[patch part-II V2 04/13] x86/entry/64: Trace irqflags unconditionally as ON when returning to user space

Thomas Gleixner
2020-03-08T23:24:03Z

User space cannot longer disable interrupts so trace return to user space
unconditionally as IRQS_ON.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
V2: Cover 32bit as well
---
arch/x86/entry/entry_32.S | 2 +-
arch/x86/entry/entry_64.S | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)

--- a/arch/x86/entry/entry_32.S
+++ b/arch/x86/entry/entry_32.S
@@ -1088,7 +1088,7 @@ SYM_FUNC_START(entry_INT80_32)
STACKLEAK_ERASE

restore_all:
- TRACE_IRQS_IRET
+ TRACE_IRQS_ON
SWITCH_TO_ENTRY_STACK
CHECK_AND_APPLY_ESPFIX

--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S
@@ -174,7 +174,7 @@ SYM_INNER_LABEL(entry_SYSCALL_64_after_h
movq %rsp, %rsi
call do_syscall_64 /* returns with IRQs disabled */

- TRACE_IRQS_IRETQ /* we're about to change IF */
+ TRACE_IRQS_ON /* return enables interrupts */

/*
* Try to use SYSRET instead of IRET if we're returning to
@@ -619,7 +619,7 @@ SYM_CODE_START_LOCAL(common_interrupt)
.Lretint_user:
mov %rsp,%rdi
call prepare_exit_to_usermode
- TRACE_IRQS_IRETQ
+ TRACE_IRQS_ON

SYM_INNER_LABEL(swapgs_restore_regs_and_return_to_usermode, SYM_L_GLOBAL)
#ifdef CONFIG_DEBUG_ENTRY