We were mistakenly checking tcg_ctx->plugin_insn as a canary to know
whether the TB had emitted helpers that might have accessed memory.
The problem is that tcg_ctx->plugin_insn gets updated on every
instruction in the TB, which results in us wrongly performing the
optimization (i.e. not clearing cpu->plugin_mem_cbs) way too often,
since it's not rare that the last instruction in the TB doesn't
use helpers.
Fix it by tracking a per-TB canary.
While at it, expand documentation.
Related: #1381
Signed-off-by: Emilio Cota <cota@braap.org>
Message-Id: <20230108164731.61469-2-cota@braap.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-32-alex.bennee@linaro.org>
To fix potential deadlocks as reported by tsan.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Emilio Cota <cota@braap.org>
Message-Id: <20230111151628.320011-6-cota@braap.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-31-alex.bennee@linaro.org>
We forgot to add this one in "a890643958 util/qht: atomically set b->hashes".
Detected with tsan.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio Cota <cota@braap.org>
Message-Id: <20230111151628.320011-3-cota@braap.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-28-alex.bennee@linaro.org>
Fixes the appended use-after-free. The root cause is that
during tb invalidation we use CPU_FOREACH, and therefore
to safely free a vCPU we must wait for an RCU grace period
to elapse.
$ x86_64-linux-user/qemu-x86_64 tests/tcg/x86_64-linux-user/munmap-pthread
=================================================================
==1800604==ERROR: AddressSanitizer: heap-use-after-free on address 0x62d0005f7418 at pc 0x5593da6704eb bp 0x7f4961a7ac70 sp 0x7f4961a7ac60
READ of size 8 at 0x62d0005f7418 thread T2
#0 0x5593da6704ea in tb_jmp_cache_inval_tb ../accel/tcg/tb-maint.c:244
#1 0x5593da6704ea in do_tb_phys_invalidate ../accel/tcg/tb-maint.c:290
#2 0x5593da670631 in tb_phys_invalidate__locked ../accel/tcg/tb-maint.c:306
#3 0x5593da670631 in tb_invalidate_phys_page_range__locked ../accel/tcg/tb-maint.c:542
#4 0x5593da67106d in tb_invalidate_phys_range ../accel/tcg/tb-maint.c:614
#5 0x5593da6a64d4 in target_munmap ../linux-user/mmap.c:766
#6 0x5593da6dba05 in do_syscall1 ../linux-user/syscall.c:10105
#7 0x5593da6f564c in do_syscall ../linux-user/syscall.c:13329
#8 0x5593da49e80c in cpu_loop ../linux-user/x86_64/../i386/cpu_loop.c:233
#9 0x5593da6be28c in clone_func ../linux-user/syscall.c:6633
#10 0x7f496231cb42 in start_thread nptl/pthread_create.c:442
#11 0x7f49623ae9ff (/lib/x86_64-linux-gnu/libc.so.6+0x1269ff)
0x62d0005f7418 is located 28696 bytes inside of 32768-byte region [0x62d0005f0400,0x62d0005f8400)
freed by thread T148 here:
#0 0x7f49627b6460 in __interceptor_free ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:52
#1 0x5593da5ac057 in cpu_exec_unrealizefn ../cpu.c:180
#2 0x5593da81f851 (/home/cota/src/qemu/build/qemu-x86_64+0x484851)
Signed-off-by: Emilio Cota <cota@braap.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230111151628.320011-2-cota@braap.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-27-alex.bennee@linaro.org>
This will be helpful in debugging problems with tracking SVE memory
accesses via the TCG plugins system.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Cc: Robert Henry <robhenry@microsoft.com>
Cc: Aaron Lindsay <aaron@os.amperecomputing.com>
Message-Id: <20230124180127.1881110-26-alex.bennee@linaro.org>
Windows open(2) implementation opens files in text mode by default and
needs a Windows-only O_BINARY flag to open files as binary. QEMU already
knows about that flag in osdep and it is defined to 0 on non-Windows,
so we can just add it to the host_flags for better compatibility.
Signed-off-by: Evgeny Iakovlev <eiakovlev@linux.microsoft.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Message-Id: <20230106102018.20520-1-eiakovlev@linux.microsoft.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-25-alex.bennee@linaro.org>
'lock_user' allocates a host buffer to shadow a target buffer,
'unlock_user' copies that host buffer back to the target and frees the
host memory. If the completion function uses the target buffer, it
must be called after unlock_user to ensure the data are present.
This caused the arm-compatible TARGET_SYS_READC to fail as the
completion function, common_semi_readc_cb, pulled data from the target
buffer which would not have been gotten the console data.
I decided to fix all instances of this pattern instead of just the
console_read function to make things consistent and potentially fix
bugs in other cases.
Signed-off-by: Keith Packard <keithp@keithp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20221012014822.1242170-1-keithp@keithp.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230124180127.1881110-24-alex.bennee@linaro.org>
Drop the frankly misleading quickstart section for a more rounded
introduction section. This new section gives an overview of the
accelerators as well as a high level introduction to some of the key
features of the emulator. We also expand on a general form for a QEMU
command line with a hopefully not too scary worked example of what
this looks like.
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Kashyap Chamarthy <kchamart@redhat.com>
Message-Id: <20230124180127.1881110-23-alex.bennee@linaro.org>
The main reason to do this is to document our O_BINARY implementation
decision somewhere. However I've also moved some of the implementation
details out of qemu-options and added links between the two. As a
bonus I've highlighted the scary warnings about host access with the
appropriate RST tags.
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-22-alex.bennee@linaro.org>
This affects both system and user mode emulation so we should probably
list it up front.
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-21-alex.bennee@linaro.org>
Make it easier to navigate the documentation.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230124180127.1881110-20-alex.bennee@linaro.org>
tests/tcg/nios2/Makefile.target has accidentally been added
to the Microblaze section. Move it into the correct nios2
section instead - and while we're at it, it should also cover
the whole folder, and not only the Makefile.
Fixes: 67f80eb4d0 ("tests/tcg: enable debian-nios2-cross for test building")
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230119130326.2030297-1-thuth@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-19-alex.bennee@linaro.org>
Instead of spewing the whole log to stdout lets just define them as
build artefacts so we can examine them later. Where we are running
check-tcg run it first as those tests are yet to be integrated into
meson. To avoid confusion we don't run multiple check-tcg tests at
once.
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-18-alex.bennee@linaro.org>
linux-user blocks all signals while attempting to handle guest
signals (e.g. ABRT), which means that the default TERM sent by timeout
has no effect -- KILL instead.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230117035701.168514-2-richard.henderson@linaro.org>
[AJB: expanded commit message from cover letter]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230124180127.1881110-17-alex.bennee@linaro.org>
We are getting a lot of failures that are not related to changes so
this could be a flaky test.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-16-alex.bennee@linaro.org>
This image is perfectly capable of building QEMU, and indeed we do
that on gitlab. Drop the DOCKER_PARTIAL_IMAGES setting so we can also
test the gitlab build locally.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-15-alex.bennee@linaro.org>
When flex is not available, binutils sources default to the
'missing' script, but the current script available is not in
the format expected by the 'configure' script:
$ ./configure
...
/usr/src/binutils/missing: Unknown `--run' option
Try `/usr/src/binutils/missing --help' for more information
configure: WARNING: `missing' script is too old or missing
...
checking for bison... bison -y
checking for flex... no
checking for lex... no
checking for flex... /usr/src/binutils/missing flex
$ make
...
updating ldgram.h
gcc -DHAVE_CONFIG_H -I. -I. -I. -D_GNU_SOURCE -I. -I. -I../bfd -I./../bfd -I./../include -I./../intl -I../intl -w -DLOCALEDIR="\"/usr/local/share/locale\"" -W -Wall -Wstrict-prototypes -Wmissing-prototypes -w -c `test -f 'ldgram.c' || echo './'`ldgram.c
`test -f ldlex.l || echo './'`ldlex.l
/bin/sh: 1: ldlex.l: not found
make[3]: *** [Makefile:662: ldlex.c] Error 127
make[3]: Leaving directory '/usr/src/binutils/ld'
make[2]: *** [Makefile:799: all-recursive] Error 1
By pass the 'missing' script use by directly installing 'flex'
in the container.
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230112155643.7408-1-philmd@linaro.org>
Reviewed-by: Bastian-Koppelmann <kbastian@mail.uni-paderborn.de>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-14-alex.bennee@linaro.org>
Fedora 35 is EOL.
Update to upstream lcitool, that dropped f35 and added f37.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230110132700.833690-7-marcandre.lureau@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-11-alex.bennee@linaro.org>
The up-coming upgrade to Fedora 37 will bring in libtcmalloc as a
dependency of libglusterfs which confuses our fuzz run. Rather than
disable the build lets use LSAN's suppression mechanism to prevent the
job from failing.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Cc: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230124180127.1881110-10-alex.bennee@linaro.org>
It looks like this is no longer wanted, we only build the html output.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230110132700.833690-6-marcandre.lureau@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-9-alex.bennee@linaro.org>
On msys2, the shader-to-C script produces bad C:
./ui/shader/texture-blit-vert.h:2:5: error: missing terminating " character [-Werror]
Fix it by changing the line ending from crlf to lf, and convert the
script to Python (qemu build seems perl-free after that).
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230110132700.833690-2-marcandre.lureau@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-6-alex.bennee@linaro.org>
We don't need to play timing games to ensure one socat wins over the
other, just create the fifo they both can use before spawning the
processes. However in the process we need to disable two tests for
Windows platforms as we don't have an abstraction for mkfifo().
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1403
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230124180127.1881110-5-alex.bennee@linaro.org>
I think this was because older Ubuntu's didn't alias clang to whatever
the latest version was. They do now so lets use that and not break.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-4-alex.bennee@linaro.org>
Suggested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230124180127.1881110-3-alex.bennee@linaro.org>
We were using quite and old runner on our machines and running into
issues with stalling jobs. Gitlab in the meantime now reliably provide
the latest packaged versions of the runner under a stable URL. This
update:
- creates a per-arch subdir for builds
- switches from binary tarballs to deb packages
- re-uses the same binary for the secondary runner
- updates distro check for second to 22.04
Note this script isn't fully idempotent as we end up accumulating
runners especially during testing. However we also want to be able to
run twice with different GitLab keys (e.g. project and personal) so I
think we just have to be mindful of that during testing.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230124180127.1881110-2-alex.bennee@linaro.org>
When no monitor address is given, establish the QMP communication through
a socketpair() (API is also supported on Windows since Python 3.5)
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20230111080101.969151-4-marcandre.lureau@redhat.com
[Resolved conflicts, fixed typing error. --js]
Signed-off-by: John Snow <jsnow@redhat.com>
Teach QEMUMonitorProtocol to accept an exisiting socket.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20230111080101.969151-3-marcandre.lureau@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
Instead of listening for incoming connections with a SocketAddr, add a
new method open_with_socket() that accepts an existing socket.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20230111080101.969151-2-marcandre.lureau@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
Current 256KB is not enough for some real cases. As a possible solution
limit can be chosen to be the same as libvirt (10MB)
Signed-off-by: Maksim Davydov <davydov-max@yandex-team.ru>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20230112152805.33109-3-davydov-max@yandex-team.ru
Signed-off-by: John Snow <jsnow@redhat.com>
On macOS, private $TMPDIR's are the default. These $TMPDIR's are
generated from a user's unix UID and UUID [1], which can create a
relatively long path:
/var/folders/d7/rz20f6hd709c1ty8f6_6y_z40000gn/T/
QEMU's avocado tests create a temporary directory prefixed by
"avo_qemu_sock_", and create QMP sockets within _that_ as well.
The QMP socket is unnecessarily long, because a temporary directory
is created for every QEMUMachine object.
/avo_qemu_sock_uh3w_dgc/qemu-37331-10bacf110-monitor.sock
The path limit for unix sockets on macOS is 104: [2]
/*
* [XSI] Definitions for UNIX IPC domain.
*/
struct sockaddr_un {
unsigned char sun_len; /* sockaddr len including null */
sa_family_t sun_family; /* [XSI] AF_UNIX */
char sun_path[104]; /* [XSI] path name (gag) */
};
This results in avocado tests failing on macOS because the QMP unix
socket can't be created, because the path is too long:
ERROR| Failed to establish connection: OSError: AF_UNIX path too long
This change resolves by reducing the size of the socket directory prefix
and the suffix on the QMP and console socket names.
The result is paths like this:
pdel@pdel-mbp:/var/folders/d7/rz20f6hd709c1ty8f6_6y_z40000gn/T
$ tree qemu*
qemu_df4evjeq
qemu_jbxel3gy
qemu_ml9s_gg7
qemu_oc7h7f3u
qemu_oqb1yf97
├── 10a004050.con
└── 10a004050.qmp
[1] https://apple.stackexchange.com/questions/353832/why-is-mac-osx-temp-directory-in-weird-path
[2] /Library/Developer/CommandLineTools/SDKs/MacOSX12.3.sdk/usr/include/sys/un.h
Signed-off-by: Peter Delevoryas <peter@pjd.dev>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20230110082930.42129-2-peter@pjd.dev
Signed-off-by: John Snow <jsnow@redhat.com>
I've spent much time trying to debug hanging pipeline in gitlab. I
started from and idea that I have problem in code in my series (which
has some timeouts). Finally I found that the problem is that I've used
QEMUMachine class directly to avoid qtest, and didn't add necessary
arguments. Qemu fails and we wait for qmp accept endlessly. In gitlab
it's just stopped by timeout (one hour) with no sign of what's going
wrong.
With timeout enabled, gitlab don't wait for an hour and prints all
needed information.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-Id: <20220624195252.175249-1-vsementsov@yandex-team.ru>
[Fixed typing. --js]
Signed-off-by: John Snow <jsnow@redhat.com>
Fix some typos in 'python' directory.
Signed-off-by: Dongdong Zhang <zhangdongdong@eswincomputing.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20221130015358.6998-2-zhangdongdong@eswincomputing.com
[Fixed additional typo spotted by Max Filippov. --js]
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
After recent header file inclusion rework the build fails when the blkio
module is enabled:
../block/blkio.c: In function ‘blkio_detach_aio_context’:
../block/blkio.c:321:24: error: implicit declaration of function ‘bdrv_get_aio_context’; did you mean ‘qemu_get_aio_context’? [-Werror=implicit-function-declaration]
321 | aio_set_fd_handler(bdrv_get_aio_context(bs),
| ^~~~~~~~~~~~~~~~~~~~
| qemu_get_aio_context
../block/blkio.c:321:24: error: nested extern declaration of ‘bdrv_get_aio_context’ [-Werror=nested-externs]
../block/blkio.c:321:24: error: passing argument 1 of ‘aio_set_fd_handler’ makes pointer from integer without a cast [-Werror=int-conversion]
321 | aio_set_fd_handler(bdrv_get_aio_context(bs),
| ^~~~~~~~~~~~~~~~~~~~~~~~
| |
| int
In file included from /home/pipo/git/qemu.git/include/qemu/job.h:33,
from /home/pipo/git/qemu.git/include/block/blockjob.h:30,
from /home/pipo/git/qemu.git/include/block/block_int-global-state.h:28,
from /home/pipo/git/qemu.git/include/block/block_int.h:27,
from ../block/blkio.c:13:
/home/pipo/git/qemu.git/include/block/aio.h:476:37: note: expected ‘AioContext *’ but argument is of type ‘int’
476 | void aio_set_fd_handler(AioContext *ctx,
| ~~~~~~~~~~~~^~~
../block/blkio.c: In function ‘blkio_file_open’:
../block/blkio.c:821:34: error: passing argument 2 of ‘blkio_attach_aio_context’ makes pointer from integer without a cast [-Werror=int-conversion]
821 | blkio_attach_aio_context(bs, bdrv_get_aio_context(bs));
| ^~~~~~~~~~~~~~~~~~~~~~~~
| |
| int
Fix it by including 'block/block-io.h' which contains the required
declarations.
Fixes: e2c1c34f13
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 2bc956011404a1ab03342aefde0087b5b4762562.1674477350.git.pkrempa@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
virtio_blk_dma_restart_cb() is tricky because the BH must deal with
virtio_blk_data_plane_start()/virtio_blk_data_plane_stop() being called.
There are two issues with the code:
1. virtio_blk_realize() should use qdev_add_vm_change_state_handler()
instead of qemu_add_vm_change_state_handler(). This ensures the
ordering with virtio_init()'s vm change state handler that calls
virtio_blk_data_plane_start()/virtio_blk_data_plane_stop() is
well-defined. Then blk's AioContext is guaranteed to be up-to-date in
virtio_blk_dma_restart_cb() and it's no longer necessary to have a
special case for virtio_blk_data_plane_start().
2. Only blk_drain() waits for virtio_blk_dma_restart_cb()'s
blk_inc_in_flight() to be decremented. The bdrv_drain() family of
functions do not wait for BlockBackend's in_flight counter to reach
zero. virtio_blk_data_plane_stop() relies on blk_set_aio_context()'s
implicit drain, but that's a bdrv_drain() and not a blk_drain().
Note that virtio_blk_reset() already correctly relies on blk_drain().
If virtio_blk_data_plane_stop() switches to blk_drain() then we can
properly wait for pending virtio_blk_dma_restart_bh() calls.
Once these issues are taken care of the code becomes simpler. This
change is in preparation for multiple IOThreads in virtio-blk where we
need to clean up the multi-threading behavior.
I ran the reproducer from commit 49b44549ac ("virtio-blk: On restart,
process queued requests in the proper context") to check that there is
no regression.
Cc: Sergio Lopez <slp@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-id: 20221102182337.252202-1-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When we measure FIO read performance (cache=writethrough, bs=4k,
iodepth=64) in VMs, ~80K/s notifications (e.g., EPT_MISCONFIG) are observed
from guest to qemu.
It turns out those frequent notificatons are caused by interference from
worker threads. Worker threads queue bottom halves after completing IO
requests. Pending bottom halves may lead to either aio_compute_timeout()
zeros timeout and pass it to try_poll_mode() or run_poll_handlers() returns
no progress after noticing pending aio_notify() events. Both cause
run_poll_handlers() to call poll_set_started(false) to disable poll mode.
However, for both cases, as timeout is already zeroed, the event loop
(i.e., aio_poll()) just processes bottom halves and then starts the next
event loop iteration. So, disabling poll mode has no value but leads to
unnecessary notifications from guest.
To minimize unnecessary notifications from guest, defer disabling poll
mode to when the event loop is about to be blocked.
With this patch applied, FIO seq-read performance (bs=4k, iodepth=64,
cache=writethrough) in VMs increases from 330K/s to 413K/s IOPS.
Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Chao Gao <chao.gao@intel.com>
Message-id: 20220710120849.63086-1-chao.gao@intel.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Do not encode the pointer as a constant in the opcode stream.
This pointer is specific to the cpu that first generated the
translation, which runs into problems with both hot-pluggable
cpus and user-only threads, as cpus are removed. It's also a
potential correctness issue in the theoretical case of a
slightly-heterogenous system, because if CPU 0 generates a
TB and then CPU 1 executes it, CPU 1 will end up using CPU 0's
hash table, which might have a wrong set of registers in it.
(All our current systems are either completely homogenous,
M-profile, or have CPUs sufficiently different that they
wouldn't be sharing TBs anyway because the differences would
show up in the TB flags, so the correctness issue is only
theoretical, not practical.)
Perform the lookup in either helper_access_check_cp_reg,
or a new helper_lookup_cp_reg.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230106194451.1213153-3-richard.henderson@linaro.org
[PMM: added note in commit message about correctness issue]
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Move the ri == NULL case to the top of the function and return.
This allows the else to be removed and the code unindented.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20230106194451.1213153-2-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Qemu doesn't implement Debug Communication Channel, as well as the rest
of external debug interface. However, Microsoft Hyper-V in tries to
access some of those registers during an EL2 context switch.
Since there is no architectural way to not advertise support for external
debug, provide RAZ/WI stubs for OSDTRRX_EL1, OSDTRTX_EL1 and OSECCR_EL1
registers in the same way the rest of DCM is currently done. Do account
for access traps though with access_tda.
Signed-off-by: Evgeny Iakovlev <eiakovlev@linux.microsoft.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20230120155929.32384-3-eiakovlev@linux.microsoft.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The architecture does not define any functionality for the CLAIM tag bits.
So we will just keep the raw bits, as per spec.
Signed-off-by: Evgeny Iakovlev <eiakovlev@linux.microsoft.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230120155929.32384-2-eiakovlev@linux.microsoft.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
In v7m_exception_taken(), for v8M we set the EXC_RETURN.ES bit if
either the exception targets Secure or if the CPU doesn't implement
the Security Extension. This is incorrect: the v8M Arm ARM specifies
that the ES bit should be RES0 if the Security Extension is not
implemented, and the pseudocode agrees.
Remove the incorrect condition, so that we leave the ES bit 0
if the Security Extension isn't implemented.
This doesn't have any guest-visible effects for our current set of
emulated CPUs, because all our v8M CPUs implement the Security
Extension; but it's worth fixing in case we add a v8M CPU without
the extension in future.
Reported-by: Igor Kotrasinski <i.kotrasinsk@samsung.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>