The function notdirty_mem_write() has a sequence of actions
it has to do before and after the actual business of writing
data to host RAM to ensure that dirty flags are correctly
updated and we flush any TCG translations for the region.
We need to do this also in other places that write directly
to host RAM, most notably the TCG atomic helper functions.
Pull out the before and after pieces into their own functions.

We use an API where the prepare function stashes the various
bits of information about the write into a struct for the
complete function to use, because in the calls for the atomic
helpers the place where the complete function will be called
doesn't have the information to hand.

Cc: qemu-stable@nongnu.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1511201308-23580-2-git-send-email-peter.maydell@linaro.org

qemu-ga patch queue for 2.11

* fix potential overflow in network interface stats reporting

# gpg: Signature made Mon 20 Nov 2017 20:56:05 GMT
# gpg:                using RSA key 0x3353C9CEF108B584
# gpg: Good signature from "Michael Roth <flukshun@gmail.com>"
# gpg:                 aka "Michael Roth <mdroth@utexas.edu>"
# gpg:                 aka "Michael Roth <mdroth@linux.vnet.ibm.com>"
# Primary key fingerprint: CEAC C9E1 5534 EBAB B82D  3FA0 3353 C9CE F108 B584

* remotes/mdroth/tags/qga-pull-2017-11-20-tag:
  qga: replace GetIfEntry with GetIfEntry2 for interface stats
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

late linux-user fixes for Qemu 2.11

# gpg: Signature made Mon 20 Nov 2017 21:19:00 GMT
# gpg:                using RSA key 0xB44890DEDE3C9BC0
# gpg: Good signature from "Riku Voipio <riku.voipio@iki.fi>"
# gpg:                 aka "Riku Voipio <riku.voipio@linaro.org>"
# Primary key fingerprint: FF82 03C8 C391 98AE 0581  41EF B448 90DE DE3C 9BC0

* remotes/riku/tags/pull-linux-user-20171120:
  linux-user: Fix calculation of auxv length
  linux-user: Handle rt_sigaction correctly for SPARC
  linux-user/sparc: Put address for data faults where linux-user expects it
  linux-user/ppc: Report correct fault address for data faults
  linux-user/s390x: Mask si_addr for SIGSEGV
  linux-user: return EINVAL from prctl(PR_*_SECCOMP)
  linux-user: fix 'finshed' typo in comment
  linux-user/syscall.c: Handle SH4's exceptional alignment for p{read, write}64
  linux-user: Handle TARGET_MAP_STACK and TARGET_MAP_HUGETLB
  linux-user/hppa: Fix TARGET_F_RDLCK, TARGET_F_WRLCK, TARGET_F_UNLCK
  linux-user/hppa: Fix TARGET_MAP_TYPE
  linux-user/hppa: Fix typo for TARGET_NR_epoll_wait
  linux-user/hppa: Fix cpu_clone_regs
  linux-user/hppa: Fix TARGET_SA_* defines
  linux-user: Restrict usage of sa_restorer
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

target-arm queue:
 * hw/arm: Silence xlnx-ep108 deprecation warning during tests
 * hw/arm/aspeed: Unlock SCU when running kernel
 * arm: check regime, not current state, for ATS write PAR format
 * nvic: Fix ARMv7M MPU_RBAR reads
 * target/arm: Report GICv3 sysregs present in ID registers if needed

# gpg: Signature made Mon 20 Nov 2017 17:35:25 GMT
# gpg:                using RSA key 0x3C2525ED14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* remotes/pmaydell/tags/pull-target-arm-20171120:
  hw/arm: Silence xlnx-ep108 deprecation warning during tests
  hw/arm/aspeed: Unlock SCU when running kernel
  arm: check regime, not current state, for ATS write PAR format
  nvic: Fix ARMv7M MPU_RBAR reads
  target/arm: Report GICv3 sysregs present in ID registers if needed
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The data obtained by GetIfEntry is 32 bits, and it may overflow. Thus
using GetIfEntry2 instead of GetIfEntry.
Signed-off-by: NZhiPeng Lu <lu.zhipeng@zte.com.cn>
*avoid CamelCase variable names
*update field names for MIB_IFROW -> MIB_IF_ROW2
*dynamically probe for GetIfIndex2 to deal with older OSs
*check return value from get_interface_index
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

Fix storing cpu status (both kvm and tcg), locking around diag 308
(tcg only) and a non-zero variable in the s390-ccw bios.

# gpg: Signature made Mon 20 Nov 2017 15:18:05 GMT
# gpg:                using RSA key 0xDECF6B93C6F02FAF
# gpg: Good signature from "Cornelia Huck <conny@cornelia-huck.de>"
# gpg:                 aka "Cornelia Huck <huckc@linux.vnet.ibm.com>"
# gpg:                 aka "Cornelia Huck <cornelia.huck@de.ibm.com>"
# gpg:                 aka "Cornelia Huck <cohuck@kernel.org>"
# gpg:                 aka "Cornelia Huck <cohuck@redhat.com>"
# Primary key fingerprint: C3D0 D66D C362 4FF6 A8C0  18CE DECF 6B93 C6F0 2FAF

* remotes/cohuck/tags/s390x-20171120-v1:
  pc-bios/s390-ccw.img: update image
  pc-bios/s390-ccw: Fix problem with invalid virtio-scsi LUN when rebooting
  s390x/tcg: fix DIAG 308 with > 1 VCPU (MTTCG)
  s390x: fix storing CPU status (again)
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

ppc patch queue 2017-11-20

Here's the current queue of ppc patches.  These 2 patches are both
more complex than I'd ideally like this late in the 2.11 cycle.
However, they do fix important bugs, so I think it's worth it on
balance.

# gpg: Signature made Mon 20 Nov 2017 03:27:19 GMT
# gpg:                using RSA key 0x6C38CACA20D9B392
# gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>"
# gpg:                 aka "David Gibson (Red Hat) <dgibson@redhat.com>"
# gpg:                 aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>"
# gpg:                 aka "David Gibson (kernel.org) <dwg@kernel.org>"
# Primary key fingerprint: 75F4 6586 AE61 A66C C44E  87DC 6C38 CACA 20D9 B392

* remotes/dgibson/tags/ppc-for-2.11-20171120:
  spapr: reset DRCs after devices
  target/ppc: Update setting of cpu features to account for compat modes
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Contains the following commit:
- pc-bios/s390-ccw: Fix problem with invalid virtio-scsi LUN when rebooting
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

# gpg: Signature made Mon 20 Nov 2017 03:28:54 GMT
# gpg:                using RSA key 0xEF04965B398D6211
# gpg: Good signature from "Jason Wang (Jason Wang on RedHat) <jasowang@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: 215D 46F4 8246 689E C77F  3562 EF04 965B 398D 6211

* remotes/jasowang/tags/net-pull-request:
  hw/net/vmxnet3: Fix code to work on big endian hosts, too
  net: Transmit zero UDP checksum as 0xFFFF
  MAINTAINERS: Add missing entry for eepro100 emulation
  hw/net/eepro100: Fix endianness problem on big endian hosts
  Revert "Add new PCI ID for i82559a"
  colo-compare: fix the dangerous assignment
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

In commit 7c4ee5bc we changed the order in which we construct
the AUXV, but forgot to adjust the calculation of the length. The
result is that we set info->auxv_len to a bogus and negative value,
and then later on the code in open_self_auxv() gets confused and
ends up presenting the guest with an empty file.

Since we now have to calculate the auxv length up-front as part
of figuring out how much we're going to put on the stack, set
info->auxv_len then; this allows us to assert that we put the
same number of entries into auxv as we pre-calculated, rather
than merely having a comment saying we need to do that.

Fixes: https://bugs.launchpad.net/qemu/+bug/1728116Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

The new deprecation warning for the xlnx-ep108 machine also pops up
during "make check" which is kind of confusing. Silence it if testing
mode is enabled.
Signed-off-by: NThomas Huth <thuth@redhat.com>
Reviewed-by: NAlistair Francis <alistair.francis@xilinx.com>
Acked-by: NWei Huang <wei@redhat.com>
Message-id: 1510846183-756-1-git-send-email-thuth@redhat.com
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The ASPEED hardware contains a lock register for the SCU that disables
any writes to the SCU when it is locked. The machine comes up with the
lock enabled, but on all known hardware u-boot will unlock it and leave
it unlocked when loading the kernel.

This means the kernel expects the SCU to be unlocked. When booting from
an emulated ROM the normal u-boot unlock path is executed. Things don't
go well when booting using the -kernel command line, as u-boot does not
run first.

Change behaviour so that when a kernel is passed to the machine, set the
reset value of the SCU to be unlocked.
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Reviewed-by: NCédric Le Goater <clg@kaod.org>
Message-id: 20171114122018.12204-1-joel@jms.id.au
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

In do_ats_write(), rather than using extended_addresses_enabled() to
decide whether the value we get back from get_phys_addr() is a 64-bit
format PAR or a 32-bit one, use arm_s1_regime_using_lpae_format().

This is not really the correct answer, because the PAR format
depends on the AT instruction being used, not just on the
translation regime. However getting this correct requires a
significant refactoring, so that get_phys_addr() returns raw
information about the fault which the caller can then assemble
into a suitable FSR/PAR/syndrome for its purposes, rather than
get_phys_addr() returning a pre-formatted FSR.

However this change at least improves the situation by making
the PAR work correctly for address translation operations done
at AArch64 EL2 on the EL2 translation regime. In particular,
this is necessary for Xen to be able to run in our emulation,
so this seems like a safer interim fix given that we are in freeze.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NEdgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Tested-by: NStefano Stabellini <sstabellini@kernel.org>
Message-id: 1509719814-6191-1-git-send-email-peter.maydell@linaro.org

Fix an incorrect mask expression in the handling of v7M MPU_RBAR
reads that meant that we would always report the ADDR field as zero.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Message-id: 1509732813-22957-1-git-send-email-peter.maydell@linaro.org

The CPU ID registers ID_AA64PFR0_EL1, ID_PFR1_EL1 and ID_PFR1
have a field for reporting presence of GICv3 system registers.
We need to report this field correctly in order for Xen to
work as a guest inside QEMU emulation. We mustn't incorrectly
claim the sysregs exist when they don't, though, or Linux will
crash.

Unfortunately the way we've designed the GICv3 emulation in QEMU
puts the system registers as part of the GICv3 device, which
may be created after the CPU proper has been realized. This
means that we don't know at the point when we define the ID
registers what the correct value is. Handle this by switching
them to calling a function at runtime to read the value, where
we can fill in the GIC field appropriately.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Tested-by: NStefano Stabellini <sstabellini@kernel.org>
Message-id: 1510066898-3725-1-git-send-email-peter.maydell@linaro.org

This reverts commit e01cecab,
which breaks booting of aarch64 Linux images.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

When rebooting a guest that has a virtio-scsi disk, the s390-ccw
bios sometimes bails out with an error message like this:

! SCSI cannot report LUNs: STATUS=02 RSPN=70 KEY=05 CODE=25 QLFR=00, sure !

Enabling the scsi_req* tracing in QEMU shows that the ccw bios is
trying to execute the REPORT LUNS SCSI command with a LUN != 0, and
this causes the SCSI command to fail.
Looks like we neither clear the BSS of the s390-ccw bios during reboot,
nor do we explicitly set the default_scsi_device.lun value to 0, so
this variable can contain random values from the OS after the reboot.
By setting this variable explicitly to 0, the problem is fixed and
the reboots always succeed.

Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=1514352Signed-off-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1510942228-22822-1-git-send-email-thuth@redhat.com>
Acked-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

Currently, multi threaded TCG with > 1 VCPU gets stuck during IPL, when
the bios tries to switch to the loaded kernel via DIAG 308.

As run_on_cpu() is used, we run into a deadlock after handling the reset.
We need the iolock (just like KVM).
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20171116170526.12643-4-david@redhat.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

Looks like the last fix + cleanup introduced another bug. (for now Linux
guests don't seem to care) - we store the crs into ars.

Fixes: 947a38bd ("s390x/kvm: fix and cleanup storing CPU status")
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20171116170526.12643-2-david@redhat.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

Since commit ab06ec43 we test the vmxnet3 device in the
pxe-tester, too (when running "make check SPEED=slow"). This now
revealed that the code is not working there if the host is a big
endian machine (for example ppc64 or s390x) - "make check SPEED=slow"
is now failing on such hosts.

The vmxnet3 code lacks endianness conversions in a couple of places.
Interestingly, the bitfields in the structs in vmxnet3.h already tried to
take care of the *bit* endianness of the C compilers - but the code missed
to change the *byte* endianness when reading or writing the corresponding
structs. So the bitfields are now wrapped into unions which allow to change
the byte endianness during runtime with the non-bitfield member of the union.
With these changes, "make check SPEED=slow" now properly works on big endian
hosts, too.
Reported-by: NDavid Gibson <dgibson@redhat.com>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NDavid Gibson <dgibson@redhat.com>
Signed-off-by: NThomas Huth <thuth@redhat.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>

The checksum algorithm used by IPv4, TCP and UDP allows a zero value
to be represented by either 0x0000 and 0xFFFF. But per RFC 768, a zero
UDP checksum must be transmitted as 0xFFFF because 0x0000 is a special
value meaning no checksum.

Substitute 0xFFFF whenever a checksum is computed as zero when
modifying a UDP datagram header. Doing this on IPv4 and TCP checksums
is unnecessary but legal. Add a wrapper for net_checksum_finish() that
makes the substitution.

(We can't just change net_checksum_finish(), as that function is also
used by receivers to verify checksums, and in that case the expected
value is always 0x0000.)
Signed-off-by: NEd Swierk <eswierk@skyportsystems.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>

Signed-off-by: NStefan Weil <sw@weilnetz.de>
Signed-off-by: NJason Wang <jasowang@redhat.com>

Since commit 1865e288 ("Fix eepro100 simple transmission
mode"), the test/pxe-test is broken for the eepro100 device on big
endian hosts. However, it seems like that commit did not introduce the
problem, but just uncovered it: The EEPRO100State->tx.tbd_array_addr and
EEPRO100State->tx.tcb_bytes fields are already in host byte order, since
they have already been byte-swapped in the read_cb() function.
Thus byte-swapping them in tx_command() again results in the wrong
endianness. Removing the byte-swapping here fixes the pxe-test.
Signed-off-by: NThomas Huth <thuth@redhat.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>

This reverts commit 5e89dc01 since:

- we should use ID in the spec instead the one used by OEM
- in the future, we should allow changing id through either property
  or EEPROM file.

Cc: Stefan Weil <sw@weilnetz.de>
Cc: Michael Nawrocki <michael.nawrocki@gtri.gatech.edu>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: NStefan Weil <sw@weilnetz.de>
Signed-off-by: NJason Wang <jasowang@redhat.com>

Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Zhang Chen <zhangckid@gmail.com>
Cc: Li Zhijian <lizhijian@cn.fujitsu.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Fixes: 8ec14402Reported-by: NPeter Maydell <peter.maydell@linaro.org>
Reported-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NMao Zhongyi <maozy.fnst@cn.fujitsu.com>
Reviewed-by: NDarren Kenny <darren.kenny@oracle.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>

A DRC with a pending unplug request releases its associated device at
machine reset time.

In the case of LMB, when all DRCs for a DIMM device have been reset,
the DIMM gets unplugged, causing guest memory to disappear. This may
be very confusing for anything still using this memory.

This is exactly what happens with vhost backends, and QEMU aborts
with:

qemu-system-ppc64: used ring relocated for ring 2
qemu-system-ppc64: qemu/hw/virtio/vhost.c:649: vhost_commit: Assertion
 `r >= 0' failed.

The issue is that each DRC registers a QEMU reset handler, and we
don't control the order in which these handlers are called (ie,
a LMB DRC will unplug a DIMM before the virtio device using the
memory on this DIMM could stop its vhost backend).

To avoid such situations, let's reset DRCs after all devices
have been reset.
Reported-by: NMallesh N. Koti <mallesh@linux.vnet.ibm.com>
Signed-off-by: NGreg Kurz <groug@kaod.org>
Reviewed-by: NDaniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Reviewed-by: NMichael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

The device tree nodes ibm,arch-vec-5-platform-support and ibm,pa-features
are used to communicate features of the cpu to the guest operating
system. The properties of each of these are determined based on the
selected cpu model and the availability of hypervisor features.
Currently the compatibility mode of the cpu is not taken into account.

The ibm,arch-vec-5-platform-support node is used to communicate the
level of support for various ISAv3 processor features to the guest
before CAS to inform the guests' request. The available mmu mode should
only be hash unless the cpu is a POWER9 which is not in a prePOWER9
compat mode, in which case the available modes depend on the
accelerator and the hypervisor capabilities.

The ibm,pa-featues node is used to communicate the level of cpu support
for various features to the guest os. This should only contain features
relevant to the operating mode of the processor, that is the selected
cpu model taking into account any compat mode. This means that the
compat mode should be taken into account when choosing the properties of
ibm,pa-features and they should match the compat mode selected, or the
cpu model selected if no compat mode.

Update the setting of these cpu features in the device tree as described
above to properly take into account any compat mode. We use the
ppc_check_compat function which takes into account the current processor
model and the cpu compat mode.
Signed-off-by: NSuraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

Block layer patches for 2.11.0-rc2

# gpg: Signature made Fri 17 Nov 2017 17:58:36 GMT
# gpg:                using RSA key 0x7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74  56FE 7F09 B272 C88F 2FD6

* remotes/kevin/tags/for-upstream: (25 commits)
  iotests: Make 087 pass without AIO enabled
  block: Make bdrv_next() keep strong references
  qcow2: Fix overly broad madvise()
  qcow2: Refuse to get unaligned offsets from cache
  qcow2: Add bounds check to get_refblock_offset()
  block: Guard against NULL bs->drv
  qcow2: Unaligned zero cluster in handle_alloc()
  qcow2: check_errors are fatal
  qcow2: reject unaligned offsets in write compressed
  iotests: Add test for failing qemu-img commit
  tests: Add check-qobject for equality tests
  iotests: Add test for non-string option reopening
  block: qobject_is_equal() in bdrv_reopen_prepare()
  qapi: Add qobject_is_equal()
  qapi/qlist: Add qlist_append_null() macro
  qapi/qnull: Add own header
  qcow2: fix image corruption on commit with persistent bitmap
  iotests: test clearing unknown autoclear_features by qcow2
  block: Fix permissions in image activation
  qcow2: fix image corruption after committing qcow2 image into base
  ...
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Block patches for 2.11.0-rc2

# gpg: Signature made Fri Nov 17 18:22:07 2017 CET
# gpg:                using RSA key F407DB0061D5CF40
# gpg: Good signature from "Max Reitz <mreitz@redhat.com>"
# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1  1829 F407 DB00 61D5 CF40

* mreitz/tags/pull-block-2017-11-17:
  iotests: Make 087 pass without AIO enabled
  block: Make bdrv_next() keep strong references
  qcow2: Fix overly broad madvise()
  qcow2: Refuse to get unaligned offsets from cache
  qcow2: Add bounds check to get_refblock_offset()
  block: Guard against NULL bs->drv
  qcow2: Unaligned zero cluster in handle_alloc()
  qcow2: check_errors are fatal
  qcow2: reject unaligned offsets in write compressed
  iotests: Add test for failing qemu-img commit
  tests: Add check-qobject for equality tests
  iotests: Add test for non-string option reopening
  block: qobject_is_equal() in bdrv_reopen_prepare()
  qapi: Add qobject_is_equal()
  qapi/qlist: Add qlist_append_null() macro
  qapi/qnull: Add own header
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

If AIO has not been enabled in the qemu build that is to be tested, we
should skip the "aio=native without O_DIRECT" test instead of failing.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20171115180732.31753-1-mreitz@redhat.com
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

On one hand, it is a good idea for bdrv_next() to return a strong
reference because ideally nearly every pointer should be refcounted.
This fixes intermittent failure of iotest 194.

On the other, it is absolutely necessary for bdrv_next() itself to keep
a strong reference to both the BB (in its first phase) and the BDS (at
least in the second phase) because when called the next time, it will
dereference those objects to get a link to the next one.  Therefore, it
needs these objects to stay around until then.  Just storing the pointer
to the next in the iterator is not really viable because that pointer
might become invalid as well.

Both arguments taken together means we should probably just invoke
bdrv_ref() and blk_ref() in bdrv_next().  This means we have to assert
that bdrv_next() is always called from the main loop, but that was
probably necessary already before this patch and judging from the
callers, it also looks to actually be the case.

Keeping these strong references means however that callers need to give
them up if they decide to abort the iteration early.  They can do so
through the new bdrv_next_cleanup() function.
Suggested-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20171110172545.32609-1-mreitz@redhat.com
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

@mem_size and @offset are both size_t, thus subtracting them from one
another will just return a big size_t if mem_size < offset -- even more
obvious here because the result is stored in another size_t.

Checking that result to be positive is therefore not sufficient to
exclude the case that offset > mem_size.  Thus, we currently sometimes
issue an madvise() over a very large address range.

This is triggered by iotest 163, but with -m64, this does not result in
tangible problems.  But with -m32, this test produces three segfaults,
all of which are fixed by this patch.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20171114184127.24238-1-mreitz@redhat.com
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Reviewed-by: NDarren Kenny <darren.kenny@oracle.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Instead of using an assertion, it is better to emit a corruption event
here.  Checking all offsets for correct alignment can be tedious and it
is easily possible to forget to do so.  qcow2_cache_do_get() is a
function every L2 and refblock access has to go through, so this is a
good central point to add such a check.

And for good measure, let us also add an assertion that the offset is
non-zero.  Making this a corruption event is not feasible, because a
zero offset usually means something special (such as the cluster is
unused), so all callers should be checking this anyway.  If they do not,
it is their fault, hence the assertion here.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20171110203111.7666-6-mreitz@redhat.com
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Reported-by: NR. Nageswara Sastry <nasastry@in.ibm.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1728661Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20171110203111.7666-5-mreitz@redhat.com
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

We currently do not guard everywhere against a NULL bs->drv where we
should be doing so.  Most of the places fixed here just do not care
about that case at all.

Some care implicitly, e.g. through a prior function call to
bdrv_getlength() which would always fail for an ejected BDS.  Add an
assert there to make it more obvious.

Other places seem to care, but do so insufficiently: Freeing clusters in
a qcow2 image is an error-free operation, but it may leave the image in
an unusable state anyway.  Giving qcow2_free_clusters() an error code is
not really viable, it is much easier to note that bs->drv may be NULL
even after a successful driver call.  This concerns bdrv_co_flush(), and
the way the check is added to bdrv_co_pdiscard() (in every iteration
instead of only once).

Finally, some places employ at least an assert(bs->drv); somewhere, that
may be reasonable (such as in the reopen code), but in
bdrv_has_zero_init(), it is definitely not.  Returning 0 there in case
of an ejected BDS saves us much headache instead.
Reported-by: NR. Nageswara Sastry <nasastry@in.ibm.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1728660Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20171110203111.7666-4-mreitz@redhat.com
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

We should check whether the cluster offset we are about to use is
actually valid; that is, whether it is aligned to cluster boundaries.
Reported-by: NR. Nageswara Sastry <nasastry@in.ibm.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1728643
Buglink: https://bugs.launchpad.net/qemu/+bug/1728657Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20171110203111.7666-3-mreitz@redhat.com
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

When trying to repair a dirty image, qcow2_check() may apparently
succeed (no really fatal error occurred that would prevent the check
from continuing), but if check_errors in the result object is non-zero,
we cannot trust the image to be usable.
Reported-by: NR. Nageswara Sastry <nasastry@in.ibm.com>
Buglink: https://bugs.launchpad.net/qemu/+bug/1728639Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20171110203111.7666-2-mreitz@redhat.com
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Misaligned compressed write is not supported.
Signed-off-by: NAnton Nefedov <anton.nefedov@virtuozzo.com>
Message-id: 1510654613-47868-2-git-send-email-anton.nefedov@virtuozzo.com
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20170616135847.17726-1-mreitz@redhat.com
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Add a new test file (check-qobject.c) for unit tests that concern
QObjects as a whole.

Its only purpose for now is to test the qobject_is_equal() function.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20171114180128.17076-7-mreitz@redhat.com
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>