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Date:   Thu, 25 May 2023 13:55:37 +0100
From:   Conor Dooley <conor.dooley@microchip.com>
To:     Atish Patra <atishp@atishpatra.org>
CC:     Alexandre Ghiti <alexghiti@rivosinc.com>,
        Anup Patel <anup@brainfault.org>,
        Song Shuai <suagrfillet@gmail.com>, <robh@kernel.org>,
        Andrew Jones <ajones@ventanamicro.com>, <palmer@rivosinc.com>,
        <jeeheng.sia@starfivetech.com>, <leyfoon.tan@starfivetech.com>,
        <mason.huo@starfivetech.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Guo Ren <guoren@kernel.org>, <linux-riscv@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>, <regressions@lists.linux.dev>
Subject: Re: Bug report: kernel paniced when system hibernates
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On Wed, May 24, 2023 at 04:53:59PM -0700, Atish Patra wrote:

> We can also just revert the commit
> 3335068 ("riscv: Use PUD/P4D/PGD pages for the linear mapping")
> until a proper solution is available.

I'm actually inclined to go the other day. If hibernation never works
in a released kernel we can't regress it & since we have not settled on
a fix for this yet we don't know whether the fix would then remove
support for hibernation where it used to work.

> IIRC, Alex also suggested the same as there is no measured benefit
> with this patch.
> It is good to have 1GB huge page mappings but it can be delayed until
> we have the fix
> for the hibernation issue.

IIRC it was the 1 GiB hugepages that Alex said were ~worthless.

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