From: "Theodore Y. Ts'o" <tytso@mit.edu>
To: Qian Cai <cai@lca.pw>
Cc: pmladek@suse.com, sergey.senozhatsky.work@gmail.com,
arnd@arndb.de, peterz@infradead.org, catalin.marinas@arm.com,
linux-kernel@vger.kernel.org, rostedt@goodmis.org,
linux-mm@kvack.org, gregkh@linuxfoundation.org,
longman@redhat.com, dan.j.williams@intel.com, will@kernel.org,
tglx@linutronix.de, linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] char/random: silence a lockdep splat with printk()
Date: Tue, 7 Jan 2020 16:07:24 -0500 [thread overview]
Message-ID: <20200107210724.GN3619@mit.edu> (raw)
In-Reply-To: <1573679785-21068-1-git-send-email-cai@lca.pw>
On Wed, Nov 13, 2019 at 04:16:25PM -0500, Qian Cai wrote:
> From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
>
> Sergey didn't like the locking order,
>
> uart_port->lock -> tty_port->lock
>
> uart_write (uart_port->lock)
> __uart_start
> pl011_start_tx
> pl011_tx_chars
> uart_write_wakeup
> tty_port_tty_wakeup
> tty_port_default
> tty_port_tty_get (tty_port->lock)
>
> but those code is so old, and I have no clue how to de-couple it after
> checking other locks in the splat. There is an onging effort to make all
> printk() as deferred, so until that happens, workaround it for now as a
> short-term fix.
Applied, thanks.
- Ted
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2020-01-07 21:08 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-13 21:16 [PATCH] char/random: silence a lockdep splat with printk() Qian Cai
2019-12-03 18:46 ` Qian Cai
2019-12-05 1:00 ` Sergey Senozhatsky
2019-12-17 1:52 ` Qian Cai
2020-01-02 15:42 ` Qian Cai
2020-01-02 17:07 ` Steven Rostedt
2020-01-02 17:16 ` Qian Cai
2020-01-02 18:00 ` Theodore Y. Ts'o
2020-01-07 21:07 ` Theodore Y. Ts'o [this message]
2020-03-24 15:13 ` dmesg -w regression in v5.4.22, bisected, was: " Zygo Blaxell
2020-03-25 2:35 ` Sergey Senozhatsky
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=20200107210724.GN3619@mit.edu \
--to=tytso@mit.edu \
--cc=arnd@arndb.de \
--cc=cai@lca.pw \
--cc=catalin.marinas@arm.com \
--cc=dan.j.williams@intel.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=longman@redhat.com \
--cc=peterz@infradead.org \
--cc=pmladek@suse.com \
--cc=rostedt@goodmis.org \
--cc=sergey.senozhatsky.work@gmail.com \
--cc=tglx@linutronix.de \
--cc=will@kernel.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).