Currently maxmem limit is not checked and depends on
hotplug region container not being able to fit more RAM
than maxmem. Do check explicitly so that it would
be possible to change hotplug container size later
to deal with fragmentation.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging
Three patches to fix ExtINT for the QEMU implementation of the local APIC.
# gpg: Signature made Mon 24 Nov 2014 13:38:36 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:
apic: fix incorrect handling of ExtINT interrupts wrt processor priority
apic: fix loss of IPI due to masked ExtINT
apic: avoid getting out of halted state on masked PIC interrupts
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This fixes another failure with ExtINT, demonstrated by QNX. The failure
mode is as follows:
- IPI sent to cpu 0 (bit set in APIC irr)
- IPI accepted by cpu 0 (bit cleared in irr, set in isr)
- IPI sent to cpu 0 (bit set in both irr and isr)
- PIC interrupt sent to cpu 0
The PIC interrupt causes CPU_INTERRUPT_HARD to be set, but
apic_irq_pending observes that the highest pending APIC interrupt priority
(the IPI) is the same as the processor priority (since the IPI is still
being handled), so apic_get_interrupt returns a spurious interrupt rather
than the pending PIC interrupt. The result is an endless sequence of
spurious interrupts, since nothing will clear CPU_INTERRUPT_HARD.
Instead, ExtINT interrupts should have ignored the processor priority.
Calling apic_check_pic early in apic_get_interrupt ensures that
apic_deliver_pic_intr is called instead of delivering the spurious
interrupt. apic_deliver_pic_intr then clears CPU_INTERRUPT_HARD if needed.
Reported-by: Richard Bilson <rbilson@qnx.com>
Tested-by: Richard Bilson <rbilson@qnx.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch fixes an obscure failure of the QNX kernel on QEMU x86 SMP.
In QNX, all hardware interrupts come via the PIC, and are delivered by
the cpu 0 LAPIC in ExtINT mode, while IPIs are delivered by the LAPIC
in fixed mode.
This bug happens as follows:
- cpu 0 masks a particular PIC interrupt
- IPI sent to cpu 0 (CPU_INTERRUPT_HARD is set)
- before the IPI is accepted, the masked interrupt line is asserted by the
device
Since the interrupt is masked, apic_deliver_pic_intr will clear
CPU_INTERRUPT_HARD. The IPI will still be set in the APIC irr, but since
CPU_INTERRUPT_HARD is not set the cpu will not notice. Depending on the
scenario this can cause a system hang, i.e. if cpu 0 is expected to unmask
the interrupt.
In order to fix this, do a full check of the APIC before an EXTINT
is acknowledged. This can result in clearing CPU_INTERRUPT_HARD, but
can also result in delivering the lost IPI.
Reported-by: Richard Bilson <rbilson@qnx.com>
Tested-by: Richard Bilson <rbilson@qnx.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
After the next patch, if a masked PIC interrupts causes CPU_INTERRUPT_POLL
to be set, the CPU will spuriously get out of halted state. While this
is technically valid, we should avoid that.
Make CPU_INTERRUPT_POLL run apic_update_irq in the right thread and then
look at CPU_INTERRUPT_HARD. If CPU_INTERRUPT_HARD does not get set,
do not report the CPU as having work.
Also move the handling of software-disabled APIC from apic_update_irq
to apic_irq_pending, and always trigger CPU_INTERRUPT_POLL. This will
be important once we will add a case that resets CPU_INTERRUPT_HARD
from apic_update_irq. We want to run it even if we go through
CPU_INTERRUPT_POLL, and even if the local APIC is software disabled.
Reported-by: Richard Bilson <rbilson@qnx.com>
Tested-by: Richard Bilson <rbilson@qnx.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This reverts commit 000c4dfff4.
The main reason for reverting this commit before the 2.2 release is that
it adds a QAPI interface that we don't want to keep: The 'nocow' flag
doesn't generally make sense for block nodes, but only for the raw-posix
driver. It should therefore be part of ImageInfoSpecific rather than
ImageInfo.
The commit contains more problems, but unlike the API stability issue
they wouldn't justify reverting it.
Conflicts:
block/qapi.c
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Performance wise it's better to align GVA by the backend's
page size.
Also do not allow to create DIMM device with suboptimal
size (i.e. not aligned to backends page size) to aviod
memory loss.
Do above only for 2.2 and newer machine types to avoid
breaking working configs with 2.1 machine type.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
introduce memory_region_get_alignment() that returns
underlying memory block alignment or 0 if it's not
relevant/implemented for backend.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
When running in KVM mode, kvm_set_phys_mem() will silently
fail if registered MemoryRegion address/size is not page
aligned. Causing memory hotplug failure in guest.
Mapping non aligned MemoryRegion in TCG mode 'works', but
sane guest OS still expects page aligned memory module
and fails to initialize it if it's not aligned.
So do not allow non aligned (i.e. valid) address/size
values for DIMM to avoid either KVM failure or guest
issues caused by it.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
split addr initialization from declaration so that
later when new local vars are added property getter
wouldn't drift off of error check.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
When more memory devices are used than available
KVM memory slots, QEMU crashes with:
kvm_alloc_slot: no free slot available
Aborted (core dumped)
Fix this by checking that KVM has a free slot before
attempting to map memory in guest address space.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
tcp_get_fds API discards fds if there's more than 1 of these.
It's tricky to fix this without API changes in the generic case.
However, this API is only used by tests ATM, and tests know how
many fds they expect.
So let's not waste cycles trying to fix this properly:
simply assume at most 16 fds (tests use at most 8 now).
assert if some test tries to get more.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Coverity spot:
Assigning: iov = struct iovec [3]({{buf, 12UL},
{(void *)dot1q_buf, 4UL},
{buf + 12, size - 12}})
(address of temporary variable of type struct iovec [3]).
out_of_scope: Temporary variable of type struct iovec [3] goes out of scope.
Pointer to local outside scope (RETURN_LOCAL)
use_invalid:
Using iov, which points to an out-of-scope temporary variable of type struct iovec [3].
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
s->xmit_pos maybe assigned to a negative value (-1),
but in this branch variable s->xmit_pos as an index to
array s->buffer. Let's add a check for s->xmit_pos.
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
If is_connected parameter is false, the saddr
variable will no initialize. Coverity report:
uninit_use: Using uninitialized value saddr.sin_port.
We don't need add saddr information to nc->info_str
when is_connected is false.
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
commit b412eb61 introduce 'cmd:' target for guestfwd,
and fwd don't be used in this scenario, and will leak
memory in true branch with 'cmd:'. Let's allocate memory
for fwd variable just in else statement.
Cc: Alexander Graf <agraf@suse.de>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This fixes a crash by just skipping the vte resize hack if cur is NULL.
Reproducer:
qemu-system-x86_64 -nodefaults
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
local_err in gd_vc_gfx_init() is not freed, and we don't use it,
so remove it.
Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
ePAPR 1.1 defines the stdout-path property, making the os-specific
linux,stdout-path property redundant. Change the DT setup for ARM virt
to use the generic property - supported by Linux since 3.15.
The old QEMU behaviour was not present in any released version of
QEMU, and was only added to QEMU after the kernel changed, so
this should not break any existing setups.
Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
[PMM: add note to commit about the old behaviour never hving been
in a released version of QEMU]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The Move to Vector Status and Control Register (mtvscr) instruction
uses VRB as the source register. Fix the code generator to correctly
decode the VRB field. That is, use "rB(ctx->opcode)" instead of
"rD(ctx->opcode)".
Signed-off-by: Tom Musta <tommusta@gmail.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Memory slots have to be page aligned to get entered into KVM. There
is existing logic that tries to ensure that we pad memory slots that
are not page aligned to the biggest region that would still fit in the
alignment requirements.
Unfortunately, that logic is broken. It tries to calculate the start
offset based on the region size.
Fix up the logic to do the thing it was intended to do and document it
properly in the comment above it.
With this patch applied, I can successfully run an e500 guest with more
than 3GB RAM (at which point RAM starts overlapping subpage memory regions).
Cc: qemu-stable@nongnu.org
Signed-off-by: Alexander Graf <agraf@suse.de>
In the previous patch, the registers were added to init_proc_G2LE
instead of init_proc_e300.
Signed-off-by: Fabien Chouteau <chouteau@adacore.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
it may actually fix a case where autoconverge would break on a repeat
migration (and not just fix stats).
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Merge remote-tracking branch 'remotes/amit-migration/tags/for-2.2-2' into staging
Fix from a while back that unfortunately got ignored. Dave Gilbert says
it may actually fix a case where autoconverge would break on a repeat
migration (and not just fix stats).
# gpg: Signature made Thu 20 Nov 2014 12:52:41 GMT using RSA key ID 854083B6
# gpg: Good signature from "Amit Shah <amit@amitshah.net>"
# gpg: aka "Amit Shah <amit@kernel.org>"
# gpg: aka "Amit Shah <amitshah@gmx.net>"
* remotes/amit-migration/tags/for-2.2-2:
migration: static variables will not be reset at second migration
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The static variables in migration_bitmap_sync will not be reset in
the case of a second attempted migration.
Signed-off-by: ChenLiang <chenliang88@huawei.com>
Signed-off-by: Gonglei <arei.gonglei@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
The other callers to blk_set_enable_write_cache() in this file
already check for s->blk == NULL.
Signed-off-by: Don Slutz <dslutz@verizon.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1416259239-13281-1-git-send-email-dslutz@verizon.com
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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Merge remote-tracking branch 'remotes/stefanha/tags/net-pull-request' into staging
# gpg: Signature made Tue 18 Nov 2014 15:04:53 GMT using RSA key ID 81AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg: aka "Stefan Hajnoczi <stefanha@gmail.com>"
* remotes/stefanha/tags/net-pull-request:
net: The third parameter of getsockname should be initialized
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
simpletrace.py does not recognize the tcg option while reading trace-events file. In result simpletrace does not work on binary traces and tcg enabled events. Moved transformation of tcg enabled events to _read_events() which is used by simpletrace.
Signed-off-by: Christoph Seifert <christoph.seifert@posteo.de>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Fix the example trace configure option.
Update the text to say that multiple backends are allowed and what
happens when multiple backends are enabled.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 1412691161-31785-1-git-send-email-dgilbert@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
migration by Michael S. Tsirkin.
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Merge remote-tracking branch 'remotes/amit-migration/tags/for-2.2' into staging
Fix for CVE-2014-7840, avoiding arbitrary qemu memory overwrite for
migration by Michael S. Tsirkin.
# gpg: Signature made Tue 18 Nov 2014 11:23:00 GMT using RSA key ID 854083B6
# gpg: Good signature from "Amit Shah <amit@amitshah.net>"
# gpg: aka "Amit Shah <amit@kernel.org>"
# gpg: aka "Amit Shah <amitshah@gmx.net>"
* remotes/amit-migration/tags/for-2.2:
migration: fix parameter validation on ram load
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This updates the Linux header to version 3.18-rc5, adding support for
(among other things) read-only memslots on ARM and arm64.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Message-id: 1416248898-6302-1-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
During migration, the values read from migration stream during ram load
are not validated. Especially offset in host_from_stream_offset() and
also the length of the writes in the callers of said function.
To fix this, we need to make sure that the [offset, offset + length]
range fits into one of the allocated memory regions.
Validating addr < len should be sufficient since data seems to always be
managed in TARGET_PAGE_SIZE chunks.
Fixes: CVE-2014-7840
Note: follow-up patches add extra checks on each block->host access.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
fsync() may fail, and that case should be handled.
Reported-by: László Érsek <lersek@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The loop which filled the file with zeroes may have been left early due
to an error. In that case, the fsync() should be skipped.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
write() may write less bytes than requested; in this case, the number of
bytes written is returned. This is the byte count we should be
subtracting from the number of bytes still to be written, and not the
byte count we requested to write.
Reported-by: László Érsek <lersek@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The code in invalidate_and_set_dirty() needs to handle addr/length
combinations which cross guest physical page boundaries. This can happen,
for example, when disk I/O reads large blocks into guest RAM which previously
held code that we have cached translations for. Unfortunately we were only
checking the clean/dirty status of the first page in the range, and then
were calling a tb_invalidate function which only handles ranges that don't
cross page boundaries. Fix the function to deal with multipage ranges.
The symptoms of this bug were that guest code would misbehave (eg segfault),
in particular after a guest reboot but potentially any time the guest
reused a page of its physical RAM for new code.
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1416167061-13203-1-git-send-email-peter.maydell@linaro.org
* mreitz/block:
raw-posix: The SEEK_HOLE code is flawed, rewrite it
raw-posix: SEEK_HOLE suffices, get rid of FIEMAP
raw-posix: Fix comment for raw_co_get_block_status()
On systems where SEEK_HOLE in a trailing hole seeks to EOF (Solaris,
but not Linux), try_seek_hole() reports trailing data instead.
Additionally, unlikely lseek() failures are treated badly:
* When SEEK_HOLE fails, try_seek_hole() reports trailing data. For
-ENXIO, there's in fact a trailing hole. Can happen only when
something truncated the file since we opened it.
* When SEEK_HOLE succeeds, SEEK_DATA fails, and SEEK_END succeeds,
then try_seek_hole() reports a trailing hole. This is okay only
when SEEK_DATA failed with -ENXIO (which means the non-trailing hole
found by SEEK_HOLE has since become trailing somehow). For other
failures (unlikely), it's wrong.
* When SEEK_HOLE succeeds, SEEK_DATA fails, SEEK_END fails (unlikely),
then try_seek_hole() reports bogus data [-1,start), which its caller
raw_co_get_block_status() turns into zero sectors of data. Could
theoretically lead to infinite loops in code that attempts to scan
data vs. hole forward.
Rewrite from scratch, with very careful comments.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Commit 5500316 (May 2012) implemented raw_co_is_allocated() as
follows:
1. If defined(CONFIG_FIEMAP), use the FS_IOC_FIEMAP ioctl
2. Else if defined(SEEK_HOLE) && defined(SEEK_DATA), use lseek()
3. Else pretend there are no holes
Later on, raw_co_is_allocated() was generalized to
raw_co_get_block_status().
Commit 4f11aa8 (May 2014) changed it to try the three methods in order
until success, because "there may be implementations which support
[SEEK_HOLE/SEEK_DATA] but not [FIEMAP] (e.g., NFSv4.2) as well as vice
versa."
Unfortunately, we used FIEMAP incorrectly: we lacked FIEMAP_FLAG_SYNC.
Commit 38c4d0a (Sep 2014) added it. Because that's a significant
speed hit, the next commit 7c159037 put SEEK_HOLE/SEEK_DATA first.
As you see, the obvious use of FIEMAP is wrong, and the correct use is
slow. I guess this puts it somewhere between -7 "The obvious use is
wrong" and -10 "It's impossible to get right" on Rusty Russel's Hard
to Misuse scale[*].
"Fortunately", the FIEMAP code is used only when
* SEEK_HOLE/SEEK_DATA aren't defined, but CONFIG_FIEMAP is
Uncommon. SEEK_HOLE had no XFS implementation between 2011 (when it
was introduced for ext4 and btrfs) and 2012.
* SEEK_HOLE/SEEK_DATA and CONFIG_FIEMAP are defined, but lseek() fails
Unlikely.
Thus, the FIEMAP code executes rarely. Makes it a nice hidey-hole for
bugs. Worse, bugs hiding there can theoretically bite even on a host
that has SEEK_HOLE/SEEK_DATA.
I don't want to worry about this crap, not even theoretically. Get
rid of it.
[*] http://ozlabs.org/~rusty/index.cgi/tech/2008-04-01.html
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Missed in commit 705be72.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
The ARMv8 address translation system defines that a page table walk
starts at a level which depends on the translation granule size
and the number of bits of virtual address that need to be resolved.
Where the translation granule is 64KB and the guest sets the
TCR.TxSZ field to between 35 and 39, it's actually possible to
start at level 3 (the final level). QEMU's implementation failed
to handle this case, and so we would set level to 2 and behave
incorrectly (including invoking the C undefined behaviour of
shifting left by a negative number). Correct the code that
determines the starting level to deal with the start-at-3 case,
by replacing the if-else ladder with an expression derived from
the ARM ARM pseudocode version.
This error was detected by the Coverity scan, which spotted
the potential shift by a negative number.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1415890569-7454-1-git-send-email-peter.maydell@linaro.org
