Handle CPU interrupts by inline checking of a flag

Fix the nasty TCG race conditions and crashes by implementing cpu_exit
as setting a flag which is checked at the start of each TB. This is
slightly slower than the attempt to have cpu_exit alter the graph of
TBs, but it doesn't crash if a thread or signal handler calls cpu_exit
while the execution thread is itself modifying the TB graph.

This version of the patch includes command line option "-no-stopflag"
which reverts to the previous racy behaviour. This is intended for
convenience in testing and comparative benchmarking and won't be
in the final patch.

It's probably worth experimenting with whether the flag-testing
code has the branch in a sense which confuses branch-prediction
and thus whether flipping it might change performance.

Mostly this needs benchmarking to determine what the actual speed
hit is, which I never got round to. Feel free to do some :-)

[AF: CPUState -> CPUArchState]
XXX dont dump core on sigabort
XXX work around SA_RESTART race with boehm-gc (ARM only)

[AF: CPUState -> CPUArchState, adapt to reindentation]
qemu-0.9.0.cvs-binfmt

Fixes binfmt_misc setup script:
- x86_64 is i386-compatible
- m68k signature fixed
- path to QEMU

Signed-off-by: Ulrich Hecht <uli@suse.de>
qemu-cvs-alsa_bitfield

Implements TYPE_INTBITFIELD partially. (required for ALSA support)

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Ulrich Hecht <uli@suse.de>
qemu-cvs-alsa_ioctl

Implements ALSA ioctls on PPC hosts.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Ulrich Hecht <uli@suse.de>
qemu-cvs-alsa_mmap

Hack to prevent ALSA from using mmap() interface to simplify emulation.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Ulrich Hecht <uli@suse.de>
qemu-cvs-gettimeofday

No clue what this is for.
qemu-cvs-ioctl_debug

Extends unsupported ioctl debug output.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Ulrich Hecht <uli@suse.de>
qemu-cvs-ioctl_nodirection

the direction given in the ioctl should be correct so we can assume the
communication is uni-directional. The alsa developers did not like this
concept though and declared ioctls IOC_R and IOC_W even though they were
IOC_RW.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Ulrich Hecht <uli@suse.de>
qemu-img-vmdk-scsi

Support creation of SCSI VMDK images in qemu-img.

Signed-off-by: Ulrich Hecht <uli@suse.de>
configure: Enable mipsn32*-linux-user builds

Signed-off-by: Ulrich Hecht <uli@suse.de>
[AF: Merged default-configs upstream]
linux-user: add binfmt wrapper for argv[0] handling

When using qemu's linux-user binaries through binfmt, argv[0] gets lost
along the execution because qemu only gets passed in the full file name
to the executable while argv[0] can be something completely different.

This breaks in some subtile situations, such as the grep and make test
suites.

This patch adds a wrapper binary called qemu-$TARGET-binfmt that can be
used with binfmt's P flag which passes the full path _and_ argv[0] to
the binfmt handler.

The binary would be smart enough to be versatile and only exist in the
system once, creating the qemu binary path names from its own argv[0].
However, this seemed like it didn't fit the make system too well, so
we're currently creating a new binary for each target archictecture.

CC: Reinhard Max <max@suse.de>
Signed-off-by: Alexander Graf <agraf@suse.de>
linux-user: Ignore timer_create syscall

We don't implement the timer_create syscall, but shouting out loud
about it breaks some %check tests in OBS, so better ignore it silently.

Signed-off-by: Alexander Graf <agraf@suse.de>
linux-user: be silent about capget failures

Complaining about capget doesn't buy us anything, but makes %check
fail in certain builds. So better not complain about its missing
implementation and go on with life :)

Signed-off-by: Alexander Graf <agraf@suse.de>
PPC: KVM: Disable mmu notifier check

When using hugetlbfs (which is required for HV mode KVM on 970), we
check for MMU notifiers that on 970 can not be implemented properly.

So disable the check for mmu notifiers on PowerPC guests, making
KVM guests work there, even if possibly racy in some odd circumstances.
linux-user: fix segfault deadlock

When entering the guest we take a lock to ensure that nobody else messes
with our TB chaining while we're doing it. If we get a segfault inside that
code, we manage to work on, but will not unlock the lock.

This patch forces unlocking of that lock in the segv handler. I'm not sure
this is the right approach though. Maybe we should rather make sure we don't
segfault in the code? I would greatly appreciate someone more intelligible
than me to look at this :).

Example code to trigger this is at: http://csgraf.de/tmp/conftest.c

Reported-by: Fabio Erculiani <lxnay@sabayon.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
linux-user: binfmt: support host binaries

When we have a working host binary equivalent for the guest binary we're
trying to run, let's just use that instead as it will be a lot faster.

Signed-off-by: Alexander Graf <agraf@suse.de>
linux-user: ARM: Ignore immediate value for svc in thumb mode

When running in thumb mode, Linux doesn't evaluate the immediate value
of the svc instruction, but instead just always assumes the syscall number
to be in r7.

This fixes executing go_bootstrap while building go for me.

Signed-off-by: Alexander Graf <agraf@suse.de>
linux-user: arm: no tb_flush on reset

When running automoc4 as linux-user guest program, it segfaults right after
it creates a thread. Bisecting pointed to commit a84fac1426 which introduces
tb_flush on reset.

So something in our thread creation is broken. But for now, let's revert the
change to at least get a working build again.