fast vectorized vector clock operations
- unlimited number of alive threads/goroutimes
Depends on D112602.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D112603
Fork the current version of tsan runtime before commiting
rewrite of the runtime (D112603). The old runtime can be
enabled with TSAN_USE_OLD_RUNTIME option.
This is a temporal measure for emergencies and is required
for Chromium rollout (for context see http://crbug.com/1275581).
The old runtime is supposed to be deleted soon.
Reviewed By: thakis
Differential Revision: https://reviews.llvm.org/D115223
This reverts commit 5c27740238.
Reverting due to Windows build issue:
sanitizer_stackdepot.cpp.obj : error LNK2005: "void __cdecl __sanitizer::StackDepotStopBackgroundThread(void)" (?StackDepotStopBackgroundThread@__sanitizer@@YAXXZ) already defined in sanitizer_common_libcdep.cpp.obj
LINK : fatal error LNK1181: cannot open input file 'projects\compiler-rt\lib\asan\CMakeFiles\RTAsan_dynamic.x86_64.dir\asan_rtl_x86_64.S.obj'
This change moves optimized callbacks from each .o file to compiler-rt. Instead of using code generation it uses direct assembly implementation. Please note that the 'or' version is not implemented and it will produce unresolved external if somehow 'or' version is requested.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D114558
Some of the compiler-rt runtimes use custom instrumented libc++ build.
Use the runtimes build for building this custom libc++.
Differential Revision: https://reviews.llvm.org/D114922
We don't run tests or benchmarks from this build anyway.
Benchmarks in custom libc++ break my local build.
Reviewed By: ldionne
Differential Revision: https://reviews.llvm.org/D115375
kIgnored didn't exist when the code was added, but it should be
equivalent to kReachable.
The goal is to refactor MarkInvalidPCCb to avoid StackDepotGet
in StopTheWorld.
Some of the compiler-rt runtimes use custom instrumented libc++ build.
Use the runtimes build for building this custom libc++.
Differential Revision: https://reviews.llvm.org/D114922
It is required for the [Leak Sanitizer port to Windows](https://reviews.llvm.org/D115103).
The currently used `unsigned long` type is 64 bits wide on UNIX like systems but only 32 bits wide on Windows.
Because of that, the literal `8UL << 30` causes an integer overflow on Windows.
By changing the type of the literals to `unsigned long long`, we have consistent behavior and no overflows on all Platforms.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D115186
That way, the build rules are closer to the source files they describe.
No intended behavior change.
Differential Revision: https://reviews.llvm.org/D115155
Building xray with recent clang on a 64-bit system results in a number
of -Wformat warnings:
compiler-rt/lib/xray/xray_allocator.h:70:11: warning: format specifies type 'int' but the argument has type '__sanitizer::uptr' (aka 'unsigned long') [-Wformat]
RoundedSize, B);
^~~~~~~~~~~
compiler-rt/lib/xray/xray_allocator.h:119:11: warning: format specifies type 'int' but the argument has type '__sanitizer::uptr' (aka 'unsigned long') [-Wformat]
RoundedSize, B);
^~~~~~~~~~~
Since `__sanitizer::uptr` has the same size as `size_t`, these can be
fixed by using the printf specifier `%zu`.
compiler-rt/lib/xray/xray_basic_logging.cpp:348:46: warning: format specifies type 'int' but the argument has type '__sanitizer::tid_t' (aka 'unsigned long long') [-Wformat]
Report("Cleaned up log for TID: %d\n", GetTid());
~~ ^~~~~~~~
%llu
compiler-rt/lib/xray/xray_basic_logging.cpp:353:62: warning: format specifies type 'int' but the argument has type '__sanitizer::tid_t' (aka 'unsigned long long') [-Wformat]
Report("Skipping buffer for TID: %d; Offset = %llu\n", GetTid(),
~~ ^~~~~~~~
%llu
Since `__sanitizer::tid_t` is effectively declared as `unsigned long
long`, these can be fixed by using the printf specifier `%llu`.
compiler-rt/lib/xray/xray_basic_logging.cpp:354:14: warning: format specifies type 'unsigned long long' but the argument has type 'size_t' (aka 'unsigned long') [-Wformat]
TLD.BufferOffset);
^~~~~~~~~~~~~~~~
Since `BufferOffset` is declared as `size_t`, this one can be fixed by
using `%zu` as a printf specifier.
compiler-rt/lib/xray/xray_interface.cpp:172:50: warning: format specifies type 'int' but the argument has type 'uint64_t' (aka 'unsigned long') [-Wformat]
Report("Unsupported sled kind '%d' @%04x\n", Sled.Address, int(Sled.Kind));
~~ ^~~~~~~~~~~~
%lu
Since ``xray::SledEntry::Address` is declared as `uint64_t`, this one
can be fixed by using `PRIu64`, and adding `<cinttypes>`.
compiler-rt/lib/xray/xray_interface.cpp:308:62: warning: format specifies type 'long long' but the argument has type 'size_t' (aka 'unsigned long') [-Wformat]
Report("System page size is not a power of two: %lld\n", PageSize);
~~~~ ^~~~~~~~
%zu
compiler-rt/lib/xray/xray_interface.cpp:359:64: warning: format specifies type 'long long' but the argument has type 'size_t' (aka 'unsigned long') [-Wformat]
Report("Provided page size is not a power of two: %lld\n", PageSize);
~~~~ ^~~~~~~~
%zu
Since `PageSize` is declared as `size_t`, these can be fixed by using
`%zu` as a printf specifier.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D114469
Vitaly Buka