[PATCH 23/41] x86/alternatives: Remove the 'addr == NULL means forced-flush' hack from text_poke_int3_finish()/text_poke_int3_flush()/tp_addr_ordered()
From: Ingo Molnar
Date: Thu Mar 27 2025 - 16:58:46 EST
There's this weird hack used by text_poke_int3_finish() to indicate
a 'forced flush':
text_poke_int3_flush(NULL);
Just open-code the vector-flush in a straightforward fashion:
text_poke_int3_batch(tp_vec, tp_vec_nr);
tp_vec_nr = 0;
And get rid of !addr hack from tp_addr_ordered().
Leave a WARN_ON_ONCE(), just in case some external code learned
to rely on this behavior.
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/kernel/alternative.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 938e8e70a379..906fb45b9e65 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -2847,12 +2847,11 @@ static bool tp_addr_ordered(void *addr)
{
struct text_poke_int3_loc *tp;
+ WARN_ON_ONCE(!addr);
+
if (!tp_vec_nr)
return true;
- if (!addr) /* force */
- return false;
-
/*
* If the last current entry's address is higher than the
* new entry's address we'd like to add, then ordering
@@ -2866,6 +2865,14 @@ static bool tp_addr_ordered(void *addr)
return true;
}
+void text_poke_int3_finish(void)
+{
+ if (tp_vec_nr) {
+ text_poke_int3_batch(tp_vec, tp_vec_nr);
+ tp_vec_nr = 0;
+ }
+}
+
static void text_poke_int3_flush(void *addr)
{
lockdep_assert_held(&text_mutex);
@@ -2876,11 +2883,6 @@ static void text_poke_int3_flush(void *addr)
}
}
-void text_poke_int3_finish(void)
-{
- text_poke_int3_flush(NULL);
-}
-
void __ref text_poke_int3_queue(void *addr, const void *opcode, size_t len, const void *emulate)
{
struct text_poke_int3_loc *tp;
--
2.45.2