Re: [PATCH] iov_iter: fix copy_page_from_iter_atomic() if KMAP_LOCAL_FORCE_MAP

Christian Brauner
2024-10-28T12:41:14Z

On Sun, 27 Oct 2024 15:23:23 -0700, Hugh Dickins wrote:
> generic/077 on x86_32 CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP=y with highmem,
> on huge=always tmpfs, issues a warning and then hangs (interruptibly):
>
> WARNING: CPU: 5 PID: 3517 at mm/highmem.c:622 kunmap_local_indexed+0x62/0xc9
> CPU: 5 UID: 0 PID: 3517 Comm: cp Not tainted 6.12.0-rc4 #2
> ...
> copy_page_from_iter_atomic+0xa6/0x5ec
> generic_perform_write+0xf6/0x1b4
> shmem_file_write_iter+0x54/0x67
>
> [...]

Applied to the vfs.fixes branch of the vfs/vfs.git tree.
Patches in the vfs.fixes 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.fixes

[1/1] iov_iter: fix copy_page_from_iter_atomic() if KMAP_LOCAL_FORCE_MAP