Memory hotplug can fail for some combinations of RAM and maxmem when
DDW is enabled in the presence of devices like nec-usb-xhci. DDW depends
on maximum addressable memory returned by guest and this value is currently
being calculated wrongly by the guest kernel routine memory_hotplug_max().
While there is an attempt to fix the guest kernel, this patch works
around the problem within QEMU itself.
memory_hotplug_max() routine in the guest kernel arrives at max
addressable memory by multiplying lmb-size with the lmb-count obtained
from ibm,dynamic-memory property. There are two assumptions here:
- All LMBs are part of ibm,dynamic memory: This is not true for PowerKVM
where only hot-pluggable LMBs are present in this property.
- The memory area comprising of RAM and hotplug region is contiguous: This
needn't be true always for PowerKVM as there can be gap between
boot time RAM and hotplug region.
To work around this guest kernel bug, ensure that ibm,dynamic-memory
has information about all the LMBs (RMA, boot-time LMBs, future
hotpluggable LMBs, and dummy LMBs to cover the gap between RAM and
hotpluggable region).
RMA is represented separately by memory@0 node. Hence mark RMA LMBs
and also the LMBs for the gap b/n RAM and hotpluggable region as
reserved and as having no valid DRC so that these LMBs are not considered
by the guest.
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This ensures that the underlying memory is marked dirty once the transfer
is complete and resolves cache coherency problems under MacOS 9.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
We need the PPC_FEATURE2_HAS_HTM bit in a subsequent patch, so
add the PowerPC AT_HWCAP2 definitions.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Make sure that guests can use the PowerISA 2.07 CPU sPAPR
compatibility mode when they request it and the target CPU
supports it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
When using an olderr PowerISA level, all the upper compatibility
bits have to be enabled, too. For example when we want to run
something in PowerISA 2.05 compatibility mode on POWER8, the bit
for 2.06 has to be set beside the bit for 2.05.
Additionally, to make sure that we do not set bits that are not
supported by the host, we apply a mask with the known-to-be-good
bits here, too.
Signed-off-by: Thomas Huth <thuth@redhat.com>
[dwg: Added some #ifs to fix compile on 32-bit targets]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
When running with KVM, we might be interested in some details
of the host CPU class, too, so provide a function to get the
corresponding CPU class.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The current pcr_mask values are ambiguous: Should these be the mask
that defines valid bits in the PCR register? Or should these rather
indicate which compatibility levels are possible? Anyway, POWER6 and
POWER7 should certainly not use the same values here. So let's
introduce an additional variable "pcr_supported" here which is
used to indicate the valid compatibility levels, and use pcr_mask
to signal the valid bits in the PCR register.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The h_client_architecture_support() function has become quite big
and nested already. So factor out the code that takes care of the
sPAPR compatibility PVRs (which will be modified by the following
patches).
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Commit f9e98e5d7a ("xen/blkif: Avoid double access to
src->nr_segments") didn't go far enough: src->operation is also being
used twice. And nothing was done to prevent the compiler from using the
source side of the copy done by blk_get_request() (granted that's very
unlikely).
Move the barrier()s up, and add another one to blk_get_request().
Note that for completing XSA-155, the barrier() getting added to
blk_get_request() would suffice, and hence the changes to xen_blkif.h
are more like just cleanup. And since, as said, the unpatched code
getting compiled to something vulnerable is very unlikely (and not
observed in practice), this isn't being viewed as a new security issue.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
OpenSSL's libcrypto always defines AES symbols with the same names as
qemu's local aes code. This is problematic when enabling at least curl
as that frequently also uses libcrypto. It might not be noticed when
running, but if you try to statically link, everything falls down.
An example snippet:
LINK qemu-nbd
.../libcrypto.a(aes-x86_64.o): In function 'AES_encrypt':
(.text+0x460): multiple definition of 'AES_encrypt'
crypto/aes.o:aes.c:(.text+0x670): first defined here
.../libcrypto.a(aes-x86_64.o): In function 'AES_decrypt':
(.text+0x9f0): multiple definition of 'AES_decrypt'
crypto/aes.o:aes.c:(.text+0xb30): first defined here
.../libcrypto.a(aes-x86_64.o): In function 'AES_cbc_encrypt':
(.text+0xf90): multiple definition of 'AES_cbc_encrypt'
crypto/aes.o:aes.c:(.text+0xff0): first defined here
collect2: error: ld returned 1 exit status
.../qemu-2.6.0/rules.mak:105: recipe for target 'qemu-nbd' failed
make: *** [qemu-nbd] Error 1
The aes.h header has redefines already for FreeBSD, but go ahead and
enable that for everyone since there's no real good reason to not use
a namespace all the time.
Signed-off-by: Mike Frysinger <vapier@chromium.org>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Otherwise unintended results could happen. For example,
Coverity reports a division by zero in qcrypto_afsplit_hash.
While this cannot really happen, it shows that the contract
of qcrypto_hash_digest_len can be improved.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The secret object tests left some temporary files on disk
when completing. Ensure they are unlink, and rename them
to make it more obvious where they come from.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Give slightly more information when certification loading fails.
Rather than have no information, you now get gnutls's only slightly
less unhelpful error messages.
Signed-off-by: Alex Bligh <alex@alex.org.uk>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This wrapper for machine_usb(current_machine) is not necessary,
replace all usages of usb_enabled() with machine_usb().
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Alexander Graf <agraf@suse.de>
Cc: qemu-arm@nongnu.org
Cc: qemu-ppc@nongnu.org
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-id: 1465419025-21519-3-git-send-email-ehabkost@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Simplify initialization logic by removing the usb_enabled()
check. The USB controller is part of the SoC, so it doesn't make
sense to create a system where it is not present.
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Andrzej Zaborowski <balrogg@gmail.com>
Cc: qemu-arm@nongnu.org,
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1465419025-21519-2-git-send-email-ehabkost@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Use stl_le_p() and ldl_le_p() to read and write data from
buffers, rather than using pointer casts and cpu_to_le32()
for writes and le32_to_cpup() for reads. This:
* avoids lots of casts
* works even if the buffer isn't as aligned as the host would like
* avoids using the *_to_cpup() functions which we want to get rid of
Note that there may still be some places where a pointer from the
guest is cast to a pointer to a host structure; these would also
have to be changed for the device to work on a host CPU which
enforces alignment restrictions.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1465573077-29221-1-git-send-email-peter.maydell@linaro.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This patch changes usb-host behavior in case we hostbus= and hostaddr=
properties are used to identify the usb device in question. Instead of
adding the device to the hotplug watchlist we try to open directly using
the given bus number and device address.
Putting a device specified by hostaddr to the hotplug watchlist isn't
a great idea as the address isn't a fixed property. It changes every
time the device is plugged in. So considering this case as "use the
device at bus:addr _now_" is more sane. Also usb-host will throw errors
in case it can't initialize the host device.
Note: For devices on the hotplug watchlist (hostport or vendorid or
productid specified) qemu continues to ignore errors and keeps
monitoring the usb bus to see if the device eventually shows up.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 1464945175-28939-1-git-send-email-kraxel@redhat.com
Introduce a "xen-load-devices-state" QAPI command that can be used to
load the state of all devices, but not the RAM or the block devices of
the VM.
We only have hmp commands savevm/loadvm, and qmp commands
xen-save-devices-state.
We use this new command for COLO:
1. suspend both primary vm and secondary vm
2. sync the state
3. resume both primary vm and secondary vm
In such case, we need to update all devices' state in any time.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Since f615f39 (exec: remove ram_addr argument from
qemu_ram_block_from_host), migration under Xen is likely to fail, with a
SEGV of QEMU. But the commit only reveal a bug with the calculation of
the offset value in qemu_ram_block_from_host().
This patch calculates the offset from the ram_addr as
qemu_ram_addr_from_host() will later calculate the ram_addr from the
offset.
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Having a fixed-size hash table for keeping track of all translation blocks
is suboptimal: some workloads are just too big or too small to get maximum
performance from the hash table. The MRU promotion policy helps improve
performance when the hash table is a little undersized, but it cannot
make up for severely undersized hash tables.
Furthermore, frequent MRU promotions result in writes that are a scalability
bottleneck. For scalability, lookups should only perform reads, not writes.
This is not a big deal for now, but it will become one once MTTCG matures.
The appended fixes these issues by using qht as the implementation of
the TB hash table. This solution is superior to other alternatives considered,
namely:
- master: implementation in QEMU before this patchset
- xxhash: before this patch, i.e. fixed buckets + xxhash hashing + MRU.
- xxhash-rcu: fixed buckets + xxhash + RCU list + MRU.
MRU is implemented here by adding an intermediate struct
that contains the u32 hash and a pointer to the TB; this
allows us, on an MRU promotion, to copy said struct (that is not
at the head), and put this new copy at the head. After a grace
period, the original non-head struct can be eliminated, and
after another grace period, freed.
- qht-fixed-nomru: fixed buckets + xxhash + qht without auto-resize +
no MRU for lookups; MRU for inserts.
The appended solution is the following:
- qht-dyn-nomru: dynamic number of buckets + xxhash + qht w/ auto-resize +
no MRU for lookups; MRU for inserts.
The plots below compare the considered solutions. The Y axis shows the
boot time (in seconds) of a debian jessie image with arm-softmmu; the X axis
sweeps the number of buckets (or initial number of buckets for qht-autoresize).
The plots in PNG format (and with errorbars) can be seen here:
http://imgur.com/a/Awgnq
Each test runs 5 times, and the entire QEMU process is pinned to a
single core for repeatability of results.
Host: Intel Xeon E5-2690
28 ++------------+-------------+-------------+-------------+------------++
A***** + + + master **A*** +
27 ++ * xxhash ##B###++
| A******A****** xxhash-rcu $$C$$$ |
26 C$$ A******A****** qht-fixed-nomru*%%D%%%++
D%%$$ A******A******A*qht-dyn-mru A*E****A
25 ++ %%$$ qht-dyn-nomru &&F&&&++
B#####% |
24 ++ #C$$$$$ ++
| B### $ |
| ## C$$$$$$ |
23 ++ # C$$$$$$ ++
| B###### C$$$$$$ %%%D
22 ++ %B###### C$$$$$$C$$$$$$C$$$$$$C$$$$$$C$$$$$$C
| D%%%%%%B###### @E@@@@@@ %%%D%%%@@@E@@@@@@E
21 E@@@@@@E@@@@@@F&&&@@@E@@@&&&D%%%%%%B######B######B######B######B######B
+ E@@@ F&&& + E@ + F&&& + +
20 ++------------+-------------+-------------+-------------+------------++
14 16 18 20 22 24
log2 number of buckets
Host: Intel i7-4790K
14.5 ++------------+------------+-------------+------------+------------++
A** + + + master **A*** +
14 ++ ** xxhash ##B###++
13.5 ++ ** xxhash-rcu $$C$$$++
| qht-fixed-nomru %%D%%% |
13 ++ A****** qht-dyn-mru @@E@@@++
| A*****A******A****** qht-dyn-nomru &&F&&& |
12.5 C$$ A******A******A*****A****** ***A
12 ++ $$ A*** ++
D%%% $$ |
11.5 ++ %% ++
B### %C$$$$$$ |
11 ++ ## D%%%%% C$$$$$ ++
| # % C$$$$$$ |
10.5 F&&&&&&B######D%%%%% C$$$$$$C$$$$$$C$$$$$$C$$$$$C$$$$$$ $$$C
10 E@@@@@@E@@@@@@B#####B######B######E@@@@@@E@@@%%%D%%%%%D%%%###B######B
+ F&& D%%%%%%B######B######B#####B###@@@D%%% +
9.5 ++------------+------------+-------------+------------+------------++
14 16 18 20 22 24
log2 number of buckets
Note that the original point before this patch series is X=15 for "master";
the little sensitivity to the increased number of buckets is due to the
poor hashing function in master.
xxhash-rcu has significant overhead due to the constant churn of allocating
and deallocating intermediate structs for implementing MRU. An alternative
would be do consider failed lookups as "maybe not there", and then
acquire the external lock (tb_lock in this case) to really confirm that
there was indeed a failed lookup. This, however, would not be enough
to implement dynamic resizing--this is more complex: see
"Resizable, Scalable, Concurrent Hash Tables via Relativistic
Programming" by Triplett, McKenney and Walpole. This solution was
discarded due to the very coarse RCU read critical sections that we have
in MTTCG; resizing requires waiting for readers after every pointer update,
and resizes require many pointer updates, so this would quickly become
prohibitive.
qht-fixed-nomru shows that MRU promotion is advisable for undersized
hash tables.
However, qht-dyn-mru shows that MRU promotion is not important if the
hash table is properly sized: there is virtually no difference in
performance between qht-dyn-nomru and qht-dyn-mru.
Before this patch, we're at X=15 on "xxhash"; after this patch, we're at
X=15 @ qht-dyn-nomru. This patch thus matches the best performance that we
can achieve with optimum sizing of the hash table, while keeping the hash
table scalable for readers.
The improvement we get before and after this patch for booting debian jessie
with arm-softmmu is:
- Intel Xeon E5-2690: 10.5% less time
- Intel i7-4790K: 5.2% less time
We could get this same improvement _for this particular workload_ by
statically increasing the size of the hash table. But this would hurt
workloads that do not need a large hash table. The dynamic (upward)
resizing allows us to start small and enlarge the hash table as needed.
A quick note on downsizing: the table is resized back to 2**15 buckets
on every tb_flush; this makes sense because it is not guaranteed that the
table will reach the same number of TBs later on (e.g. most bootup code is
thrown away after boot); it makes sense to grow the hash table as
more code blocks are translated. This also avoids the complication of
having to build downsizing hysteresis logic into qht.
Reviewed-by: Sergey Fedorov <serge.fedorov@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1465412133-3029-15-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
This is a fast, scalable chained hash table with optional auto-resizing, allowing
reads that are concurrent with reads, and reads/writes that are concurrent
with writes to separate buckets.
A hash table with these features will be necessary for the scalability
of the ongoing MTTCG work; before those changes arrive we can already
benefit from the single-threaded speedup that qht also provides.
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1465412133-3029-11-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Sometimes it is useful to have a quick histogram to represent a certain
distribution -- for example, when investigating a performance regression
in a hash table due to inadequate hashing.
The appended allows us to easily represent a distribution using Unicode
characters. Further, the data structure keeping track of the distribution
is so simple that obtaining its values for off-line processing is trivial.
Example, taking the last 10 commits to QEMU:
Characters in commit title Count
-----------------------------------
39 1
48 1
53 1
54 2
57 1
61 1
67 1
78 1
80 1
qdist_init(&dist);
qdist_inc(&dist, 39);
[...]
qdist_inc(&dist, 80);
char *str = qdist_pr(&dist, 9, QDIST_PR_LABELS);
// -> [39.0,43.6)▂▂ █▂ ▂ ▄[75.4,80.0]
g_free(str);
char *str = qdist_pr(&dist, 4, QDIST_PR_LABELS);
// -> [39.0,49.2)▁█▁▁[69.8,80.0]
g_free(str);
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1465412133-3029-9-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
For some workloads such as arm bootup, tb_phys_hash is performance-critical.
The is due to the high frequency of accesses to the hash table, originated
by (frequent) TLB flushes that wipe out the cpu-private tb_jmp_cache's.
More info:
https://lists.nongnu.org/archive/html/qemu-devel/2016-03/msg05098.html
To dig further into this I modified an arm image booting debian jessie to
immediately shut down after boot. Analysis revealed that quite a bit of time
is unnecessarily spent in tb_phys_hash: the cause is poor hashing that
results in very uneven loading of chains in the hash table's buckets;
the longest observed chain had ~550 elements.
The appended addresses this with two changes:
1) Use xxhash as the hash table's hash function. xxhash is a fast,
high-quality hashing function.
2) Feed the hashing function with not just tb_phys, but also pc and flags.
This improves performance over using just tb_phys for hashing, since that
resulted in some hash buckets having many TB's, while others getting very few;
with these changes, the longest observed chain on a single hash bucket is
brought down from ~550 to ~40.
Tests show that the other element checked for in tb_find_physical,
cs_base, is always a match when tb_phys+pc+flags are a match,
so hashing cs_base is wasteful. It could be that this is an ARM-only
thing, though. UPDATE:
On Tue, Apr 05, 2016 at 08:41:43 -0700, Richard Henderson wrote:
> The cs_base field is only used by i386 (in 16-bit modes), and sparc (for a TB
> consisting of only a delay slot).
> It may well still turn out to be reasonable to ignore cs_base for hashing.
BTW, after this change the hash table should not be called "tb_hash_phys"
anymore; this is addressed later in this series.
This change gives consistent bootup time improvements. I tested two
host machines:
- Intel Xeon E5-2690: 11.6% less time
- Intel i7-4790K: 19.2% less time
Increasing the number of hash buckets yields further improvements. However,
using a larger, fixed number of buckets can degrade performance for other
workloads that do not translate as many blocks (600K+ for debian-jessie arm
bootup). This is dealt with later in this series.
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1465412133-3029-8-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
This will be used by upcoming changes for hashing the tb hash.
Add this into a separate file to include the copyright notice from
xxhash.
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1465412133-3029-7-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Signed-off-by: Guillaume Delbergue <guillaume.delbergue@greensocs.com>
[Rewritten. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[Emilio's additions: use TAS instead of atomic_xchg; emit acquire/release
barriers; return bool from trylock; call cpu_relax() while spinning;
optimize for uncontended locks by acquiring the lock with TAS instead
of TATAS; add qemu_spin_locked().]
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1465412133-3029-6-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Taken from the linux kernel.
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1465412133-3029-5-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
It is a more appropriate name, now that the mutex embedded
in the seqlock is gone.
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1465412133-3029-4-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
This option is unused; besides, it bloats the struct when not needed.
Let's just let writers define their own locks elsewhere.
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1465412133-3029-3-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
If VNC is chosen as the compile time default display backend,
QEMU will print the host/port it listens on at startup.
Previously this would look like
VNC server running on '::1:5900'
but in 04d2529da2 the ':' was
accidentally replaced with a ';'. This the ':' back.
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1465382576-25552-1-git-send-email-berrange@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The exception_action() function in user-exec.c is just a call to
cpu_loop_exit() for every target CPU except i386. Since this
function is only called if the target's handle_mmu_fault() hook has
indicated an MMU fault, and that hook is only called from the
handle_cpu_signal() code path, we can simply move the x86-specific
setup into that hook, which allows us to remove the TARGET_I386
ifdef from user-exec.c.
Of the actions that were done by the call to raise_interrupt_err():
* cpu_svm_check_intercept_param() is a no-op in user mode
* check_exception() is a no-op since double faults are impossible
for user-mode
* assignments to cs->exception_index and env->error_code are no-ops
* assigning to env->exception_next_eip is unnecessary because it
is not used unless env->exception_is_int is true
* cpu_loop_exit_restore() is equivalent to cpu_loop_exit() since
pc is 0
which leaves just setting env_>exception_is_int as the action that
needs to be added to x86_cpu_handle_mmu_fault().
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Acked-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Riku Voipio <riku.voipio@linaro.org>
Message-id: 1463494687-25947-7-git-send-email-peter.maydell@linaro.org
Add a comment to do_interrupt_user() along the same lines as the
existing one for do_interrupt_all() noting that the next_eip
argument is not used unless is_int is true or intno is EXCP_SYSCALL.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Acked-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Riku Voipio <riku.voipio@linaro.org>
Message-id: 1463494687-25947-6-git-send-email-peter.maydell@linaro.org
Extracting the old signal mask from the usercontext pointer passed to
a signal handler is a pain because it is OS and CPU dependent.
Since we've already done it once and passed it to handle_cpu_signal(),
there's no need to do it again in cpu_exit_tb_from_sighandler().
This then means we don't need to pass a usercontext pointer in to
handle_cpu_signal() at all.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Acked-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Riku Voipio <riku.voipio@linaro.org>
Message-id: 1463494687-25947-5-git-send-email-peter.maydell@linaro.org
The function cpu_resume_from_signal() is now always called with a
NULL puc argument, and is rather misnamed since it is never called
from a signal handler. It is essentially forcing an exit to the
top level cpu loop but without raising any exception, so rename
it to cpu_loop_exit_noexc() and drop the useless unused argument.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Acked-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Riku Voipio <riku.voipio@linaro.org>
Message-id: 1463494687-25947-4-git-send-email-peter.maydell@linaro.org
Since the only caller of page_unprotect() which might cause it to
need to call cpu_resume_from_signal() is handle_cpu_signal() in
the user-mode code, push the longjump handling out to that function.
Since this is the only caller of cpu_resume_from_signal() which
passes a non-NULL puc argument, split the non-NULL handling into
a new cpu_exit_tb_from_sighandler() function. This allows us
to merge the softmmu and usermode implementations of the
cpu_resume_from_signal() function, which are now identical.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Acked-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Riku Voipio <riku.voipio@linaro.org>
Message-id: 1463494687-25947-3-git-send-email-peter.maydell@linaro.org
The user-mode-only function tb_invalidate_phys_page() is only
called from two places:
* page_unprotect(), which passes in a non-zero pc, a puc pointer
and the value 'true' for the locked argument
* page_set_flags(), which passes in a zero pc, a NULL puc pointer
and a 'false' locked argument
If the pc is non-zero then we may call cpu_resume_from_signal(),
which does a longjmp out of the calling code (and out of the
signal handler); this is to cover the case of a target CPU with
"precise self-modifying code" (currently only x86) executing
a store instruction which modifies code in the same TB as the
store itself. Rather than doing the longjump directly here,
return a flag to the caller which indicates whether the current
TB was modified, and move the longjump to page_unprotect.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Acked-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Riku Voipio <riku.voipio@linaro.org>
Message-id: 1463494687-25947-2-git-send-email-peter.maydell@linaro.org
