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Subject[RFC][PATCH 5/7] x86/debug: Remove handle_debug(.user) argument

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
arch/x86/kernel/traps.c | 21 ++++++++++-----------
1 file changed, 10 insertions(+), 11 deletions(-)

--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -783,25 +783,18 @@ static __always_inline unsigned long deb
*
* May run on IST stack.
*/
-static void handle_debug(struct pt_regs *regs, unsigned long dr6, bool user)
+static void handle_debug(struct pt_regs *regs, unsigned long dr6)
{
struct task_struct *tsk = current;
bool user_icebp;
int si_code;

/*
- * If DR6 is zero, no point in trying to handle it. The kernel is
- * not using INT1.
- */
- if (!user && !dr6)
- return;
-
- /*
* 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 = user && !dr6;
+ user_icebp = !dr6;

/* Store the virtualized DR6 value */
tsk->thread.debugreg6 = dr6;
@@ -874,7 +867,13 @@ static __always_inline void exc_debug_ke
regs->flags &= ~X86_EFLAGS_TF;
}

- handle_debug(regs, dr6, false);
+ /*
+ * The kernel doesn't use INT1
+ */
+ if (!dr6)
+ goto out;
+
+ handle_debug(regs, dr6);

out:
instrumentation_end();
@@ -904,7 +903,7 @@ static __always_inline void exc_debug_us
irqentry_enter_from_user_mode(regs);
instrumentation_begin();

- handle_debug(regs, dr6, true);
+ handle_debug(regs, dr6);

instrumentation_end();
irqentry_exit_to_user_mode(regs);

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