On 8/14/24 3:46 PM, Hou Tao wrote: > Hi, > > On 8/14/2024 2:34 PM, Jingbo Xu wrote: >> Hi, Tao, >> >> On 4/26/24 10:39 PM, Hou Tao wrote: >>> From: Hou Tao <houtao1@xxxxxxxxxx> >>> >>> Hi, >>> >>> The patch set aims to fix the warning related to an abnormal size >>> parameter of kmalloc() in virtiofs. Patch #1 fixes it by introducing >>> use_pages_for_kvec_io option in fuse_conn and enabling it in virtiofs. >>> Beside the abnormal size parameter for kmalloc, the gfp parameter is >>> also questionable: GFP_ATOMIC is used even when the allocation occurs >>> in a kworker context. Patch #2 fixes it by using GFP_NOFS when the >>> allocation is initiated by the kworker. For more details, please check >>> the individual patches. >>> >>> As usual, comments are always welcome. >>> >>> Change Log: >>> >>> v3: >>> * introduce use_pages_for_kvec_io for virtiofs. When the option is >>> enabled, fuse will use iov_iter_extract_pages() to construct a page >>> array and pass the pages array instead of a pointer to virtiofs. >>> The benefit is twofold: the length of the data passed to virtiofs is >>> limited by max_pages, and there is no memory copy compared with v2. >>> >>> v2: https://lore.kernel.org/linux-fsdevel/20240228144126.2864064-1-houtao@xxxxxxxxxxxxxxx/ >>> * limit the length of ITER_KVEC dio by max_pages instead of the >>> newly-introduced max_nopage_rw. Using max_pages make the ITER_KVEC >>> dio being consistent with other rw operations. >>> * replace kmalloc-allocated bounce buffer by using a bounce buffer >>> backed by scattered pages when the length of the bounce buffer for >>> KVEC_ITER dio is larger than PAG_SIZE, so even on hosts with >>> fragmented memory, the KVEC_ITER dio can be handled normally by >>> virtiofs. (Bernd Schubert) >>> * merge the GFP_NOFS patch [1] into this patch-set and use >>> memalloc_nofs_{save|restore}+GFP_KERNEL instead of GFP_NOFS >>> (Benjamin Coddington) >>> >>> v1: https://lore.kernel.org/linux-fsdevel/20240103105929.1902658-1-houtao@xxxxxxxxxxxxxxx/ >>> >>> [1]: https://lore.kernel.org/linux-fsdevel/20240105105305.4052672-1-houtao@xxxxxxxxxxxxxxx/ >>> >>> Hou Tao (2): >>> virtiofs: use pages instead of pointer for kernel direct IO >>> virtiofs: use GFP_NOFS when enqueuing request through kworker >>> >>> fs/fuse/file.c | 12 ++++++++---- >>> fs/fuse/fuse_i.h | 3 +++ >>> fs/fuse/virtio_fs.c | 25 ++++++++++++++++--------- >>> 3 files changed, 27 insertions(+), 13 deletions(-) >>> >> We also encountered the same issue as [1] these days when attempting to >> insmod a module with ~6MB size, which is upon a virtiofs filesystem. >> >> It would be much helpful if this issue has a standard fix in the >> upstream. I see there will be v4 when reading through the mailing >> thread. Glad to know if there's any update to this series. > > Being busy with other stuff these days. I hope to send v4 before next > weekend. Many thanks, Tao. -- Thanks, Jingbo
