From: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Date: Tue, 13 Feb 2024 18:22:08 -0800
Subject: x86/entry_32: Add VERW just before userspace transition
Git-commit: a0e2dab44d22b913b4c228c8b52b2a104434b0b3
Patch-mainline: v6.8-rc6
References: git-fixes
As done for entry_64, add support for executing VERW late in exit to
user path for 32-bit mode.
Cc: <stable@kernel.org>
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Acked-by: Nikolay Borisov <nik.borisov@suse.com>
---
arch/x86/entry/entry_32.S | 3 +++
1 file changed, 3 insertions(+)
--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -278,6 +278,7 @@ ENTRY(schedule_tail_wrapper)
pushl %eax
call schedule_tail
popl %eax
+ CLEAR_CPU_BUFFERS
FRAME_END
RET
@@ -565,6 +566,7 @@ restore_all:
#endif
.Lrestore_nocheck:
RESTORE_REGS 4 # skip orig_eax/error_code
+ CLEAR_CPU_BUFFERS
.Lirq_return:
INTERRUPT_RETURN
@@ -1020,6 +1022,7 @@ ENTRY(nmi)
/* Not on SYSENTER stack. */
call do_nmi
+ CLEAR_CPU_BUFFERS
jmp .Lrestore_all_notrace
.Lnmi_from_sysenter_stack: