linux-kernel - Re: [PATCH V2] clk: zynq: do not allow kmalloc failure

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Message-ID: <154353512315.88331.4548631955021366823@swboyd.mtv.corp.google.com>
Date:   Thu, 29 Nov 2018 15:45:23 -0800
From:   Stephen Boyd <sboyd@...nel.org>
To:     Michael Turquette <mturquette@...libre.com>,
        Nicholas Mc Guire <hofrat@...dl.org>
Cc:     Michal Simek <michal.simek@...inx.com>,
        Rob Herring <robh@...nel.org>, linux-clk@...r.kernel.org,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        Nicholas Mc Guire <hofrat@...dl.org>
Subject: Re: [PATCH V2] clk: zynq: do not allow kmalloc failure

Quoting Nicholas Mc Guire (2018-11-21 04:28:30)
> The kmalloc here is small (< 16 bytes) and occurs during initialization
> during system startup here (can not be built as module) thus if this
> kmalloc failed it is an indication of something more serious going on
> and it is fine to hang the system here rather than cause some harder
> to understand error by dereferencing NULL.
> 
> Explicitly checking would not make that much sense here as the only
> possible reaction would be would BUG() here anyway.
> 
> Signed-off-by: Nicholas Mc Guire <hofrat@...dl.org>
> Fixes: 0ee52b157b8e ("clk: zynq: Add clock controller driver")
> Acked-by: Michal Simek <michal.simek@...inx.com>
> ---

Nak. We don't have any __GFP_NOFAIL in drivers/clk and I don't see a
reason why we would want it here either. Just handle the failure, or
don't care if this is so critical to system boot.