linux-embedded.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Chris Brandt <Chris.Brandt@renesas.com>
To: Nicolas Pitre <nicolas.pitre@linaro.org>,
	Al Viro <viro@ZenIV.linux.org.uk>
Cc: "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
	"linux-embedded@vger.kernel.org" <linux-embedded@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH v2 4/5] cramfs: add mmap support
Date: Tue, 29 Aug 2017 19:38:03 +0000	[thread overview]
Message-ID: <SG2PR06MB1165FE414425AFD1C64E7CD78A9F0@SG2PR06MB1165.apcprd06.prod.outlook.com> (raw)
In-Reply-To: <nycvar.YSQ.7.76.1708281058590.2606@knanqh.ubzr>

On Monday, August 28, 2017, Nicolas Pitre wrote:
> OK I moved the lock promotion right at the beginning _before_ validating
> the split point. Also got a reference on the file to make sure that
> hasn't changed too.
> 
> > While we are at it, what happens if you mmap 120Kb, then munmap() the
> middle
> > 40Kb.  Leaving two 40Kb VMAs with 40Kb gap between them, that is.  Will
> your
> > ->vm_private_data be correct for both?
> 
> It wouldn't, but I now changed it to contain absolute values so now it
> will. And if the split point lands in the hole then the code just
> readjusts the pgoff at the beginning of the remaining part.
> 
> Here's the revised patch:


For whatever it's worth, as soon as I moved to 4.13-rc7,
CONFIG_CRAMFS_PHYSMEM=y crashes my XIP_KERNEL system before it can even 
get to any console output.

(both the old patch and the new patch)

If CONFIG_CRAMFS_PHYSMEM is not set, my XIP system boots fine.

However, if I boot -rc7 as a uImage, the new patch works just as good as
the old patch.

(mounting after boot, or booting with rootfstype=cramfs_physmem)


I guess I'll have to figure out what happened between -rc4 and -rc7.
Damn!


Chris


  reply	other threads:[~2017-08-29 19:38 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-16 17:35 [PATCH v2 0/5] cramfs refresh for embedded usage Nicolas Pitre
2017-08-16 17:35 ` [PATCH v2 1/5] cramfs: direct memory access support Nicolas Pitre
2017-08-16 18:28   ` Chris Brandt
2017-08-16 19:44     ` Nicolas Pitre
2017-08-16 17:35 ` [PATCH v2 2/5] cramfs: make cramfs_physmem usable as root fs Nicolas Pitre
2017-08-16 17:35 ` [PATCH v2 3/5] cramfs: implement uncompressed and arbitrary data block positioning Nicolas Pitre
2017-08-16 18:28   ` Chris Brandt
2017-08-16 17:35 ` [PATCH v2 4/5] cramfs: add mmap support Nicolas Pitre
2017-08-16 18:28   ` Chris Brandt
2017-08-28  6:46   ` Al Viro
2017-08-28 13:29     ` Nicolas Pitre
2017-08-28 14:23       ` Al Viro
2017-08-28 19:17         ` Nicolas Pitre
2017-08-29 19:38           ` Chris Brandt [this message]
2017-08-29 20:00             ` Nicolas Pitre
2017-08-29 20:11               ` Chris Brandt
2017-08-31  2:29               ` Chris Brandt
2017-08-16 17:35 ` [PATCH v2 5/5] cramfs: rehabilitate it Nicolas Pitre
2017-08-31  2:30 ` [PATCH v2 0/5] cramfs refresh for embedded usage Chris Brandt
2017-08-31  3:03   ` Nicolas Pitre

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=SG2PR06MB1165FE414425AFD1C64E7CD78A9F0@SG2PR06MB1165.apcprd06.prod.outlook.com \
    --to=chris.brandt@renesas.com \
    --cc=linux-embedded@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=nicolas.pitre@linaro.org \
    --cc=viro@ZenIV.linux.org.uk \
    /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 read-only IMAP folder(s) and NNTP newsgroup(s).