| Message ID | f6953e5a-4183-8314-38f2-40be60998615@google.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [vfs.tmpfs] tmpfs,xattr: GFP_KERNEL_ACCOUNT for simple xattrs | expand |
On Mon 21-08-23 10:39:20, Hugh Dickins wrote: > It is particularly important for the userns mount case (when a sensible > nr_inodes maximum may not be enforced) that tmpfs user xattrs be subject > to memory cgroup limiting. Leave temporary buffer allocations as is, > but change the persistent simple xattr allocations from GFP_KERNEL to > GFP_KERNEL_ACCOUNT. This limits kernfs's cgroupfs too, but that's good. > > (I had intended to send this change earlier, but had been confused by > shmem_alloc_inode() using GFP_KERNEL, and thought a discussion would be > needed to change that too: no, I was forgetting the SLAB_ACCOUNT on that > kmem_cache, which implicitly adds __GFP_ACCOUNT to all its allocations.) > > Signed-off-by: Hugh Dickins <hughd@google.com> So I've checked and also kernfs is affected by these changes. I guess that makes sense as well. So feel free to add: Reviewed-by: Jan Kara <jack@suse.cz> Honza > --- > fs/xattr.c | 4 ++-- > mm/shmem.c | 2 +- > 2 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/fs/xattr.c b/fs/xattr.c > index 2d607542281b..efd4736bc94b 100644 > --- a/fs/xattr.c > +++ b/fs/xattr.c > @@ -1093,7 +1093,7 @@ struct simple_xattr *simple_xattr_alloc(const void *value, size_t size) > if (len < sizeof(*new_xattr)) > return NULL; > > - new_xattr = kvmalloc(len, GFP_KERNEL); > + new_xattr = kvmalloc(len, GFP_KERNEL_ACCOUNT); > if (!new_xattr) > return NULL; > > @@ -1217,7 +1217,7 @@ struct simple_xattr *simple_xattr_set(struct simple_xattrs *xattrs, > if (!new_xattr) > return ERR_PTR(-ENOMEM); > > - new_xattr->name = kstrdup(name, GFP_KERNEL); > + new_xattr->name = kstrdup(name, GFP_KERNEL_ACCOUNT); > if (!new_xattr->name) { > simple_xattr_free(new_xattr); > return ERR_PTR(-ENOMEM); > diff --git a/mm/shmem.c b/mm/shmem.c > index b782edeb69aa..11298c797cdc 100644 > --- a/mm/shmem.c > +++ b/mm/shmem.c > @@ -3616,7 +3616,7 @@ static int shmem_initxattrs(struct inode *inode, > > len = strlen(xattr->name) + 1; > new_xattr->name = kmalloc(XATTR_SECURITY_PREFIX_LEN + len, > - GFP_KERNEL); > + GFP_KERNEL_ACCOUNT); > if (!new_xattr->name) { > kvfree(new_xattr); > break; > -- > 2.35.3 >
On Mon, 21 Aug 2023 10:39:20 -0700, Hugh Dickins wrote: > It is particularly important for the userns mount case (when a sensible > nr_inodes maximum may not be enforced) that tmpfs user xattrs be subject > to memory cgroup limiting. Leave temporary buffer allocations as is, > but change the persistent simple xattr allocations from GFP_KERNEL to > GFP_KERNEL_ACCOUNT. This limits kernfs's cgroupfs too, but that's good. > > (I had intended to send this change earlier, but had been confused by > shmem_alloc_inode() using GFP_KERNEL, and thought a discussion would be > needed to change that too: no, I was forgetting the SLAB_ACCOUNT on that > kmem_cache, which implicitly adds __GFP_ACCOUNT to all its allocations.) > > [...] Applied to the vfs.tmpfs branch of the vfs/vfs.git tree. Patches in the vfs.tmpfs branch should appear in linux-next soon. Please report any outstanding bugs that were missed during review in a new review to the original patch series allowing us to drop it. It's encouraged to provide Acked-bys and Reviewed-bys even though the patch has now been applied. If possible patch trailers will be updated. Note that commit hashes shown below are subject to change due to rebase, trailer updates or similar. If in doubt, please check the listed branch. tree: https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git branch: vfs.tmpfs [1/1] tmpfs,xattr: GFP_KERNEL_ACCOUNT for simple xattrs https://git.kernel.org/vfs/vfs/c/572a3d1e5d3a
diff --git a/fs/xattr.c b/fs/xattr.c index 2d607542281b..efd4736bc94b 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -1093,7 +1093,7 @@ struct simple_xattr *simple_xattr_alloc(const void *value, size_t size) if (len < sizeof(*new_xattr)) return NULL; - new_xattr = kvmalloc(len, GFP_KERNEL); + new_xattr = kvmalloc(len, GFP_KERNEL_ACCOUNT); if (!new_xattr) return NULL; @@ -1217,7 +1217,7 @@ struct simple_xattr *simple_xattr_set(struct simple_xattrs *xattrs, if (!new_xattr) return ERR_PTR(-ENOMEM); - new_xattr->name = kstrdup(name, GFP_KERNEL); + new_xattr->name = kstrdup(name, GFP_KERNEL_ACCOUNT); if (!new_xattr->name) { simple_xattr_free(new_xattr); return ERR_PTR(-ENOMEM); diff --git a/mm/shmem.c b/mm/shmem.c index b782edeb69aa..11298c797cdc 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -3616,7 +3616,7 @@ static int shmem_initxattrs(struct inode *inode, len = strlen(xattr->name) + 1; new_xattr->name = kmalloc(XATTR_SECURITY_PREFIX_LEN + len, - GFP_KERNEL); + GFP_KERNEL_ACCOUNT); if (!new_xattr->name) { kvfree(new_xattr); break;
It is particularly important for the userns mount case (when a sensible nr_inodes maximum may not be enforced) that tmpfs user xattrs be subject to memory cgroup limiting. Leave temporary buffer allocations as is, but change the persistent simple xattr allocations from GFP_KERNEL to GFP_KERNEL_ACCOUNT. This limits kernfs's cgroupfs too, but that's good. (I had intended to send this change earlier, but had been confused by shmem_alloc_inode() using GFP_KERNEL, and thought a discussion would be needed to change that too: no, I was forgetting the SLAB_ACCOUNT on that kmem_cache, which implicitly adds __GFP_ACCOUNT to all its allocations.) Signed-off-by: Hugh Dickins <hughd@google.com> --- fs/xattr.c | 4 ++-- mm/shmem.c | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-)