This is a note to let you know that I've just added the patch titled x86/spectre: Check CONFIG_RETPOLINE in command line parser to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: x86-spectre-check-config_retpoline-in-command-line-parser.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Thu Feb 8 03:30:27 CET 2018 From: Dou Liyang <douly.fnst@xxxxxxxxxxxxxx> Date: Tue, 30 Jan 2018 14:13:50 +0800 Subject: x86/spectre: Check CONFIG_RETPOLINE in command line parser From: Dou Liyang <douly.fnst@xxxxxxxxxxxxxx> (cherry picked from commit 9471eee9186a46893726e22ebb54cade3f9bc043) The spectre_v2 option 'auto' does not check whether CONFIG_RETPOLINE is enabled. As a consequence it fails to emit the appropriate warning and sets feature flags which have no effect at all. Add the missing IS_ENABLED() check. Fixes: da285121560e ("x86/spectre: Add boot time option to select Spectre v2 mitigation") Signed-off-by: Dou Liyang <douly.fnst@xxxxxxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: ak@xxxxxxxxxxxxxxx Cc: peterz@xxxxxxxxxxxxx Cc: Tomohiro" <misono.tomohiro@xxxxxxxxxxxxxx> Cc: dave.hansen@xxxxxxxxx Cc: bp@xxxxxxxxx Cc: arjan@xxxxxxxxxxxxxxx Cc: dwmw@xxxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Link: https://lkml.kernel.org/r/f5892721-7528-3647-08fb-f8d10e65ad87@xxxxxxxxxxxxxx Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/kernel/cpu/bugs.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -212,10 +212,10 @@ static void __init spectre_v2_select_mit return; case SPECTRE_V2_CMD_FORCE: - /* FALLTRHU */ case SPECTRE_V2_CMD_AUTO: - goto retpoline_auto; - + if (IS_ENABLED(CONFIG_RETPOLINE)) + goto retpoline_auto; + break; case SPECTRE_V2_CMD_RETPOLINE_AMD: if (IS_ENABLED(CONFIG_RETPOLINE)) goto retpoline_amd; Patches currently in stable-queue which might be from douly.fnst@xxxxxxxxxxxxxx are queue-4.9/x86-spectre-check-config_retpoline-in-command-line-parser.patch