Linux mainline fork with MSM8998 patches | https://mainline.space | Currently supported devices:
OnePlus 5/5T, Xiaomi Mi 6, F(x)tec Pro¹ (2019 QX1000 model) & Sony Xperia XZ Premium (UNTESTED!)
33a3164161
Prevent the TDP MMU from yielding when zapping a gfn range during NX page recovery. If a flush is pending from a previous invocation of the zapping helper, either in the TDP MMU or the legacy MMU, but the TDP MMU has not accumulated a flush for the current invocation, then yielding will release mmu_lock with stale TLB entries. That being said, this isn't technically a bug fix in the current code, as the TDP MMU will never yield in this case. tdp_mmu_iter_cond_resched() will yield if and only if it has made forward progress, as defined by the current gfn vs. the last yielded (or starting) gfn. Because zapping a single shadow page is guaranteed to (a) find that page and (b) step sideways at the level of the shadow page, the TDP iter will break its loop before getting a chance to yield. But that is all very, very subtle, and will break at the slightest sneeze, e.g. zapping while holding mmu_lock for read would break as the TDP MMU wouldn't be guaranteed to see the present shadow page, and thus could step sideways at a lower level. Cc: Ben Gardon <bgardon@google.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Message-Id: <20210325200119.1359384-4-seanjc@google.com> [Add lockdep assertion. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| 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 Restructured Text 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.