lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Thu, 21 Dec 2017 10:13:40 +1100
From:   NeilBrown <>
To:     Matthew Wilcox <>
Cc:     Al Viro <>,
        Linus Torvalds <>,
        "J. Bruce Fields" <>,
        Trond Myklebust <>,
        Anna Schumaker <>,,,
        Linux NFS Mailing List <>
Subject: Re: [PATCH/RFC] VFS: don't keep disconnected dentries on d_anon

On Wed, Dec 20 2017, Matthew Wilcox wrote:

> On Thu, Dec 21, 2017 at 09:45:40AM +1100, NeilBrown wrote:
>> -c/ Helper routines to allocate anonymous dentries, and to help attach
>> +   prefix.  If the refcount on a dentry with this flag set
>> +   becomes zero, the dentry is immediately discarded, rather than being
>> +   kept in the dcache.  If a dentry that is not already in the dcache
>> +   is repeatedly accessed by filehandle (as NFSD might do), an new dentry
>> +   will be a allocated for each access, and discarded at the end of
> s/a //
>> +   the access.  As there is no parent, children, or name in the dentry
>> +   is it unlikely that there will be any useful information to lose,
>> +   and allocating a new dentry should normally be fast.
> How about:
> As the dentry is completely unattached, there is little information to
> lose, and allocating a new dentry is normally fast.

Yes, that is less verbose, and probably just as informative.
Every time I rehearse this argument I wonder about d_fsdata.
I don't think it is actually relevant, but I feel that by not mentioning
it, I'm being dishonest...  Maybe I should think of it as being "less

Thanks - if this gets far enough to deserve a resent, I'll add those


Download attachment "signature.asc" of type "application/pgp-signature" (833 bytes)

Powered by blists - more mailing lists