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Message-ID: <0690b548e233fba3758df0ce1eeca1c0803a62c4.camel@sipsolutions.net>
Subject: Re: [PATCH] net/fq_impl: Switch to kvmalloc() for memory allocation
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Toke =?ISO-8859-1?Q?H=F8iland-J=F8rgensen?= <toke@redhat.com>,
        linux-wireless@vger.kernel.org
Date:   Tue, 05 Nov 2019 16:51:37 +0100
In-Reply-To: <20191105154951.546285-1-toke@redhat.com>
References: <20191105154951.546285-1-toke@redhat.com>
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On Tue, 2019-11-05 at 16:49 +0100, Toke Høiland-Jørgensen wrote:
> The FQ implementation used by mac80211 allocates memory using kmalloc(),
> which can fail; and Johannes reported that this actually happens in
> practice.
> 
> To avoid this, switch the allocation to kvmalloc() instead; this also
> brings fq_impl in line with all the FQ qdiscs.
> 
> Fixes: 557fc4a09803 ("fq: add fair queuing framework")
> Reported-by: Johannes Berg <johannes@sipsolutions.net>
> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
> ---
>  include/net/fq_impl.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/include/net/fq_impl.h b/include/net/fq_impl.h
> index 107c0d700ed6..d3873db91c71 100644
> --- a/include/net/fq_impl.h
> +++ b/include/net/fq_impl.h
> @@ -313,7 +313,7 @@ static int fq_init(struct fq *fq, int flows_cnt)
>  	fq->limit = 8192;
>  	fq->memory_limit = 16 << 20; /* 16 MBytes */
>  
> -	fq->flows = kcalloc(fq->flows_cnt, sizeof(fq->flows[0]), GFP_KERNEL);
> +	fq->flows = kvcalloc(fq->flows_cnt, sizeof(fq->flows[0]), GFP_KERNEL);

You need a corresponding kvfree(), no?

johannes