| Message ID | 20211102135422.121093-1-agruenba@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [GIT,PULL] gfs2: Fix mmap + page fault deadlocks | expand |
The pull request you sent on Tue, 2 Nov 2021 14:54:22 +0100:
> git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2.git tags/gfs2-v5.15-rc5-mmap-fault
has been merged into torvalds/linux.git:
https://git.kernel.org/torvalds/c/6edb6ba333d31bb42d9ab8b1b6ff1c5ecbc3813c
Thank you!
Hi Linus, please consider pulling these fixes for the gfs2 memory map + page fault deadlocks. Stephen Rothwell has pointed out the following merge conflict between commit: bb523b406c84 ("gup: Turn fault_in_pages_{readable,writeable} into fault_in_{readable,writeable}") from this patch set and the following two commits in your tree: fcfb7163329c ("x86/fpu/signal: Move xstate clearing out of copy_fpregs_to_sigframe()") a2a8fd9a3efd ("x86/fpu/signal: Change return code of restore_fpregs_from_user() to boolean") This is due to the fault_in_{pages_ =>}readable rename, and commit fcfb7163329c eliminating the call to fault_in_pages_writeable() from copy_fpstate_to_sigframe(). Stephen's conflict notification can be found here: https://lore.kernel.org/linux-next/20211015150420.617125bd@canb.auug.org.au/ Thanks, Andreas The following changes since commit 64570fbc14f8d7cb3fe3995f20e26bc25ce4b2cc: Linux 5.15-rc5 (2021-10-10 17:01:59 -0700) are available in the Git repository at: git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2.git tags/gfs2-v5.15-rc5-mmap-fault for you to fetch changes up to b01b2d72da25c000aeb124bc78daf3fb998be2b6: gfs2: Fix mmap + page fault deadlocks for direct I/O (2021-10-25 08:42:14 +0200) ---------------------------------------------------------------- gfs2: Fix mmap + page fault deadlocks Functions gfs2_file_read_iter and gfs2_file_write_iter are both accessing the user buffer to write to or read from while holding the inode glock. In the most basic scenario, that buffer will not be resident and it will be mapped to the same file. Accessing the buffer will trigger a page fault, and gfs2 will deadlock trying to take the same inode glock again while trying to handle that fault. Fix that and similar, more complex scenarios by disabling page faults while accessing user buffers. To make this work, introduce a small amount of new infrastructure and fix some bugs that didn't trigger so far, with page faults enabled. ---------------------------------------------------------------- Andreas Gruenbacher (16): iov_iter: Fix iov_iter_get_pages{,_alloc} page fault return value powerpc/kvm: Fix kvm_use_magic_page gup: Turn fault_in_pages_{readable,writeable} into fault_in_{readable,writeable} iov_iter: Turn iov_iter_fault_in_readable into fault_in_iov_iter_readable iov_iter: Introduce fault_in_iov_iter_writeable gfs2: Add wrapper for iomap_file_buffered_write gfs2: Clean up function may_grant gfs2: Move the inode glock locking to gfs2_file_buffered_write gfs2: Eliminate ip->i_gh gfs2: Fix mmap + page fault deadlocks for buffered I/O iomap: Fix iomap_dio_rw return value for user copies iomap: Support partial direct I/O on user copy failures iomap: Add done_before argument to iomap_dio_rw gup: Introduce FOLL_NOFAULT flag to disable page faults iov_iter: Introduce nofault flag to disable page faults gfs2: Fix mmap + page fault deadlocks for direct I/O Bob Peterson (1): gfs2: Introduce flag for glock holder auto-demotion arch/powerpc/kernel/kvm.c | 3 +- arch/powerpc/kernel/signal_32.c | 4 +- arch/powerpc/kernel/signal_64.c | 2 +- arch/x86/kernel/fpu/signal.c | 7 +- drivers/gpu/drm/armada/armada_gem.c | 7 +- fs/btrfs/file.c | 7 +- fs/btrfs/ioctl.c | 5 +- fs/erofs/data.c | 2 +- fs/ext4/file.c | 5 +- fs/f2fs/file.c | 2 +- fs/fuse/file.c | 2 +- fs/gfs2/bmap.c | 60 +------ fs/gfs2/file.c | 252 ++++++++++++++++++++++++--- fs/gfs2/glock.c | 330 +++++++++++++++++++++++++++--------- fs/gfs2/glock.h | 20 +++ fs/gfs2/incore.h | 4 +- fs/iomap/buffered-io.c | 2 +- fs/iomap/direct-io.c | 29 +++- fs/ntfs/file.c | 2 +- fs/ntfs3/file.c | 2 +- fs/xfs/xfs_file.c | 6 +- fs/zonefs/super.c | 4 +- include/linux/iomap.h | 11 +- include/linux/mm.h | 3 +- include/linux/pagemap.h | 58 +------ include/linux/uio.h | 4 +- lib/iov_iter.c | 103 ++++++++--- mm/filemap.c | 4 +- mm/gup.c | 139 ++++++++++++++- 29 files changed, 793 insertions(+), 286 deletions(-)