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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 50/53] x86/alternatives: Update the comments in smp_text_poke_batch_process()
Date: Fri, 11 Apr 2025 07:41:02 +0200	[thread overview]
Message-ID: <20250411054105.2341982-51-mingo@kernel.org> (raw)
In-Reply-To: <20250411054105.2341982-1-mingo@kernel.org>

 - Capitalize 'INT3' consistently,

 - make it clear that 'sync cores' means an SMP sync to all CPUs,

 - fix typos and spelling.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 arch/x86/kernel/alternative.c | 28 +++++++++++++++-------------
 1 file changed, 15 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index c0be0663425e..9ee6f879bce5 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -2561,24 +2561,26 @@ noinstr int smp_text_poke_int3_handler(struct pt_regs *regs)
 
 /**
  * smp_text_poke_batch_process() -- update instructions on live kernel on SMP
- * @text_poke_array.vec:		vector of instructions to patch
- * @text_poke_array.nr_entries:	number of entries in the vector
  *
- * Modify multi-byte instruction by using int3 breakpoint on SMP.
- * We completely avoid stop_machine() here, and achieve the
- * synchronization using int3 breakpoint.
+ * Input state:
+ *  text_poke_array.vec: vector of instructions to patch
+ *  text_poke_array.nr_entries: number of entries in the vector
+ *
+ * Modify multi-byte instructions by using INT3 breakpoints on SMP.
+ * We completely avoid using stop_machine() here, and achieve the
+ * synchronization using INT3 breakpoints and SMP cross-calls.
  *
  * The way it is done:
  *	- For each entry in the vector:
- *		- add a int3 trap to the address that will be patched
- *	- sync cores
+ *		- add an INT3 trap to the address that will be patched
+ *	- SMP sync all CPUs
  *	- For each entry in the vector:
  *		- update all but the first byte of the patched range
- *	- sync cores
+ *	- SMP sync all CPUs
  *	- For each entry in the vector:
- *		- replace the first byte (int3) by the first byte of
+ *		- replace the first byte (INT3) by the first byte of the
  *		  replacing opcode
- *	- sync cores
+ *	- SMP sync all CPUs
  */
 static void smp_text_poke_batch_process(void)
 {
@@ -2606,13 +2608,13 @@ static void smp_text_poke_batch_process(void)
 	cond_resched();
 
 	/*
-	 * Corresponding read barrier in int3 notifier for making sure the
+	 * Corresponding read barrier in INT3 notifier for making sure the
 	 * text_poke_array.nr_entries and handler are correctly ordered wrt. patching.
 	 */
 	smp_wmb();
 
 	/*
-	 * First step: add a int3 trap to the address that will be patched.
+	 * First step: add a INT3 trap to the address that will be patched.
 	 */
 	for (i = 0; i < text_poke_array.nr_entries; i++) {
 		text_poke_array.vec[i].old = *(u8 *)text_poke_addr(&text_poke_array.vec[i]);
@@ -2685,7 +2687,7 @@ static void smp_text_poke_batch_process(void)
 	}
 
 	/*
-	 * Third step: replace the first byte (int3) by the first byte of
+	 * Third step: replace the first byte (INT3) by the first byte of the
 	 * replacing opcode.
 	 */
 	for (do_sync = 0, i = 0; i < text_poke_array.nr_entries; i++) {
-- 
2.45.2


  parent reply	other threads:[~2025-04-11  5:43 UTC|newest]

Thread overview: 105+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-04-11  5:40 [PATCH -v3 00/53] Simplify, reorganize and clean up the x86 text-patching code (alternative.c) Ingo Molnar
2025-04-11  5:40 ` [PATCH 01/53] x86/alternatives: Improve code-patching scalability by removing false sharing in poke_int3_handler() Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Eric Dumazet
2025-04-11  5:40 ` [PATCH 02/53] x86/alternatives: Document the text_poke_bp_batch() synchronization rules a bit more Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Peter Zijlstra
2025-04-11  5:40 ` [PATCH 03/53] x86/alternatives: Rename 'struct bp_patching_desc' to 'struct int3_patching_desc' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] x86/alternatives: Rename 'struct bp_patching_desc' to 'struct text_poke_int3_vec' tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 04/53] x86/alternatives: Rename 'bp_refs' to 'int3_refs' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] x86/alternatives: Rename 'bp_refs' to 'text_poke_array_refs' tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 05/53] x86/alternatives: Rename 'text_poke_bp_batch()' to 'smp_text_poke_batch_process()' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 06/53] x86/alternatives: Rename 'text_poke_bp()' to 'smp_text_poke_single()' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 07/53] x86/alternatives: Rename 'poke_int3_handler()' to 'smp_text_poke_int3_handler()' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 08/53] x86/alternatives: Rename 'poking_mm' to 'text_poke_mm' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 09/53] x86/alternatives: Rename 'poking_addr' to 'text_poke_mm_addr' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 10/53] x86/alternatives: Rename 'bp_desc' to 'int3_desc' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 11/53] x86/alternatives: Remove duplicate 'text_poke_early()' prototype Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 12/53] x86/alternatives: Update comments in int3_emulate_push() Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 13/53] x86/alternatives: Remove the confusing, inaccurate & unnecessary 'temp_mm_state_t' abstraction Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 14/53] x86/alternatives: Rename 'text_poke_flush()' to 'smp_text_poke_batch_flush()' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 15/53] x86/alternatives: Rename 'text_poke_finish()' to 'smp_text_poke_batch_finish()' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 16/53] x86/alternatives: Rename 'text_poke_queue()' to 'smp_text_poke_batch_add()' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 17/53] x86/alternatives: Rename 'text_poke_loc_init()' to 'text_poke_int3_loc_init()' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 18/53] x86/alternatives: Rename 'struct text_poke_loc' to 'struct smp_text_poke_loc' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 19/53] x86/alternatives: Rename 'struct int3_patching_desc' to 'struct text_poke_int3_vec' Ingo Molnar
2025-04-11  5:40 ` [PATCH 20/53] x86/alternatives: Rename 'int3_desc' to 'int3_vec' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 21/53] x86/alternatives: Add text_mutex) assert to smp_text_poke_batch_flush() Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 22/53] x86/alternatives: Use non-inverted logic instead of 'tp_order_fail()' Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 23/53] 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
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 24/53] x86/alternatives: Simplify smp_text_poke_single() by using tp_vec and existing APIs Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 25/53] x86/alternatives: Assert that smp_text_poke_int3_handler() can only ever handle 'tp_vec[]' based requests Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 26/53] x86/alternatives: Assert input parameters in smp_text_poke_batch_process() Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 27/53] x86/alternatives: Introduce 'struct smp_text_poke_array' and move tp_vec and tp_vec_nr to it Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 28/53] x86/alternatives: Remove the tp_vec indirection Ingo Molnar
2025-04-11 10:02   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 29/53] x86/alternatives: Rename 'try_get_desc()' to 'try_get_text_poke_array()' Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 30/53] x86/alternatives: Rename 'put_desc()' to 'put_text_poke_array()' Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 31/53] x86/alternatives: Simplify try_get_text_poke_array() Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 32/53] x86/alternatives: Simplify smp_text_poke_int3_handler() Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 33/53] x86/alternatives: Simplify smp_text_poke_batch_process() Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 34/53] x86/alternatives: Rename 'int3_refs' to 'text_poke_array_refs' Ingo Molnar
2025-04-11  5:40 ` [PATCH 35/53] 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
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 36/53] x86/alternatives: Remove the mixed-patching restriction on smp_text_poke_single() Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 37/53] x86/alternatives: Document 'smp_text_poke_single()' Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 38/53] x86/alternatives: Add documentation for smp_text_poke_batch_add() Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 39/53] 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
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 40/53] x86/alternatives: Rename 'text_poke_sync()' to 'smp_text_poke_sync_each_cpu()' Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 41/53] x86/alternatives: Simplify text_poke_addr_ordered() Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 42/53] x86/alternatives: Constify text_poke_addr() Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 43/53] x86/alternatives: Simplify and clean up patch_cmp() Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 44/53] x86/alternatives: Standardize on 'tpl' local variable names for 'struct smp_text_poke_loc *' Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 45/53] x86/alternatives: Rename 'TP_ARRAY_NR_ENTRIES_MAX' to 'TEXT_POKE_ARRAY_MAX' Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 46/53] x86/alternatives: Rename 'POKE_MAX_OPCODE_SIZE' to 'TEXT_POKE_MAX_OPCODE_SIZE' Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:40 ` [PATCH 47/53] x86/alternatives: Simplify the #include section Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:41 ` [PATCH 48/53] x86/alternatives: Move declarations of vmlinux.lds.S defined section symbols to <asm/alternative.h> Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:41 ` [PATCH 49/53] x86/alternatives: Remove 'smp_text_poke_batch_flush()' Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:41 ` Ingo Molnar [this message]
2025-04-11 10:01   ` [tip: x86/alternatives] x86/alternatives: Update the comments in smp_text_poke_batch_process() tip-bot2 for Ingo Molnar
2025-04-11  5:41 ` [PATCH 51/53] x86/alternatives: Rename 'apply_relocation()' to 'text_poke_apply_relocation()' Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:41 ` [PATCH 52/53] x86/alternatives: Add comment about noinstr expectations Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Ingo Molnar
2025-04-11  5:41 ` [PATCH 53/53] x86/alternatives: Make smp_text_poke_batch_process() subsume smp_text_poke_batch_finish() Ingo Molnar
2025-04-11 10:01   ` [tip: x86/alternatives] " tip-bot2 for Nikolay Borisov

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