Minimal supplement to upstream Kernel Self Protection Project changes. Features already provided by SELinux + Yama and archs other than multiarch arm64 / x86_64 aren't in scope. Only tags have stable history. Shared IRC channel with KSPP: irc.libera.chat #linux-hardening
High latencies can be observed caused by a daemon periodically reading various MSR on all cpus. On KASAN enabled kernels ~10ms latencies can be observed simply reading one MSR. Even without KASAN, sending an IPI to a CPU, which is in a deep sleep state or in a long hard IRQ disabled section, waiting for the answer can consume hundreds of microseconds. All usage sites are in preemptible context, convert rdmsr_safe_on_cpu() to use a completion instead of busy polling. Overall daemon cpu usage was reduced by 35 %, and latencies caused by msr_read() disappeared. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Eric Dumazet <eric.dumazet@gmail.com> Link: https://lkml.kernel.org/r/20180323215818.127774-1-edumazet@google.com |
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arch | ||
block | ||
certs | ||
crypto | ||
Documentation | ||
drivers | ||
firmware | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
LICENSES | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. 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.