Request merging must not result in a huge request that exceeds the
maximum number of iovec elements. Use BlockLimits.max_iov instead of
hardcoding IOV_MAX.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
1. avoid possible superflous checking
2. make code more robustness
["make code more robustness" refers to avoiding integer
underflows/overflows.
--Stefan]
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Message-id: 1447207166-12612-1-git-send-email-arei.gonglei@huawei.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
src is stored in shared memory and src->nr_segments is dereferenced
twice at the end of the function. If a compiler decides to compile this
into two separate memory accesses then the size limitation could be
bypassed.
Fix it by removing the double access to src->nr_segments.
This is part of XSA-155.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
The Xen toolstack uses "vhd" to specify a disk in VHD format, however
the name of the driver in QEMU is "vpc". Replace "vhd" with "vpc", so
that QEMU can find the right driver to use for it.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
The official way of enabling dataplane is through the "iothread"
property that references an iothread object created by "-object
iothread". Since the old "x-data-plane=on" way now even crashes, it's
probably easier to just drop it:
$ qemu-system-x86_64 -drive file=null-co://,id=d0,if=none \
-device virtio-blk-pci,drive=d0,x-data-plane=on
ERROR:/home/fam/work/qemu/qom/object.c:1515:
object_get_canonical_path_component: assertion failed: (obj->parent != NULL)
Aborted
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1449485967-19240-1-git-send-email-famz@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
For the "main area on file, oob in memory" case, fix the shifts so that
we erase the correct number of pages.
Signed-off-by: Ricard Wanderlöf <ricardw@axis.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This code has been dead for three years (since commit 7e7b7cba1).
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
"werror=report" would free the req in virtio_blk_handle_rw_error, we
mustn't write to it in that case.
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1448239280-15025-1-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The shifts of the address mask and value shift beyond 32 bits when there
are 5 address cycles.
Cc: qemu-stable@nongnu.org
Signed-off-by: Rabin Vincent <rabin.vincent@axis.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When a request R is absorbed by request M, it is appended to the
"mr_next" queue led by M, and is completed together with the completion
of M, in virtio_blk_rw_complete.
During DMA restart in virtio_blk_dma_restart_bh, requests in s->rq are
parsed and submitted again, possibly with a stale req->mr_next. It could
be a problem if the request merging in virtio_blk_handle_request hasn't
refreshed every mr_next pointer, in which case, virtio_blk_rw_complete
could walk through unexpected requests following the stale pointers.
Fix this by unsetting the pointer in virtio_blk_rw_complete. It is safe
because this req is either completed and freed right away, or it will be
restarted and parsed from scratch out of the vq later.
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Currently both BLKIF_OP_WRITE and BLKIF_OP_FLUSH_DISKCACHE are being
accounted as write operations.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 7a2a14e3ac62027aa6267a6c02abc70717be9c0a.1446044837.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When creating snapshot with the dataplane enabled, the snapshot file gets
not the actual state of virtqueue, because the current state is stored in
VirtIOBlockDataPlane. Therefore, before saving snapshot need to sync
the dataplane vring state to the virtqueue. The dataplane will resume its
work at the next notify virtqueue.
When snapshot loads with loadvm we get a message:
VQ 0 size 0x80 Guest index 0x15f5 inconsistent with Host index 0x0:
delta 0x15f5
error while loading state for instance 0x0 of device
'0000:00:08.0/virtio-blk'
Error -1 while loading VM state
to reproduce the error I used the following hmp commands:
savevm snap1
loadvm snap1
qemu parameters:
--enable-kvm -smp 4 -m 1024 -drive file=/var/lib/libvirt/images/centos6.4.qcow2,if=none,id=drive-virtio-disk0,format=qcow2,cache=none,aio=native -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x8,drive=drive-virtio-disk0,id=virtio-disk0 -set device.virtio-disk0.x-data-plane=on
Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Message-id: 1445859777-2982-1-git-send-email-den@openvz.org
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: "Michael S. Tsirkin" <mst@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Devices that are compliant with virtio-1 do not support scsi
passthrough any more (and it has not been a recommended setup
anyway for quite some time). To avoid having to switch it off
explicitly in newer qemus that turn on virtio-1 by default, let's
switch the default to scsi=false for 2.5.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1444991154-79217-4-git-send-email-cornelia.huck@de.ibm.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
They will be excluded by type in the nested event loops in block layer,
so that unwanted events won't be processed there.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
All callers pass in false, and the real external ones will switch to
true in coming patches.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
blk_bs() will not necessarily return a non-NULL value any more (unless
blk_is_available() is true or it can be assumed to otherwise, e.g.
because it is called immediately after a successful blk_new_with_bs() or
blk_new_open()).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The tray of an FDD is open iff there is no medium inserted (there are
only two states for an FDD: "medium inserted" or "no medium inserted").
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Simplify memory allocation by sticking with a single API. GSlice
is not that fast anyway (tcmalloc/jemalloc are better).
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The raw-posix block driver implements Linux AIO batching so multiple
requests can be submitted with a single io_submit(2) system call.
Batching is currently only used by virtio-scsi and
virtio-blk-data-plane.
Enable batching for regular virtio-blk so the number of io_submit(2)
system calls is reduced for workloads with queue depth > 1.
In 4KB random read performance tests with queue depth 32, the CPU
utilization on the host is reduced by 9.4%. The fio job is as follows:
[global]
bs=4k
ioengine=libaio
iodepth=32
direct=1
sync=0
time_based=1
runtime=30
clocksource=gettimeofday
ramp_time=5
[job1]
rw=randread
filename=/dev/vdb
size=4096M
write_bw_log=fio
write_iops_log=fio
write_lat_log=fio
log_avg_msec=1000
This benchmark was run on an raw image on LVM. The disk was an SSD
drive and -drive cache=none,aio=native was used.
Tested-by: Pradeep Surisetty <psuriset@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Symptom:
$ qemu-system-x86_64 -m 10000000
Unexpected error in ram_block_add() at /work/armbru/qemu/exec.c:1456:
upstream-qemu: cannot set up guest memory 'pc.ram': Cannot allocate memory
Aborted (core dumped)
Root cause: commit ef701d7 screwed up handling of out-of-memory
conditions. Before the commit, we report the error and exit(1), in
one place, ram_block_add(). The commit lifts the error handling up
the call chain some, to three places. Fine. Except it uses
&error_abort in these places, changing the behavior from exit(1) to
abort(), and thus undoing the work of commit 3922825 "exec: Don't
abort when we can't allocate guest memory".
The three places are:
* memory_region_init_ram()
Commit 4994653 (right after commit ef701d7) lifted the error
handling further, through memory_region_init_ram(), multiplying the
incorrect use of &error_abort. Later on, imitation of existing
(bad) code may have created more.
* memory_region_init_ram_ptr()
The &error_abort is still there.
* memory_region_init_rom_device()
Doesn't need fixing, because commit 33e0eb5 (soon after commit
ef701d7) lifted the error handling further, and in the process
changed it from &error_abort to passing it up the call chain.
Correct, because the callers are realize() methods.
Fix the error handling after memory_region_init_ram() with a
Coccinelle semantic patch:
@r@
expression mr, owner, name, size, err;
position p;
@@
memory_region_init_ram(mr, owner, name, size,
(
- &error_abort
+ &error_fatal
|
err@p
)
);
@script:python@
p << r.p;
@@
print "%s:%s:%s" % (p[0].file, p[0].line, p[0].column)
When the last argument is &error_abort, it gets replaced by
&error_fatal. This is the fix.
If the last argument is anything else, its position is reported. This
lets us check the fix is complete. Four positions get reported:
* ram_backend_memory_alloc()
Error is passed up the call chain, ultimately through
user_creatable_complete(). As far as I can tell, it's callers all
handle the error sanely.
* fsl_imx25_realize(), fsl_imx31_realize(), dp8393x_realize()
DeviceClass.realize() methods, errors handled sanely further up the
call chain.
We're good. Test case again behaves:
$ qemu-system-x86_64 -m 10000000
qemu-system-x86_64: cannot set up guest memory 'pc.ram': Cannot allocate memory
[Exit 1 ]
The next commits will repair the rest of commit ef701d7's damage.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1441983105-26376-3-git-send-email-armbru@redhat.com>
Reviewed-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
* qemu_mutex_lock_iothread "No such process" fix
* cutils: qemu_strto* wrappers
* iohandler.c simplification
* Many other fixes and misc patches.
And some MTTCG work (with Emilio's fixes squashed):
* Signal-free TCG kick
* Removing spinlock in favor of QemuMutex
* User-mode emulation multi-threading fixes/docs
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging
* Support for jemalloc
* qemu_mutex_lock_iothread "No such process" fix
* cutils: qemu_strto* wrappers
* iohandler.c simplification
* Many other fixes and misc patches.
And some MTTCG work (with Emilio's fixes squashed):
* Signal-free TCG kick
* Removing spinlock in favor of QemuMutex
* User-mode emulation multi-threading fixes/docs
# gpg: Signature made Thu 10 Sep 2015 09:03:07 BST using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg: aka "Paolo Bonzini <pbonzini@redhat.com>"
* remotes/bonzini/tags/for-upstream: (44 commits)
cutils: work around platform differences in strto{l,ul,ll,ull}
cpu-exec: fix lock hierarchy for user-mode emulation
exec: make mmap_lock/mmap_unlock globally available
tcg: comment on which functions have to be called with mmap_lock held
tcg: add memory barriers in page_find_alloc accesses
remove unused spinlock.
replace spinlock by QemuMutex.
cpus: remove tcg_halt_cond and tcg_cpu_thread globals
cpus: protect work list with work_mutex
scripts/dump-guest-memory.py: fix after RAMBlock change
configure: Add support for jemalloc
add macro file for coccinelle
configure: factor out adding disas configure
vhost-scsi: fix wrong vhost-scsi firmware path
checkpatch: remove tests that are not relevant outside the kernel
checkpatch: adapt some tests to QEMU
CODING_STYLE: update mixed declaration rules
qmp: Add example usage of strto*l() qemu wrapper
cutils: Add qemu_strtoull() wrapper
cutils: Add qemu_strtoll() wrapper
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
A number of files were including signal.h but not using any
of the functions it provides
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Commit ef546f1275 ("virtio: add
feature checking helpers") introduced a helper __virtio_has_feature.
We don't want to use reserved identifiers, though, so let's
rename __virtio_has_feature to virtio_has_feature and virtio_has_feature
to virtio_vdev_has_feature.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The i8257 DMA controller uses an idle bottom half, which by default
does not cause the main loop to exit. Therefore, the DMA_schedule
function is there to ensure that the CPU relinquishes the iothread
mutex to the iothread.
However, this is not enough since the iothread will call
aio_compute_timeout() and go to sleep again. In the iothread
world, forcing execution of the idle bottom half is much simpler,
and only requires a call to qemu_notify_event(). Do it, removing
the need for the "cpu_request_exit" pseudo-irq. The next patch
will remove it.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use pow2ceil() to round up to the next power of 2, rather
than an inline calculation.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1437741192-20955-4-git-send-email-peter.maydell@linaro.org
Chapter 6.3 of spec said
"
Transitional devices MUST offer, and if offered by the device
transitional drivers MUST accept the following:
VIRTIO_F_ANY_LAYOUT (27)
"
So this patch only clear VIRTIO_F_LAYOUT for legacy device.
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-block@nongnu.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
SCSI passthrough was no longer supported in virtio 1.0, so this patch
fail the get_features() when both 1.0 and scsi is set. And also only
advertise VIRTIO_BLK_F_SCSI for legacy virtio-blk device.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Implement support in Identify and Get/Set Features to properly report
and allow to change the Volatile Write Cache status reported by the
virtual NVMe device.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Implement a real flush instead of faking it. This is especially important
as Qemu assume Write back cashing by default and thus requires a working
cache flush operation for data integrity.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
in_num = req->elem.in_num, and req->elem.in_num is
checked in line 489, so the check about in_num variable
is superflous, let's drop it.
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1435138164-11728-1-git-send-email-arei.gonglei@huawei.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Each call of the virtio_blk_reset() function calls blk_drain_all(),
which works for all existing BlockDriverStates, while draining only
one is needed.
This patch replaces blk_drain_all() by blk_drain() in
virtio_blk_reset(). virtio_blk_data_plane_stop() should be called
after draining because it restores vblk->complete_request.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com>
Message-id: 1434537440-28236-3-git-send-email-yarygin@linux.vnet.ibm.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
We create optional sections with this patch. But we already have
optional subsections. Instead of having two mechanism that do the
same, we can just generalize it.
For subsections we just change:
- Add a needed function to VMStateDescription
- Remove VMStateSubsection (after removal of the needed function
it is just a VMStateDescription)
- Adjust the whole tree, moving the needed function to the corresponding
VMStateDescription
Signed-off-by: Juan Quintela <quintela@redhat.com>
* CONFIG_PARALLEL fix from Mirek
* Atomic/optimized dirty bitmap access from myself and Stefan
* BUILD_DIR convenience/bugfix from Peter C
* Memory leak fix from Shannon
* SMM improvements (though still TCG only) from myself and Gerd, acked by mst
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging
* KVM error improvement from Laurent
* CONFIG_PARALLEL fix from Mirek
* Atomic/optimized dirty bitmap access from myself and Stefan
* BUILD_DIR convenience/bugfix from Peter C
* Memory leak fix from Shannon
* SMM improvements (though still TCG only) from myself and Gerd, acked by mst
# gpg: Signature made Fri Jun 5 18:45:20 2015 BST using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg: aka "Paolo Bonzini <pbonzini@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg: It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1
# Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83
* remotes/bonzini/tags/for-upstream: (62 commits)
update Linux headers from kvm/next
atomics: add explicit compiler fence in __atomic memory barriers
ich9: implement SMI_LOCK
q35: implement TSEG
q35: add test for SMRAM.D_LCK
q35: implement SMRAM.D_LCK
q35: add config space wmask for SMRAM and ESMRAMC
q35: fix ESMRAMC default
q35: implement high SMRAM
hw/i386: remove smram_update
target-i386: use memory API to implement SMRAM
hw/i386: add a separate region that tracks the SMRAME bit
target-i386: create a separate AddressSpace for each CPU
vl: run "late" notifiers immediately
qom: add object_property_add_const_link
vl: allow full-blown QemuOpts syntax for -global
pflash_cfi01: add secure property
pflash_cfi01: change to new-style MMIO accessors
pflash_cfi01: change big-endian property to BIT type
target-i386: wake up processors that receive an SMI
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When this property is set, MMIO accesses are only allowed with the
MEMTXATTRS_SECURE attribute. This is used for secure access to UEFI
variables stored in flash.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The RQM bit in MSR should be set whenever the guest is supposed to
access the FIFO, and it should be cleared in all other cases. This is
important so the guest can't continue writing/reading the FIFO beyond
the length that it's suppossed to access (see CVE-2015-3456).
Commit e9077462 fixed the CVE by adding code that avoids the buffer
overflow; however it doesn't correct the wrong behaviour of the floppy
controller which should already have cleared RQM.
Currently, RQM stays set all the time and during all phases while a
command is being processed. This is error-prone because the command has
to explicitly clear the flag if it doesn't need data (and indeed, the
two buggy commands that are the culprits for the CVE just forgot to do
that).
This patch clears RQM immediately as soon as all bytes that are expected
have been received. If the the FIFO is used in the next phase, the flag
has to be set explicitly there.
It also clear RQM after receiving all bytes even if the phase transition
immediately sets it again. While it's technically not necessary at the
moment because the state between clearing and setting RQM is not
observable by the guest, this is more explicit and matches how real
hardware works. It will actually become necessary in qemu once
asynchronous code paths are introduced.
This alone should have been enough to fix the CVE, but now we have two
lines of defense - even better.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 1432214378-31891-8-git-send-email-kwolf@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
This commit makes similar improvements as have already been made to the
write function: Instead of relying on a flag in the MSR to distinguish
controller phases, use the explicit phase that we store now. Assertions
of the right MSR flags are added.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 1432214378-31891-7-git-send-email-kwolf@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
