x86/alternatives: Remove the 'addr == NULL means forced-flush' hack from smp_text_pok...

There's this weird hack used by smp_text_poke_batch_finish() to indicate
a 'forced flush':

	smp_text_poke_batch_flush(NULL);

Just open-code the vector-flush in a straightforward fashion:

	smp_text_poke_batch_process(tp_vec, tp_vec_nr);
	tp_vec_nr = 0;

And get rid of !addr hack from text_poke_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@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-24-mingo@kernel.org

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index c5801b4cbb66e5e80383faa77692462503fa4b6b..16a41e29db1792e0e842e7f0ad4b07625391c614 100644 (file)
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -2845,12 +2845,11 @@ static bool text_poke_addr_ordered(void *addr)
 {
        struct smp_text_poke_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
@@ -2864,6 +2863,14 @@ static bool text_poke_addr_ordered(void *addr)
        return true;
 }
 
+void smp_text_poke_batch_finish(void)
+{
+       if (tp_vec_nr) {
+               smp_text_poke_batch_process(tp_vec, tp_vec_nr);
+               tp_vec_nr = 0;
+       }
+}
+
 static void smp_text_poke_batch_flush(void *addr)
 {
        lockdep_assert_held(&text_mutex);
@@ -2874,11 +2881,6 @@ static void smp_text_poke_batch_flush(void *addr)
        }
 }
 
-void smp_text_poke_batch_finish(void)
-{
-       smp_text_poke_batch_flush(NULL);
-}
-
 void __ref smp_text_poke_batch_add(void *addr, const void *opcode, size_t len, const void *emulate)
 {
        struct smp_text_poke_loc *tp;