On 12/29/2014 08:13 PM, Mark Rutland wrote:

[Adding Arnd]

On Mon, Dec 29, 2014 at 08:35:09AM +0000, Christoffer Dall wrote:

quoted

On Sun, Dec 28, 2014 at 09:46:20PM +0000, Marc Zyngier wrote:

quoted

On 2014-12-28 14:20, Christoffer Dall wrote:

quoted

Commit 0b46b8a718c6e ("clocksource: arch_timer: Fix code to...")
fixes
timer issues with certain ARMv7 platforms, but unfortunately breaks
arm64 platforms with hyp mode (EL2) enabled.

The commit only sets arch_timer_use_virtual to false under
CONFIG_ARM,
but forgets that the config variable is also set in other code paths
(actually, right underneath the check in the patch) with detrimental
consequences as we've now introduced a direct early call to BUG() on
practically all arm64 platforms.

One could argue that this code could be refactored to use different
variables for checking which *timer* to use and which *counter* to
use,
which seems to be the desired difference between ARM and arm64 in
this
case, but this approach fixes an urgent issue for now.

Cc: Sonny Rao <redacted>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Daniel Lezcano <redacted>
Cc: Olof Johansson <redacted>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <redacted>
Cc: Yingjoe Chen <redacted>
Signed-off-by: Christoffer Dall <redacted>
---
This was apparently already discovered by Yingjoe Chen in this thread
https://lkml.org/lkml/2014/11/24/41 and Catalin recommended a similar
fix.

I'm increasingly worried about the time it takes to get such critical
fixes into the tree (arm64 is *dead* without it).

What is holding this patch which, as far as I remember, has been posted
by Catalin almost three weeks ago?

I didn't find that since I didn't think I'd have to go back that long on
lakml for something that breaks boot of an entire architecture.  Sorry
for the confusion of a second patch, but fwiw, I now spent another few
hours bisecting this, so I would really like to see this fix go into
mainline ASAP as well to save others the trouble.

Last I knew, Arnd was going to take the fix [1], which has been in
arm-soc's for-next and fixes branches for almost two weeks now. It
didn't make it into the last pull req due to some confusion over who was
going to take it.

I asked arm-soc team to take the fix because it was depending on a patch 
which was already in their tree [1].

Merry Christmas

   -- Daniel

[1] http://www.spinics.net/lists/arm-kernel/msg385704.html

Arnd, what's the plan for getting this into mainline ASAP?

Mark.

[1] https://git.kernel.org/cgit/linux/kernel/git/arm/arm-soc.git/commit/?h=fixes&id=d6ad36913083d683aad4e02e53580c995f1a6ede

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