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
The QERR_ macros are leftovers from the days of "rich" error objects.
They're used with error_set() and qerror_report(), and expand into the
first *two* arguments. This trickiness has become pointless. Clean
up the balloon ones.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
... and simplify a bit. Permits factoring out common error checks in
the next commit.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
The QERR_ macros are leftovers from the days of "rich" error objects.
They're used with error_set() and qerror_report(), and expand into the
first *two* arguments. This trickiness has become pointless. Clean
this one up.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
QMP command query-spice exists only #ifdef CONFIG_SPICE. Due to QAPI
limitations, we need a dummy function anyway, but it's unreachable.
Our current dummy function goes out of its way to produce the exact
same error as the QMP core does for unknown commands. Cute, but both
unclean and unnecessary. Replace by straight abort().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
It's dead code when CONFIG_SPICE is off. If it wasn't, it would crash
dereferencing the null pointer returned by the qmp_query_spice()
dummy in qmp.c.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Commit 7572150 adopted QERR_DEVICE_NOT_ACTIVE for the purpose,
probably because adding another error seemed cumbersome overkill.
Produces "No spice device has been activated", which is awkward.
We've since abandoned our quest for "rich" error objects. Time to
undo the damage to this error message. Replace it by "SPICE is not in
use".
Keep the stupid DeviceNotActive ErrorClass for compatibility, even
though Libvirt doesn't use it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Into qemu_using_spice(). For want of a better place, put it next the
existing monitor command handler dummies in qemu-spice.h.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
When passing ancillary data through a unix socket, handle
credentials properly instead of doing a simple copy and
issuing a warning.
Signed-off-by: Alex Suykov <alex.suykov@gmail.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The m68k signal frame setup code which writes the signal return
trampoline code to the stack was assuming that a 'long' was 32 bits;
on 64 bit systems this meant we would end up writing the 32 bit
(2 insn) trampoline sequence to retaddr+4,retaddr+6 instead of
the intended retaddr+0,retaddr+2, resulting in a guest crash when
it tried to execute the invalid zero-bytes at retaddr+0.
Fix by using uint32_t instead; also use uint16_t rather than short
for consistency. This fixes bug LP:1404690.
Reported-by: Michel Boaventura
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Without this fix, qemu segfaults when emulating the sigaltstack syscall,
because it incorrectly treats the ss_flags field as 64 bits rather than 32
bits.
Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
linux-user passes the cmd argument of the ioctl syscall as a signed long,
but compares it to an unsigned int when iterating through the ioctl_entries
list. When the cmd is a large value like 0x80047476 (TARGET_TIOCSWINSZ on
mips64) it gets sign-extended to 0xffffffff80047476, causing the comparison
to fail and resulting in lots of spurious "Unsupported ioctl" errors.
Changing the target_cmd field in the ioctl_entries list to a signed int
causes those values to be sign-extended as well during the comparison.
Signed-off-by: Ed Swierk <eswierk@skyportsystems.com>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The resource argument is translated from host to target for
[gs]etprlimit but not for prlimit64. Fix this.
Signed-off-by: Felix Janda <felix.janda@posteo.de>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The function copy_siginfo_to_user() just calls tswap_siginfo(), so
call the latter function directly and delete the wrapper function.
The wrapper is actually misleading since it implies that the
semantics are like the kernel function with the same name which
copies the data to a guest user-space address. In fact tswap_siginfo()
just does data-structure conversion between two structures whose
addresses are host addresses (the copy to userspace is handled
in QEMU by the lock_user/unlock_user calls).
This also fixes clang complaints about the wrapper being unused
in some configs.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The function end_exclusive() isn't used on all targets; mark it as
such to avoid a clang warning.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The start_exclusive() infrastructure is used on all target
architectures, even if only to do the "stop all CPUs before
dumping core" in force_sig(), so be consistent and call
cpu_exec_start/end in the main loop of every target.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
The aCC array in fpopcode.c is completely unused in QEMU; delete
it (silencing a clang warning).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
For historical reasons, the define for the shmat() syscall on Alpha is
NR_osf_shmat; however it has the same semantics as this syscall does
on all other architectures, so define TARGET_NR_shmat as well so that
QEMU's code for the syscall is enabled.
This patch brings our behaviour on the LTP shmat tests into line
with that for ARM (still not a perfect pass rate but not "this syscall
is completely broken" as we had before).
(Problem detected via a clang warning that the do_shmat() function
was unused on Alpha.)
Cc: Richard Henderson <rth@twiddle.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Remove the function current_exec_domain_sig(), which always returns
its argument. This was intended as a stub for supporting the kernel's
exec_domain handling, but:
* we don't have any of the other code for execution domains
* in the kernel this handling is architecture-specific, not generic
* we only call this function in the x86, ppc and sh4 signal code paths,
and the PPC one is wrong anyway because the PPC kernel doesn't
have this signal-remapping code
So it's best to simply delete the function; any future attempt to
implement exec domains will be better served by adding the correct
code from scratch based on the kernel sources at that time.
This change also fixes some clang warnings about the function being
defined but not used for some target architectures.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
A bunch of fixes all over the place. Also, beginning to generalize acpi build
code for reuse by ARM.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging
pci, pc, virtio fixes and cleanups
A bunch of fixes all over the place. Also, beginning to generalize acpi build
code for reuse by ARM.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
# gpg: Signature made Tue 27 Jan 2015 13:12:25 GMT using RSA key ID D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>"
* remotes/mst/tags/for_upstream:
pc-dimm: Add Error argument to pc_existing_dimms_capacity
pc-dimm: Make pc_existing_dimms_capacity global
pc: Fix DIMMs capacity calculation
smbios: Don't report unknown CPU speed (fix SVVP regression)
smbios: Fix dimm size calculation when RAM is multiple of 16GB
bios-linker-loader: move source to common location
bios-linker-loader: move header to common location
virtio: fix feature bit checks
bios-tables-test: split piix4 and q35 tests
acpi: build_append_nameseg(): add padding if necessary
acpi: update generated hex files
acpi-test: update expected DSDT
pc: acpi: fix WindowsXP BSOD when memory hotplug is enabled
pci: Split pcie_host_mmcfg_map()
Add some trace calls to pci.c.
ich9: add disable_s3, disable_s4, s4_val properties
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Now that pc_existing_dimms_capacity() is an API, include Error pointer
as an argument and modify the caller appropriately.
Suggested-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Move pc_existing_dimms_capacity() to pc-dimm.c since it would be needed
by PowerPC memory hotplug code too.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
pc_existing_dimms_capacity() is returning DIMMs count rather than capacity.
Fix this to return the capacity. Also consider only realized devices for
capacity calculation.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
SVVP requires processor speed on Type 4 structures to not be unknown.
This was fixed in SeaBIOS 0.5.0 (in 2009), but the bug was reintroduced
in QEMU 2.1.
Revert to old behavior and report CPU speed as 2000 MHz instead of
unknown.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
The Memory Device size calculation logic is broken when the RAM size is
a multiple of 16GB, making the size of the last entry be 0 instead of
16GB. Fix the logic to handle that case correctly.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
There are plans to use bios linker by MIPS, ARM.
It's only used by ACPI ATM, so put it in hw/acpi
and make it depend on CONFIG_ACPI.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Several places check against the feature bit number instead of against
the feature bit. Fix them.
Cc: qemu-stable@nongnu.org
Reported-by: Thomas Huth <thuth@linux.vnet.ibm.com>
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>
This makes it clear which one is failing.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
According to ACPI spec NameSeg shorter than 4 characters
must be padded up to 4 characters with "_" symbol.
ACPI 5.0: 20.2.2 "Name Objects Encoding"
Do it in build_append_nameseg() so that caller shouldn't know
or care about it.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Claudio Fontana <claudio.fontana@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Previous patch
pc: acpi: fix WindowsXP BSOD when memory hotplug is enabled
changed DSDT, update hex files for non-iasl builds.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Previous patch
pc: acpi: fix WindowsXP BSOD when memory hotplug is enabled
changed DSDT, update expected test files.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/bkoppelmann/tags/pull-tricore-20150127' into staging
tricore bugfixes and RR1, RR2, RRPW and RRR insn
# gpg: Signature made Tue 27 Jan 2015 12:02:06 GMT using RSA key ID 6B69CA14
# gpg: Good signature from "Bastian Koppelmann <kbastian@mail.uni-paderborn.de>"
* remotes/bkoppelmann/tags/pull-tricore-20150127:
target-tricore: Add instructions of RRR opcode format
target-tricore: Add instructions of RRPW opcode format
target-tricore: Add instructions of RR2 opcode format
target-tricore: Add instructions of RR1 opcode format, that have 0x93 as first opcode
target-tricore: split up suov32 into suov32_pos and suov32_neg
target-tricore: Fix bugs found by coverity
target-tricore: calculate av bits before saturation
target-tricore: Several translator and cpu model fixes
target-tricore: Add missing ULL suffix on 64 bit constant
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Add microcode generator function gen_cond_sub.
Add helper functions:
* ixmax/ixmin: search for the max/min value and its related index in a
vector of 16-bit values.
* pack: dack two data registers into an IEEE-754 single precision floating
point format number.
* dvadj: divide-adjust the result after dvstep instructions.
* dvstep: divide a reg by a divisor, producing 8-bits of quotient at a time.
OPCM_32_RRR_FLOAT -> OPCM_32_RRR_DIVIDE
Signed-off-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
Reviewed-by: Richard Henderson <rth@twiddle.net>
suov checks unsigned for an overflow and an underflow, after some arithmetic
operations and saturates the result to either max_uint32 or 0. So far we
handled this by expanding to the next bigger data type and compare whether
the result is > max_uint32 or < 0.
However this approach can fail for an 32 bit multiplication, if both operands of
the multiplication are 0x80000000. This sets the sign bit of the 64 bit integer
and would result in a false saturation to 0.
Since unsigned operations, e.g add, sub, mul always result in either a positive
or negative overflow, we split the functions for suov32 up into two functions
(suov32_pos, suov32_neg) for each case.
Signed-off-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>