From: "tip-bot2 for Peter Zijlstra" <tip-bot2@linutronix.de>
To: linux-tip-commits@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>,
"Peter Zijlstra (Intel)" <peterz@infradead.org>,
Masami Hiramatsu <mhiramat@kernel.org>,
Alexandre Chartre <alexandre.chartre@oracle.com>,
Andy Lutomirski <luto@kernel.org>, x86 <x86@kernel.org>,
LKML <linux-kernel@vger.kernel.org>
Subject: [tip: x86/entry] x86/int3: Avoid atomic instrumentation
Date: Tue, 19 May 2020 19:58:27 -0000 [thread overview]
Message-ID: <158991830703.17951.7301728008554770838.tip-bot2@tip-bot2> (raw)
In-Reply-To: <20200505135313.517429268@linutronix.de>
The following commit has been merged into the x86/entry branch of tip:
Commit-ID: a53a1d0435cdc2b66f41f75fa1cee31e8fe6d99e
Gitweb: https://git.kernel.org/tip/a53a1d0435cdc2b66f41f75fa1cee31e8fe6d99e
Author: Peter Zijlstra <peterz@infradead.org>
AuthorDate: Fri, 24 Jan 2020 22:08:45 +01:00
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitterDate: Tue, 19 May 2020 16:04:05 +02:00
x86/int3: Avoid atomic instrumentation
Use arch_atomic_*() and __READ_ONCE() to ensure nothing untoward
creeps in and ruins things.
That is; this is the INT3 text poke handler, strictly limit the code
that runs in it, lest it inadvertenly hits yet another INT3.
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200505135313.517429268@linutronix.de
---
arch/x86/kernel/alternative.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 1f4cb2c..686c8ac 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -960,9 +960,9 @@ static struct bp_patching_desc *bp_desc;
static __always_inline
struct bp_patching_desc *try_get_desc(struct bp_patching_desc **descp)
{
- struct bp_patching_desc *desc = READ_ONCE(*descp); /* rcu_dereference */
+ struct bp_patching_desc *desc = __READ_ONCE(*descp); /* rcu_dereference */
- if (!desc || !atomic_inc_not_zero(&desc->refs))
+ if (!desc || !arch_atomic_inc_not_zero(&desc->refs))
return NULL;
return desc;
@@ -971,7 +971,7 @@ struct bp_patching_desc *try_get_desc(struct bp_patching_desc **descp)
static __always_inline void put_desc(struct bp_patching_desc *desc)
{
smp_mb__before_atomic();
- atomic_dec(&desc->refs);
+ arch_atomic_dec(&desc->refs);
}
static __always_inline void *text_poke_addr(struct text_poke_loc *tp)
next prev parent reply other threads:[~2020-05-19 19:58 UTC|newest]
Thread overview: 94+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-05 13:49 [patch V4 part 4 00/24] x86/entry: Entry/exception code rework, nasty exceptions Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 01/24] x86/int3: Ensure that poke_int3_handler() is not traced Thomas Gleixner
2020-05-14 4:57 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 02/24] x86/int3: Avoid atomic instrumentation Thomas Gleixner
2020-05-08 13:27 ` Masami Hiramatsu
2020-05-14 4:57 ` Andy Lutomirski
2020-05-14 9:32 ` Peter Zijlstra
2020-05-14 12:51 ` Thomas Gleixner
2020-05-14 13:15 ` Peter Zijlstra
2020-05-14 14:55 ` Andy Lutomirski
2020-05-14 15:06 ` Thomas Gleixner
2020-05-14 15:08 ` Andy Lutomirski
2020-05-14 15:10 ` Peter Zijlstra
2020-05-19 19:58 ` tip-bot2 for Peter Zijlstra [this message]
2020-05-05 13:49 ` [patch V4 part 4 03/24] lib/bsearch: Provide __always_inline variant Thomas Gleixner
2020-05-14 4:58 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-05-05 13:49 ` [patch V4 part 4 04/24] x86/int3: Inline bsearch() Thomas Gleixner
2020-05-14 4:58 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-05-05 13:49 ` [patch V4 part 4 05/24] x86/entry: Provide IDTENTRY_RAW Thomas Gleixner
2020-05-14 4:59 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] x86/idtentry: " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 06/24] x86/entry: Convert INT3 exception to IDTENTRY_RAW Thomas Gleixner
2020-05-14 5:01 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 07/24] x86/traps: Split int3 handler up Thomas Gleixner
2020-05-14 5:03 ` Andy Lutomirski
2020-05-14 9:39 ` Peter Zijlstra
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-05-05 13:49 ` [patch V4 part 4 08/24] x86/entry: Provide IDTENTRY_IST Thomas Gleixner
2020-05-14 16:39 ` Andy Lutomirski
2020-05-14 18:44 ` Thomas Gleixner
2020-05-19 19:58 ` [tip: x86/entry] x86/idtentry: " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 09/24] x86/mce: Move nmi_enter/exit() into the entry point Thomas Gleixner
2020-05-15 5:23 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 10/24] x86/entry: Convert Machine Check to IDTENTRY_IST Thomas Gleixner
2020-05-15 5:24 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 11/24] x86/mce: Use untraced rd/wrmsr in the MCE offline/crash check Thomas Gleixner
2020-05-15 5:24 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 12/24] x86/idtentry: Provide IDTENTRY_XEN for XEN/PV Thomas Gleixner
2020-05-15 5:25 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 13/24] x86/entry: Convert NMI to IDTENTRY_NMI Thomas Gleixner
2020-05-15 5:26 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 14/24] x86/nmi: Protect NMI entry against instrumentation Thomas Gleixner
2020-05-15 5:26 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 15/24] x86/db: Split out dr6/7 handling Thomas Gleixner
2020-05-07 17:18 ` Alexandre Chartre
2020-05-08 8:59 ` Peter Zijlstra
2020-05-08 11:58 ` Thomas Gleixner
2020-05-08 12:45 ` Peter Zijlstra
2020-05-14 2:24 ` Mathieu Desnoyers
2020-05-14 17:28 ` Thomas Gleixner
2020-05-14 17:46 ` Mathieu Desnoyers
2020-05-15 14:32 ` Thomas Gleixner
2020-05-14 18:06 ` Steven Rostedt
2020-05-15 5:37 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Peter Zijlstra
2020-05-05 13:49 ` [patch V4 part 4 16/24] x86/entry: Convert Debug exception to IDTENTRY_DB Thomas Gleixner
2020-05-15 5:27 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 17/24] x86/entry/64: Remove error code clearing from #DB and #MCE ASM stub Thomas Gleixner
2020-05-15 5:27 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 18/24] x86/entry: Provide IDTRENTRY_NOIST variants for #DB and #MC Thomas Gleixner
2020-05-15 5:29 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] x86/idtentry: " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 19/24] x86/entry: Implement user mode C entry points for #DB and #MCE Thomas Gleixner
2020-05-15 5:32 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 20/24] x86/traps: Restructure #DB handling Thomas Gleixner
2020-05-15 5:39 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 21/24] x86/traps: Address objtool noinstr complaints in #DB Thomas Gleixner
2020-05-15 5:39 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 22/24] x86/mce: Address objtools noinstr complaints Thomas Gleixner
2020-05-15 5:40 ` Andy Lutomirski
2020-05-19 19:58 ` [tip: x86/entry] " tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 23/24] x86/entry: Provide IDTENTRY_DF Thomas Gleixner
2020-05-15 5:41 ` Andy Lutomirski
2020-05-15 15:01 ` Thomas Gleixner
2020-05-19 19:58 ` [tip: x86/entry] x86/idtentry: " tip-bot2 for Thomas Gleixner
2020-05-19 19:58 ` [tip: x86/entry] x86/entry: Convert double fault exception to IDTENTRY_DF tip-bot2 for Thomas Gleixner
2020-05-05 13:49 ` [patch V4 part 4 24/24] " Thomas Gleixner
2020-05-07 19:55 ` Alexandre Chartre
2020-05-15 5:42 ` Andy Lutomirski
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