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  1. 01 7月, 2014 1 次提交
    • C
      qemu-img create: add 'nocow' option · 4ab15590
      由 Chunyan Liu 提交于 
      Add 'nocow' option so that users could have a chance to set NOCOW flag to
newly created files. It's useful on btrfs file system to enhance performance.

Btrfs has low performance when hosting VM images, even more when the guest
in those VM are also using btrfs as file system. One way to mitigate this bad
performance is to turn off COW attributes on VM files. Generally, there are
two ways to turn off NOCOW on btrfs: a) by mounting fs with nodatacow, then
all newly created files will be NOCOW. b) per file. Add the NOCOW file
attribute. It could only be done to empty or new files.

This patch tries the second way, according to the option, it could add NOCOW
per file.

For most block drivers, since the create file step is in raw-posix.c, so we
can do setting NOCOW flag ioctl in raw-posix.c only.

But there are some exceptions, like block/vpc.c and block/vdi.c, they are
creating file by calling qemu_open directly. For them, do the same setting
NOCOW flag ioctl work in them separately.

[Fixed up 082.out due to the new 'nocow' creation option
--Stefan]
Signed-off-by: NChunyan Liu <cyliu@suse.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      4ab15590
  3. 18 4月, 2014 1 次提交
    • M
      doc: grammify "allows to" · 9d85d557
      由 Michael Tokarev 提交于 
      English language grammar does not allow usage
of the word "allows" directly followed by an
infinitive, declaring constructs like "something
allows to do somestuff" un-grammatical.  Often
it is possible to just insert "one" between "allows"
and "to" to make the construct grammatical, but
usually it is better to re-phrase the statement.

This patch tries to fix 4 examples of "allows to"
usage in qemu doc, but does not address comments
in the code with similar constructs.  It also adds
missing "the" in the same line.
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>
      9d85d557
  5. 27 3月, 2014 2 次提交
  7. 01 2月, 2014 1 次提交
    • D
      Describe flaws in qcow/qcow2 encryption in the docs · 136cd19d
      由 Daniel P. Berrange 提交于 
      The qemu-img.texi / qemu-doc.texi files currently describe the
qcow2/qcow2 encryption thus

  "Encryption uses the AES format which is very secure (128 bit
   keys). Use a long password (16 characters) to get maximum
   protection."

While AES is indeed a strong encryption system, the way that
QCow/QCow2 use it results in a poor/weak encryption system.
Due to the use of predictable IVs, based on the sector number
extended to 128 bits, it is vulnerable to chosen plaintext
attacks which can reveal the existence of encrypted data.

The direct use of the user passphrase as the encryption key
also leads to an inability to change the passphrase of an
image. If passphrase is ever compromised the image data will
all be vulnerable, since it cannot be re-encrypted. The admin
has to clone the image files with a new passphrase and then
use a program like shred to secure erase all the old files.

Recommend against any use of QCow/QCow2 encryption, directing
users to dm-crypt / LUKS which can meet modern cryptography
best practices.

[Changed "Qcow" to "qcow" for consistency.
--Stefan]
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
      136cd19d
  9. 22 1月, 2014 1 次提交
  11. 20 12月, 2013 1 次提交
  13. 29 6月, 2013 1 次提交
  15. 26 5月, 2013 1 次提交
    • B
      Remove Sun4c, Sun4d and a few CPUs · 6a4e1771
      由 Blue Swirl 提交于 
      Sun4c and Sun4d architectures and related CPUs are not fully implemented
(especially Sun4c MMU) and there has been no interest for them.

Likewise, a few CPUs (Cypress, Ross etc) are only half implemented.

Remove the machines and CPUs, they can be re-added if needed later.
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>
      6a4e1771
  17. 12 5月, 2013 1 次提交
  19. 26 4月, 2013 1 次提交
  21. 15 4月, 2013 2 次提交
  23. 04 3月, 2013 2 次提交
  25. 27 2月, 2013 1 次提交
    • P
      qemu-log: default to stderr for logging output · 989b697d
      由 Peter Maydell 提交于 
      Switch the default for qemu_log logging output from "/tmp/qemu.log"
to stderr. This is an incompatible change in some sense, but logging
is mostly used for debugging purposes so it shouldn't affect production
use. The previous behaviour can be obtained by adding "-D /tmp/qemu.log"
to the command line.

This change requires us to:
 * update all the documentation/help text (we take the opportunity
   to smooth out minor inconsistencies between the phrasing in
   linux-user/bsd-user/system help messages)
 * make linux-user and bsd-user defer to qemu-log for the default
   logging destination rather than overriding it themselves
 * ensure that all logfile closing is done via qemu_log_close()
   and that that function doesn't close stderr
as well as the obvious change to the behaviour of do_qemu_set_log()
when no logfile name has been specified.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Message-id: 1361901160-28729-1-git-send-email-peter.maydell@linaro.org
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      989b697d
  27. 30 11月, 2012 1 次提交
  29. 15 11月, 2012 1 次提交
  31. 12 11月, 2012 1 次提交
  33. 09 8月, 2012 1 次提交
    • R
      iscsi: Pick default initiator-name based on the name of the VM · 31459f46
      由 Ronnie Sahlberg 提交于 
      This patch updates the iscsi layer to automatically pick a 'unique'
initiator-name based on the name of the vm in case the user has not set
an explicit iqn-name to use.

Create a new function qemu_get_vm_name() that returns the name of the VM,
if specified.

This way we can thus create default names to use as the initiator name
based on the guest session.

If the VM is not named via the '-name' command line argument, the iscsi
initiator-name used wiull simply be

    iqn.2008-11.org.linux-kvm

If a name for the VM was specified with the '-name' option, iscsi will
use a default initiatorname of

    iqn.2008-11.org.linux-kvm:<name>

These names are just the default iscsi initiator name that qemu will
generate/use only when the user has not set an explicit initiator name
via the commandlines or config files.
Signed-off-by: NRonnie Sahlberg <ronniesahlberg@gmail.com>
      31459f46
  35. 04 8月, 2012 1 次提交
    • P
      vnc: disable VNC password authentication (security type 2) when in FIPS mode · 0f66998f
      由 Paul Moore 提交于 
      FIPS 140-2 requires disabling certain ciphers, including DES, which is used
by VNC to obscure passwords when they are sent over the network.  The
solution for FIPS users is to disable the use of VNC password auth when the
host system is operating in FIPS compliance mode and the user has specified
'-enable-fips' on the QEMU command line.

This patch causes QEMU to emit a message to stderr when the host system is
running in FIPS mode and a VNC password was specified on the commend line.
If the system is not running in FIPS mode, or is running in FIPS mode but
VNC password authentication was not requested, QEMU operates normally.
Signed-off-by: NPaul Moore <pmoore@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      0f66998f
  37. 03 8月, 2012 1 次提交
    • P
      Support 'help' as a synonym for '?' in command line options · c8057f95
      由 Peter Maydell 提交于 
      For command line options which permit '?' meaning 'please list the
permitted values', add support for 'help' as a synonym, by abstracting
the check out into a helper function.

This change means that in some cases where we were being lazy in
our string parsing, "?junk" will now be rejected as an invalid option
rather than being (undocumentedly) treated the same way as "?".

Update the documentation to use 'help' rather than '?', since '?'
is a shell metacharacter and thus prone to fail confusingly if there
is a single character filename in the current working directory and
the '?' has not been escaped. It's therefore better to steer users
towards 'help', though '?' is retained for backwards compatibility.

We do not, however, update the output of the system emulator's -help
(or any documentation autogenerated from the qemu-options.hx which
is the source of the -help text) because libvirt parses our -help
output and will break. At a later date when QEMU provides a better
interface so libvirt can avoid having to do this, we can update the
-help text too.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      c8057f95
  39. 18 7月, 2012 1 次提交
  41. 14 5月, 2012 2 次提交
  43. 01 5月, 2012 1 次提交
  45. 07 4月, 2012 2 次提交
  47. 09 2月, 2012 1 次提交
    • R
      iSCSI: add configuration variables for iSCSI · f9dadc98
      由 Ronnie Sahlberg 提交于 
      This patch adds configuration variables for iSCSI to set
initiator-name to use when logging in to the target,
which type of header-digest to negotiate with the target
and username and password for CHAP authentication.

This allows specifying a initiator-name either from the command line
-iscsi initiator-name=iqn.2004-01.com.example:test
or from a configuration file included with -readconfig
    [iscsi]
      initiator-name = iqn.2004-01.com.example:test
      header-digest = CRC32C|CRC32C-NONE|NONE-CRC32C|NONE
      user = CHAP username
      password = CHAP password

If you use several different targets, you can also configure this on a per
target basis by using a group name:
    [iscsi "iqn.target.name"]
    ...

The configuration file can be read using -readconfig.
Example :
qemu-system-i386 -drive file=iscsi://127.0.0.1/iqn.ronnie.test/1
 -readconfig iscsi.conf
Signed-off-by: NRonnie Sahlberg <ronniesahlberg@gmail.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      f9dadc98
  49. 14 12月, 2011 1 次提交
  51. 18 11月, 2011 1 次提交
  53. 17 11月, 2011 1 次提交
  55. 26 10月, 2011 1 次提交
  57. 16 10月, 2011 1 次提交
  59. 05 8月, 2011 1 次提交
  61. 15 5月, 2011 1 次提交
  63. 07 2月, 2011 1 次提交
  65. 21 1月, 2011 1 次提交
  67. 10 1月, 2011 2 次提交