The separate handling of DIRTY_MEMORY_MIGRATION, which does not
call log_start/log_stop callbacks when it changes in a region's
dirty logging mask, has caused several bugs.
One recent example is commit 4cc856f (kvm-all: Sync dirty-bitmap from
kvm before kvm destroy the corresponding dirty_bitmap, 2015-04-02).
Another performance problem is that KVM keeps tracking dirty pages
after a failed live migration, which causes bad performance due to
disallowing huge page mapping.
This patch removes the root cause of the problem by reporting
DIRTY_MEMORY_MIGRATION changes via log_start and log_stop.
Note that we now have to rebuild the FlatView when global dirty
logging is enabled or disabled; this ensures that log_start and
log_stop callbacks are invoked.
This will also be used to make the setting of bitmaps conditional.
In general, this patch lets users of the memory API ignore the
global state of dirty logging if they handle dirty logging
generically per region.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It is okay if memory is not mapped into the guest but has dirty logging
enabled. When this happens, KVM will not do anything and only accesses
from the host will be logged.
This can be triggered by iofuzz.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
DIRTY_MEMORY_CODE is only needed for TCG. By adding it directly to
mr->dirty_log_mask, we avoid testing for TCG everywhere a region is
checked for the enabled/disabled state of dirty logging.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
dpy_gfx_update_dirty expects DIRTY_MEMORY_VGA logging to be always on,
but that will not be the case soon. Because it computes the memory
region on the fly for every update (with memory_region_find), it cannot
enable/disable logging by itself.
We could always treat updates as invalidations if dirty logging is
not enabled, assuming that the board will enable logging on the
RAM region that includes the framebuffer.
However, the function is unused, so just drop it.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
framebuffer.c expects DIRTY_MEMORY_VGA logging to be always on, but that
will not be the case soon. Because framebuffer.c computes the memory
region on the fly for every update (with memory_region_find), it cannot
enable/disable logging by itself.
Instead, always treat updates as invalidations if dirty logging is
not enabled, assuming that the board will enable logging on the
RAM region that includes the framebuffer.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When the dirty log mask will also cover other bits than DIRTY_MEMORY_VGA,
some listeners may be interested in the overall zero/non-zero value of
the dirty log mask; others may be interested in the value of single bits.
For this reason, always call log_start/log_stop if bits have respectively
appeared or disappeared, and pass the old and new values of the dirty log
mask so that listeners can distinguish the kinds of change.
For example, KVM checks if dirty logging used to be completely disabled
(in log_start) or is now completely disabled (in log_stop). On the
other hand, Xen has to check manually if DIRTY_MEMORY_VGA changed,
since that is the only bit it cares about.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
For now memory regions only track DIRTY_MEMORY_VGA individually, but
this will change soon. To support this, split memory_region_is_logging
in two functions: one that returns a given bit from dirty_log_mask,
and one that returns the entire mask. memory_region_is_logging gets an
extra parameter so that the compiler flags misuse.
While VGA-specific users (including the Xen listener!) will want to keep
checking that bit, KVM and vhost check for "any bit except migration"
(because migration is handled via the global start/stop listener
callbacks).
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
These are strictly speaking only needed for KVM and Xen, but it's still
nice to be consistent.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This will be required soon by the memory core.
Tested-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Coalescing work on MMIO, not RAM, thus this call has no effect.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
DIRTY_MEMORY_MIGRATION is triggered by memory_global_dirty_log_start
and memory_global_dirty_log_stop, so it cannot be used with
memory_region_set_log.
Specify this in the documentation and assert it.
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
make can be invoked in the individual build dirs to build an individual
target or just a single file of a target. e.g.
touch translate-all.c
make -C microblazeel-softmmu translate-all.o
There is however a small bug when using the pixman submodule.
config-host.mak will ref BUILD_DIR for the pixman -I CFLAGS:
grep BUILD_DIR config-host.mak
QEMU_CFLAGS=-I$(SRC_PATH)/pixman/pixman -I$(BUILD_DIR)/pixman/pixman ...
This causes a build failure as -I/pixman/pixman (BUILD_DIR=="") will
not be found.
BUILD_DIR is usually set by the top level Makefile. Just lazy-set it in
Makefile.target to the parent directory.
Granted, this will not work if the pixman submodule is not prebuilt,
but it at least means you can do incremental partial builds once you
have done your initial full build (or attempt) from the top level.
The next step would be refactor make infrastructure to rebuild pixman
on a submake like the one above.
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Message-Id: <1432618686-16077-1-git-send-email-crosthwaite.peter@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
phys_page_set_level is writing zeroes to a struct that has just been
filled in by phys_map_node_alloc. Instead, tell phys_map_node_alloc
whether to fill in the page "as a leaf" or "as a non-leaf".
memcpy is faster than struct assignment, which copies each bitfield
individually. A compiler bug (https://gcc.gnu.org/PR66391), and
small memcpys like this one are special-cased anyway, and optimized
to a register move, so just use the memcpy.
This cuts the cost of phys_page_set_level from 25% to 5% when
booting qboot.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Achieved by:
- Remembering the server fd with a global variable, in order to access
it from nbd_client_closed.
- Checking nbd_can_accept() and updating server_fd handler whenever
client connects or disconnects.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1432032670-15124-3-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
On POWER8 systems, KVM checks if VCPU is running on primary threads,
and that secondary threads are offline. If this is not the case,
ioctl() fails with errno set to EBUSY.
QEMU aborts with a non explicit error message:
$ ./qemu-system-ppc64 --nographic -machine pseries,accel=kvm
error: kvm run failed Device or resource busy
To help user to diagnose the problem, this patch adds an informative
error message.
There is no easy way to check if SMT is enabled before starting the VCPU,
and as this case is the only one setting errno to EBUSY, we just check
the errno value to display a message.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <1431976007-20503-1-git-send-email-lvivier@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Disabling CONFIG_PARALLEL cause removing parallel_hds_isa_init defined in
parallel.c. This function is called during initialization of some boards so
disabling CONFIG_PARALLEL cause build failure.
This patch moves parallel_hds_isa_init to hw/isa/isa-bus.c so it is included
in case of disabled CONFIG_PARALLEL. Build is successful but qemu will abort
with "Unknown device" error when function is called.
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
Message-Id: <1431509970-32154-1-git-send-email-mrezanin@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This time there are a lot of s390x TCG emulation bug fixes - almost all
of them from Aurelien, who returned from nirvana :).
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Merge remote-tracking branch 'remotes/agraf/tags/signed-s390-for-upstream' into staging
Patch queue for s390 - 2015-06-05
This time there are a lot of s390x TCG emulation bug fixes - almost all
of them from Aurelien, who returned from nirvana :).
# gpg: Signature made Fri Jun 5 00:39:27 2015 BST using RSA key ID 03FEDC60
# gpg: Good signature from "Alexander Graf <agraf@suse.de>"
# gpg: aka "Alexander Graf <alex@csgraf.de>"
* remotes/agraf/tags/signed-s390-for-upstream: (34 commits)
target-s390x: Only access allocated storage keys
target-s390x: fix MVC instruction when areas overlap
target-s390x: use softmmu functions for mvcp/mvcs
target-s390x: support non current ASC in s390_cpu_handle_mmu_fault
target-s390x: add a cpu_mmu_idx_to_asc function
target-s390x: implement high-word facility
target-s390x: implement load-and-trap facility
target-s390x: implement miscellaneous-instruction-extensions facility
target-s390x: implement LPDFR and LNDFR instructions
target-s390x: implement TRANSLATE EXTENDED instruction
target-s390x: implement TRANSLATE AND TEST instruction
target-s390x: implement LOAD FP INTEGER instructions
target-s390x: move SET DFP ROUNDING MODE to the correct facility
target-s390x: move STORE CLOCK FAST to the correct facility
target-s390x: change CHRL and CGHRL format to RIL-b
target-s390x: fix CLGIT instruction
target-s390x: fix exception for invalid operation code
target-s390x: implement LAY and LAEY instructions
target-s390x: move a few instructions to the correct facility
target-s390x: detect tininess before rounding for FP operations
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Since the block alignment code is now effectively independent of the DMA
implementation, this variable is no longer required and can be removed.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 1433455177-21243-5-git-send-email-mark.cave-ayland@ilande.co.uk
Signed-off-by: John Snow <jsnow@redhat.com>
With the offset/len functions taking care of all of the alignment mapping
in isolation from the DMA tranasaction, many comments are now unnecessary.
Remove these and tidy up a few constants at the same time.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 1433455177-21243-4-git-send-email-mark.cave-ayland@ilande.co.uk
Signed-off-by: John Snow <jsnow@redhat.com>
In particular, this fixes a bug whereby chains of overlapping head/tail chains
would incorrectly write over each other's remainder cache. This is the access
pattern used by OS X/Darwin and fixes an issue with a corrupt Darwin
installation in my local tests.
While we are here, rename the DBDMA_io struct property remainder to
head_remainder for clarification.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 1433455177-21243-3-git-send-email-mark.cave-ayland@ilande.co.uk
Signed-off-by: John Snow <jsnow@redhat.com>
For better handling of unaligned block device accesses.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 1433455177-21243-2-git-send-email-mark.cave-ayland@ilande.co.uk
Signed-off-by: John Snow <jsnow@redhat.com>
We allocate ram_size / PAGE_SIZE storage keys, so we need to make sure that
we only access that many. Unfortunately the code can overrun this array by
one, potentially overwriting unrelated memory.
Fix it by limiting storage keys to their scope.
Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
The MVC instruction and the memmove C funtion do not have the same
semantic when memory areas overlap:
MVC: When the operands overlap, the result is obtained as if the
operands were processed one byte at a time and each result byte were
stored immediately after fetching the necessary operand byte.
memmove: Copying takes place as though the bytes in src are first copied
into a temporary array that does not overlap src or dest, and the bytes
are then copied from the temporary array to dest.
The behaviour is therefore the same when the destination is at a lower
address than the source, but not in the other case. This is actually a
trick for propagating a value to an area. While the current code detects
that and call memset in that case, it only does for 1-byte value. This
trick can and is used for propagating two or more bytes to an area.
In the softmmu case, the call to mvc_fast_memmove is correct as the
above tests verify that source and destination are each within a page,
and both in a different page. The part doing the move 8 bytes by 8 bytes
is wrong and we need to check that if the source and destination
overlap, they do with a distance of minimum 8 bytes before copying 8
bytes at a time.
In the user code, we should check check that the destination is at a
lower address than source or than the end of the source is at a lower
address than the destination before calling memmove. In the opposite
case we fallback to the same code as the softmmu one. Note that l
represents (length - 1).
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
mvcp and mvcs helper get access to the physical memory by a call to
mmu_translate for the virtual to real conversion and then using ldb_phys
and stb_phys to physically access the data. In practice this is quite
slow because it bypasses the QEMU softmmu TLB and because stb_phys calls
try to invalidate the corresponding memory for each access.
Instead use cpu_ldb_{primary,secondary} for the loads and
cpu_stb_{primary,secondary} for the stores. Ideally this should be
further optimized by a call to memcpy, but that already improves the
boot time of a guest by a factor 1.8.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
s390_cpu_handle_mmu_fault currently looks at the current ASC mode
defined in PSW mask instead of the MMU index. This prevent emulating
easily instructions using a specific ASC mode. Fix that by using the
MMU index converted back to ASC using the just added cpu_mmu_idx_to_asc
function.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
Use constants to define the MMU indexes, and add a function to do
the reverse conversion of cpu_mmu_index.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
Besides RISBHG and RISBLG, all high-word instructions are not
implemented. Fix that.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
At the same time move the trap code from op_ct into gen_trap and use it
for all new functions. The value needs to be stored back to register
before the exception, but also before the brcond (as we don't use
temp locals). That's why we can't use wout helper.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
RISBGN is the same as RISBG, but without setting the condition code.
CLT and CLGT are the same as CLRT and CLGRT, but using memory for the
second operand.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
This complete the floating point support sign handling facility.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
It is part of the basic zArchitecture instructions.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
It is part of the basic zArchitecture instructions. Allow it to be call
from EXECUTE.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
This is needed to pass the gcc.c-torture/execute/ieee/20010114-2.c test
in the gcc testsuite.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
It belongs to the DFP rounding facility.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
STORE CLOCK FAST should be in the SCF facility.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
Change to match the PoP. In practice both format RIL-a and RIL-b have
the same fields. They differ on the way we decode the fields, and it's
done correctly in QEMU.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
The COMPARE LOGICAL IMMEDIATE AND TRAP instruction should compare the
numbers as unsigned, as its name implies.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
When an operation code is not recognized (ie invalid instruction) an
operation exception should be generated instead of a specification
exception. The latter is for valid opcode, with invalid operands or
modifiers.
This give a very basic GDB support in the guest, as it uses the invalid
opcode 0x0001 to generate a trap.
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
This complete the general-instructions-extension facility, enable it.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
[agraf: remove facility bit]
Signed-off-by: Alexander Graf <agraf@suse.de>
LY is part of the long-displacement facility.
RISBHG and RISBLG are part of the high-word facility.
STCMH is part of the z/Architecture.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
The s390x floating point unit detects tininess before rounding, so set
the softfloat fp_status up appropriately.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
LOAD LENGTHENED and LOAD ROUNDED are considered as FP operations and
thus need to convert input sNaN into corresponding qNaN.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
The cpu_mmu_index function wrongly looks at PSW P bit to determine the
MMU index, while this bit actually only control the use of priviledge
instructions. The addressing mode is detected by looking at the PSW ASC
bits instead.
This used to work more or less correctly up to kernel 3.6 as the kernel
was running in primary space and userland in secondary space. Since
kernel 3.7 the default is to run the kernel in home space and userland
in primary space. While the current QEMU code seems to work it open some
security issues, like accessing the lowcore memory in R/W mode from a
userspace process once it has been accessed by the kernel (it is then
cached by the QEMU TLB).
At the same time change the MMU_USER_IDX value so that it matches the
value used in recent kernels.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
runtime_exception computes the psw.addr value using the actual exception
address and the instruction length computed by calling the get_ilen
function. However as explained above the get_ilen code, it returns the
actual instruction length, and not the ILC. Therefore there is no need to
multiply the value by 2.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
When consecutive memory locations are on page boundary a page fault
might occur when using the LOAD MULTIPLE instruction. In that case real
hardware doesn't load any register.
This is an important detail in case the base register is in the list
of registers to be loaded. If a page fault occurs this register might be
overwritten and when the instruction is later restarted the wrong
base register value is useD.
Fix this by first loading the first and last value from memory, hence
triggering all possible page faults, and then the remaining registers.
This fixes random segmentation faults seen in the guest.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
Save the timer target value in the SPT helper, so that the STPT helper
can compute the remaining time.
This allow the Linux kernel to correctly do time accounting.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
The STCKC instruction just returns the last written clock comparator
value and KVM already provides the corresponding variable.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
Now that clock_value is only used in one place, we can inline it in
the STCK helper.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
The clock comparator and the QEMU timer work the same way, triggering
at a given time, they just differ by the origin and the scale. It is
therefore possible to go from one to another without using the current
clock value. This spares two calls to qemu_clock_get_ns, which probably
return slightly different values, possibly reducing the accuracy.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Alexander Graf <agraf@suse.de>
