From: Mark Brown <broonie@kernel.org> In order to use FEAT_NMI we must be able to use ALLINT, require that it behave as though not trapped when it is present. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Jie Liu <liujie375@h-partners.com> --- Documentation/arm64/booting.rst | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/Documentation/arm64/booting.rst b/Documentation/arm64/booting.rst index d3f3a60fbf25..eca3e4d1d18d 100644 --- a/Documentation/arm64/booting.rst +++ b/Documentation/arm64/booting.rst @@ -245,6 +245,12 @@ Before jumping into the kernel, the following conditions must be met: - HCR_EL2.APK (bit 40) must be initialised to 0b1 - HCR_EL2.API (bit 41) must be initialised to 0b1 + For CPUs with Non-maskable Interrupts (FEAT_NMI): + + - If the kernel is entered at EL1 and EL2 is present: + + - HCRX_EL2.TALLINT must be initialised to 0b0. + The requirements described above for CPU mode, caches, MMUs, architected timers, coherency and system registers apply to all CPUs. All CPUs must enter the kernel in the same exception level. -- 2.25.1