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>,
Ingo Molnar <mingo@kernel.org>
Subject: [PATCH 21/49] x86/alternatives: Use non-inverted logic instead of 'tp_order_fail()'
Date: Fri, 28 Mar 2025 14:26:36 +0100 [thread overview]
Message-ID: <20250328132704.1901674-22-mingo@kernel.org> (raw)
In-Reply-To: <20250328132704.1901674-1-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 'text_poke_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 5fe54f3c6211..66778dac257f 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 smp_text_poke_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 text_poke_addr_ordered(void *addr)
{
struct smp_text_poke_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_addr(tp) > (unsigned long)addr)
- return true;
+ return false;
- return false;
+ return true;
}
static void smp_text_poke_batch_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 || !text_poke_addr_ordered(addr)) {
smp_text_poke_batch_process(tp_vec, tp_vec_nr);
tp_vec_nr = 0;
}
--
2.45.2
next prev parent reply other threads:[~2025-03-28 13:28 UTC|newest]
Thread overview: 69+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-03-28 13:26 [PATCH -v2 00/49] Simplify, reorganize and clean up the x86 text-patching code (alternative.c) Ingo Molnar
2025-03-28 13:26 ` [PATCH 01/49] x86/alternatives: Rename 'struct bp_patching_desc' to 'struct int3_patching_desc' Ingo Molnar
2025-03-28 13:26 ` [PATCH 02/49] x86/alternatives: Rename 'bp_refs' to 'int3_refs' Ingo Molnar
2025-03-28 13:26 ` [PATCH 03/49] x86/alternatives: Rename 'text_poke_bp_batch()' to 'smp_text_poke_batch_process()' Ingo Molnar
2025-03-28 13:26 ` [PATCH 04/49] x86/alternatives: Rename 'text_poke_bp()' to 'smp_text_poke_single()' Ingo Molnar
2025-03-28 13:26 ` [PATCH 05/49] x86/alternatives: Rename 'poke_int3_handler()' to 'smp_text_poke_int3_trap_handler()' Ingo Molnar
2025-03-28 13:26 ` [PATCH 06/49] x86/alternatives: Rename 'poking_mm' to 'text_poke_mm' Ingo Molnar
2025-03-28 13:26 ` [PATCH 07/49] x86/alternatives: Rename 'poking_addr' to 'text_poke_mm_addr' Ingo Molnar
2025-03-28 13:26 ` [PATCH 08/49] x86/alternatives: Rename 'bp_desc' to 'int3_desc' Ingo Molnar
2025-03-28 13:26 ` [PATCH 09/49] x86/alternatives: Remove duplicate 'text_poke_early()' prototype Ingo Molnar
2025-03-28 13:26 ` [PATCH 10/49] x86/alternatives: Update comments in int3_emulate_push() Ingo Molnar
2025-03-28 13:26 ` [PATCH 11/49] x86/alternatives: Remove the confusing, inaccurate & unnecessary 'temp_mm_state_t' abstraction Ingo Molnar
2025-04-01 14:36 ` Peter Zijlstra
2025-04-01 19:06 ` Ingo Molnar
2025-04-02 4:07 ` Ingo Molnar
2025-04-02 7:54 ` Peter Zijlstra
2025-03-28 13:26 ` [PATCH 12/49] x86/alternatives: Rename 'text_poke_flush()' to 'smp_text_poke_batch_flush()' Ingo Molnar
2025-03-28 13:26 ` [PATCH 13/49] x86/alternatives: Rename 'text_poke_finish()' to 'smp_text_poke_batch_finish()' Ingo Molnar
2025-03-28 13:26 ` [PATCH 14/49] x86/alternatives: Rename 'text_poke_queue()' to 'smp_text_poke_batch_add()' Ingo Molnar
2025-03-28 13:26 ` [PATCH 15/49] x86/alternatives: Rename 'text_poke_loc_init()' to 'text_poke_int3_loc_init()' Ingo Molnar
2025-03-28 13:26 ` [PATCH 16/49] x86/alternatives: Rename 'struct text_poke_loc' to 'struct smp_text_poke_loc' Ingo Molnar
2025-03-28 13:26 ` [PATCH 17/49] x86/alternatives: Rename 'struct int3_patching_desc' to 'struct text_poke_int3_vec' Ingo Molnar
2025-03-28 13:26 ` [PATCH 18/49] x86/alternatives: Rename 'int3_desc' to 'int3_vec' Ingo Molnar
2025-03-28 13:26 ` [PATCH 19/49] x86/alternatives: Add text_mutex) assert to smp_text_poke_batch_flush() Ingo Molnar
2025-03-28 13:26 ` [PATCH 20/49] x86/alternatives: Assert that smp_text_poke_int3_trap_handler() can only ever handle 'tp_vec[]' based requests Ingo Molnar
2025-03-28 13:26 ` Ingo Molnar [this message]
2025-03-28 13:26 ` [PATCH 22/49] x86/alternatives: Remove the 'addr == NULL means forced-flush' hack from smp_text_poke_batch_finish()/smp_text_poke_batch_flush()/text_poke_addr_ordered() Ingo Molnar
2025-03-28 13:26 ` [PATCH 23/49] x86/alternatives: Simplify smp_text_poke_single() by using tp_vec and existing APIs Ingo Molnar
2025-04-01 14:40 ` Peter Zijlstra
2025-04-01 18:49 ` Ingo Molnar
2025-03-28 13:26 ` [PATCH 24/49] x86/alternatives: Assert input parameters in smp_text_poke_batch_process() Ingo Molnar
2025-03-28 13:26 ` [PATCH 25/49] x86/alternatives: Introduce 'struct smp_text_poke_array' and move tp_vec and tp_vec_nr to it Ingo Molnar
2025-03-28 13:26 ` [PATCH 26/49] x86/alternatives: Remove the tp_vec indirection Ingo Molnar
2025-03-28 13:26 ` [PATCH 27/49] x86/alternatives: Rename 'try_get_desc()' to 'try_get_text_poke_array()' Ingo Molnar
2025-03-28 13:26 ` [PATCH 28/49] x86/alternatives: Rename 'put_desc()' to 'put_text_poke_array()' Ingo Molnar
2025-03-28 13:26 ` [PATCH 29/49] x86/alternatives: Simplify try_get_text_poke_array() Ingo Molnar
2025-03-28 13:26 ` [PATCH 30/49] x86/alternatives: Simplify smp_text_poke_int3_trap_handler() Ingo Molnar
2025-03-28 13:26 ` [PATCH 31/49] x86/alternatives: Simplify smp_text_poke_batch_process() Ingo Molnar
2025-03-28 13:26 ` [PATCH 32/49] x86/alternatives: Rename 'int3_refs' to 'text_poke_array_refs' Ingo Molnar
2025-03-28 13:26 ` [PATCH 33/49] x86/alternatives: Move the text_poke_array manipulation into text_poke_int3_loc_init() and rename it to __smp_text_poke_batch_add() Ingo Molnar
2025-03-28 13:26 ` [PATCH 34/49] x86/alternatives: Remove the mixed-patching restriction on smp_text_poke_single() Ingo Molnar
2025-03-28 13:26 ` [PATCH 35/49] x86/alternatives: Document 'smp_text_poke_single()' Ingo Molnar
2025-03-28 13:26 ` [PATCH 36/49] x86/alternatives: Add documentation for smp_text_poke_batch_add() Ingo Molnar
2025-03-28 13:26 ` [PATCH 37/49] x86/alternatives: Move text_poke_array completion from smp_text_poke_batch_finish() and smp_text_poke_batch_flush() to smp_text_poke_batch_process() Ingo Molnar
2025-04-03 13:08 ` Nikolay Borisov
2025-04-03 13:38 ` Ingo Molnar
2025-04-03 13:41 ` Nikolay Borisov
2025-04-03 14:13 ` Ingo Molnar
2025-04-03 14:39 ` Nikolay Borisov
2025-04-03 15:29 ` Ingo Molnar
2025-04-03 15:34 ` Nikolay Borisov
2025-04-04 7:48 ` Ingo Molnar
2025-03-28 13:26 ` [PATCH 38/49] x86/alternatives: Rename 'text_poke_sync()' to 'smp_text_poke_sync_each_cpu()' Ingo Molnar
2025-03-28 13:26 ` [PATCH 39/49] x86/alternatives: Simplify text_poke_addr_ordered() Ingo Molnar
2025-03-28 13:26 ` [PATCH 40/49] x86/alternatives: Constify text_poke_addr() Ingo Molnar
2025-03-28 13:26 ` [PATCH 41/49] x86/alternatives: Simplify and clean up patch_cmp() Ingo Molnar
2025-03-28 13:26 ` [PATCH 42/49] x86/alternatives: Standardize on 'tpl' local variable names for 'struct smp_text_poke_loc *' Ingo Molnar
2025-03-28 13:26 ` [PATCH 43/49] x86/alternatives: Rename 'TP_ARRAY_NR_ENTRIES_MAX' to 'TEXT_POKE_ARRAY_MAX' Ingo Molnar
2025-03-28 13:26 ` [PATCH 44/49] x86/alternatives: Rename 'POKE_MAX_OPCODE_SIZE' to 'TEXT_POKE_MAX_OPCODE_SIZE' Ingo Molnar
2025-03-28 13:27 ` [PATCH 45/49] x86/alternatives: Simplify the #include section Ingo Molnar
2025-03-28 13:27 ` [PATCH 46/49] x86/alternatives: Move declarations of vmlinux.lds.S defined section symbols to <asm/alternative.h> Ingo Molnar
2025-03-28 13:27 ` [PATCH 47/49] x86/alternatives: Remove 'smp_text_poke_batch_flush()' Ingo Molnar
2025-03-28 13:27 ` [PATCH 48/49] x86/alternatives: Update the comments in smp_text_poke_batch_process() Ingo Molnar
2025-03-28 13:27 ` [PATCH 49/49] x86/alternatives: Rename 'apply_relocation()' to 'text_poke_apply_relocation()' Ingo Molnar
2025-04-01 14:31 ` [PATCH -v2 00/49] Simplify, reorganize and clean up the x86 text-patching code (alternative.c) Peter Zijlstra
2025-04-09 20:51 ` Ingo Molnar
2025-04-10 12:57 ` Peter Zijlstra
2025-04-01 14:31 ` Peter Zijlstra
2025-04-02 3:47 ` Ingo Molnar
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