From: Pawan Gupta pawan.kumar.gupta@linux.intel.com
commit f52ea6c26953fed339aa4eae717ee5c2133c7ff2 upstream
Processor MMIO Stale Data mitigation uses similar mitigation as MDS and TAA. In preparation for adding its mitigation, add a common function to update all mitigations that depend on MD_CLEAR.
[ bp: Add a newline in md_clear_update_mitigation() to separate statements better. ]
Signed-off-by: Pawan Gupta pawan.kumar.gupta@linux.intel.com Signed-off-by: Borislav Petkov bp@suse.de Signed-off-by: Thomas Gleixner tglx@linutronix.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/kernel/cpu/bugs.c | 59 +++++++++++++++++++++++++-------------------- 1 file changed, 33 insertions(+), 26 deletions(-)
--- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -41,7 +41,7 @@ static void __init spectre_v2_select_mit static void __init ssb_select_mitigation(void); static void __init l1tf_select_mitigation(void); static void __init mds_select_mitigation(void); -static void __init mds_print_mitigation(void); +static void __init md_clear_update_mitigation(void); static void __init taa_select_mitigation(void); static void __init srbds_select_mitigation(void); static void __init l1d_flush_select_mitigation(void); @@ -123,10 +123,10 @@ void __init check_bugs(void) l1d_flush_select_mitigation();
/* - * As MDS and TAA mitigations are inter-related, print MDS - * mitigation until after TAA mitigation selection is done. + * As MDS and TAA mitigations are inter-related, update and print their + * mitigation after TAA mitigation selection is done. */ - mds_print_mitigation(); + md_clear_update_mitigation();
arch_smt_update();
@@ -267,14 +267,6 @@ static void __init mds_select_mitigation } }
-static void __init mds_print_mitigation(void) -{ - if (!boot_cpu_has_bug(X86_BUG_MDS) || cpu_mitigations_off()) - return; - - pr_info("%s\n", mds_strings[mds_mitigation]); -} - static int __init mds_cmdline(char *str) { if (!boot_cpu_has_bug(X86_BUG_MDS)) @@ -329,7 +321,7 @@ static void __init taa_select_mitigation /* TSX previously disabled by tsx=off */ if (!boot_cpu_has(X86_FEATURE_RTM)) { taa_mitigation = TAA_MITIGATION_TSX_DISABLED; - goto out; + return; }
if (cpu_mitigations_off()) { @@ -343,7 +335,7 @@ static void __init taa_select_mitigation */ if (taa_mitigation == TAA_MITIGATION_OFF && mds_mitigation == MDS_MITIGATION_OFF) - goto out; + return;
if (boot_cpu_has(X86_FEATURE_MD_CLEAR)) taa_mitigation = TAA_MITIGATION_VERW; @@ -375,18 +367,6 @@ static void __init taa_select_mitigation
if (taa_nosmt || cpu_mitigations_auto_nosmt()) cpu_smt_disable(false); - - /* - * Update MDS mitigation, if necessary, as the mds_user_clear is - * now enabled for TAA mitigation. - */ - if (mds_mitigation == MDS_MITIGATION_OFF && - boot_cpu_has_bug(X86_BUG_MDS)) { - mds_mitigation = MDS_MITIGATION_FULL; - mds_select_mitigation(); - } -out: - pr_info("%s\n", taa_strings[taa_mitigation]); }
static int __init tsx_async_abort_parse_cmdline(char *str) @@ -411,6 +391,33 @@ static int __init tsx_async_abort_parse_ early_param("tsx_async_abort", tsx_async_abort_parse_cmdline);
#undef pr_fmt +#define pr_fmt(fmt) "" fmt + +static void __init md_clear_update_mitigation(void) +{ + if (cpu_mitigations_off()) + return; + + if (!static_key_enabled(&mds_user_clear)) + goto out; + + /* + * mds_user_clear is now enabled. Update MDS mitigation, if + * necessary. + */ + if (mds_mitigation == MDS_MITIGATION_OFF && + boot_cpu_has_bug(X86_BUG_MDS)) { + mds_mitigation = MDS_MITIGATION_FULL; + mds_select_mitigation(); + } +out: + if (boot_cpu_has_bug(X86_BUG_MDS)) + pr_info("MDS: %s\n", mds_strings[mds_mitigation]); + if (boot_cpu_has_bug(X86_BUG_TAA)) + pr_info("TAA: %s\n", taa_strings[taa_mitigation]); +} + +#undef pr_fmt #define pr_fmt(fmt) "SRBDS: " fmt
enum srbds_mitigations {