Get rid of the two variables, avoid computing si_code when not needed
and be consistent about which dr6 value is used.
This makes it easier to shuffle code around later.
Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
---
arch/x86/kernel/traps.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -786,15 +786,6 @@ static __always_inline unsigned long deb
static void handle_debug(struct pt_regs *regs, unsigned long dr6)
{
struct task_struct *tsk = current;
- bool user_icebp;
- int si_code;
-
- /*
- * If dr6 has no reason to give us about the origin of this trap,
- * then it's very likely the result of an icebp/int01 trap.
- * User wants a sigtrap for that.
- */
- user_icebp = !dr6;
/* Store the virtualized DR6 value */
tsk->thread.debugreg6 = dr6;
@@ -813,6 +804,11 @@ static void handle_debug(struct pt_regs
goto out;
}
+ /*
+ * Reload dr6, the notifier might have changed it.
+ */
+ dr6 = tsk->thread.debugreg6;
+
if (WARN_ON_ONCE((dr6 & DR_STEP) && !user_mode(regs))) {
/*
* Historical junk that used to handle SYSENTER single-stepping.
@@ -825,9 +821,13 @@ static void handle_debug(struct pt_regs
regs->flags &= ~X86_EFLAGS_TF;
}
- si_code = get_si_code(tsk->thread.debugreg6);
- if (tsk->thread.debugreg6 & (DR_STEP | DR_TRAP_BITS) || user_icebp)
- send_sigtrap(regs, 0, si_code);
+ /*
+ * If dr6 has no reason to give us about the origin of this trap,
+ * then it's very likely the result of an icebp/int01 trap.
+ * User wants a sigtrap for that.
+ */
+ if (dr6 & (DR_STEP | DR_TRAP_BITS) || !dr6)
+ send_sigtrap(regs, 0, get_si_code(dr6));
out:
cond_local_irq_disable(regs);
