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Date:   Thu, 7 Jan 2021 11:27:22 -0500
From:   "Theodore Ts'o" <tytso@mit.edu>
To:     Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc:     Arnd Bergmann <arnd@kernel.org>, Will Deacon <will@kernel.org>,
        linux-toolchains@vger.kernel.org,
        Mark Rutland <mark.rutland@arm.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Andreas Dilger <adilger.kernel@dilger.ca>,
        Ext4 Developers List <linux-ext4@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: Aarch64 EXT4FS inode checksum failures - seems to be weak memory
 ordering issues
Message-ID: <X/c2aqSvYCaB9sR6@mit.edu>
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On Thu, Jan 07, 2021 at 01:37:47PM +0000, Russell King - ARM Linux admin wrote:
> > The gcc bugzilla mentions backports into gcc-linaro, but I do not see
> > them in my git history.
> 
> So, do we raise the minimum gcc version for the kernel as a whole to 5.1
> or just for aarch64?

Russell, Arnd, thanks so much for tracking down the root cause of the
bug!

I will note that RHEL 7 uses gcc 4.8.  I personally don't have an
objections to requiring developers using RHEL 7 to have to install a
more modern gcc (since I use Debian Testing and gcc 10.2.1, myself,
and gcc 5.1 is so five years ago :-), but I could imagine that being
considered inconvenient for some.

						- Ted