Add assertion checking when cpreg structures are registered that they
either forbid raw-access attempts or at least make an attempt at
handling them. Also add an assert in the raw-accessor-of-last-resort,
to avoid silently doing a read or write from offset zero, which is
actually AArch32 CPU register r0.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1422282372-13735-3-git-send-email-peter.maydell@linaro.org
Reviewed-by: Greg Bellows <greg.bellows@linaro.org>
We currently mark ARM coprocessor/system register definitions with
the flag ARM_CP_NO_MIGRATE for two different reasons:
1) register is an alias on to state that's also visible via
some other register, and that other register is the one
responsible for migrating the state
2) register is not actually state at all (for instance the TLB
or cache maintenance operation "registers") and it makes no
sense to attempt to migrate it or otherwise access the raw state
This works fine for identifying which registers should be ignored
when performing migration, but we also use the same functions for
synchronizing system register state between QEMU and the kernel
when using KVM. In this case we don't want to try to sync state
into registers in category 2, but we do want to sync into registers
in category 1, because the kernel might have picked a different
one of the aliases as its choice for which one to expose for
migration. (In particular, on 32 bit hosts the kernel will
expose the state in the AArch32 version of the register, but
TCG's convention is to mark the AArch64 version as the version
to migrate, even if the CPU being emulated happens to be 32 bit,
so almost all system registers will hit this issue now that we've
added AArch64 system emulation.)
Fix this by splitting the NO_MIGRATE flag in two (ALIAS and NO_RAW)
corresponding to the two different reasons we might not want to
migrate a register. When setting up the TCG list of registers to
migrate we honour both flags; when populating the list from KVM,
only ignore registers which are NO_RAW.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Greg Bellows <greg.bellows@linaro.org>
Message-id: 1422282372-13735-2-git-send-email-peter.maydell@linaro.org
[PMM: changed ARM_CP_NO_MIGRATE to ARM_CP_ALIAS on new SP_EL1 and
SP_EL2 reginfo stanzas since there was a (semantic) merge conflict
with the patchset that added those]
Update to arm_cpu_reset() to reset into the highest available exception level
based on the set ARM features.
Signed-off-by: Greg Bellows <greg.bellows@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1422029835-4696-4-git-send-email-greg.bellows@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Added RVBAR_EL2 and RVBAR_EL3 CP register support. All RVBAR_EL# registers
point to the same location and only the highest EL version exists at any one
time.
Signed-off-by: Greg Bellows <greg.bellows@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1422029835-4696-3-git-send-email-greg.bellows@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Fix the RVBAR_EL1 CP register opc2 encoding from 2 to 1
Signed-off-by: Greg Bellows <greg.bellows@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1422029835-4696-2-git-send-email-greg.bellows@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This patch allows the board to specifiy the number of NVIC interrupt
lines when using armv7m_init.
Signed-off-by: Alistair Francis <alistair23@gmail.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 5a0b0fcc778df0340899f488053acc9493679e03.1422077994.git.alistair23@gmail.com
[PMM: removed stale FIXME comment]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This patch moves the memory region init code from the
armv7m_init function to the stellaris_init function
Signed-off-by: Alistair Francis <alistair23@gmail.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 4836be7e1d708554d6eb0bc639dc2fbf7dac0458.1422077994.git.alistair23@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Jason Wang will be co-maintaining the QEMU net subsystem with me. He
has contributed improvements and reviewed patches over the past years as
part of working on virtio-net and virtualized networking.
Jason has already been backing me up with patch reviews. For the time
being I will continue to submit pull requests.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Commit d8d9581460 added explicit object_unparent() calls for
dynamically allocated MemoryRegions. The VFIOMSIXInfo structure also
contains such a MemoryRegion, covering the mmap'd region of a PCI BAR
above the MSI-X table. This structure is freed as part of the class
exit function and therefore also needs an explicit object_unparent().
Failing to do this results in random segfaults due to fields within
the structure, often the class pointer, being reclaimed and corrupted
by the time object_finalize_child_property() is called for the object.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-stable@nongnu.org # 2.2
This patch fixes the bug with borrow_in being set incorrectly, but it
also simplifies the logic to be much more plain, improving speed. It
fixes both the 32-bit SLB* and 64-bit SLBG*.
The SLBG* change has been well-tested. I haven't tested the SLB* change
explicitly, but the code was copy-pasted from the tested code.
The error of these functions' current implementations would not likely
be triggered by compiler-generated code, since the only error was in the
state of the carry/borrow flag. Compilers rarely generate an
instruction sequence such as carry-set -> carry-set-and-use ->
carry-use.
(With Paolo's fix and mine, there are still a couple of failures from
GMP's testsuite, but they are almost surely due to incorrect code
generation from gcc 4.9. But since this gcc is running under qemu, it
might be qemu bugs. I intend to investigate this.)
Signed-off-by: Torbjorn Granlund <torbjorng@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
This is needed to run the GMP testsuite.
Reported-by: Torbjorn Granlund <torbjorng@google.com>
Tested-by: Torbjorn Granlund <torbjorng@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
The variables s390_opformats and s390_num_opformats are unused and
provoke clang warnings:
disas/s390.c:849:33: warning: variable 's390_opformats' is not needed and will not be emitted [-Wunneeded-internal-declaration]
static const struct s390_opcode s390_opformats[] =
^
disas/s390.c:875:18: warning: unused variable 's390_num_opformats' [-Wunused-const-variable]
static const int s390_num_opformats =
^
Delete them, since QEMU doesn't use them.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Message-id: 1419373100-17690-3-git-send-email-peter.maydell@linaro.org
Signed-off-by: Richard Henderson <rth@twiddle.net>
The function check_privileged() is only used in the softmmu configs;
wrap it in an #ifndef CONFIG_USER_ONLY to avoid clang warnings on the
linux-user builds.
[rth: Remove inline marker too; it was only there to prevent exactly
this warning in GCC.]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Message-id: 1419373100-17690-2-git-send-email-peter.maydell@linaro.org
Signed-off-by: Richard Henderson <rth@twiddle.net>
The implementation had been incomplete, as we did not store the
machine type. Note that the machine_type member is still unset
during initialization, so this has no effect yet.
Signed-off-by: Richard Henderson <rth@twiddle.net>
in old code.
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Merge remote-tracking branch 'remotes/cohuck/tags/s390x-20150203' into staging
Some bugfixes and cleanups for s390x, both in the new pci code and
in old code.
# gpg: Signature made Tue 03 Feb 2015 13:01:04 GMT using RSA key ID C6F02FAF
# gpg: Good signature from "Cornelia Huck <huckc@linux.vnet.ibm.com>"
# gpg: aka "Cornelia Huck <cornelia.huck@de.ibm.com>"
* remotes/cohuck/tags/s390x-20150203:
pc-bios/s390-ccw: update binary
pc-bios/s390-ccw: fix sparse warnings
s390x/ipl: Improved code indentation in s390_ipl_init()
s390x/kvm: unknown DIAGNOSE code should give a specification exception
s390x/kvm: Fix diag-308 register decoding
s390x/pci: fix dma notifications in rpcit instruction
s390x/pci: check for invalid function handle
s390x/pci: avoid sign extension in stpcifc
s390: Plug memory leak on s390_pci_generate_event() error path
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Fix some sparse warnings in the s390-ccw bios.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
The indentation of the code in s390_ipl_init() can be simplified
a little bit by removing superfluous else-statements.
Suggested-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
As described in CP programming services an unimplemented DIAGNOSE
function should return a specification exception. Today we give the
guest an operation exception.
As both exception types are suppressing and Linux as a guest does not
care about the type of program check in its exception table handler
as long as both types have the same kind of error handling (nullifying,
terminating, suppressing etc.) this was unnoticed.
Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Fix the decoding of the r1 register number in the diagnose 308 handler.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
The virtual I/O address range passed to rpcit instruction might not
map to consecutive physical guest pages. For this we have to translate
and create mapping notifications for each vioa page separately.
Signed-off-by: Yi Min Zhao <zyimin@cn.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
broken guest may provide 0 (invalid) function handle to zpci
instructions. Since we use function handle 0 to indicate an empty
slot in the PHB we have to add an additional check to spot this
kind of error.
Signed-off-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
This patch avoids sign extension and fixes a data conversion
bug in stpcifc. Both issues where found by Coverity.
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
v1->v2 changes are the new qemu-thread patch to fix Mac OS X,
and cleaning up warnings.
v2->v3 removed the patch to enable modules by default.
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging
The important bits here are the first part of RCU.
v1->v2 changes are the new qemu-thread patch to fix Mac OS X,
and cleaning up warnings.
v2->v3 removed the patch to enable modules by default.
# gpg: Signature made Mon 02 Feb 2015 19:28:03 GMT 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:
scsi: Fix scsi_req_cancel_async for no aiocb req
cpu-exec: simplify init_delay_params
cpu-exec: simplify align_clocks
memory: avoid ref/unref in memory_region_find
memory: protect current_map by RCU
memory: remove assertion on memory_region_destroy
rcu: add call_rcu
rcu: allow nesting of rcu_read_lock/rcu_read_unlock
rcu: add rcutorture
rcu: add rcu library
qemu-thread: fix qemu_event without futexes
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
scsi_req_cancel_complete is responsible for releasing the request, so we
shouldn't skip it in any case. This doesn't affect the only existing
caller, virtio-scsi, but is useful for other devices once they use it.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
With the introduction of QEMU_CLOCK_VIRTUAL_RT, the computation of
sc->diff_clk can be simplified nicely:
qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
qemu_clock_get_ns(QEMU_CLOCK_REALTIME) +
cpu_get_clock_offset()
= qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
(qemu_clock_get_ns(QEMU_CLOCK_REALTIME) - cpu_get_clock_offset())
= qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
(qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timers_state.cpu_clock_offset)
= qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) -
qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL_RT)
Cc: Sebastian Tanase <sebastian.tanase@openwide.fr>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
sc->diff_clk is already equal to sleep_delay (split in a second and a
nanosecond part). If you subtract sleep_delay - rem_delay, the result
is exactly rem_delay.
Cc: Sebastian Tanase <sebastian.tanase@openwide.fr>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Do the entire lookup under RCU, which avoids atomic operations
in flatview_ref and flatview_unref.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Replace the flat_view_mutex with RCU, avoiding futex contention for
dataplane on large systems and many iothreads.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Now that memory_region_destroy can be called from an RCU callback,
checking the BQL-protected global memory_region_transaction_depth
does not make much sense.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Asynchronous callbacks provided by call_rcu are particularly important
for QEMU, because the BQL makes it hard to use synchronize_rcu.
In addition, the current RCU implementation is not particularly friendly
to multiple concurrent synchronize_rcu callers, making call_rcu even
more important.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This includes a (mangled) copy of the liburcu code. The main changes
are: 1) removing dependencies on many other header files in liburcu; 2)
removing for simplicity the tentative busy waiting in synchronize_rcu,
which has limited performance effects; 3) replacing futexes in
synchronize_rcu with QemuEvents for Win32 portability. The API is
the same as liburcu, so it should be possible in the future to require
liburcu on POSIX systems for example and use our copy only on Windows.
Among the various versions available I chose urcu-mb, which is the
least invasive implementation even though it does not have the
fastest rcu_read_{lock,unlock} implementation. The urcu flavor can
be changed later, after benchmarking.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This had a possible deadlock that was visible with rcutorture.
qemu_event_set qemu_event_wait
----------------------------------------------------------------
cmpxchg reads FREE, writes BUSY
futex_wait: pthread_mutex_lock
futex_wait: value == BUSY
xchg reads BUSY, writes SET
futex_wake: pthread_cond_broadcast
futex_wait: pthread_cond_wait
<deadlock>
The fix is simply to avoid condvar tricks and do the obvious locking
around pthread_cond_broadcast:
qemu_event_set qemu_event_wait
----------------------------------------------------------------
cmpxchg reads FREE, writes BUSY
futex_wait: pthread_mutex_lock
futex_wait: value == BUSY
xchg reads BUSY, writes SET
futex_wake: pthread_mutex_lock
(blocks)
futex_wait: pthread_cond_wait
(mutex unlocked)
futex_wake: pthread_cond_broadcast
futex_wake: pthread_mutex_unlock
futex_wait: pthread_mutex_unlock
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The code in the softfloat source files is under a mixture of
licenses: the original code and many changes from QEMU contributors
are under the base SoftFloat-2a license; changes from Stefan Weil
and RedHat employees are GPLv2-or-later; changes from Fabrice Bellard
are under the BSD license. Clarify this in the comments at the
top of each affected source file, including a statement about
the assumed licensing for future contributions, so we don't need
to remember to ask patch submitters explicitly to pick a license.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Andreas Färber <afaerber@suse.de>
Acked-by: Aurelien Jarno <aurelien@aurel32.net>
Acked-by: Avi Kivity <avi.kivity@gmail.com>
Acked-by: Ben Taylor <bentaylor.solx86@gmail.com>
Acked-by: Blue Swirl <blauwirbel@gmail.com>
Acked-by: Christophe Lyon <christophe.lyon@st.com>
Acked-by: Fabrice Bellard <fabrice@bellard.org>
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Acked-by: Juan Quintela <quintela@redhat.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Acked-by: Paul Brook <paul@codesourcery.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Richard Henderson <rth@twiddle.net>
Acked-by: Richard Sandiford <rdsandiford@googlemail.com>
Acked-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1421073508-23909-5-git-send-email-peter.maydell@linaro.org
Revert the parts of commits b645bb4885 and 5a6932d51d which are still
in the codebase and under a SoftFloat-2b license.
Reimplement support for architectures where the most significant bit
in the mantissa is 1 for a signaling NaN rather than a quiet NaN,
by adding handling for SNAN_BIT_IS_ONE being set to the functions
which test values for NaN-ness.
This includes restoring the bugfixes lost in the reversion where
some of the float*_is_quiet_nan() functions were returning true
for both signaling and quiet NaNs.
[This is a mechanical squashing together of two separate "revert"
and "reimplement" patches.]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1421073508-23909-4-git-send-email-peter.maydell@linaro.org
Revert the remaining portions of commits 75d62a5856 and 3430b0be36
which are under a SoftFloat-2b license, ie the functions
uint64_to_float32() and uint64_to_float64(). (The float64_to_uint64()
and float64_to_uint64_round_to_zero() functions were completely
rewritten in commits fb3ea83aa and 0a87a3107d so can stay.)
Reimplement from scratch the uint64_to_float64() and uint64_to_float32()
conversion functions.
[This is a mechanical squashing together of two separate "revert"
and "reimplement" patches.]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1421073508-23909-3-git-send-email-peter.maydell@linaro.org
This commit applies the changes to master which correspond to
replacing commit 158142c2c2 with a set of changes made by:
* taking the SoftFloat-2a release
* mechanically transforming the block comment style
* reapplying Fabrice's original changes from 158142c2c2
This commit was created by:
diff -u 158142c2c2 import-sf-2a
patch -p1 --fuzz 10 <../relicense-patch.txt
(where import-sf-2a is the branch resulting from the changes above).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1421073508-23909-2-git-send-email-peter.maydell@linaro.org