From: "Zhang, Lei" <zhang.lei@jp.fujitsu.com>
To: 'Marc Zyngier' <marc.zyngier@arm.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>
Cc: Jeffrey Hugo <jhugo@codeaurora.org>,
Thomas Gleixner <tglx@linutronix.de>,
Jason Cooper <jason@lakedaemon.net>,
Jeremy Linton <jeremy.linton@arm.com>,
Ard Biesheuvel <ard.biesheuvel@linaro.org>
Subject: RE: [PATCH 00/10] GICv3 support for kexec/kdump on EFI systems
Date: Thu, 27 Sep 2018 13:01:01 +0000 [thread overview]
Message-ID: <8898674D84E3B24BA3A2D289B872026A6A005F4A@G01JPEXMBKW03> (raw)
In-Reply-To: <20180921195954.21574-1-marc.zyngier@arm.com>
Hi Marc
> -----Original Message-----
> From: linux-arm-kernel
> [mailto:linux-arm-kernel-bounces@lists.infradead.org] On Behalf Of Marc
> Zyngier
> Sent: Saturday, September 22, 2018 5:00 AM
> To: linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org
> Cc: Jeffrey Hugo; Thomas Gleixner; Jason Cooper; Jeremy Linton; Ard
> Biesheuvel
> Subject: [PATCH 00/10] GICv3 support for kexec/kdump on EFI systems
>
> The GICv3 architecture has the remarkable feature that once LPI tables
> have been assigned to redistributors and that LPI delivery is enabled,
> there is no guarantee that LPIs can be turned off (and most
> implementations do not allow it), nor can it be reprogrammed to use
> other tables.
>
> This is a bit of a problem for kexec, where the secondary kernel
> completely looses track of the previous allocations. If the secondary
> kernel doesn't allocate the tables exactly the same way, no LPIs will
> be delivered by the GIC (which continues to use the old tables), and
> memory previously allocated for the pending tables will be slowly
> corrupted, one bit at a time.
>
> The workaround for this is based on a series[1] by Ard Biesheuvel,
> which adds the required infrastructure for memory reservations to be
> passed from one kernel to another using an EFI table.
>
> This infrastructure is then used to register the allocation of GIC
> tables with EFI, and allow the GIC driver to safely reuse the existing
> programming if it detects that the tables have been correctly
> registered. On non-EFI systems, there is not much we can do.
>
> This has been tested on a TX2 system both as a host and a guest. I'd
> welcome additional testing of different HW. For convenience, I've
> stashed a branch containing the whole thing at [2].
We have done the test on our chip A64FX that When a write changes
EnableLPI bit from 0 to 1, this bit becomes RES1.
The result is that the kexec operation successfully works on our chip,
and PCI based on LPI also works after kexec.
For detail:
We did "kexec -e" command, and the message, "Using preallocated
redistributor tables", was shown.
After kexec, we can use our ssd normally.
Test environment
CPU: A64FX
Kernel version: v4.19 rc4 base
https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/log/?h=irq/gicv3-kdump
8bc67da irqchip/gic-v3-its: Allow use of LPI tables in reserved memory
kexec version:kexec-tools-2.0.14-17.2.el7.aarch64
Tested-by: Lei Zhang <zhang.lei@jp.fujitsu.com>
Thanks a lot.
Best Regards,
Lei,Zhang
FUJITSU LIMITED.
next prev parent reply other threads:[~2018-09-27 13:12 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-09-21 19:59 [PATCH 00/10] GICv3 support for kexec/kdump on EFI systems Marc Zyngier
2018-09-21 19:59 ` [PATCH 01/10] irqchip/gic-v3-its: Change initialization ordering for LPIs Marc Zyngier
2018-09-24 10:49 ` Julien Thierry
2018-09-21 19:59 ` [PATCH 02/10] irqchip/gic-v3-its: Consolidate LPI_PENDBASE_SZ usage Marc Zyngier
2018-09-24 10:33 ` Suzuki K Poulose
2018-09-24 10:50 ` Julien Thierry
2018-09-24 10:54 ` Suzuki K Poulose
2018-09-24 10:55 ` Julien Thierry
2018-09-26 10:28 ` Marc Zyngier
2018-09-21 19:59 ` [PATCH 03/10] irqchip/gic-v3-its: Split property table clearing from allocation Marc Zyngier
2018-09-21 19:59 ` [PATCH 04/10] irqchip/gic-v3-its: Move pending table allocation to init time Marc Zyngier
2018-09-24 11:58 ` Julien Thierry
2018-09-26 10:39 ` Marc Zyngier
2018-09-21 19:59 ` [PATCH 05/10] irqchip/gic-v3-its: Keep track of property table's PA and VA Marc Zyngier
2018-09-21 19:59 ` [PATCH 06/10] irqchip/gic-v3-its: Allow use of pre-programmed LPI tables Marc Zyngier
2018-09-24 12:52 ` Julien Thierry
2018-09-21 19:59 ` [PATCH 07/10] irqchip/gic-v3-its: Use pre-programmed redistributor tables with kdump kernels Marc Zyngier
2018-09-21 19:59 ` [PATCH 08/10] irqchip/gic-v3-its: Check that all RDs have the same property table Marc Zyngier
2018-09-21 19:59 ` [PATCH 09/10] irqchip/gic-v3-its: Register LPI tables with EFI config table Marc Zyngier
2018-09-21 19:59 ` [PATCH 10/10] irqchip/gic-v3-its: Allow use of LPI tables in reserved memory Marc Zyngier
2018-09-25 18:48 ` [PATCH 00/10] GICv3 support for kexec/kdump on EFI systems Jeremy Linton
2018-09-27 9:55 ` Bhupesh Sharma
2018-09-27 13:01 ` Zhang, Lei [this message]
2018-09-27 21:10 ` Richard Ruigrok
2018-09-28 10:33 ` Marc Zyngier
[not found] ` <CACiNFG5r2Czfy_kXA2PPQa=xdyzq0vUgoQZ=XNME4d_h=O1oBw@mail.gmail.com>
2019-02-01 9:15 ` Marc Zyngier
2019-02-02 3:05 ` Xulin Sun
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=8898674D84E3B24BA3A2D289B872026A6A005F4A@G01JPEXMBKW03 \
--to=zhang.lei@jp.fujitsu.com \
--cc=ard.biesheuvel@linaro.org \
--cc=jason@lakedaemon.net \
--cc=jeremy.linton@arm.com \
--cc=jhugo@codeaurora.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=marc.zyngier@arm.com \
--cc=tglx@linutronix.de \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).