monitor_qmp_dispatcher_co() runs in the iohandler AioContext that is not
polled during nested event loops. The coroutine currently reschedules
itself in the main loop's qemu_aio_context AioContext, which is polled
during nested event loops. One known problem is that QMP device-add
calls drain_call_rcu(), which temporarily drops the BQL, leading to all
sorts of havoc like other vCPU threads re-entering device emulation code
while another vCPU thread is waiting in device emulation code with
aio_poll().
Paolo Bonzini suggested running non-coroutine QMP handlers in the
iohandler AioContext. This avoids trouble with nested event loops. His
original idea was to move coroutine rescheduling to
monitor_qmp_dispatch(), but I resorted to moving it to qmp_dispatch()
because we don't know if the QMP handler needs to run in coroutine
context in monitor_qmp_dispatch(). monitor_qmp_dispatch() would have
been nicer since it's associated with the monitor implementation and not
as general as qmp_dispatch(), which is also used by qemu-ga.
A number of qemu-iotests need updated .out files because the order of
QMP events vs QMP responses has changed.
Solves Issue #1933.
Cc: qemu-stable@nongnu.org
Fixes: 7bed89958b ("device_core: use drain_call_rcu in in qmp_device_add")
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2215192
Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2214985
Buglink: https://issues.redhat.com/browse/RHEL-17369
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20240118144823.1497953-4-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Tested-by: Fiona Ebner <f.ebner@proxmox.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Try writing zeroes to a FUSE export while allowing the area to be
unmapped; block/file-posix.c generally implements writing zeroes with
BDRV_REQ_MAY_UNMAP ('write -zu') by calling fallocate(PUNCH_HOLE). This
used to lead to a blk_pdiscard() in the FUSE export, which may or may
not lead to the area being zeroed. HEAD^ fixed this to use
blk_pwrite_zeroes() instead (again with BDRV_REQ_MAY_UNMAP), so verify
that running `qemu-io 'write -zu'` on a FUSE exports always results in
zeroes being written.
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20230227104725.33511-3-hreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
These tests read size information (sometimes disk size, sometimes
virtual size) from qemu-img info's output. Once qemu-img starts
printing info about child nodes, we are going to see multiple instances
of that per image, but these tests are only interested in the first one,
so use "head -n 1" to get it.
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220620162704.80987-11-hreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
With CAP_DAC_OVERRIDE (which e.g. root generally has), permission checks
will be bypassed when opening files.
308 in one instance tries to open a read-only file (FUSE export) with
qemu-io as read/write, and expects this to fail. However, when running
it as root, opening will succeed (thanks to CAP_DAC_OVERRIDE) and only
the actual write operation will fail.
Note this as "Case not run", but have the test pass in either case.
Reported-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Fixes: 2c7dd057aa
("export/fuse: Pass default_permissions for mount")
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220103120014.13061-1-hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The error message claims the parameter is invalid:
$ qemu-system-x86_64 -object qom-type=nonexistent
qemu-system-x86_64: -object qom-type=nonexistent: Invalid parameter 'nonexistent'
What's wrong is actually the *value* 'nonexistent'. Improve the
message to
qemu-system-x86_64: -object qom-type=nonexistent: Parameter 'qom-type' does not accept value 'nonexistent'
Fixes: https://gitlab.com/qemu-project/qemu/-/issues/608
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20211020180231.434071-1-armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Test that +w on read-only FUSE exports returns an EROFS error. u+x on
the other hand should work. (There is no special reason to choose u+x
here, it simply is like +w another flag that is not set by default.)
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20210625142317.271673-6-mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Without the allow_other mount option, no user (not even root) but the
one who started qemu/the storage daemon can access the export. Allow
users to configure the export such that such accesses are possible.
While allow_other is probably what users want, we cannot make it an
unconditional default, because passing it is only possible (for non-root
users) if the global fuse.conf configuration file allows it. Thus, the
default is an 'auto' mode, in which we first try with allow_other, and
then fall back to without.
FuseExport.allow_other reports whether allow_other was actually used as
a mount option or not. Currently, this information is not used, but a
future patch will let this field decide whether e.g. an export's UID and
GID can be changed through chmod.
One notable thing about 'auto' mode is that libfuse may print error
messages directly to stderr, and so may fusermount (which it executes).
Our export code cannot really filter or hide them. Therefore, if 'auto'
fails its first attempt and has to fall back, fusermount will print an
error message that mounting with allow_other failed.
This behavior necessitates a change to iotest 308, namely we need to
filter out this error message (because if the first attempt at mounting
with allow_other succeeds, there will be no such message).
Furthermore, common.rc's _make_test_img should use allow-other=off for
FUSE exports, because iotests generally do not need to access images
from other users, so allow-other=on or allow-other=auto have no
advantage. OTOH, allow-other=on will not work on systems where
user_allow_other is disabled, and with allow-other=auto, we get said
error message that we would need to filter out again. Just disabling
allow-other is simplest.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20210625142317.271673-3-mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We do not do any permission checks in fuse_open(), so let the kernel do
them. We already let fuse_getattr() report the proper UNIX permissions,
so this should work the way we want.
This causes a change in 308's reference output, because now opening a
non-writable export with O_RDWR fails already, instead of only actually
attempting to write to it. (That is an improvement.)
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20210625142317.271673-2-mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
We are going to drop group file. Define group in tests as a preparatory
step.
The patch is generated by
cd tests/qemu-iotests
grep '^[0-9]\{3\} ' group | while read line; do
file=$(awk '{print $1}' <<< "$line");
groups=$(sed -e 's/^... //' <<< "$line");
awk "NR==2{print \"# group: $groups\"}1" $file > tmp;
cat tmp > $file;
done
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210116134424.82867-7-vsementsov@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
We have good coverage of the normal I/O paths now, but what remains is a
test that tests some more special cases: Exporting an image on itself
(thus turning a formatted image into a raw one), some error cases, and
non-writable and non-growable exports.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20201027190600.192171-21-mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
