From: Nishanth Menon <nm@ti.com>
To: Linus Walleij <linus.walleij@linaro.org>
Cc: Russell King <linux@armlinux.org.uk>,
<linux-arm-kernel@lists.infradead.org>,
Nishanth Menon <nmenon@kernel.org>
Subject: Re: [PATCH] ARM: Fix Keystone 2 kernel mapping regression
Date: Wed, 4 Aug 2021 11:40:33 -0500 [thread overview]
Message-ID: <20210804164033.5omplm7qs7fuxgfb@cupcake> (raw)
In-Reply-To: <20210804135747.737233-1-linus.walleij@linaro.org>
On 15:57-20210804, Linus Walleij wrote:
> This fixes a Keystone 2 regression discovered as a side effect of
> defining an passing the physical start/end sections of the kernel
> to the MMU remapping code.
>
> As the Keystone applies an offset to all physical addresses,
> including those identified and patches by phys2virt, we fail to
> account for this offset in the kernel_sec_start and kernel_sec_end
> variables.
>
> Further these offsets can extend into the 64bit range on LPAE
> systems such as the Keystone 2.
>
> Fix it like this:
> - Extend kernel_sec_start and kernel_sec_end to be 64bit
> - Add the offset also to kernel_sec_start and kernel_sec_end
>
> As passing kernel_sec_start and kernel_sec_end as 64bit invariably
> incurs endianness issues I have attempted to dry-code around
> these. Please review.
>
> Tested on the Vexpress QEMU model both with and without LPAE
> enabled.
>
> Fixes: 6e121df14ccd ("ARM: 9090/1: Map the lowmem and kernel separately")
> Reported-by: Nishanth Menon <nmenon@kernel.org>
> Suggested-by: Russell King <linux@armlinux.org.uk>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Nishanth Menon <nm@ti.com>
> Link: https://lore.kernel.org/r/20210804135747.737233-1-linus.walleij@linaro.org
> ---
> Nishanth: Please test!
> Other smart folks: please have a look at my endianness compensation
> assembly.
Russell, Linus - awesome. thanks for looking at the right problem.
test log (two k2 platforms from two generations):
Baseline(good): v5.13
k2g-evm: https://pastebin.ubuntu.com/p/xnGy9fM6mj/
k2hk-evm: https://pastebin.ubuntu.com/p/gpX6bPsF2R/
Check base(bad): v5.14-rc4
k2g-evm:
k2hk-evm: https://pastebin.ubuntu.com/p/ht7sTjyTD2/
k2g-evm: https://pastebin.ubuntu.com/p/skf8nsGqPZ/
Check patch: v5.14-rc4 + 20210804135747.737233-1-linus.walleij@linaro.org
k2hk-evm: https://pastebin.ubuntu.com/p/ycX7bmgcyT/
k2g-evm: https://pastebin.ubuntu.com/p/FgfZSwg7fY/
--
Regards,
Nishanth Menon
Key (0xDDB5849D1736249D) / Fingerprint: F8A2 8693 54EB 8232 17A3 1A34 DDB5 849D 1736 249D
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
prev parent reply other threads:[~2021-08-04 16:42 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-04 13:57 [PATCH] ARM: Fix Keystone 2 kernel mapping regression Linus Walleij
2021-08-04 14:10 ` Russell King (Oracle)
2021-08-04 16:23 ` Grygorii Strashko
2021-08-04 16:40 ` Nishanth Menon [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20210804164033.5omplm7qs7fuxgfb@cupcake \
--to=nm@ti.com \
--cc=linus.walleij@linaro.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux@armlinux.org.uk \
--cc=nmenon@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.