linux-kernel - Re: [PATCH] efi/arm: fix allocation failure when reserving the kernel base

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Message-ID: <20190820115409.GO13294@shell.armlinux.org.uk>
Date:   Tue, 20 Aug 2019 12:54:09 +0100
From:   Russell King - ARM Linux admin <linux@...linux.org.uk>
To:     Ard Biesheuvel <ard.biesheuvel@...aro.org>
Cc:     Chester Lin <clin@...e.com>,
        "akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
        "rppt@...ux.ibm.com" <rppt@...ux.ibm.com>,
        "ren_guo@...ky.com" <ren_guo@...ky.com>,
        Juergen Gross <JGross@...e.com>,
        "geert@...ux-m68k.org" <geert@...ux-m68k.org>,
        "mingo@...nel.org" <mingo@...nel.org>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux-efi@...r.kernel.org" <linux-efi@...r.kernel.org>,
        "guillaume.gardet@....com" <guillaume.gardet@....com>,
        Joey Lee <JLee@...e.com>, Gary Lin <GLin@...e.com>
Subject: Re: [PATCH] efi/arm: fix allocation failure when reserving the
 kernel base

On Sun, Aug 04, 2019 at 10:57:00AM +0300, Ard Biesheuvel wrote:
> (The first TEXT_OFFSET bytes are no longer used in practice, which is
> why putting a reserved region of 4 KB bytes works at the moment, but
> this is fragile).

That is not correct for 32-bit ARM.  The swapper page table is still
located 16kiB below the kernel.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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