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From:   Vineet Gupta <vineet.gupta1@synopsys.com>
To:     Eugeniy Paltsev <eugeniy.paltsev@synopsys.com>,
        "linux-snps-arc@lists.infradead.org" 
        <linux-snps-arc@lists.infradead.org>
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        "peterz@infradead.org" <peterz@infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/2] ARC: show_regs: avoid page allocator
Thread-Topic: [PATCH 1/2] ARC: show_regs: avoid page allocator
Thread-Index: AQHUlwMR8PfsxZ55lUuwqgC40oqmmA==
Date:   Wed, 19 Dec 2018 17:36:35 +0000
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On 12/19/18 9:04 AM, Eugeniy Paltsev wrote:=0A=
> Just curious: isn't that enough to use GFP_NOWAIT instead=0A=
> of GFP_KERNEL when we allocate page in show_regs()?=0A=
>=0A=
> As I can see x86 use print_vma_addr() in their show_signal_msg()=0A=
> function which allocate page with __get_free_page(GFP_NOWAIT);=0A=
=0A=
I'm not sure if lockdep will be happy with it still.=0A=
=0A=
At any rate, as explained in changelog, this still has merit, since the buf=
fer is=0A=
only needed for nested d_path calls, which are better served with a smaller=
=0A=
on-stack buffer. For cases such as kernel crash, we want lesser code/traces=
 in=0A=
fault path to sift thru !=0A=
=0A=
-Vineet=0A=