From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Kees Cook <keescook@chromium.org>,
Thomas Gleixner <tglx@linutronix.de>,
Borislav Petkov <bp@alien8.de>,
linux-efi <linux-efi@vger.kernel.org>,
Ard Biesheuvel <ard.biesheuvel@linaro.org>,
Anton Vorontsov <anton@enomsg.org>,
Colin Cross <ccross@android.com>, Tony Luck <tony.luck@intel.com>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] pstore: Convert buf_lock to semaphore
Date: Mon, 3 Dec 2018 12:18:29 +0100 [thread overview]
Message-ID: <20181203111826.ri2csbxs33j34dvo@linutronix.de> (raw)
In-Reply-To: <CAK8P3a3xUMnWrSsW6gNwc5y0z-wR23v8Q6TGH+yNpDJq65FeMw@mail.gmail.com>
On 2018-12-01 09:42:38 [+0100], Arnd Bergmann wrote:
> You are right that you can't take (or release) a mutex from interrupt
> context. However, I don't think converting a spinlock to a semaphore
> is going to help here either.
you can acquire a semaphore with a try_lock from interrupts context but
you can't do that with a mutex. You can also a acquire a semaphore in
one context and release in another. Not that I'm a fan of those things
but those two are often the reasons why people stick with a semaphore.
I haven't looked a general picture yet, will try to do so later today or
tomorrow.
> Arnd
Sebastian
next prev parent reply other threads:[~2018-12-03 11:18 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-30 22:47 Kees Cook
2018-11-30 22:51 ` Arnd Bergmann
2018-12-01 2:42 ` Kees Cook
2018-12-01 8:42 ` Arnd Bergmann
2018-12-03 11:18 ` Sebastian Andrzej Siewior [this message]
2018-12-03 16:26 ` Arnd Bergmann
2018-12-04 0:28 ` Kees Cook
2018-12-04 15:40 ` Sebastian Andrzej Siewior
2018-12-04 16:17 ` Kees Cook
2018-12-04 17:23 ` Kees Cook
2018-12-04 18:06 ` Sebastian Andrzej Siewior
2018-12-21 15:37 ` Ard Biesheuvel
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=20181203111826.ri2csbxs33j34dvo@linutronix.de \
--to=bigeasy@linutronix.de \
--cc=anton@enomsg.org \
--cc=ard.biesheuvel@linaro.org \
--cc=arnd@arndb.de \
--cc=bp@alien8.de \
--cc=ccross@android.com \
--cc=keescook@chromium.org \
--cc=linux-efi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=tglx@linutronix.de \
--cc=tony.luck@intel.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
all inboxes | Powered by JetHome®