The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x ffec85d53d0f39ee4680a2cf0795255e000e1feb # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '167870452211436@kroah.com' --subject-prefix 'PATCH 5.4.y' HEAD^..

Possible dependencies:

ffec85d53d0f ("ext4: fix cgroup writeback accounting with fs-layer encryption") 29b83c574b0a ("ext4: remove nr_submitted from ext4_bio_write_page()") 04e568a3b31c ("ext4: handle redirtying in ext4_bio_write_page()") c75e707fe1aa ("block: remove the per-bio/request write hint") 4c4dad11ff85 ("ext4: pass the operation to bio_alloc") 07888c665b40 ("block: pass a block_device and opf to bio_alloc") b77c88c2100c ("block: pass a block_device and opf to bio_alloc_kiocb") 609be1066731 ("block: pass a block_device and opf to bio_alloc_bioset") 0a3140ea0fae ("block: pass a block_device and opf to blk_next_bio") 3b005bf6acf0 ("block: move blk_next_bio to bio.c") 7d8d0c658d48 ("xen-blkback: bio_alloc can't fail if it is allow to sleep") d7b78de2b155 ("rnbd-srv: remove struct rnbd_dev_blk_io") 1fe0640ff94f ("rnbd-srv: simplify bio mapping in process_rdma") 4b1dc86d1857 ("drbd: bio_alloc can't fail if it is allow to sleep") 3f868c09ea8f ("dm-crypt: remove clone_init") 53db984e004c ("dm: bio_alloc can't fail if it is allowed to sleep") 39146b6f66ba ("ntfs3: remove ntfs_alloc_bio") 5d2ca2132f88 ("nfs/blocklayout: remove bl_alloc_init_bio") f0d911927b3c ("nilfs2: remove nilfs_alloc_seg_bio") d5f68a42da7a ("fs: remove mpage_alloc")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From ffec85d53d0f39ee4680a2cf0795255e000e1feb Mon Sep 17 00:00:00 2001 From: Eric Biggers ebiggers@google.com Date: Thu, 2 Feb 2023 16:55:03 -0800 Subject: [PATCH] ext4: fix cgroup writeback accounting with fs-layer encryption

When writing a page from an encrypted file that is using filesystem-layer encryption (not inline encryption), ext4 encrypts the pagecache page into a bounce page, then writes the bounce page.

It also passes the bounce page to wbc_account_cgroup_owner(). That's incorrect, because the bounce page is a newly allocated temporary page that doesn't have the memory cgroup of the original pagecache page. This makes wbc_account_cgroup_owner() not account the I/O to the owner of the pagecache page as it should.

Fix this by always passing the pagecache page to wbc_account_cgroup_owner().

Fixes: 001e4a8775f6 ("ext4: implement cgroup writeback support") Cc: stable@vger.kernel.org Reported-by: Matthew Wilcox (Oracle) willy@infradead.org Signed-off-by: Eric Biggers ebiggers@google.com Acked-by: Tejun Heo tj@kernel.org Link: https://lore.kernel.org/r/20230203005503.141557-1-ebiggers@kernel.org Signed-off-by: Theodore Ts'o tytso@mit.edu

diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c index beaec6d81074..1e4db96a04e6 100644 --- a/fs/ext4/page-io.c +++ b/fs/ext4/page-io.c @@ -409,7 +409,8 @@ static void io_submit_init_bio(struct ext4_io_submit *io,

static void io_submit_add_bh(struct ext4_io_submit *io, struct inode *inode, - struct page *page, + struct page *pagecache_page, + struct page *bounce_page, struct buffer_head *bh) { int ret; @@ -421,10 +422,11 @@ static void io_submit_add_bh(struct ext4_io_submit *io, } if (io->io_bio == NULL) io_submit_init_bio(io, bh); - ret = bio_add_page(io->io_bio, page, bh->b_size, bh_offset(bh)); + ret = bio_add_page(io->io_bio, bounce_page ?: pagecache_page, + bh->b_size, bh_offset(bh)); if (ret != bh->b_size) goto submit_and_retry; - wbc_account_cgroup_owner(io->io_wbc, page, bh->b_size); + wbc_account_cgroup_owner(io->io_wbc, pagecache_page, bh->b_size); io->io_next_block++; }

@@ -561,8 +563,7 @@ int ext4_bio_write_page(struct ext4_io_submit *io, do { if (!buffer_async_write(bh)) continue; - io_submit_add_bh(io, inode, - bounce_page ? bounce_page : page, bh); + io_submit_add_bh(io, inode, page, bounce_page, bh); } while ((bh = bh->b_this_page) != head); unlock: unlock_page(page);