aboutsummaryrefslogtreecommitdiff
AgeCommit message (Collapse)Author
2012-03-13usb-ohci: DMA writeback bug fixesWei Yang
This patch fixes two bugs in the OHCI device where the device writes back data to system memory that should be exclusively under the control of the guest side driver. In OHCI specification Section 5.2.7, it mentioned "In all cases, Host Controller Driver is responsible for the insertion and removal of all Endpoint Descriptors in the various Host Controller Endpoint Descriptor lists". In the ohci_frame_boundary(), ohci_put_hcca() writes the entire hcca back including the interrupt ED lists which should be under driver control. This violates the specification and can race with a host driver updating that list at the same time. In the OHCI Spec Section 4.6, Transfer Descriptor Queue Processing, it mentioned "Since the TD pointed to by TailP is not accessed by the HC, the Host Controller Driver can initialize that TD and link at least one other to it without creating a coherency or synchronization problem". While the function ohci_put_ed() writes the entire endpoint descriptor back including the TailP which should under driver control. This violate the specification and can race with a host driver updating the TD list at the same time. In each case the solution is to make sure we don't write data which is under driver control. Cc: Gerd Hoffman <kraxel@redhat.com> Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com> Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2012-03-13usb-ehci: drop unused isoch_pause variableHans de Goede
Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2012-03-13usb: zap hw/ush-{ohic,uhci}.h + init wrappersGerd Hoffmann
Remove the uhci and ohci init wrappers, which all wrapped a pci_create_simple() one-liner. Switch callsites to call pci_create_simple directly. Remove the header files where the wrappers where declared. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2012-03-13usb: the big renameGerd Hoffmann
Reorganize usb source files. Create a new hw/usb/ directory and move all usb source code to that place. Also make filenames a bit more descriptive. Host adapters are prefixed with "hch-" now, usb device emulations are prefixed with "dev-". Fixup paths Makefile and include paths to make it compile. No code changes. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
2012-03-12Merge remote-tracking branch 'mdroth/qga-pull-3-12-2012' into stagingAnthony Liguori
* mdroth/qga-pull-3-12-2012: qemu-ga: add guest-sync-delimited qemu-ga: add guest-network-get-interfaces command qemu-ga: add win32 guest-suspend-ram command qemu-ga: add win32 guest-suspend-disk command. qemu-ga: add guest-suspend-hybrid qemu-ga: add guest-suspend-ram qemu-ga: add guest-suspend-disk
2012-03-12Merge remote-tracking branch 'kwolf/for-anthony' into stagingAnthony Liguori
* kwolf/for-anthony: test-coroutine: add performance test for nesting coroutine: adding configure option for sigaltstack coroutine backend coroutine: adding configure choose mechanism for coroutine backend coroutine: adding sigaltstack method (.c source) qcow2: Reduce number of I/O requests qcow2: Add qcow2_alloc_clusters_at() qcow2: Factor out count_cow_clusters qmp: convert blockdev-snapshot-sync to a wrapper around transactions add mode field to blockdev-snapshot-sync transaction item rename blockdev-group-snapshot-sync qapi: complete implementation of unions use QSIMPLEQ_FOREACH_SAFE when freeing list elements Add 'make check-block' make check: Add qemu-iotests subset qemu-iotests: Mark some tests as quick qcow2: Add error messages in qcow2_truncate block: handle -EBUSY in bdrv_commit_all() qcow2: Add some tracing qed: do not evict in-use L2 table cache entries Group snapshot: Fix format name for backing file
2012-03-12Merge remote-tracking branch 'qemu-kvm/memory/core' into stagingAnthony Liguori
* qemu-kvm/memory/core: memory: get rid of cpu_register_io_memory() memory: dispatch directly via MemoryRegion exec: fix code tlb entry misused as iotlb in get_page_addr_code() memory: store section indices in iotlb instead of io indices memory: make phys_page_find() return an unadjusted section
2012-03-12Merge remote-tracking branch 'stefanha/tracing' into stagingAnthony Liguori
* stefanha/tracing: vga: add trace event for ppm_save console: add some trace events maintainers: Add docs/tracing.txt to Tracing docs: correct ./configure line in tracing.txt trace: make trace_thread_create() use its function arg tracetool: Omit useless QEMU_*_ENABLED() check trace: Provide a per-event status define for conditional compilation
2012-03-12Merge remote-tracking branch 'qmp/queue/qmp' into stagingAnthony Liguori
* qmp/queue/qmp: qapi-schema.json: fix comment for type ObjectPropretyInfo qapi-schema: fix typos and explain 'spice' auth qjson.h: include compiler.h for GCC_FMT_ATTR
2012-03-12qemu-ga: add guest-sync-delimitedMichael Roth
guest-sync leaves it as an exercise to the user as to how to reliably obtain the response to guest-sync if the client had previously read in a partial response (due qemu-ga previously being restarted mid-"sentence" due to reboot, forced restart, etc). qemu-ga handles this situation on its end by having a client precede their guest-sync request with a 0xFF byte (invalid UTF-8), which qemu-ga/QEMU JSON parsers will treat as a flush event. Thus we can reliably flush the qemu-ga parser state in preparation for receiving the guest-sync request. guest-sync-delimited provides the same functionality for a client: when a guest-sync-delimited is issued, qemu-ga will precede it's response with a 0xFF byte that the client can use as an indicator to flush its buffer/parser state in preparation for reliably receiving the guest-sync-delimited response. It is also useful as an optimization for clients, since, after issuing a guest-sync-delimited, clients can safely discard all stale data read from the channel until the 0xFF is found. More information available on the wiki: http://wiki.qemu.org/Features/QAPI/GuestAgent#QEMU_Guest_Agent_Protocol Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
2012-03-12qemu-ga: add guest-network-get-interfaces commandMichal Privoznik
This command returns an array of: [ifname, hwaddr, [ipaddr, ipaddr_family, prefix] ] for each interface in the system. Currently, only IPv4 and IPv6 are supported. Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2012-03-12qemu-ga: add win32 guest-suspend-ram commandMichael Roth
S3 sleep implementation for windows.
2012-03-12qemu-ga: add win32 guest-suspend-disk command.Gal Hammer
Implement guest-suspend-disk RPC for Windows. Functionally this should be equivalent to the posix implementation. Signed-off-by: Gal Hammer <ghammer@redhat.com>
2012-03-12qemu-ga: add guest-suspend-hybridLuiz Capitulino
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2012-03-12qemu-ga: add guest-suspend-ramLuiz Capitulino
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2012-03-12qemu-ga: add guest-suspend-diskLuiz Capitulino
As the command name implies, this command suspends the guest to disk. The suspend operation is implemented by two functions: bios_supports_mode() and guest_suspend(). Both functions are generic enough to be used by other suspend modes (introduced by next commits). Both functions will try to use the scripts provided by the pm-utils package if it's available. If it's not available, a manual method, which consists of directly writing to '/sys/power/state', will be used. To reap terminated children, a new signal handler is installed in the parent to catch SIGCHLD signals and a non-blocking call to waitpid() is done to collect their exit statuses. The statuses, however, are discarded. The approach used to query the guest for suspend support deserves some explanation. It's implemented by bios_supports_mode() and shown below: qemu-ga | create pipe | fork() ----------------- | | | | | fork() | -------------------------- | | | | | | | | exec('pm-is-supported') | | | wait() | write exit status to pipe | exit | read pipe This might look complex, but the resulting code is quite simple. The purpose of that approach is to allow qemu-ga to reap its children (semi-)automatically from its SIGCHLD handler. Implementing this the obvious way, that's, doing the exec() call from the first child process, would force us to introduce a more complex way to reap qemu-ga's children. Like registering PIDs to be reaped and having a way to wait for them when returning their exit status to qemu-ga is necessary. The approach explained above avoids that complexity. Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2012-03-12cpu-all.h: Don't accidentally sign extend in g2h()Peter Maydell
Cast the argument of the g2h() macro to a target_ulong so that it isn't accidentally sign-extended if it is a signed 32 bit type and long is a 64 bit type. In particular, this fixes a bug where it would return the wrong value for 32 bit guests on 64 bit hosts when passed in one of the arg* values from do_syscall() [which are all abi_long and thus signed types]. This could result in spurious failure of mlock(), among others. Reviewed-by: Andreas F=E4rber <afaerber@suse.de> Signed-off-by: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-03-12implement vnc_dpy_setdataGerd Hoffmann
The comment is wrong, we have to do something in the setdata callback. Changing the framebuffer backing storage (happens when the guest pans the display) renders the whole screen content invalid. Trigger #1: cirrus vga + 32bit linux guest + vesafb with ypan enabled. Trigger #2: std vga + http://patchwork.ozlabs.org/patch/145479/ Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-03-12initialize CPU model list after handling -readconfig optionsEduardo Habkost
To properly load cpudefs using -readconfig, we have to call cpudef_init() after finishing the command-line option handling. Consequently, the handling of "-cpu ?" has to be done after the command-line option handling loop, too. Without this patch, "-readconfig configfile -cpu ?" fails to list the CPU definitions read from 'configfile'. Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-03-12add Opteron_G4 CPU model (v2)Eduardo Habkost
This patch addes a Bulldozer-based Opteron_G4 CPU model. This version has the ffxsr bit actually disabled, to match what was documented below. Thanks to Andre Przywara for spotting the bug. I am trying to be conservative with the new model, so I am enabling only features known to be useful to guests, and not enabling anything that was not tested or found to be useful to a guest. List of missing flags in comparison to real hardware: - vme: host-specific feature. - osxsave: it is not set here because it is set by the guest OS, not by KVM - monitor: this is filtered out by the KVM module, so no point in enabling it. - mmxext: untested, so not enabled. - Perf*, Topology*, lwp, ibs: not emulated by KVM. - wdt, skinit, osvw, altmovcr8, extapicspace, cmplegacy: untested, so not enabled. List of new flags, in comparison to the Opteron_G3 model: - xsave: xsave feature, already implemented by Qemu - avx, aes, sse4.x, ssse3, pclmulqdq: all new state the new instructions could use is handled by the xsave state loading/saving code on Qemu. - pdpe1gb: 1GB pages, supported by the KVM kernel module. - ffxsr: untested, so not enabled - fma4, xop: all new state the new instructions could use is handled by the xsave loading/saving code on Qemu. - 3dnowprefetch: safe to pass through, though the flag is not used by Linux guests, at least. Below is the comparison between the current Opteron_G3 model and the new model being added. - The "full" line contains the flags found on actual hardware. - The "missing" line shows the flags that are present on actual hardware, but not on the added Opteron_G4 model. - The "new" line shows the flags that were not on the Opteron_G3 model but are on Opteron_G4. feature_edx: Opteron_G3: sse2 sse fxsr mmx clflush pse36 pat cmov mca pge mtrr sep apic cx8 mce pae msr tsc pse de fpu full: sse2 sse fxsr mmx clflush pse36 pat cmov mca pge mtrr sep apic cx8 mce pae msr tsc pse de vme fpu Opteron_G4: sse2 sse fxsr mmx clflush pse36 pat cmov mca pge mtrr sep apic cx8 mce pae msr tsc pse de fpu missing: vme feature_ecx: Opteron_G3: popcnt cx16 monitor sse3 full: avx osxsave xsave aes popcnt sse4.2 sse4.1 cx16 ssse3 monitor pclmulqdq sse3 Opteron_G4: avx xsave aes popcnt sse4.2 sse4.1 cx16 ssse3 pclmulqdq sse3 missing: osxsave monitor new: avx xsave aes sse4.2 sse4.1 ssse3 pclmulqdq extfeature_edx: Opteron_G3: lm rdtscp fxsr mmx nx pse36 pat cmov mca pge mtrr syscall apic cx8 mce pae msr tsc pse de fpu full: lm rdtscp pdpe1gb ffxsr fxsr mmx mmxext nx pse36 pat cmov mca pge mtrr syscall apic cx8 mce pae msr tsc pse de vme fpu Opteron_G4: lm rdtscp pdpe1gb fxsr mmx nx pse36 pat cmov mca pge mtrr syscall apic cx8 mce pae msr tsc pse de fpu missing: mmxext vme new: pdpe1gb extfeature_ecx: Opteron_G3: misalignsse sse4a abm svm lahf_lm full: Perf* Topology* fma4 lwp wdt skinit xop ibs osvw 3dnowprefetch misalignsse sse4a abm altmovcr8 extapicspace svm cmplegacy lahf_lm Opteron_G4: fma4 xop 3dnowprefetch misalignsse sse4a abm svm lahf_lm new: fma4 xop 3dnowprefetch missing: Perf* Topology* lwp wdt skinit ibs osvw altmovcr8 extapicspace cmplegacy Changes v1 -> v2: - Actually disable ffxsr bit Cc: Andre Przywara <andre.przywara@amd.com> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-03-12add SandyBridge CPU modelEduardo Habkost
This patches add the definition of a SandyBridge CPU model. Summary of differences: Flags present on actual hardware, but not on the added model definition: - pbe, tm, ht, ss, acpi, vme, xTPR, tm2, eist, smx: host-specific features, not exposed to guest. - ds, ds-cpl, dtes64, pdcm: emulation not supported by KVM (although it may be added in the future if implementing PMU virtualization) - pcid, vmx, monitor: not emulated by Qemu/KVM right now. - osxsave: set by the guest OS, not by Qemu. Flags added, that were not present on Westmere model: - xsave: already supported by Qemu - avx, pclmulqdq: all new state the new instructions could use is handled by xsave state loading/saving code. - tsc-deadline, x2apic, rdtscp: already supported by Qemu/KVM. Below there's a comparison of the features on the current Westmere CPU model, and the SandyBridge CPU model. - The "full" line contains the flags found on actual hardware. - The "missing" line shows the flags that are present on actual hardware, but not on the added SandyBridge model. - The "new" line shows the flags that were not on the Westmere model, but are on SandyBridge. feature_edx: Westmere: sse2 sse fxsr mmx clflush pse36 pat cmov mca pge mtrr sep apic cx8 mce pae msr tsc pse de fpu full: pbe tm ht ss sse2 sse fxsr mmx ds acpi clflush pse36 pat cmov mca pge mtrr sep apic cx8 mce pge msr tsc pse de vme fpu SandyBridge: sse2 sse fxsr mmx clflush pse36 pat cmov mca pge mtrr sep apic cx8 mce pae msr tsc pse de fpu missing: pbe tm ht ss ds acpi vme feature_ecx: Westmere: aes popcnt sse4.2 sse4.1 cx16 ssse3 sse3 full: avx osxsave xsave aes tsc-deadline popcnt x2apic sse4.2 sse4.1 pcid pdcm xTPR cx16 ssse3 tm2 eist smx vmx ds-cpl monitor dtes64 pclmulqdq sse3 SandyBridge: avx xsave aes tsc-deadline popcnt x2apic sse4.2 sse4.1 cx16 ssse3 pclmulqdq sse3 missing: osxsave pcid pdcm xTPR tm2 eist smx vmx ds-cpl monitor dtes64 new: avx xsave tsc-deadline x2apic pclmulqdq extfeature_edx: Westmere: i64 nx syscall full: i64 rdtscp nx syscall SandyBridge: i64 rdtscp nx syscall new: rdtscp extfeature_ecx: Westmere: lahf_lm full: lahf_lm SandyBridge: lahf_lm Cc: "Dugger, Donald D" <donald.d.dugger@intel.com> Cc: "Zhang, Xiantao" <xiantao.zhang@intel.com> Acked-by: Xiantao Zhang <xiantao.zhang@intel.com> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-03-12add "tsc-deadline" flag name to feature_ecx tableEduardo Habkost
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-03-12qom: fix device hot-unplugPaolo Bonzini
Property removal modifies the list, so it is not safe to continue iteration. We know anyway that each object can have only one parent (see object_property_add_child), so exit after finding the requested object. Reported-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-03-12qdev: accept empty string propertiesPaolo Bonzini
These were stored as NULL due to wrong cut-and-paste from set_pointer. Reported-by: Gerhard Wiesinger <lists@wiesinger.com> Tested-by: Gerhard Wiesinger <lists@wiesinger.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-03-12test-coroutine: add performance test for nestingAlex Barcelo
The performance test will also check for nesting. It will do a certain quantity of cycles, and each of one will do a depth nesting process. This is useful for benchmarking the creation of coroutines, given that nesting is creation-intensive (and the other perf test does not benchmark that). Signed-off-by: Alex Barcelo <abarcelo@ac.upc.edu> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12coroutine: adding configure option for sigaltstack coroutine backendAlex Barcelo
It's possible to use sigaltstack backend with --with-coroutine=sigaltstack v2: changed from enable/disable configure flags Signed-off-by: Alex Barcelo <abarcelo@ac.upc.edu> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12coroutine: adding configure choose mechanism for coroutine backendAlex Barcelo
Configure tries, as a default, ucontext functions for the coroutines. But now the user can force another backend by --with-coroutine=BACKEND option v2: Using --with-coroutine=BACKEND instead of enable disable individual configure options Signed-off-by: Alex Barcelo <abarcelo@ac.upc.edu> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12coroutine: adding sigaltstack method (.c source)Alex Barcelo
This file is based in both coroutine-ucontext.c and pth_mctx.c (from the GNU Portable Threads library). The mechanism used to change stacks is the sigaltstack function (variant 2 of the pth library). v2: Some corrections. Moving global variables into thread storage (CoroutineThreadState). Signed-off-by: Alex Barcelo <abarcelo@ac.upc.edu> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12qcow2: Reduce number of I/O requestsKevin Wolf
If the first part of a write request is allocated, but the second isn't and it can be allocated so that the resulting area is contiguous, handle it at once. This is a common case for sequential writes. After this patch, alloc_cluster_offset() only checks if the clusters are already allocated or how many new clusters can be allocated contigouosly. The actual cluster allocation is split off into a new function do_alloc_cluster_offset(). Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-03-12qcow2: Add qcow2_alloc_clusters_at()Kevin Wolf
This function allows to allocate clusters at a given offset in the image file. This is useful if you want to allocate the second part of an area that must be contiguous. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-03-12qcow2: Factor out count_cow_clustersKevin Wolf
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-03-12qmp: convert blockdev-snapshot-sync to a wrapper around transactionsPaolo Bonzini
Simplify the blockdev-snapshot-sync code and gain failsafe operation by turning it into a wrapper around the new transaction command. A new option is also added matching "mode". Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12add mode field to blockdev-snapshot-sync transaction itemPaolo Bonzini
The mode field lets a management application create the snapshot destination outside QEMU. Right now, the only modes are "existing" and "absolute-paths". Mirroring introduces "no-backing-file". In the future "relative-paths" could be implemented too. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12rename blockdev-group-snapshot-syncPaolo Bonzini
We will add other kinds of operation. Prepare for this by adjusting the schema. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12qapi: complete implementation of unionsPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Luiz Capitulino <lcapitulino@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12use QSIMPLEQ_FOREACH_SAFE when freeing list elementsPaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12Add 'make check-block'Kevin Wolf
Runs the full qemu-iotests suite for various image formats. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12make check: Add qemu-iotests subsetKevin Wolf
Run the 'quick' group from qemu-iotests during 'make check'. Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12qemu-iotests: Mark some tests as quickKevin Wolf
This creates a new test group 'quick' for some test case that take at most a couple of seconds each, so that the group can be run during a quick 'make check' Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12qcow2: Add error messages in qcow2_truncateKevin Wolf
qemu-img resize has some limitations with qcow2, but the user is only told that "this image format does not support resize". Quite confusing, so add some more detailed error_report() calls and change "this image format" into "this image". Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-03-12block: handle -EBUSY in bdrv_commit_all()Stefan Hajnoczi
Monitor operations that manipulate image files must not execute while a background job (like image streaming) is in progress. This prevents corruptions from happening when two pieces of code are manipulating the image file without knowledge of each other. The monitor "commit" command raises QERR_DEVICE_IN_USE when bdrv_commit() returns -EBUSY but "commit all" has no error handling. This is easy to fix, although note that we do not deliver a detailed error about which device was busy in the "commit all" case. Suggested-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12qcow2: Add some tracingKevin Wolf
Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-03-12qed: do not evict in-use L2 table cache entriesStefan Hajnoczi
The L2 table cache reduces QED metadata reads that would be required when translating LBAs to offsets into the image file. Since requests execute in parallel it is possible to share an L2 table between multiple requests. There is a potential data corruption issue when an in-use L2 table is evicted from the cache because the following situation occurs: 1. An allocating write performs an update to L2 table "A". 2. Another request needs L2 table "B" and causes table "A" to be evicted. 3. A new read request needs L2 table "A" but it is not cached. As a result the L2 update from #1 can overlap with the L2 fetch from #3. We must avoid doing overlapping I/O requests here since the worst case outcome is that the L2 fetch completes before the L2 update and yields stale data. In that case we would effectively discard the L2 update and lose data clusters! Thanks to Benoît Canet <benoit.canet@gmail.com> for extensive testing and debugging which lead to discovery of this bug. Reported-by: Benoît Canet <benoit.canet@gmail.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Tested-by: Benoît Canet <benoit.canet@gmail.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12Group snapshot: Fix format name for backing filePaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2012-03-12vga: add trace event for ppm_saveAlon Levy
Signed-off-by: Alon Levy <alevy@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-03-12console: add some trace eventsAlon Levy
Signed-off-by: Alon Levy <alevy@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-03-12maintainers: Add docs/tracing.txt to TracingAndreas Färber
The topic of whether and by whom docs/tracing.txt is maintained was brought up. It currently does not have an official maintainer. Add it to the tracing section so that Stefan gets cc'ed on patches. Signed-off-by: Andreas Färber <afaerber@suse.de> Acked-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Cc: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-03-12docs: correct ./configure line in tracing.txtJun Koi
This patch corrects the configure's trace option in docs/tracing.txt. Signed-off-by: Jun Koi <junkoi2004@gmail.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-03-12trace: make trace_thread_create() use its function argJun Koi
This patch makes trace_thread_create() to use its function arg to initialize thread. The other choice is to make this a function to use void arg, but i prefer this way. Signed-off-by: Jun Koi <junkoi2004@gmail.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
2012-03-12tracetool: Omit useless QEMU_*_ENABLED() checkStefan Hajnoczi
SystemTap provides a "semaphore" that can optionally be tested before executing a trace event. The purpose of this mechanism is to skip expensive tracing code when the trace event is disabled. For example, some applications may have trace events that format or convert strings for trace events. This expensive processing should only be done in the case where the trace event is enabled. Since QEMU's generated trace events never have such special-purpose code, there is no reason to add the semaphore check. Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>