From 07fd1761e1cd2b5ecdb470fc228d52ccdf75e05b Mon Sep 17 00:00:00 2001 From: Cyril Bur Date: Thu, 12 Oct 2017 21:17:16 +1100 Subject: powerpc/tm: Add commandline option to disable hardware transactional memory Currently the kernel relies on firmware to inform it whether or not the CPU supports HTM and as long as the kernel was built with CONFIG_PPC_TRANSACTIONAL_MEM=y then it will allow userspace to make use of the facility. There may be situations where it would be advantageous for the kernel to not allow userspace to use HTM, currently the only way to achieve this is to recompile the kernel with CONFIG_PPC_TRANSACTIONAL_MEM=n. This patch adds a simple commandline option so that HTM can be disabled at boot time. Signed-off-by: Cyril Bur [mpe: Simplify to a bool, move to prom.c, put doco in the right place. Always disable, regardless of initial state, to avoid user confusion.] Signed-off-by: Michael Ellerman --- Documentation/admin-guide/kernel-parameters.txt | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'Documentation') diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 05496622b4ef..ef03e6e16bdb 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3185,6 +3185,10 @@ allowed (eg kernel_enable_fpu()/kernel_disable_fpu()). There is some performance impact when enabling this. + ppc_tm= [PPC] + Format: {"off"} + Disable Hardware Transactional Memory + print-fatal-signals= [KNL] debug: print fatal signals -- cgit