The following commit has been merged into the x86/urgent branch of tip: Commit-ID: a67d262a840e0cc2daf4b55940f4a318b831d911 Gitweb: https://git.kernel.org/tip/a67d262a840e0cc2daf4b55940f4a318b831d911 Author: Pawan Gupta <pawan.kumar.gupta@xxxxxxxxxxxxxxx> AuthorDate: Sun, 04 Feb 2024 23:19:33 -08:00 Committer: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> CommitterDate: Mon, 12 Feb 2024 10:25:22 -08:00 x86/entry_32: Add VERW just before userspace transition As done for entry_64, add support for executing VERW late in exit to user path for 32-bit mode. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@xxxxxxxxxxxxxxx> Signed-off-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/all/20240204-delay-verw-v7-3-59be2d704cb2%40linux.intel.com --- arch/x86/entry/entry_32.S | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/entry/entry_32.S b/arch/x86/entry/entry_32.S index c73047b..fba4276 100644 --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -885,6 +885,7 @@ SYM_FUNC_START(entry_SYSENTER_32) BUG_IF_WRONG_CR3 no_user_check=1 popfl popl %eax + CLEAR_CPU_BUFFERS /* * Return back to the vDSO, which will pop ecx and edx. @@ -954,6 +955,7 @@ restore_all_switch_stack: /* Restore user state */ RESTORE_REGS pop=4 # skip orig_eax/error_code + CLEAR_CPU_BUFFERS .Lirq_return: /* * ARCH_HAS_MEMBARRIER_SYNC_CORE rely on IRET core serialization @@ -1146,6 +1148,7 @@ SYM_CODE_START(asm_exc_nmi) /* Not on SYSENTER stack. */ call exc_nmi + CLEAR_CPU_BUFFERS jmp .Lnmi_return .Lnmi_from_sysenter_stack: