Commit Graph

12 Commits

Author SHA1 Message Date
Thomas Huth 7aa12aa215 Remove the CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE switch
GCC supports "#pragma GCC diagnostic" since version 4.6, and
Clang seems to support it, too, since its early versions 3.x.
That means that our minimum required compiler versions all support
this pragma already and we can remove the test from configure and
all the related #ifdefs in the code.

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20200710045515.25986-1-thuth@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-13 11:40:52 +02:00
Robert Foley 995f5c3c32 util/coroutine: Cleanup start_switch_fiber_ for TSAN.
This is a cleanup patch to follow-up the patch which introduced TSAN.
This patch makes separate start_switch_fiber_ functions for TSAN and ASAN.

This does two things:
1. Unrelated ASAN and TSAN code is separate and each function only
   has arguments that are actually needed.
2. The co->tsan_caller_fiber and co->tsan_co_fiber fields are only
   access from within #ifdef CONFIG_TSAN.

Signed-off-by: Robert Foley <robert.foley@linaro.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200626170001.27017-1-robert.foley@linaro.org>
Message-Id: <20200701135652.1366-5-alex.bennee@linaro.org>
2020-07-11 15:52:59 +01:00
Daniele Buono 58ebc2c313 coroutine: support SafeStack in ucontext backend
LLVM's SafeStack instrumentation does not yet support programs that make
use of the APIs in ucontext.h
With the current implementation of coroutine-ucontext, the resulting
binary is incorrect, with different coroutines sharing the same unsafe
stack and producing undefined behavior at runtime.
This fix allocates an additional unsafe stack area for each coroutine,
and sets the new unsafe stack pointer before calling swapcontext() in
qemu_coroutine_new.
This is the only place where the pointer needs to be manually updated,
since sigsetjmp/siglongjmp are already instrumented by LLVM to properly
support SafeStack.
The additional stack is then freed in qemu_coroutine_delete.

Signed-off-by: Daniele Buono <dbuono@linux.vnet.ibm.com>
Message-id: 20200529205122.714-2-dbuono@linux.vnet.ibm.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2020-06-23 15:46:05 +01:00
Lingfeng Yang 0aebab04b9 configure: add --enable-tsan flag + fiber annotations for coroutine-ucontext
We tried running QEMU under tsan in 2016, but tsan's lack of support for
longjmp-based fibers was a blocker:
  https://groups.google.com/forum/#!topic/thread-sanitizer/se0YuzfWazw

Fortunately, thread sanitizer gained fiber support in early 2019:
  https://reviews.llvm.org/D54889

This patch brings tsan support upstream by importing the patch that annotated
QEMU's coroutines as tsan fibers in Android's QEMU fork:
  https://android-review.googlesource.com/c/platform/external/qemu/+/844675

Tested with '--enable-tsan --cc=clang-9 --cxx=clang++-9 --disable-werror'
configure flags.

Signed-off-by: Lingfeng Yang <lfy@google.com>
Signed-off-by: Emilio G. Cota <cota@braap.org>
[cota: minor modifications + configure changes]
Signed-off-by: Robert Foley <robert.foley@linaro.org>
[RF: configure changes, coroutine fix + minor modifications]
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200609200738.445-2-robert.foley@linaro.org>
Message-Id: <20200612190237.30436-5-alex.bennee@linaro.org>
2020-06-16 14:49:05 +01:00
Markus Armbruster a8d2532645 Include qemu-common.h exactly where needed
No header includes qemu-common.h after this commit, as prescribed by
qemu-common.h's file comment.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-5-armbru@redhat.com>
[Rebased with conflicts resolved automatically, except for
include/hw/arm/xlnx-zynqmp.h hw/arm/nrf51_soc.c hw/arm/msf2-soc.c
block/qcow2-refcount.c block/qcow2-cluster.c block/qcow2-cache.c
target/arm/cpu.h target/lm32/cpu.h target/m68k/cpu.h target/mips/cpu.h
target/moxie/cpu.h target/nios2/cpu.h target/openrisc/cpu.h
target/riscv/cpu.h target/tilegx/cpu.h target/tricore/cpu.h
target/unicore32/cpu.h target/xtensa/cpu.h; bsd-user/main.c and
net/tap-bsd.c fixed up]
2019-06-12 13:20:20 +02:00
Gerd Hoffmann 0e39c4aa7e build: try improve handling of clang warnings
This patch disables the pragma diagnostic -Wunused-but-set-variable for
clang in util/coroutine-ucontext.c.

This in turn allows us to remove it from the configure check, so the
CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE will succeed for clang.

With that in place clang builds (linux) will use -Werror by default,
which breaks the build due to warning about unaligned struct members.

Just turning off this warning isn't a good idea as it indicates
portability problems.  So make it a warning again, using
-Wno-error=address-of-packed-member.  That way it doesn't break the
build but still shows up in the logs.

Now clang builds qemu without errors.  Well, almost.  There are some
left in the rdma code.  Leaving that to the rdma people.  All others can
use --disable-rdma to workarounds this.

Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-Id: <20180309135945.20436-1-kraxel@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2018-03-12 08:59:03 +01:00
Marc-André Lureau d83414e1fd ucontext: annotate coroutine stack for ASAN
It helps ASAN to detect more leaks on coroutine stacks, and to get rid
of some extra warnings.

Before:

tests/test-coroutine -p
/basic/lifecycle
/basic/lifecycle: ==20781==WARNING: ASan doesn't fully support
makecontext/swapcontext functions and may produce false positives in
some cases!
==20781==WARNING: ASan is ignoring requested __asan_handle_no_return:
stack top: 0x7ffcb184d000; bottom 0x7ff6c4cfd000; size: 0x0005ecb50000
(25446121472)
False positive error reports may follow
For details see https://github.com/google/sanitizers/issues/189
OK

After:

tests/test-coroutine -p /basic/lifecycle
/basic/lifecycle: ==21110==WARNING: ASan doesn't fully support
makecontext/swapcontext functions and may produce false positives in
some cases!
OK

A similar work would need to be done for sigaltstack & windows fibers
to have similar coverage. Since ucontext is preferred, I didn't bother
checking the other coroutine implementations for now.

Update travis to fix the build with ASAN annotations.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180116151152.4040-4-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-02-07 14:09:24 +01:00
Peter Lieven ddba15919b coroutine-ucontext: use helper for allocating stack memory
Signed-off-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-29 14:13:39 +02:00
Peter Lieven 8adcd6fb6d coroutine: add a macro for the coroutine stack size
Signed-off-by: Peter Lieven <pl@kamp.de>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-09-29 14:13:39 +02:00
Stefan Weil 8ff98f1ed2 Remove unneeded include statements for setjmp.h
As soon as setjmp.h is included from qemu/osdep.h, those old include
statements are no longer needed.

Add also setjmp.h to the list in scripts/clean-includes.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
2016-03-22 19:11:15 +01:00
Peter Maydell aafd758410 util: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1454089805-5470-6-git-send-email-peter.maydell@linaro.org
2016-02-04 17:01:04 +00:00
Daniel P. Berrange 10817bf09d coroutine: move into libqemuutil.a library
The coroutine files are currently referenced by the block-obj-y
variable. The coroutine functionality though is already used by
more than just the block code. eg migration code uses coroutine
yield. In the future the I/O channel code will also use the
coroutine yield functionality. Since the coroutine code is nicely
self-contained it can be easily built as part of the libqemuutil.a
library, making it widely available.

The headers are also moved into include/qemu, instead of the
include/block directory, since they are now part of the util
codebase, and the impl was never in the block/ directory
either.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-10-20 14:59:04 +01:00