From: Ingo Molnar <mingo@kernel.org>
Date: Fri, 11 Apr 2025 05:40:38 +0000 (+0200)
Subject: x86/alternatives: Assert input parameters in smp_text_poke_batch_process()
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=37725b64a9912292841cea7e9aebfd0f084ed8c0;p=users%2Fdwmw2%2Flinux.git

x86/alternatives: Assert input parameters in smp_text_poke_batch_process()

At this point the 'tp' input parameter must always be the
global 'tp_vec' array, and 'nr_entries' must always be equal
to 'tp_vec_nr'.

Assert these conditions - which will allow the removal of
a layer of indirection between these values.

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/20250411054105.2341982-27-mingo@kernel.org
---

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 329f6ee6b3bc2..4fa26a4351a64 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -2627,6 +2627,9 @@ static void smp_text_poke_batch_process(struct smp_text_poke_loc *tp, unsigned i
 
 	lockdep_assert_held(&text_mutex);
 
+	WARN_ON_ONCE(tp != tp_vec);
+	WARN_ON_ONCE(nr_entries != tp_vec_nr);
+
 	int3_vec.vec = tp;
 	int3_vec.nr_entries = nr_entries;