[xen stable-4.18] x86/spec: do not print thunk option selection if not built-in

[patchbot@xxxxxxx]

commit 7404c25efdc70091817479b80dbbd945e6ab4861
Author:     Roger Pau Monné <roger.pau@xxxxxxxxxx>
AuthorDate: Tue Mar 5 11:51:56 2024 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Tue Mar 5 11:51:56 2024 +0100

    x86/spec: do not print thunk option selection if not built-in
    
    Since the thunk built-in enable is printed as part of the "Compiled-in
    support:" line, avoid printing anything in "Xen settings:" if the thunk is
    disabled at build time.
    
    Note the BTI-Thunk option printing is also adjusted to print a colon in the
    same way the other options on the line do.
    
    Requested-by: Jan Beulich <jbeulich@xxxxxxxx>
    Signed-off-by: Roger Pau Monné <roger.pau@xxxxxxxxxx>
    Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
    master commit: 576528a2a742069af203e90c613c5c93e23c9755
    master date: 2024-02-27 14:58:40 +0100
---
 xen/arch/x86/spec_ctrl.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/xen/arch/x86/spec_ctrl.c b/xen/arch/x86/spec_ctrl.c
index 99ecfb3cba..a965b6db28 100644
--- a/xen/arch/x86/spec_ctrl.c
+++ b/xen/arch/x86/spec_ctrl.c
@@ -504,11 +504,12 @@ static void __init print_details(enum ind_thunk thunk)
                "\n");
 
     /* Settings for Xen's protection, irrespective of guests. */
-    printk("  Xen settings: BTI-Thunk %s, SPEC_CTRL: %s%s%s%s%s, 
Other:%s%s%s%s%s%s\n",
-           thunk == THUNK_NONE      ? "N/A" :
-           thunk == THUNK_RETPOLINE ? "RETPOLINE" :
-           thunk == THUNK_LFENCE    ? "LFENCE" :
-           thunk == THUNK_JMP       ? "JMP" : "?",
+    printk("  Xen settings: %s%sSPEC_CTRL: %s%s%s%s%s, Other:%s%s%s%s%s%s\n",
+           thunk != THUNK_NONE      ? "BTI-Thunk: " : "",
+           thunk == THUNK_NONE      ? "" :
+           thunk == THUNK_RETPOLINE ? "RETPOLINE, " :
+           thunk == THUNK_LFENCE    ? "LFENCE, " :
+           thunk == THUNK_JMP       ? "JMP, " : "?, ",
            (!boot_cpu_has(X86_FEATURE_IBRSB) &&
             !boot_cpu_has(X86_FEATURE_IBRS))         ? "No" :
            (default_xen_spec_ctrl & SPEC_CTRL_IBRS)  ? "IBRS+" :  "IBRS-",
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.18