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2015-03-26migration: remove last_sent_block from save_page_headerJuan Quintela
Compression code (still not on tree) want to call this funtion from outside the migration thread, so we can't write to last_sent_block. Instead of reverting full patch: [PULL 07/11] save_block_hdr: we can recalculate Just revert the parts that touch last_sent_block. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2015-03-17arch_init: Count the total number of pages by using helper functionzhanghailiang
There is already a helper function ram_bytes_total(), we can use it to help counting the total number of pages used by ram blocks. Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-03-16rename save_block_hdr to save_page_headerJuan Quintela
It has always been a page header, not a block header. Once there, the flag argument was only passed to make a bit or with it, just do the or on the caller. Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-03-16save_block_hdr: we can recalculate the cont parameter hereJuan Quintela
No need to pass it through all the callers. Once there, update last_sent_block here. Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-03-16save_xbzrle_page: change calling conventionJuan Quintela
Add a parameter to pass the number of bytes written, and make it return the number of pages written instead. Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-03-16ram_save_page: change calling coventionJuan Quintela
Add a parameter to pass the number of bytes written, and make it return the number of pages written instead. Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-03-16ram_find_and_save_block: change calling conventionJuan Quintela
Add a parameter to pass the number of bytes written, and make it return the number of pages written instead. Signed-off-by: Juan Quintela <quintela@redhat.com>
2015-03-16ram: make all save_page functions take a uint64_t parameterJuan Quintela
It used to be an int, but then we can't pass directly the bytes_transferred parameter, that would happen later in the series. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Amit Shah <amit.shah@redhat.com>
2015-02-26Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2015-02-18' ↵Peter Maydell
into staging Clean up around error_get_pretty(), qerror_report_err() # gpg: Signature made Wed Feb 18 10:10:07 2015 GMT using RSA key ID EB918653 # gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" # gpg: aka "Markus Armbruster <armbru@pond.sub.org>" * remotes/armbru/tags/pull-error-2015-02-18: qemu-char: Avoid qerror_report_err() outside QMP command handlers qemu-img: Avoid qerror_report_err() outside QMP command handlers vl: Avoid qerror_report_err() outside QMP command handlers tpm: Avoid qerror_report_err() outside QMP command handlers numa: Avoid qerror_report_err() outside QMP command handlers net: Avoid qerror_report_err() outside QMP command handlers monitor: Avoid qerror_report_err() outside QMP command handlers monitor: Clean up around monitor_handle_fd_param() error: Use error_report_err() where appropriate error: New convenience function error_report_err() vhost-scsi: Improve error reporting for invalid vhostfd Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2015-02-18error: Use error_report_err() where appropriateMarkus Armbruster
Coccinelle semantic patch: @@ expression E; @@ - error_report("%s", error_get_pretty(E)); - error_free(E); + error_report_err(E); @@ expression E, S; @@ - error_report("%s", error_get_pretty(E)); + error_report_err(E); ( exit(S); | abort(); ) Trivial manual touch-ups in block/sheepdog.c. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2015-02-16Convert ram_list to RCUMike Day
Allow "unlocked" reads of the ram_list by using an RCU-enabled QLIST. The ramlist mutex is kept. call_rcu callbacks are run with the iothread lock taken, but that may change in the future. Writers still take the ramlist mutex, but they no longer need to assume that the iothread lock is taken. Readers of the list, instead, no longer require either the iothread or ramlist mutex, but they need to use rcu_read_lock() and rcu_read_unlock(). One place in arch_init.c was downgrading from write side to read side like this: qemu_mutex_lock_iothread() qemu_mutex_lock_ramlist() ... qemu_mutex_unlock_iothread() ... qemu_mutex_unlock_ramlist() and the equivalent idiom is: qemu_mutex_lock_ramlist() rcu_read_lock() ... qemu_mutex_unlock_ramlist() ... rcu_read_unlock() Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Mike Day <ncmike@ncultra.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-16exec: convert ram_list to QLISTMike Day
QLIST has RCU-friendly primitives, so switch to it. Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Mike Day <ncmike@ncultra.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-16cosmetic changes preparing for the following patchesMike Day
Reviewed-by: Fam Zheng <famz@redhat.com> Signed-off-by: Mike Day <ncmike@ncultra.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-15xbzrle: optimize XBZRLE to decrease the cache missesChenLiang
Avoid hot pages being replaced by others to remarkably decrease cache misses Sample results with the test program which quote from xbzrle.txt ran in vm:(migrate bandwidth:1GE and xbzrle cache size 8MB) the test program: include <stdlib.h> include <stdio.h> int main() { char *buf = (char *) calloc(4096, 4096); while (1) { int i; for (i = 0; i < 4096 * 4; i++) { buf[i * 4096 / 4]++; } printf("."); } } before this patch: virsh qemu-monitor-command test_vm '{"execute": "query-migrate"}' {"return":{"expected-downtime":1020,"xbzrle-cache":{"bytes":1108284, "cache-size":8388608,"cache-miss-rate":0.987013,"pages":18297,"overflow":8, "cache-miss":1228737},"status":"active","setup-time":10,"total-time":52398, "ram":{"total":12466991104,"remaining":1695744,"mbps":935.559472, "transferred":5780760580,"dirty-sync-counter":271,"duplicate":2878530, "dirty-pages-rate":29130,"skipped":0,"normal-bytes":5748592640, "normal":1403465}},"id":"libvirt-706"} 18k pages sent compressed in 52 seconds. cache-miss-rate is 98.7%, totally miss. after optimizing: virsh qemu-monitor-command test_vm '{"execute": "query-migrate"}' {"return":{"expected-downtime":2054,"xbzrle-cache":{"bytes":5066763, "cache-size":8388608,"cache-miss-rate":0.485924,"pages":194823,"overflow":0, "cache-miss":210653},"status":"active","setup-time":11,"total-time":18729, "ram":{"total":12466991104,"remaining":3895296,"mbps":937.663549, "transferred":1615042219,"dirty-sync-counter":98,"duplicate":2869840, "dirty-pages-rate":58781,"skipped":0,"normal-bytes":1588404224, "normal":387794}},"id":"libvirt-266"} 194k pages sent compressed in 18 seconds. The value of cache-miss-rate decrease to 48.59%. Signed-off-by: ChenLiang <chenliang88@huawei.com> Signed-off-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com>
2015-01-08arch_init: support resizing on incoming migrationMichael S. Tsirkin
If block used_length does not match, try to resize it. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-08exec: split length -> used_length/max_lengthMichael S. Tsirkin
This patch allows us to distinguish between two length values for each block: max_length - length of memory block that was allocated used_length - length of block used by QEMU/guest Currently, we set used_length - max_length, unconditionally. Follow-up patches allow used_length <= max_length. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
2014-11-20migration: static variables will not be reset at second migrationChenLiang
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>
2014-11-18migration: fix parameter validation on ram loadMichael S. Tsirkin
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>
2014-10-14migration: catch unknown flag combinations in ram_loadPeter Lieven
this patch extends commit db80fac by not only checking for unknown flags, but also filtering out unknown flag combinations. Suggested-by: Eric Blake <eblake@redhat.com> Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-10-04accel: Remove tcg_available() functionEduardo Habkost
As the function always return 1, it is not needed anymore. Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-01target-tricore: Add target stubs and qom-cpuBastian Koppelmann
Add TriCore target stubs, and QOM cpu, and Maintainer Signed-off-by: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Message-id: 1409572800-4116-2-git-send-email-kbastian@mail.uni-paderborn.de Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-08-09Show length mismatch error is hexAlex Bligh
When live migrate fails due to a section length mismatch we currently see an error message like: Length mismatch: 0000:00:03.0/virtio-net-pci.rom: 10000 in != 20000 The section lengths are in fact in hex, so this should read Length mismatch: 0000:00:03.0/virtio-net-pci.rom: 0x10000 in != 0x20000 Correct the error string to reflect this. Signed-off-by: Alex Bligh <alex@alex.org.uk> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-06-16migration: catch unknown flags in ram_loadPeter Lieven
if a saved vm has unknown flags in the memory data qemu currently simply ignores this flag and continues which yields in an unpredictable result. This patch catches all unknown flags and aborts the loading of the vm. Additionally error reports are thrown if the migration aborts abnormally. Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-06-10migration: Plug memory leak in migrate-set-cache-size commandChen Gang
We call g_free() after cache_fini() in migration_end(), but we don't call it after cache_fini() in xbzrle_cache_resize(), leaking the memory. cache_init() and cache_fini() are a pair. Since cache_init() allocates the cache, let cache_fini() free it. This plugs the leak. Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-05-24arch_init: replace fprintf(stderr, ...) with error_report()Le Tan
Replace fprintf(stderr,...) with error_report() in the file arch_init.c. The trailing "\n"s of the @fmt argument have been removed because @fmt of error_report() should not contain newline. Signed-off-by: Le Tan <tamlokveer@gmail.com> Reviewed-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-05-14Split ram_save_blockDr. David Alan Gilbert
ram_save_block is getting a bit too complicated, and does two separate things: 1) Finds a page to send 2) Sends the page (dealing with compression etc) Split into 'ram_save_page' to send the page and deal with compression (2) Rename remaining function to 'ram_find_and_save_block' Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-14arch_init: Simplify code for load_xbzrle()Chen Gang
For xbzrle_decode_buffer(), when decoding contents will exceed writing buffer, it will return -1, so need not check the return value whether large than writing buffer. And when failure occurs within load_xbzrle(), it always return -1 without any resources which need release. So can remove the related checking statements, and also can remove 'rc' and 'ret' local variables, Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-07arch_init: Be sure of only one exit entry with DPRINTF() for ram_load()Chen Gang
When DPRINTF() has effect, the original author wants to print all ram_load() calling results. So need use 'goto' instead of 'return' within ram_load(), just like other areas have done. Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-05-05migration: expose xbzrle cache miss rateChenLiang
expose xbzrle cache miss rate Signed-off-by: ChenLiang <chenliang88@huawei.com> Signed-off-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05migration: expose the bitmap_sync_count to the endChenLiang
expose the count that logs the times of updating the dirty bitmap to end user. Signed-off-by: ChenLiang <chenliang88@huawei.com> Signed-off-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05migration: Add counts of updating the dirty bitmapChenLiang
Add counts to log the times of updating the dirty bitmap. Signed-off-by: ChenLiang <chenliang88@huawei.com> Signed-off-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05XBZRLE: Fix one XBZRLE corruption issuesChenLiang
The page may not be inserted into cache after executing save_xbzrle_page. In case of failure to insert, the original page should be sent rather than the page in the cache. Signed-off-by: ChenLiang <chenliang88@huawei.com> Signed-off-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05migration: remove duplicate codeChenLiang
version_id is checked twice in the ram_load. Signed-off-by: ChenLiang <chenliang88@huawei.com> Signed-off-by: Gonglei <arei.gonglei@huawei.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05Init the XBZRLE.lock in ram_mig_initDr. David Alan Gilbert
Initialising the XBZRLE.lock earlier simplifies the lock use. Based on Markus's patch in: http://lists.gnu.org/archive/html/qemu-devel/2014-03/msg03879.html Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05Provide init function for ram migrationDr. David Alan Gilbert
Provide ram_mig_init (like blk_mig_init) for vl.c to initialise stuff to do with ram migration (currently in arch_init.c). Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-05-05Count used RAMBlock pages for migration_dirty_pagesDr. David Alan Gilbert
This is a fix for a bug* triggered by a migration after hot unplugging a few virtio-net NICs, that caused migration never to converge, because 'migration_dirty_pages' is incorrectly initialised. 'migration_dirty_pages' is used as a tally of the number of outstanding dirty pages, to give the migration code an idea of how much more data will need to be transferred, and thus whether it can end the iterative phase. It was initialised to the total size of the RAMBlock address space, however hotunplug can leave this space sparse, and hence migration_dirty_pages ended up too large. Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> (* https://bugzilla.redhat.com/show_bug.cgi?id=1074913 ) Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-03-08XBZRLE: Fix qemu crash when resize the xbzrle cacheGonglei
Resizing the xbzrle cache during migration causes qemu-crash, because the main-thread and migration-thread modify the xbzrle cache size concurrently without lock-protection. 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: Juan Quintela <quintela@redhat.com>
2014-02-25Fix two XBZRLE corruption issuesDr. David Alan Gilbert
Push zero'd pages into the XBZRLE cache A page that was cached by XBZRLE, zero'd and then XBZRLE'd again was being compared against a stale cache value Don't use 'qemu_put_buffer_async' to put pages from the XBZRLE cache Since the cache might change before the data hits the wire Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-02-04Don't abort on memory allocation errorOrit Wasserman
It is better to fail migration in case of failure to allocate new cache item Signed-off-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-02-04Don't abort on out of memory when creating page cacheOrit Wasserman
Signed-off-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-02-04migration:fix free XBZRLE decoded_buf wrongGonglei (Arei)
When qemu do live migration with xbzrle, qemu malloc decoded_buf at destination end but free it at source end. It will crash qemu by double free error in some scenarios. Splitting the XBZRLE structure for clear logic distinguishing src/dst side. Signed-off-by: ChenLiang <chenliang88@huawei.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Orit Wasserman <owasserm@redhat.com> Signed-off-by: GongLei <arei.gonglei@huawei.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-02-04Add check for cache size smaller than page sizeOrit Wasserman
Signed-off-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-02-04Set xbzrle buffers to NULL after freeing them to avoid double free errorsOrit Wasserman
Signed-off-by: Orit Wasserman <owasserm@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com>
2014-01-13migration: synchronize memory bitmap 64bits at a timeJuan Quintela
We use the old code if the bitmaps are not aligned Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Orit Wasserman <owasserm@redhat.com>
2014-01-13ram: split function that synchronizes a rangeJuan Quintela
This function is the only bit where we care about speed. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Orit Wasserman <owasserm@redhat.com>
2014-01-13memory: unfold memory_region_test_and_clear()Juan Quintela
We are going to update the bitmap directly Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Orit Wasserman <owasserm@redhat.com>
2013-11-19migration: drop MADVISE_DONT_NEED for incoming zero pagesPeter Lieven
The madvise for zeroed out pages was introduced when every transferred zero page was memset to zero and thus allocated. Since commit 211ea740 we check for zeroness of a target page before we memset it to zero. Additionally we memmap target memory so it is essentially zero initialized (except for e.g. option roms and bios which are loaded into target memory although they shouldn't). It was reported recently that this madvise causes a performance degradation in some situations. As the madvise should only be called rarely and if it's called it is likely on a busy page (it was non-zero and changed to zero during migration) drop it completely. Reported-By: Zhang Haoyu <haoyu.zhang@huawei.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Juan Quintela <quintela@redhat.com>
2013-09-30Merge remote-tracking branch 'mst/tags/for_anthony' into stagingAnthony Liguori
pc,pci,virtio fixes and cleanups This includes pc and pci cleanups and enhancements, and a virtio-net bugfix related to softmac programming. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> # gpg: Signature made Sun 29 Sep 2013 01:51:16 AM CDT using RSA key ID D28D5469 # gpg: Can't check signature: public key not found # By Michael S. Tsirkin (8) and others # Via Michael S. Tsirkin * mst/tags/for_anthony: smbios: Factor out smbios_maybe_add_str() smbios: Make multiple -smbios type= accumulate sanely smbios: Improve diagnostics for conflicting entries smbios: Convert to QemuOpts smbios: Normalize smbios_entry_add()'s error handling to exit(1) virtio-net: fix up HMP NIC info string on reset pci: remove explicit check to 64K ioport size piix4: disable io on reset piix: use 64 bit window programmed by guest q35: use 64 bit window programmed by guest pci: add helper to retrieve the 64-bit range range: add min/max operations on ranges range: add Range to typedefs q35: make pci window address/size match guest cfg Message-id: 1380437951-21788-1-git-send-email-mst@redhat.com
2013-09-28smbios: Make multiple -smbios type= accumulate sanelyMarkus Armbruster
Currently, -smbios type=T,NAME=VAL,... adds one field (T,NAME) with value VAL to fw_cfg for each unique NAME. If NAME occurs multiple times, the last one's VAL is used (before the QemuOpts conversion, the first one was used). Multiple -smbios can add multiple fields with the same (T, NAME). SeaBIOS reads all of them from fw_cfg, but uses only the first field (T, NAME). The others are ignored. "First one wins, subsequent ones get ignored silently" isn't nice. We commonly let the last option win. Useful, because it lets you -readconfig first, then selectively override with command line options. Clean up -smbios to work the common way. Accumulate the settings, with later ones overwriting earlier ones. Put the result into fw_cfg (no more useless duplicates). Bonus cleanup: qemu_uuid_parse() no longer sets SMBIOS system uuid by side effect. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2013-09-28smbios: Convert to QemuOptsMarkus Armbruster
So that it can be set in config file for -readconfig. This tightens parsing of -smbios, and makes it more consistent with other options: unknown parameters are rejected, numbers with trailing junk are rejected, when a parameter is given multiple times, last rather than first wins, ... MST: drop one chunk to fix build errors Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>