From: Peter Zijlstra <peterz@infradead.org>
To: qiang.zhang@windriver.com
Cc: ryabinin.a.a@gmail.com, glider@google.com, dvyukov@google.com,
matthias.bgg@gmail.com, andreyknvl@google.com,
akpm@linux-foundation.org, oleg@redhat.com,
walter-zh.wu@mediatek.com, frederic@kernel.org,
kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org
Subject: [PATCH] irq_work: Make irq_work_queue() NMI-safe again
Date: Tue, 8 Jun 2021 19:59:23 +0200 [thread overview]
Message-ID: <YL+v+yMA1dZegUN9@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <YL+uBq8LzXXZsYVf@hirez.programming.kicks-ass.net>
On Tue, Jun 08, 2021 at 07:51:02PM +0200, Peter Zijlstra wrote:
> On Wed, Mar 31, 2021 at 02:32:02PM +0800, qiang.zhang@windriver.com wrote:
>
> > @@ -70,6 +70,9 @@ bool irq_work_queue(struct irq_work *work)
> > if (!irq_work_claim(work))
> > return false;
> >
> > + /*record irq_work call stack in order to print it in KASAN reports*/
> > + kasan_record_aux_stack(work);
> > +
> > /* Queue the entry and raise the IPI if needed. */
> > preempt_disable();
> > __irq_work_queue_local(work);
>
> Thanks for the Cc :/ Also NAK.
>
> I shall go revert this instantly. KASAN is not NMI safe, while
> irq_work_queue() is very carefully crafted to be exactly that.
The below goes in tip/perf/urgent ASAP.
---
Subject: irq_work: Make irq_work_queue() NMI-safe again
From: Peter Zijlstra <peterz@infradead.org>
Date: Tue Jun 8 19:54:15 CEST 2021
Someone carelessly put NMI unsafe code in irq_work_queue(), breaking
just about every single user. Also, someone has a terrible comment
style.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
---
kernel/irq_work.c | 3 ---
1 file changed, 3 deletions(-)
--- a/kernel/irq_work.c
+++ b/kernel/irq_work.c
@@ -70,9 +70,6 @@ bool irq_work_queue(struct irq_work *wor
if (!irq_work_claim(work))
return false;
- /*record irq_work call stack in order to print it in KASAN reports*/
- kasan_record_aux_stack(work);
-
/* Queue the entry and raise the IPI if needed. */
preempt_disable();
__irq_work_queue_local(work);
next prev parent reply other threads:[~2021-06-08 17:59 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-31 6:32 [PATCH] irq_work: record irq_work_queue() call stack qiang.zhang
2021-03-31 10:02 ` Dmitry Vyukov
2021-04-02 14:52 ` Andrey Konovalov
2021-06-08 17:51 ` Peter Zijlstra
2021-06-08 17:59 ` Peter Zijlstra [this message]
2021-06-10 7:02 ` [tip: perf/urgent] irq_work: Make irq_work_queue() NMI-safe again tip-bot2 for Peter Zijlstra
2021-06-10 8:13 ` tip-bot2 for Peter Zijlstra
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