4.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Diana Craciun <[email protected]> commit cf175dc315f90185128fb061dc05b6fbb211aa2f upstream. The speculation barrier can be disabled from the command line with the parameter: "nospectre_v1". Signed-off-by: Diana Craciun <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/powerpc/kernel/security.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) --- a/arch/powerpc/kernel/security.c +++ b/arch/powerpc/kernel/security.c @@ -16,6 +16,7 @@ unsigned long powerpc_security_features __read_mostly = SEC_FTR_DEFAULT; bool barrier_nospec_enabled; +static bool no_nospec; static void enable_barrier_nospec(bool enable) { @@ -42,9 +43,18 @@ void setup_barrier_nospec(void) enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && security_ftr_enabled(SEC_FTR_BNDS_CHK_SPEC_BAR); - enable_barrier_nospec(enable); + if (!no_nospec) + enable_barrier_nospec(enable); } +static int __init handle_nospectre_v1(char *p) +{ + no_nospec = true; + + return 0; +} +early_param("nospectre_v1", handle_nospectre_v1); + #ifdef CONFIG_DEBUG_FS static int barrier_nospec_set(void *data, u64 val) {
