From: Ingo Molnar <mingo@kernel.org>
To: linux-kernel@vger.kernel.org
Cc: Juergen Gross <jgross@suse.com>,
"H . Peter Anvin" <hpa@zytor.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Peter Zijlstra <peterz@infradead.org>,
Borislav Petkov <bp@alien8.de>,
Thomas Gleixner <tglx@linutronix.de>
Subject: [PATCH 22/41] x86/alternatives: Use non-inverted logic instead of 'tp_order_fail()'
Date: Thu, 27 Mar 2025 21:53:35 +0100 [thread overview]
Message-ID: <20250327205355.378659-23-mingo@kernel.org> (raw)
In-Reply-To: <20250327205355.378659-1-mingo@kernel.org>
tp_order_fail() uses inverted logic: it returns true in case something
is false, which is only a plus at the IOCCC.
Instead rename it to regular parity as 'tp_addr_ordered()',
and adjust the code accordingly.
Also add a comment explaining how the address ordering should be
understood.
No change in functionality intended.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/kernel/alternative.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 883c2146ce54..938e8e70a379 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -2843,28 +2843,34 @@ static void text_poke_int3_loc_init(struct text_poke_int3_loc *tp, void *addr,
* We hard rely on the tp_vec being ordered; ensure this is so by flushing
* early if needed.
*/
-static bool tp_order_fail(void *addr)
+static bool tp_addr_ordered(void *addr)
{
struct text_poke_int3_loc *tp;
if (!tp_vec_nr)
- return false;
+ return true;
if (!addr) /* force */
- return true;
+ return false;
- tp = &tp_vec[tp_vec_nr - 1];
+ /*
+ * If the last current entry's address is higher than the
+ * new entry's address we'd like to add, then ordering
+ * is violated and we must first flush all pending patching
+ * requests:
+ */
+ tp = &tp_vec[tp_vec_nr-1];
if ((unsigned long)text_poke_int3_addr(tp) > (unsigned long)addr)
- return true;
+ return false;
- return false;
+ return true;
}
static void text_poke_int3_flush(void *addr)
{
lockdep_assert_held(&text_mutex);
- if (tp_vec_nr == TP_VEC_MAX || tp_order_fail(addr)) {
+ if (tp_vec_nr == TP_VEC_MAX || !tp_addr_ordered(addr)) {
text_poke_int3_batch(tp_vec, tp_vec_nr);
tp_vec_nr = 0;
}
--
2.45.2
next prev parent reply other threads:[~2025-03-27 20:54 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-03-27 20:53 [PATCH 00/41] Simplify, reorganize and clean up the x86 INT3 based batch-patching code (alternative.c) Ingo Molnar
2025-03-27 20:53 ` [PATCH 01/41] x86/alternatives: Rename 'struct bp_patching_desc' to 'struct int3_patching_desc' Ingo Molnar
2025-03-27 20:53 ` [PATCH 02/41] x86/alternatives: Rename 'bp_refs' to 'int3_refs' Ingo Molnar
2025-03-27 20:53 ` [PATCH 03/41] x86/alternatives: Rename 'text_poke_bp_batch()' to 'text_poke_int3_batch()' Ingo Molnar
2025-03-27 20:53 ` [PATCH 04/41] x86/alternatives: Rename 'text_poke_bp()' to 'text_poke_int3()' Ingo Molnar
2025-03-27 20:53 ` [PATCH 05/41] x86/alternatives: Rename 'poke_int3_handler()' to 'text_poke_int3_handler()' Ingo Molnar
2025-03-27 20:53 ` [PATCH 06/41] x86/alternatives: Rename 'poking_mm' to 'text_poke_mm' Ingo Molnar
2025-03-27 20:53 ` [PATCH 07/41] x86/alternatives: Rename 'text_poke_addr' to 'text_poke_int3_addr' Ingo Molnar
2025-03-27 20:53 ` [PATCH 08/41] x86/alternatives: Rename 'poking_addr' to 'text_poke_addr' Ingo Molnar
2025-03-27 20:53 ` [PATCH 09/41] x86/alternatives: Rename 'bp_desc' to 'int3_desc' Ingo Molnar
2025-03-27 20:53 ` [PATCH 10/41] x86/alternatives: Remove duplicate 'text_poke_early()' prototype Ingo Molnar
2025-03-27 20:53 ` [PATCH 11/41] x86/alternatives: Update comments in int3_emulate_push() Ingo Molnar
2025-03-27 20:53 ` [PATCH 12/41] x86/alternatives: Remove the confusing, inaccurate & unnecessary 'temp_mm_state_t' abstraction Ingo Molnar
2025-03-27 20:53 ` [PATCH 13/41] x86/alternatives: Rename 'text_poke_flush()' to 'text_poke_int3_flush()' Ingo Molnar
2025-03-27 20:53 ` [PATCH 14/41] x86/alternatives: Rename 'text_poke_finish()' to 'text_poke_int3_finish()' Ingo Molnar
2025-03-27 20:53 ` [PATCH 15/41] x86/alternatives: Rename 'text_poke_queue()' to 'text_poke_int3_queue()' Ingo Molnar
2025-03-27 20:53 ` [PATCH 16/41] x86/alternatives: Rename 'text_poke_loc_init()' to 'text_poke_int3_loc_init()' Ingo Molnar
2025-03-27 20:53 ` [PATCH 17/41] x86/alternatives: Rename 'struct text_poke_loc' to 'struct text_poke_int3_loc' Ingo Molnar
2025-03-27 20:53 ` [PATCH 18/41] x86/alternatives: Rename 'struct int3_patching_desc' to 'struct text_poke_int3_vec' Ingo Molnar
2025-03-27 20:53 ` [PATCH 19/41] x86/alternatives: Rename 'int3_desc' to 'int3_vec' Ingo Molnar
2025-03-27 20:53 ` [PATCH 20/41] x86/alternatives: Add text_mutex) assert to text_poke_int3_flush() Ingo Molnar
2025-03-27 20:53 ` [PATCH 21/41] x86/alternatives: Assert that text_poke_int3_handler() can only ever handle 'tp_vec[]' based requests Ingo Molnar
2025-03-27 20:53 ` Ingo Molnar [this message]
2025-03-27 20:53 ` [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() Ingo Molnar
2025-03-27 20:53 ` [PATCH 24/41] x86/alternatives: Simplify text_poke_int3() by using tp_vec and existing APIs Ingo Molnar
2025-03-27 20:53 ` [PATCH 25/41] x86/alternatives: Assert input parameters in text_poke_int3_batch() Ingo Molnar
2025-03-27 20:53 ` [PATCH 26/41] x86/alternatives: Introduce 'struct text_poke_int3_array' and move tp_vec and tp_vec_nr to it Ingo Molnar
2025-03-27 20:53 ` [PATCH 27/41] x86/alternatives: Remove the tp_vec indirection Ingo Molnar
2025-03-27 20:53 ` [PATCH 28/41] x86/alternatives: Rename 'try_get_desc()' to 'try_get_tp_array()' Ingo Molnar
2025-03-27 20:53 ` [PATCH 29/41] x86/alternatives: Rename 'put_desc()' to 'put_tp_array()' Ingo Molnar
2025-03-27 20:53 ` [PATCH 30/41] x86/alternatives: Simplify try_get_tp_array() Ingo Molnar
2025-03-27 20:53 ` [PATCH 31/41] x86/alternatives: Simplify text_poke_int3_handler() Ingo Molnar
2025-03-27 20:53 ` [PATCH 32/41] x86/alternatives: Simplify text_poke_int3_batch() Ingo Molnar
2025-03-27 20:53 ` [PATCH 33/41] x86/alternatives: Rename 'text_poke_int3_batch()' to 'text_poke_int3_batch_process()' Ingo Molnar
2025-03-27 20:53 ` [PATCH 34/41] x86/alternatives: Rename 'int3_refs' to 'tp_array_refs' Ingo Molnar
2025-03-27 20:53 ` [PATCH 35/41] x86/alternatives: Move the tp_array manipulation into text_poke_int3_loc_init() and rename it to text_poke_int3_loc_add() Ingo Molnar
2025-03-27 20:53 ` [PATCH 36/41] x86/alternatives: Remove the mixed-patching restriction on text_poke_int3() Ingo Molnar
2025-03-27 20:53 ` [PATCH 37/41] x86/alternatives: Rename 'text_poke_int3()' to 'text_poke_int3_now()' Ingo Molnar
2025-03-27 20:53 ` [PATCH 38/41] x86/alternatives: Add documentation for text_poke_int3_queue() Ingo Molnar
2025-03-27 20:53 ` [PATCH 39/41] x86/alternatives: Move tp_array completion from text_poke_int3_finish() and text_poke_int3_flush() to text_poke_int3_batch_process() Ingo Molnar
2025-03-27 20:53 ` [PATCH 40/41] x86/alternatives: Rename 'text_poke_sync()' to 'text_poke_sync_each_cpu()' Ingo Molnar
2025-04-02 4:10 ` H. Peter Anvin
2025-04-03 15:05 ` Ingo Molnar
2025-03-27 20:53 ` [PATCH 41/41] x86/alternatives: Simplify tp_addr_ordered() Ingo Molnar
2025-03-27 22:19 ` [PATCH 00/41] Simplify, reorganize and clean up the x86 INT3 based batch-patching code (alternative.c) Linus Torvalds
2025-03-28 10:10 ` Ingo Molnar
2025-04-01 14:55 ` Peter Zijlstra
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