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From:   Marco Elver <elver@google.com>
Date:   Fri, 17 Apr 2020 11:23:05 +0200
Message-ID: <CANpmjNMzwqFaaA-zQh0Nv4SUdoJUFO_yTmTjfbMFqyxBea1U+Q@mail.gmail.com>
Subject: Re: [PATCH -next] kcsan: Use GFP_ATOMIC under spin lock
To:     Wei Yongjun <weiyongjun1@huawei.com>,
        "Paul E. McKenney" <paulmck@kernel.org>
Cc:     Dmitry Vyukov <dvyukov@google.com>,
        kasan-dev <kasan-dev@googlegroups.com>,
        LKML <linux-kernel@vger.kernel.org>,
        kernel-janitors@vger.kernel.org
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On Fri, 17 Apr 2020 at 04:56, Wei Yongjun <weiyongjun1@huawei.com> wrote:
>
> A spin lock is taken here so we should use GFP_ATOMIC.
>
> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>

Good catch, thank you!

Reviewed-by: Marco Elver <elver@google.com>


> ---
>  kernel/kcsan/debugfs.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/kernel/kcsan/debugfs.c b/kernel/kcsan/debugfs.c
> index 1a08664a7fab..023e49c58d55 100644
> --- a/kernel/kcsan/debugfs.c
> +++ b/kernel/kcsan/debugfs.c
> @@ -230,7 +230,7 @@ static ssize_t insert_report_filterlist(const char *func)
>                 /* initial allocation */
>                 report_filterlist.addrs =
>                         kmalloc_array(report_filterlist.size,
> -                                     sizeof(unsigned long), GFP_KERNEL);
> +                                     sizeof(unsigned long), GFP_ATOMIC);
>                 if (report_filterlist.addrs == NULL) {
>                         ret = -ENOMEM;
>                         goto out;
> @@ -240,7 +240,7 @@ static ssize_t insert_report_filterlist(const char *func)
>                 size_t new_size = report_filterlist.size * 2;
>                 unsigned long *new_addrs =
>                         krealloc(report_filterlist.addrs,
> -                                new_size * sizeof(unsigned long), GFP_KERNEL);
> +                                new_size * sizeof(unsigned long), GFP_ATOMIC);
>
>                 if (new_addrs == NULL) {
>                         /* leave filterlist itself untouched */
>
>
>
>
>