[PATCH 10/13] x86/debug: Remove aout_dump_debugregs()

From: Peter Zijlstra
Date: Wed Sep 02 2020 - 09:55:53 EST


Unused remnants for the bit-bucket.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
arch/x86/include/asm/debugreg.h | 2 --
arch/x86/kernel/hw_breakpoint.c | 36 ------------------------------------
2 files changed, 38 deletions(-)

--- a/arch/x86/include/asm/debugreg.h
+++ b/arch/x86/include/asm/debugreg.h
@@ -90,8 +90,6 @@ static __always_inline bool hw_breakpoin
return __this_cpu_read(cpu_dr7) & DR_GLOBAL_ENABLE_MASK;
}

-extern void aout_dump_debugregs(struct user *dump);
-
extern void hw_breakpoint_restore(void);

static __always_inline unsigned long local_db_save(void)
--- a/arch/x86/kernel/hw_breakpoint.c
+++ b/arch/x86/kernel/hw_breakpoint.c
@@ -442,42 +442,6 @@ int hw_breakpoint_arch_parse(struct perf
}

/*
- * Dump the debug register contents to the user.
- * We can't dump our per cpu values because it
- * may contain cpu wide breakpoint, something that
- * doesn't belong to the current task.
- *
- * TODO: include non-ptrace user breakpoints (perf)
- */
-void aout_dump_debugregs(struct user *dump)
-{
- int i;
- int dr7 = 0;
- struct perf_event *bp;
- struct arch_hw_breakpoint *info;
- struct thread_struct *thread = &current->thread;
-
- for (i = 0; i < HBP_NUM; i++) {
- bp = thread->ptrace_bps[i];
-
- if (bp && !bp->attr.disabled) {
- dump->u_debugreg[i] = bp->attr.bp_addr;
- info = counter_arch_bp(bp);
- dr7 |= encode_dr7(i, info->len, info->type);
- } else {
- dump->u_debugreg[i] = 0;
- }
- }
-
- dump->u_debugreg[4] = 0;
- dump->u_debugreg[5] = 0;
- dump->u_debugreg[6] = current->thread.debugreg6;
-
- dump->u_debugreg[7] = dr7;
-}
-EXPORT_SYMBOL_GPL(aout_dump_debugregs);
-
-/*
* Release the user breakpoints used by ptrace
*/
void flush_ptrace_hw_breakpoint(struct task_struct *tsk)