From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
"Qixuan.Wu" <qixuan.wu@linux.alibaba.com>,
linux-kernel-owner <linux-kernel-owner@vger.kernel.org>,
Petr Mladek <pmladek@suse.com>, Jan Kara <jack@suse.cz>,
linux-kernel <linux-kernel@vger.kernel.org>,
Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
"chenggang.qin" <chenggang.qin@linux.alibaba.com>,
caijingxian <caijingxian@linux.alibaba.com>,
"yuanliang.wyl" <yuanliang.wyl@alibaba-inc.com>
Subject: Re: Would you help to tell why async printk solution was not taken to upstream kernel ?
Date: Tue, 6 Mar 2018 11:53:50 +0900 [thread overview]
Message-ID: <20180306025350.GD6713@jagdpanzerIV> (raw)
In-Reply-To: <20180305214701.7434d030@gandalf.local.home>
On (03/05/18 21:47), Steven Rostedt wrote:
[..]
> At this moment all watchdogs are working fine. And the continuing will
> be done as if it was the first printk. No lockup eminent.
>
[..]
> So basically, the CPU is just printing what that CPU is printing. It
> only becomes an issue if the system has an issue (one CPU spamming
> printk). Which is another bug.
>
[..]
> Which is another issue as well. But this is due to issues with printk
> having issues, and is a different category of bug.
>
> #2 and #3 are more recursive bugs and not a "printk locks up due to
> other CPUs" kind of bug.
Yes. My point was that "CPU can print one full buffer max" is not
guaranteed and not exactly true. There are ways for CPUs to break
that O(logbuf) boundary.
-ss
next prev parent reply other threads:[~2018-03-06 2:53 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <1eb584e2-a479-46dd-8a25-820da7a34e85.qixuan.wu@linux.alibaba.com>
2018-03-04 13:01 ` Would you help to tell why async printk solution was not taken to upstream kernel ? Sergey Senozhatsky
2018-03-04 15:08 ` Qixuan.Wu
2018-03-04 15:43 ` Steven Rostedt
2018-03-05 2:14 ` Sergey Senozhatsky
2018-03-05 20:45 ` Steven Rostedt
2018-03-06 2:00 ` Sergey Senozhatsky
2018-03-06 2:47 ` Steven Rostedt
2018-03-06 2:53 ` Sergey Senozhatsky [this message]
2018-03-06 3:16 ` Steven Rostedt
2018-03-06 8:10 ` Sergey Senozhatsky
2018-03-05 20:58 ` Steven Rostedt
2018-03-06 1:52 ` Sergey Senozhatsky
2018-03-06 2:43 ` Sergey Senozhatsky
2018-03-06 3:18 ` Steven Rostedt
2018-03-05 6:56 ` Qixuan.Wu
2018-03-05 13:29 ` Petr Mladek
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=20180306025350.GD6713@jagdpanzerIV \
--to=sergey.senozhatsky.work@gmail.com \
--cc=caijingxian@linux.alibaba.com \
--cc=chenggang.qin@linux.alibaba.com \
--cc=jack@suse.cz \
--cc=linux-kernel-owner@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pmladek@suse.com \
--cc=qixuan.wu@linux.alibaba.com \
--cc=rostedt@goodmis.org \
--cc=sergey.senozhatsky@gmail.com \
--cc=yuanliang.wyl@alibaba-inc.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