Re: [PATCH 1/4] fs/dcache: Limit numbers of negative dentries

2017-07-20 Thread Waiman Long
On 07/20/2017 11:08 AM, Miklos Szeredi wrote: > On Thu, Jul 20, 2017 at 4:21 PM, Waiman Long wrote: >> On 07/20/2017 03:20 AM, Miklos Szeredi wrote: >>> On Wed, Jul 19, 2017 at 10:42 PM, Waiman Long wrote: >> @@ -603,7 +698,13 @@ static struct dentry *dentry_kill(struct dentry >> *dentry

Re: [PATCH 1/4] fs/dcache: Limit numbers of negative dentries

2017-07-20 Thread Miklos Szeredi
On Thu, Jul 20, 2017 at 4:21 PM, Waiman Long wrote: > On 07/20/2017 03:20 AM, Miklos Szeredi wrote: >> On Wed, Jul 19, 2017 at 10:42 PM, Waiman Long wrote: >>> > @@ -603,7 +698,13 @@ static struct dentry *dentry_kill(struct dentry > *dentry) > > if (!IS_ROOT(dentry)) { >>

Re: [PATCH 1/4] fs/dcache: Limit numbers of negative dentries

2017-07-20 Thread Waiman Long
On 07/20/2017 03:20 AM, Miklos Szeredi wrote: > On Wed, Jul 19, 2017 at 10:42 PM, Waiman Long wrote: >> @@ -603,7 +698,13 @@ static struct dentry *dentry_kill(struct dentry *dentry) if (!IS_ROOT(dentry)) { parent = dentry->d_parent; -

Re: [PATCH 1/4] fs/dcache: Limit numbers of negative dentries

2017-07-20 Thread Miklos Szeredi
On Wed, Jul 19, 2017 at 10:42 PM, Waiman Long wrote: > On 07/19/2017 04:24 PM, Miklos Szeredi wrote: >> On Mon, Jul 17, 2017 at 3:39 PM, Waiman Long wrote: >>> The number of positive dentries is limited by the number of files >>> in the filesystems. The number of negative dentries, however, >>> h

Re: [PATCH 1/4] fs/dcache: Limit numbers of negative dentries

2017-07-19 Thread Waiman Long
On 07/19/2017 04:24 PM, Miklos Szeredi wrote: > On Mon, Jul 17, 2017 at 3:39 PM, Waiman Long wrote: >> The number of positive dentries is limited by the number of files >> in the filesystems. The number of negative dentries, however, >> has no limit other than the total amount of memory available

Re: [PATCH 1/4] fs/dcache: Limit numbers of negative dentries

2017-07-19 Thread Miklos Szeredi
On Mon, Jul 17, 2017 at 3:39 PM, Waiman Long wrote: > The number of positive dentries is limited by the number of files > in the filesystems. The number of negative dentries, however, > has no limit other than the total amount of memory available in > the system. So a rogue application that genera

Re: [PATCH 1/4] fs/dcache: Limit numbers of negative dentries

2017-07-19 Thread Waiman Long
On 07/19/2017 10:39 AM, Miklos Szeredi wrote: > On Mon, Jul 17, 2017 at 3:39 PM, Waiman Long wrote: >> The number of positive dentries is limited by the number of files >> in the filesystems. The number of negative dentries, however, >> has no limit other than the total amount of memory available

Re: [PATCH 1/4] fs/dcache: Limit numbers of negative dentries

2017-07-19 Thread Miklos Szeredi
On Mon, Jul 17, 2017 at 3:39 PM, Waiman Long wrote: > The number of positive dentries is limited by the number of files > in the filesystems. The number of negative dentries, however, > has no limit other than the total amount of memory available in > the system. So a rogue application that genera

Re: [PATCH 1/4] fs/dcache: Limit numbers of negative dentries

2017-07-17 Thread Waiman Long
On 07/17/2017 01:49 PM, Matthew Wilcox wrote: > On Mon, Jul 17, 2017 at 09:39:30AM -0400, Waiman Long wrote: >> The number of positive dentries is limited by the number of files >> in the filesystems. The number of negative dentries, however, >> has no limit other than the total amount of memory av

Re: [PATCH 1/4] fs/dcache: Limit numbers of negative dentries

2017-07-17 Thread Matthew Wilcox
On Mon, Jul 17, 2017 at 09:39:30AM -0400, Waiman Long wrote: > The number of positive dentries is limited by the number of files > in the filesystems. The number of negative dentries, however, > has no limit other than the total amount of memory available in > the system. So a rogue application tha

[PATCH 1/4] fs/dcache: Limit numbers of negative dentries

2017-07-17 Thread Waiman Long
The number of positive dentries is limited by the number of files in the filesystems. The number of negative dentries, however, has no limit other than the total amount of memory available in the system. So a rogue application that generates a lot of negative dentries can potentially exhaust most o