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Y . Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Long Li , Alexander Shishkin , Maxime Coquelin , Alexandre Torgue , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Bodo Stroesser , "Martin K . Petersen" , David Howells , Marc Dionne , Alexander Viro , Christian Brauner , Jan Kara , David Hildenbrand , "Liam R . Howlett" , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jann Horn , Pedro Falcato , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-mtd@lists.infradead.org, linux-staging@lists.linux.dev, linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, linux-afs@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Ryan Roberts References: <08804c94e39d9102a3a8fbd12385e8aa079ba1d3.1774045440.git.ljs@kernel.org> From: "Vlastimil Babka (SUSE)" In-Reply-To: <08804c94e39d9102a3a8fbd12385e8aa079ba1d3.1774045440.git.ljs@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 11F211A0016 X-Stat-Signature: 7rsht9e7dqo5qgji1n59qjweo3gok9pn X-Rspam-User: X-HE-Tag: 1774429585-730787 X-HE-Meta: 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 SPaxhEK/ d2k+2R472So69vqD79DPGtnH016QLGWUk/LI0wooM/j0tcEi6E4AHTytJeR2Uc9gt2u9XdoIqiA1Byg6UIlIXQ3txhCs6Yq+fy+wqqK7L4/TJ3T+X4YnbgsWjI/uD0I+1SYP2T9V+T6p5DHc/rmrBa/FOhHNpJ9m26PQj/0dD60N2nMokr7Dtar0giT3knnpOW+rzgUK5g0WZJHqAWFsno17qJPFiDTt2tn+pBrWFpKmeb/sAnS2In41UUXIEwwQMjn9R+4L8zzBb/h1wH1fwPsLgvheHSzsd9x5YixRoFEGq1mPLlaKh9882zVyIwd2V9tGQumWr4w7wSh4Cu7Hqh4FvFosvL/z01nSnr8Mw+zjRM6bjqfCFQQm7MTKxdqyeMog8ieAGqm33GPahJFPqdOhKvmZFhDdG2PjzRwr1HLazgaB9u+8zUgIM2g== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 3/20/26 23:39, Lorenzo Stoakes (Oracle) wrote: > Partially reverts commit 9d5403b1036c ("fs: convert most other > generic_file_*mmap() users to .mmap_prepare()"). > > This is because the .mmap invocation establishes a refcount, but > .mmap_prepare is called at a point where a merge or an allocation failure > might happen after the call, which would leak the refcount increment. > > Functionality is being added to permit the use of .mmap_prepare in this > case, but in the interim, we need to fix this. > > Fixes: 9d5403b1036c ("fs: convert most other generic_file_*mmap() users to .mmap_prepare()") > Cc: > Signed-off-by: Lorenzo Stoakes (Oracle) Acked-by: Vlastimil Babka (SUSE) > --- > fs/afs/file.c | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-) > > diff --git a/fs/afs/file.c b/fs/afs/file.c > index f609366fd2ac..74d04af51ff4 100644 > --- a/fs/afs/file.c > +++ b/fs/afs/file.c > @@ -19,7 +19,7 @@ > #include > #include "internal.h" > > -static int afs_file_mmap_prepare(struct vm_area_desc *desc); > +static int afs_file_mmap(struct file *file, struct vm_area_struct *vma); > > static ssize_t afs_file_read_iter(struct kiocb *iocb, struct iov_iter *iter); > static ssize_t afs_file_splice_read(struct file *in, loff_t *ppos, > @@ -35,7 +35,7 @@ const struct file_operations afs_file_operations = { > .llseek = generic_file_llseek, > .read_iter = afs_file_read_iter, > .write_iter = netfs_file_write_iter, > - .mmap_prepare = afs_file_mmap_prepare, > + .mmap = afs_file_mmap, > .splice_read = afs_file_splice_read, > .splice_write = iter_file_splice_write, > .fsync = afs_fsync, > @@ -492,16 +492,16 @@ static void afs_drop_open_mmap(struct afs_vnode *vnode) > /* > * Handle setting up a memory mapping on an AFS file. > */ > -static int afs_file_mmap_prepare(struct vm_area_desc *desc) > +static int afs_file_mmap(struct file *file, struct vm_area_struct *vma) > { > - struct afs_vnode *vnode = AFS_FS_I(file_inode(desc->file)); > + struct afs_vnode *vnode = AFS_FS_I(file_inode(file)); > int ret; > > afs_add_open_mmap(vnode); > > - ret = generic_file_mmap_prepare(desc); > + ret = generic_file_mmap(file, vma); > if (ret == 0) > - desc->vm_ops = &afs_vm_ops; > + vma->vm_ops = &afs_vm_ops; > else > afs_drop_open_mmap(vnode); > return ret;