linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: Vicente Bergas <vicencb@gmail.com>
To: Robin Murphy <robin.murphy@arm.com>
Cc: Matthias Brugger <mbrugger@suse.com>,
	Heiko Stuebner <heiko@sntech.de>,
	Marc Zyngier <marc.zyngier@arm.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>,
	linux-rockchip@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org
Subject: Re: kexec on rk3399
Date: Mon, 22 Jul 2019 20:53:17 +0200	[thread overview]
Message-ID: <e42e7e24-a616-4a11-8c4d-1f44146e0a19@gmail.com> (raw)
In-Reply-To: <8f71e7de-7eaf-58c7-6471-c8eb01e656ce@arm.com>

On Monday, July 22, 2019 7:35:01 PM CEST, Robin Murphy wrote:
> On 22/07/2019 18:05, Vicente Bergas wrote:
>> On Monday, July 22, 2019 4:54:41 PM CEST, Marc Zyngier wrote: ...
>
> The obvious culprit would be DMA devices left running by the 
> first kernel scribbling over the second kernel's memory before 
> it's had the chance to reset them. Since boot-time memory 
> allocation patterns tend to be relatively repeatable for a given 
> platform and kernel configuration, "random" may well look a lot 
> less random than you might expect, and it wouldn't be unheard of 
> for e.g. the second kernel to mostly allocate its dentry cache 
> from the same area the first kernel was mostly putting a network 
> Rx descriptor ring.
>
> Robin.

Here is another attempted test: on the first kernel disable:
# CONFIG_ZONE_DMA32 is not set
# CONFIG_DMADEVICES is not set
# CONFIG_PL330_DMA is not set
that is, all i could disable matching CONFIG_*DMA*=y, which is not much.
Still enabled are:
CONFIG_HAVE_DMA_CONTIGUOUS=y
CONFIG_DMA_SHARED_BUFFER=y
CONFIG_SCSI_DMA=y
CONFIG_IOMMU_DMA=y
CONFIG_HAS_DMA=y
CONFIG_NEED_SG_DMA_LENGTH=y
CONFIG_NEED_DMA_MAP_STATE=y
CONFIG_ARCH_DMA_ADDR_T_64BIT=y
CONFIG_DMA_DECLARE_COHERENT=y
CONFIG_ARCH_HAS_SETUP_DMA_OPS=y
CONFIG_ARCH_HAS_TEARDOWN_DMA_OPS=y
CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE=y
CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU=y
CONFIG_ARCH_HAS_DMA_PREP_COHERENT=y
CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN=y
CONFIG_ARCH_HAS_DMA_MMAP_PGPROT=y
CONFIG_DMA_REMAP=y
CONFIG_DMA_DIRECT_REMAP=y

Then the second kernel still fails with d_lookup errors.

Regards,
  Vicenç.


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2019-07-22 18:53 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-22 14:31 kexec on rk3399 Vicente Bergas
2019-07-22 14:46 ` Will Deacon
2019-07-22 16:08   ` Vicente Bergas
2019-07-22 14:47 ` Matthias Brugger
2019-07-22 16:56   ` Vicente Bergas
2019-07-22 14:54 ` Marc Zyngier
2019-07-22 17:05   ` Vicente Bergas
2019-07-22 17:35     ` Robin Murphy
2019-07-22 18:53       ` Vicente Bergas [this message]
2019-07-23 13:32         ` Robin Murphy
2019-08-14 12:53 ` Vicente Bergas
2019-08-14 13:06   ` Felipe Balbi
2019-08-14 13:15     ` Vicente Bergas
2019-08-15  6:00       ` Felipe Balbi
2019-08-14 13:12   ` Robin Murphy
2019-08-15  1:15     ` Vicente Bergas
2019-08-15  6:06       ` Felipe Balbi
2019-08-15 11:09         ` Robin Murphy
2019-08-17 17:41           ` [PATCH] usb: dwc3: Add shutdown to platform_driver Vicente Bergas
2019-08-27 11:45             ` Vicente Bergas
2019-08-27 11:53               ` Felipe Balbi
2019-08-27 12:16                 ` Vicente Bergas
2019-09-09 15:07                   ` Vicente Bergas
2019-10-23  6:31                     ` Felipe Balbi
2019-10-24 12:15                       ` Vicente Bergas
2019-10-25 10:25                         ` Felipe Balbi
2019-10-25 10:42                           ` Vicente Bergas
2019-09-19 11:36             ` Vicente Bergas

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=e42e7e24-a616-4a11-8c4d-1f44146e0a19@gmail.com \
    --to=vicencb@gmail.com \
    --cc=catalin.marinas@arm.com \
    --cc=heiko@sntech.de \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-rockchip@lists.infradead.org \
    --cc=marc.zyngier@arm.com \
    --cc=mbrugger@suse.com \
    --cc=robin.murphy@arm.com \
    --cc=will.deacon@arm.com \
    /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).