diff options
| author | Dave Hansen <dave.hansen@linux.intel.com> | 2018-01-05 09:44:36 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-01-17 09:38:57 +0100 |
| commit | 4e6c2af2ba93ee8709695835920fc57148e4b397 (patch) | |
| tree | c583c16d86e459f5576426c7c52b7363255b6609 /Documentation/kernel-parameters.txt | |
| parent | d598347989aa8873cebfd7d7b4d29d7aba21b878 (diff) | |
x86/Documentation: Add PTI description
commit 01c9b17bf673b05bb401b76ec763e9730ccf1376 upstream.
Add some details about how PTI works, what some of the downsides
are, and how to debug it when things go wrong.
Also document the kernel parameter: 'pti/nopti'.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Moritz Lipp <moritz.lipp@iaik.tugraz.at>
Cc: Daniel Gruss <daniel.gruss@iaik.tugraz.at>
Cc: Michael Schwarz <michael.schwarz@iaik.tugraz.at>
Cc: Richard Fellner <richard.fellner@student.tugraz.at>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andi Lutomirsky <luto@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180105174436.1BC6FA2B@viggo.jf.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/kernel-parameters.txt')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 5d2676d043de..2b1d782eda6f 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2763,8 +2763,6 @@ bytes respectively. Such letter suffixes can also be entirely omitted. nojitter [IA-64] Disables jitter checking for ITC timers. - nopti [X86-64] Disable KAISER isolation of kernel from user. - no-kvmclock [X86,KVM] Disable paravirtualized KVM clock driver no-kvmapf [X86,KVM] Disable paravirtualized asynchronous page @@ -3327,11 +3325,20 @@ bytes respectively. Such letter suffixes can also be entirely omitted. pt. [PARIDE] See Documentation/blockdev/paride.txt. - pti= [X86_64] - Control KAISER user/kernel address space isolation: - on - enable - off - disable - auto - default setting + pti= [X86_64] Control Page Table Isolation of user and + kernel address spaces. Disabling this feature + removes hardening, but improves performance of + system calls and interrupts. + + on - unconditionally enable + off - unconditionally disable + auto - kernel detects whether your CPU model is + vulnerable to issues that PTI mitigates + + Not specifying this option is equivalent to pti=auto. + + nopti [X86_64] + Equivalent to pti=off pty.legacy_count= [KNL] Number of legacy pty's. Overwrites compiled-in |