lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Sun, 12 Apr 2020 10:44:01 +0200
From:   Geert Uytterhoeven <>
To:     Sasha Levin <>
Cc:     Linux Kernel Mailing List <>,
        stable <>,
        Linux-Renesas <>,
        Linux ARM <>
Subject: Re: [PATCH AUTOSEL 5.4 095/108] ARM: shmobile: Enable
 ARM_GLOBAL_TIMER on Cortex-A9 MPCore SoCs

Hi Sasha,

On Sun, Apr 12, 2020 at 1:11 AM Sasha Levin <> wrote:
> From: Geert Uytterhoeven <>
> [ Upstream commit 408324a3c5383716939eea8096a0f999a0665f7e ]
> SH-Mobile AG5 and R-Car H1 SoCs are based on the Cortex-A9 MPCore, which
> includes a global timer.
> Enable the ARM global timer on these SoCs, which will be used for:
>   - the scheduler clock, improving scheduler accuracy from 10 ms to 3 or
>     4 ns,
>   - delay loops, allowing removal of calls to shmobile_init_delay() from
>     the corresponding machine vectors.
> Note that when using an old DTB lacking the global timer, the kernel
> will still work.  However, loops-per-jiffies will no longer be preset,
> and the delay loop will need to be calibrated during boot.

I.e. to avoid this delay, this patch is best backported after backporting
8443ffd1bbd5be74 ("ARM: dts: r8a7779: Add device node for ARM global timer"),
df1a0aac0a533e6f ("ARM: dts: sh73a0: Add device node for ARM global timer").

While the former has been backported to v5.[45]-stable, the latter hasn't,
probably because it depends on
61b58e3f6e518c51 ("ARM: dts: sh73a0: Rename twd clock to periph clock")

So please backport the last two commits first.

> Signed-off-by: Geert Uytterhoeven <>
> Link:
> Signed-off-by: Sasha Levin <>



Geert Uytterhoeven -- There's lots of Linux beyond ia32 --

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Powered by blists - more mailing lists