From: Kees Cook <keescook@chromium.org>
To: Yuxiao Zhang <yuxiaozhang@google.com>
Cc: Tony Luck <tony.luck@intel.com>,
"'Guilherme G . Piccoli'" <gpiccoli@igalia.com>,
Greg KH <gregkh@linuxfoundation.org>,
linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org,
wak@google.com
Subject: Re: [PATCH] pstore: ramoops: support pmsg size larger than kmalloc limitation
Date: Wed, 28 Jun 2023 10:55:58 -0700 [thread overview]
Message-ID: <202306281053.EC5115465B@keescook> (raw)
In-Reply-To: <20230627202540.881909-2-yuxiaozhang@google.com>
On Tue, Jun 27, 2023 at 01:25:41PM -0700, Yuxiao Zhang wrote:
> Current pmsg implementation is using kmalloc for pmsg record buffer,
> which has max size limits based on page size. Currently even we
> allocate enough space with pmsg-size, pmsg will still fail if the
> file size is larger than what kmalloc allowed.
>
> Since we don't need physical contiguous memory for pmsg buffer
> , we can use kvmalloc to avoid such limitation.
Conceptually, I am fine with this change. I need a little time to trace
down the allocations. At first glance, I thought this patch only needed
to cover pstore_write_user_compat(), but I guess the read side needs to
be adjusted as well?
I'll double-check.
And yes, Greg's questions are all good -- fixing syntax and adding size
details in the commit log would be appreciated.
-Kees
--
Kees Cook
next prev parent reply other threads:[~2023-06-28 17:56 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-27 20:25 [PATCH] pstore: ramoops: support pmsg size larger than kmalloc limitation Yuxiao Zhang
2023-06-28 5:30 ` Greg KH
2023-06-28 17:10 ` Yuxiao Zhang
2023-06-28 18:12 ` Guilherme G. Piccoli
2023-06-28 23:24 ` Kees Cook
2023-06-29 19:22 ` Guilherme G. Piccoli
2023-06-28 17:55 ` Kees Cook [this message]
2023-06-30 20:50 ` Yuxiao Zhang
2023-06-30 20:53 ` Yuxiao Zhang
2023-07-18 20:23 ` Yuxiao Zhang
2023-08-17 23:40 ` Kees Cook
-- strict thread matches above, loose matches on Subject: below --
2022-01-04 19:36 pstore/ramoops - why only collect a partial dmesg? Guilherme G. Piccoli
2023-06-28 18:48 ` [PATCH] pstore: ramoops: support pmsg size larger than kmalloc limitation Yuxiao Zhang
2023-06-28 19:05 ` Guilherme G. Piccoli
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=202306281053.EC5115465B@keescook \
--to=keescook@chromium.org \
--cc=gpiccoli@igalia.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-hardening@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=tony.luck@intel.com \
--cc=wak@google.com \
--cc=yuxiaozhang@google.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.