@@ -50,7 +50,8 @@ static int8_t __initdata opt_psfd = -1;
int8_t __ro_after_init opt_ibpb_ctxt_switch = -1;
int8_t __read_mostly opt_eager_fpu = -1;
int8_t __read_mostly opt_l1d_flush = -1;
-static bool __initdata opt_branch_harden = true;
+static bool __initdata opt_branch_harden =
+ IS_ENABLED(CONFIG_SPECULATIVE_HARDEN_BRANCH);
bool __initdata bsp_delay_spec_ctrl;
uint8_t __read_mostly default_xen_spec_ctrl;
@@ -268,7 +269,16 @@ static int __init cf_check parse_spec_ctrl(const char *s)
else if ( (val = parse_boolean("l1d-flush", s, ss)) >= 0 )
opt_l1d_flush = val;
else if ( (val = parse_boolean("branch-harden", s, ss)) >= 0 )
- opt_branch_harden = val;
+ {
+ if ( IS_ENABLED(CONFIG_SPECULATIVE_HARDEN_BRANCH) )
+ opt_branch_harden = val;
+ else
+ {
+ no_config_param("SPECULATIVE_HARDEN_BRANCH", "spec-ctrl", s,
+ ss);
+ rc = -EINVAL;
+ }
+ }
else if ( (val = parse_boolean("srb-lock", s, ss)) >= 0 )
opt_srb_lock = val;
else if ( (val = parse_boolean("unpriv-mmio", s, ss)) >= 0 )
The current logic to handle the BRANCH_HARDEN option will report it as enabled even when build-time disabled. Fix this by only allowing the option to be set when support for it is built into Xen. Fixes: 2d6f36daa086 ('x86/nospec: Introduce CONFIG_SPECULATIVE_HARDEN_BRANCH') Signed-off-by: Roger Pau Monné <roger.pau@citrix.com> --- Changes since v2: - Use IS_ENABLED() in the parser. Changes since v1: - Use no_config_param(). --- xen/arch/x86/spec_ctrl.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)