mirror of
https://github.com/torvalds/linux.git
synced 2026-07-28 10:09:10 +02:00
Linux kernel source tree
a344e258ac
The pKVM FF-A proxy rejects FF-A requests other than FFA_VERSION until
version negotiation is complete, which is signalled by setting the
global 'has_version_negotiated' variable.
To avoid excessive locking, this variable is checked directly from
kvm_host_ffa_handler() in response to an FF-A call, but this can race
against another CPU performing the negotiation and potentially lead to
reading a torn value (incredibly unlikely for a 'bool') or problematic
re-ordering of the accesses to 'has_version_negotiated' and
'hyp_ffa_version' whereby a stale version number could be read by
__do_ffa_mem_xfer().
Use acquire/release primitives when writing 'has_version_negotiated'
with the version lock held and when reading without the lock held.
Cc: Sebastian Ene <sebastianene@google.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Quentin Perret <qperret@google.com>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Marc Zyngier <maz@kernel.org>
Fixes:
|
||
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .clippy.toml | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| 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 reStructuredText markup notation.
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.