From: Al Viro <viro@zeniv.linux.org.uk>
To: Christoph Hellwig <hch@infradead.org>
Cc: Qian Cai <cai@lca.pw>,
linux-fsdevel@vger.kernel.org,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: "fs/namei.c: keep track of nd->root refcount status" causes boot panic
Date: Tue, 3 Sep 2019 14:48:32 +0100 [thread overview]
Message-ID: <20190903134832.GH1131@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20190903130456.GA9567@infradead.org>
On Tue, Sep 03, 2019 at 06:04:56AM -0700, Christoph Hellwig wrote:
> On Tue, Sep 03, 2019 at 01:37:19PM +0100, Al Viro wrote:
> > On Tue, Sep 03, 2019 at 12:21:36AM -0400, Qian Cai wrote:
> > > The linux-next commit "fs/namei.c: keep track of nd->root refcount status” [1] causes boot panic on all
> > > architectures here on today’s linux-next (0902). Reverted it will fix the issue.
> >
> > <swearing>
> >
> > OK, I see what's going on. Incremental to be folded in:
> >
> > diff --git a/include/linux/namei.h b/include/linux/namei.h
> > index 20ce2f917ef4..2ed0942a67f8 100644
> > --- a/include/linux/namei.h
> > +++ b/include/linux/namei.h
> > @@ -20,8 +20,8 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT, LAST_BIND};
> > #define LOOKUP_FOLLOW 0x0001 /* follow links at the end */
> > #define LOOKUP_DIRECTORY 0x0002 /* require a directory */
> > #define LOOKUP_AUTOMOUNT 0x0004 /* force terminal automount */
> > -#define LOOKUP_EMPTY 0x4000 /* accept empty path [user_... only] */
> > -#define LOOKUP_DOWN 0x8000 /* follow mounts in the starting point */
> > +#define LOOKUP_EMPTY 0x8000 /* accept empty path [user_... only] */
> > +#define LOOKUP_DOWN 0x10000 /* follow mounts in the starting point */
> >
> > #define LOOKUP_REVAL 0x0020 /* tell ->d_revalidate() to trust no cache */
> > #define LOOKUP_RCU 0x0040 /* RCU pathwalk mode; semi-internal */
>
> Any chance to keep these ordered numerically to avoid someone else
> introdcing this kind of bug again later on?
Not sure what would be the best way to do it... I don't mind breaking
the out-of-tree modules, whatever their license is; what I would rather
avoid is _quiet_ breaking of such.
next prev parent reply other threads:[~2019-09-03 13:48 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-03 4:21 "fs/namei.c: keep track of nd->root refcount status" causes boot panic Qian Cai
2019-09-03 5:22 ` Dexuan-Linux Cui
2019-09-03 5:50 ` Dexuan Cui
2019-09-03 6:00 ` Dexuan Cui
2019-09-03 8:13 ` Naresh Kamboju
2019-09-03 9:08 ` Sachin Sant
2019-09-03 12:37 ` Al Viro
2019-09-03 13:04 ` Christoph Hellwig
2019-09-03 13:48 ` Al Viro [this message]
2019-09-03 13:50 ` Christoph Hellwig
2019-09-03 13:53 ` Al Viro
2019-09-03 15:39 ` Christoph Hellwig
2019-09-03 17:56 ` Al Viro
2019-09-04 12:39 ` Christoph Hellwig
2019-09-05 9:13 ` Naresh Kamboju
2019-09-05 16:46 ` Al Viro
2019-09-05 12:17 ` Kevin Easton
2019-09-03 21:30 ` Theodore Y. Ts'o
2019-09-03 13:31 ` Al Viro
2019-09-03 13:52 ` Naresh Kamboju
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=20190903134832.GH1131@ZenIV.linux.org.uk \
--to=viro@zeniv.linux.org.uk \
--cc=cai@lca.pw \
--cc=hch@infradead.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.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).