Some architectures (mips) require libatomic to support proper
atomic operations. Check first if support is available without
linking, otherwise use the library.
Contributors:
James Cowgill <jcowgill@debian.org>
Jessica Clarke <jrtc27@debian.org>
Vicențiu Ciorbaru <vicentiu@mariadb.org>
Create minidump when server fails to shutdown. If process is being
debugged, cause a debug break.
Moves some code which is part of safe_kill into mysys, as both safe_kill,
and mysqltest produce minidumps on different timeouts.
Small cleanup in wait_until_dead() - replace inefficient loop with a single
wait.
init_mutex_v1_t: Stop lying that the mutex parameter is const.
GCC 11.2.0 assumes that it is and could complain about any mysql_mutex_t
being uninitialized even after mysql_mutex_init() as long as
PLUGIN_PERFSCHEMA is enabled.
init_rwlock_v1_t, init_cond_v1_t: Remove untruthful const qualifiers.
Note: init_socket_v1_t is expecting that the socket fd has already
been created before PSI_SOCKET_CALL(init_socket), and therefore that
parameter really is being treated as a pointer to const.
It seems some overly tolerant compilers (gcc) allow the structure
of IO_CACHE that is defined differently in libmaria to have
members equalivance to the iocache in mysys.
More strict Solaris compilers recognise that rc_pos really
isn't a structure member and won't compile.
The reason for the crash was that there was not a write lock to
protect against file rotations in the server_audit plugin after an
audit plugin patch to changed audit mutexes to read & write locks.
The fixes are:
* Moving server_audit.c to use read & write locks (which improves
performance).
* Added functionality in file_logger.c to not do file rotations until
it is allowed by the caller (done without any interface changes for
the logging service).
* Move checking of file size limit to server_audit.c and if it is time to
do a rotation change the read lock to a write lock and tell file_logger
that it is now allowed to rotate the log files.
volatile != atomic.
volatile has no memory barrier schemantics, its for mmaped IO
so lets allow some optimizer gains and stop pretending it helps
with memory atomicity.
The MDEV lists a SEGV an assumption is made that an address was
partially read. As C packs structs strictly in order and on arm64 the
cache line size is 128 bits. A pointer (link - 64 bits), followed
by a hashnr (uint32 - 32 bits), leaves the following key (uchar *
64 bits), neither naturally aligned to any pointer and worse, split
across a cache line which is the processors view of an atomic
reservation of memory.
lf_dynarray_lvalue is assumed to return a 64 bit aligned address.
As a solution move the 32bit hashnr to the end so we don't get the
*key pointer split across two cache lines.
Tested by: Krunal Bauskar
Reviewer: Marko Mäkelä
Encountered the linker failure on Debug build in 10.4:
[53/585] Linking CXX executable unittest/sql/mf_iocache-t
FAILED: unittest/sql/mf_iocache-t
: && /usr/bin/c++ -pie -fPIC -fstack-protector --param=ssp-buffer-size=4 -fPIC -g -DENABLED_DEBUG_SYNC -ggdb3 -DSAFE_MUTEX -DSAFEMALLOC -DTRASH_FREED_MEMORY -Wall -Wextra -Wno-format-truncation -Wno-init-self -Wno-nonnull-compare -Wno-unused-parameter -Woverloaded-virtual -Wnon-virtual-dtor -Wvla -Wwrite-strings -Werror -Wl,-z,relro,-z,now unittest/sql/CMakeFiles/mf_iocache-t.dir/mf_iocache-t.cc.o unittest/sql/CMakeFiles/mf_iocache-t.dir/__/__/sql/mf_iocache_encr.cc.o -o unittest/sql/mf_iocache-t -lpthread mysys/libmysys.a unittest/mytap/libmytap.a mysys_ssl/libmysys_ssl.a mysys/libmysys.a dbug/libdbug.a mysys/libmysys.a dbug/libdbug.a -lz -lm strings/libstrings.a -lpthread -lssl -lcrypto -ldl && :
/usr/bin/ld: mysys/libmysys.a(my_addr_resolve.c.o):/home/dan/repos/mariadb-server-10.4/mysys/my_addr_resolve.c:173: multiple definition of `info'; unittest/sql/CMakeFiles/mf_iocache-t.dir/mf_iocache-t.cc.o:/home/dan/repos/mariadb-server-10.4/unittest/sql/mf_iocache-t.cc:99: first defined here
We make Dl_info static as in MDEV-21646 moving it out of the function
was the main goal and having it scope limited by static doesn't affect
the function.
This follows up commit
commit 94a520ddbe and
commit 7c5519c12d.
After these changes, the default test suites on a
cmake -DWITH_UBSAN=ON build no longer fail due to passing
null pointers as parameters that are declared to never be null,
but plenty of other runtime errors remain.
According to https://stackoverflow.com/questions/22827510/how-to-avoid-bad-fd-set-buffer-overflow-crash
it seems that using select instead of poll can cause additional memory
allocations. As we are in a crashed state, we must prevent allocating
any memory (if possible). Thus, switch select call to poll.
Also move some bigger datastructures to global space. The code is not
run in a multithreaded context so best we don't use up stack space
if it's not needed.
There are 2 issues here:
Issue #1: memory allocation.
An IO_CACHE that uses encryption uses a larger buffer (it needs space for the encrypted data,
decrypted data, IO_CACHE_CRYPT struct to describe encryption parameters etc).
Issue #2: IO_CACHE::seek_not_done
When IO_CACHE objects are cloned, they still share the file descriptor.
This means, operation on one IO_CACHE may change the file read position
which will confuse other IO_CACHEs using it.
The fix of these issues would be:
Allocate the buffer to also include the extra size needed for encryption.
Perform seek again after one IO_CACHE reads the file.
The presumed reason for the error is that the file was opened
by 3rd party antivirus or backup program, causing ERROR_SHARING_VIOLATION
on rename.
The fix, actually a workaround, is to retry MoveFileEx couple of times
before finally giving up. We expect 3rd party programs not to hold file
for extended time.
Passing a null pointer to a nonnull argument is not only undefined
behaviour, but it also grants the compiler the permission to optimize
away further checks whether the pointer is null. GCC -O2 at least
starting with version 8 may do that, potentially causing SIGSEGV.
These problems were caught in a WITH_UBSAN=ON build with the
Bug#7024 test in main.view.
depending on build config the error might be hidded,
in particular liblz4.so and libjemalloc.so make it to disappear,
but with -DWITH_INNODB_LZ4=NO -DWITH_JEMALLOC=NO it reappears.
I run perf top during ./mtr testing and constantly see times()
function there. It's so slow, that it has no sense to run it
in a loop too many times.
This patch speeds up -suite=innodb for me from 218s to 208s.
9s of times() function!
Largely based on MySQL commit
75271e51d6
MySQL Ref:
BUG#24566529: BACKPORT BUG#23575445 TO 5.6
(cut)
Also, the PTR_SANE macro which tries to check if a pointer
is invalid (used when printing pointer values in stack traces)
gave false negatives on OSX/FreeBSD. On these platforms we
now simply check if the pointer is non-null. This also removes
a sbrk() deprecation warning when building on OS X. (It was
before only disabled with building using XCode).
Removed execinfo path of MySQL patch that was already included.
sbrk doesn't exist on FreeBSD aarch64.
Removed HAVE_BSS_START based detection and replaced with __linux__
as it doesn't exist on OSX, Solaris or Windows. __bss_start
exists on mutiple Linux architectures.
Tested on FreeBSD and Linux x86_64. Being in FreeBSD ports for 2
years implies a good testing there on all FreeBSD architectures there
too. MySQL-8.0.21 code is functionally identical to original commit.
