Go to file
Juergen Gross 3941552aec xen: remove size limit of privcmd-buf mapping interface
Currently the size of hypercall buffers allocated via
/dev/xen/hypercall is limited to a default of 64 memory pages. For live
migration of guests this might be too small as the page dirty bitmask
needs to be sized according to the size of the guest. This means
migrating a 8GB sized guest is already exhausting the default buffer
size for the dirty bitmap.

There is no sensible way to set a sane limit, so just remove it
completely. The device node's usage is limited to root anyway, so there
is no additional DOS scenario added by allowing unlimited buffers.

While at it make the error path for the -ENOMEM case a little bit
cleaner by setting n_pages to the number of successfully allocated
pages instead of the target size.

Fixes: c51b3c639e ("xen: add new hypercall buffer mapping device")
Cc: <stable@vger.kernel.org> #4.18
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2018-11-09 16:38:34 +01:00
Documentation Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-10-24 06:47:44 +01:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
arch xen: fix xen_qlock_wait() 2018-11-09 16:37:27 +01:00
block for-4.20/block-20181021 2018-10-22 17:46:08 +01:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto Revert "net: simplify sock_poll_wait" 2018-10-23 10:57:06 -07:00
drivers xen: remove size limit of privcmd-buf mapping interface 2018-11-09 16:38:34 +01:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-10-24 06:47:44 +01:00
include CONFIG_XEN_PV breaks xen_create_contiguous_region on ARM 2018-11-02 17:18:34 +01:00
init Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 15:00:03 +01:00
ipc ipc/shm.c: use ERR_CAST() for shm_lock() error return 2018-10-05 16:32:04 -07:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-10-24 06:47:44 +01:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-10-24 06:47:44 +01:00
mm Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 17:05:28 +01:00
net tcp: add tcp_reset_xmit_timer() helper 2018-10-23 19:42:44 -07:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-10-12 21:38:46 -07:00
scripts Merge branch 'parisc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux 2018-10-23 20:02:03 +01:00
security Revert "uapi/linux/keyctl.h: don't use C++ reserved keyword as a struct member name" 2018-09-25 13:28:58 +02:00
sound Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 13:32:18 +01:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-10-24 06:47:44 +01:00
usr initramfs: move gen_initramfs_list.sh from scripts/ to usr/ 2018-08-22 23:21:44 +09:00
virt arm64 updates for 4.20: 2018-10-22 17:30:06 +01:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS add myself as reviewer for Xen support in Linux 2018-10-24 11:29:36 +02:00
Makefile Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-10-23 13:08:53 +01:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.