diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/entry/entry_64_compat.S | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S index c779046cc3..2e8ead6090 100644 --- a/arch/x86/entry/entry_64_compat.S +++ b/arch/x86/entry/entry_64_compat.S @@ -90,10 +90,6 @@ SYM_INNER_LABEL(entry_SYSENTER_compat_after_hwframe, SYM_L_GLOBAL) cld - IBRS_ENTER - UNTRAIN_RET - CLEAR_BRANCH_HISTORY - /* * SYSENTER doesn't filter flags, so we need to clear NT and AC * ourselves. To save a few cycles, we can check whether @@ -117,6 +113,16 @@ SYM_INNER_LABEL(entry_SYSENTER_compat_after_hwframe, SYM_L_GLOBAL) jnz .Lsysenter_fix_flags .Lsysenter_flags_fixed: + /* + * CPU bugs mitigations mechanisms can call other functions. They + * should be invoked after making sure TF is cleared because + * single-step is ignored only for instructions inside the + * entry_SYSENTER_compat function. + */ + IBRS_ENTER + UNTRAIN_RET + CLEAR_BRANCH_HISTORY + movq %rsp, %rdi call do_SYSENTER_32 jmp sysret32_from_system_call |