linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: markivx@codeaurora.org (Vikram Mulukutla)
To: linux-arm-kernel@lists.infradead.org
Subject: spin_lock behavior with ARM64 big.Little/HMP
Date: Wed, 29 Mar 2017 21:12:23 -0700	[thread overview]
Message-ID: <537888bcf5dd5ea3c3418fc9e9e3ff79@codeaurora.org> (raw)
In-Reply-To: <f17207e7-e58c-2e42-04a8-50ed83a9616f@arm.com>


Hi Sudeep,

> 
> Interesting. Just curious if this is r0p0/p1 A53 ? If so, is the errata
> 819472 enabled ?

Sorry for bringing this up after the loo-ong delay, but I've been 
assured that the A53 involved is > r0p1. I've also confirmed this 
problem on multiple internal platforms, and I'm pretty sure that it 
occurs on any b.L out there today. Also, we found the same problematic 
lock design used in the workqueue code in the kernel, causing the same 
livelock. It's very very rare and requires a perfect set of 
circumstances.

If it would help I can provide a unit test if you folks would be 
generous enough to test it on the latest Juno or something b.L that's 
also upstream.

Thanks,
Vikram

  reply	other threads:[~2017-03-30  4:12 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-11-18  2:22 spin_lock behavior with ARM64 big.Little/HMP Vikram Mulukutla
2016-11-18 10:30 ` Sudeep Holla
2016-11-18 20:22   ` Vikram Mulukutla
2016-11-21 15:21     ` Sudeep Holla
2017-03-30  4:12       ` Vikram Mulukutla [this message]
2017-03-30 10:23         ` Sudeep Holla

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=537888bcf5dd5ea3c3418fc9e9e3ff79@codeaurora.org \
    --to=markivx@codeaurora.org \
    --cc=linux-arm-kernel@lists.infradead.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 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).