From: Markus Elfring <Markus.Elfring@web.de>
To: "Heiko Stübner" <heiko@sntech.de>,
linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
linux-rockchip@lists.infradead.org,
kernel-janitors@vger.kernel.org
Cc: Michael Turquette <mturquette@baylibre.com>,
Stephen Boyd <sboyd@kernel.org>, Aditya Pakki <pakki001@umn.edu>,
Kangjie Lu <kjlu@umn.edu>, Navid Emamdoost <emamd001@umn.edu>,
Stephen McCamant <smccaman@umn.edu>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: clk: rockchip: Checking a kmemdup() call in rockchip_clk_register_pll()
Date: Mon, 14 Oct 2019 09:26:41 +0200 [thread overview]
Message-ID: <45588ab8-2a6c-3f29-61ff-bccf8d6fb291@web.de> (raw)
In-Reply-To: <2588953.0pqkEXWxhN@phil>
> The other option would be to panic, but the kernel should not
> panic if other options are available - and continuing with a static
> pll frequency is less invasive in the error case.
I would like to point out that this function implementation contains
the following source code already.
…
/* name the actual pll */
snprintf(pll_name, sizeof(pll_name), "pll_%s", name);
pll = kzalloc(sizeof(*pll), GFP_KERNEL);
if (!pll)
return ERR_PTR(-ENOMEM);
…
…
> +++ b/drivers/clk/rockchip/clk-pll.c
> @@ -909,14 +909,16 @@ struct clk *rockchip_clk_register_pll(struct rockchip_clk_provider *ctx,
…
> - pll->rate_count = len;
> pll->rate_table = kmemdup(rate_table,
> pll->rate_count *
> sizeof(struct rockchip_pll_rate_table),
> GFP_KERNEL);
> - WARN(!pll->rate_table,
> - "%s: could not allocate rate table for %s\n",
> - __func__, name);
> +
> + /*
> + * Set num rates to 0 if kmemdup fails. That way the clock
> + * at least can report its rate and stays usable.
> + */
> + pll->rate_count = pll->rate_table ? len : 0;
Can an other error handling strategy make sense occasionally?
…
if (!pll->rate_table) {
clk_unregister(mux_clk);
mux_clk = ERR_PTR(-ENOMEM);
goto err_mux;
}
…
Would you like to adjust such exception handling another bit?
Regards,
Markus
next prev parent reply other threads:[~2019-10-14 7:27 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-12 13:55 clk: rockchip: Checking a kmemdup() call in rockchip_clk_register_pll() Markus Elfring
2019-10-12 21:32 ` Heiko Stübner
2019-10-13 8:45 ` Markus Elfring
2019-10-13 21:49 ` Heiko Stuebner
2019-10-14 7:26 ` Markus Elfring [this message]
2019-10-15 20:29 ` Heiko Stuebner
2019-10-16 6:24 ` Markus Elfring
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