Re: [PATCH 0/8] netfs/cachefiles: Some bugfixes

[Gao Xiang]

Hi Zizhi,

On 2024/10/10 11:08, Zizhi Wo wrote:
> Hi!
>
> This patchset involves some general cachefiles workflows and the on-
> demand loading process. For example, the eighth patch fixes a memory
> ordering issue in cachefiles, and the fifth patch includes some cleanup.
> These all related to changes in the general cachefiles workflow, and I
> think these deserve some attention.
>
> Additionally, although the current EROFS on-demand loading mode based on
> cachefiles interaction might be considered for switching to the fanotify
> mode in the future, I believe the code based on the current cachefiles
> on-demand loading mode still requires maintenance. The first few patches
> here are bugfixes specifically for that.

Yes, I also agree with you.  I pinged David weeks ago, because many
bugfixes are not only impacted to cachefiles on-demand feature but
also generic cachefiles, hopefully they could be addressed upstream.

Thanks,
Gao Xiang

> Therefore, I would greatly appreciate it if anyone could take some time
> to review these patches. So friendly ping.
>
> Thanks,
> Zizhi Wo
>
>
> 在 2024/8/21 10:42, Zizhi Wo 写道:
> > Hi!
> >
> > We recently discovered some bugs through self-discovery and testing in
> > erofs ondemand loading mode, and this patchset is mainly used to fix
> > them. These patches are relatively simple changes, and I would be excited
> > to discuss them together with everyone. Below is a brief introduction to
> > each patch:
> >
> > Patch 1: Fix for wrong block_number calculated in ondemand write.
> >
> > Patch 2: Fix for wrong length return value in ondemand write.
> >
> > Patch 3: Fix missing position update in ondemand write, for scenarios
> > involving read-ahead, invoking the write syscall.
> >
> > Patch 4: Previously, the last redundant data was cleared during the umount
> > phase. This patch remove unnecessary data in advance.
> >
> > Patch 5: Code clean up for cachefiles_commit_tmpfile().
> >
> > Patch 6: Modify error return value in cachefiles_daemon_secctx().
> >
> > Patch 7: Fix object->file Null-pointer-dereference problem.
> >
> > Patch 8: Fix for memory out of order in fscache_create_volume().
> >
> >
> > Zizhi Wo (8):
> >    cachefiles: Fix incorrect block calculations in
> >      __cachefiles_prepare_write()
> >    cachefiles: Fix incorrect length return value in
> >      cachefiles_ondemand_fd_write_iter()
> >    cachefiles: Fix missing pos updates in
> >      cachefiles_ondemand_fd_write_iter()
> >    cachefiles: Clear invalid cache data in advance
> >    cachefiles: Clean up in cachefiles_commit_tmpfile()
> >    cachefiles: Modify inappropriate error return value in
> >      cachefiles_daemon_secctx()
> >    cachefiles: Fix NULL pointer dereference in object->file
> >    netfs/fscache: Add a memory barrier for FSCACHE_VOLUME_CREATING
> >
> >   fs/cachefiles/daemon.c    |  2 +-
> >   fs/cachefiles/interface.c |  3 +++
> >   fs/cachefiles/io.c        | 10 +++++-----
> >   fs/cachefiles/namei.c     | 23 +++++++++++++----------
> >   fs/cachefiles/ondemand.c  | 38 +++++++++++++++++++++++++++++---------
> >   fs/netfs/fscache_volume.c |  3 +--
> >   6 files changed, 52 insertions(+), 27 deletions(-)