Merge tag 'linux-cpupower-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux

Merge cpupower utility updates for 6.18-rc1 from Shuah Khan:

"Fixes incorrect return vale in cpupower_write_sysfs() error path
 and passing incorrect size to cpuidle_state_write_file() while
 writing status to disable file in cpuidle_state_disable()."

* tag 'linux-cpupower-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux: (1125 commits)
  tools/cpupower: Fix incorrect size in cpuidle_state_disable()
  tools/cpupower: fix error return value in cpupower_write_sysfs()
  Linux 6.17-rc6
  MAINTAINERS: Input: Drop melfas-mip4 section
  USB: core: remove the move buf action
  MAINTAINERS: Update the DMA Rust entry
  erofs: fix long xattr name prefix placement
  Revert "net: usb: asix: ax88772: drop phylink use in PM to avoid MDIO runtime PM wakeups"
  hsr: hold rcu and dev lock for hsr_get_port_ndev
  hsr: use hsr_for_each_port_rtnl in hsr_port_get_hsr
  hsr: use rtnl lock when iterating over ports
  wifi: nl80211: completely disable per-link stats for now
  net: usb: asix: ax88772: drop phylink use in PM to avoid MDIO runtime PM wakeups
  net: ethtool: fix wrong type used in struct kernel_ethtool_ts_info
  selftests/bpf: Skip timer cases when bpf_timer is not supported
  bpf: Reject bpf_timer for PREEMPT_RT
  libceph: fix invalid accesses to ceph_connection_v1_info
  PM: hibernate: Restrict GFP mask in hibernation_snapshot()
  MAINTAINERS: add Phil as netfilter reviewer
  netfilter: nf_tables: restart set lookup on base_seq change
  ...

1 files changed, 18 insertions, 1 deletions

diff --git a/fs/btrfs/subpage.c b/fs/btrfs/subpage.c
index c9b3821957f7..cb4f97833dc3 100644
--- a/fs/btrfs/subpage.c
+++ b/fs/btrfs/subpage.c
@@ -448,8 +448,25 @@ void btrfs_subpage_set_writeback(const struct btrfs_fs_info *fs_info,
 
 	spin_lock_irqsave(&bfs->lock, flags);
 	bitmap_set(bfs->bitmaps, start_bit, len >> fs_info->sectorsize_bits);
+
+	/*
+	 * Don't clear the TOWRITE tag when starting writeback on a still-dirty
+	 * folio. Doing so can cause WB_SYNC_ALL writepages() to overlook it,
+	 * assume writeback is complete, and exit too early — violating sync
+	 * ordering guarantees.
+	 */
 	if (!folio_test_writeback(folio))
-		folio_start_writeback(folio);
+		__folio_start_writeback(folio, true);
+	if (!folio_test_dirty(folio)) {
+		struct address_space *mapping = folio_mapping(folio);
+		XA_STATE(xas, &mapping->i_pages, folio->index);
+		unsigned long flags;
+
+		xas_lock_irqsave(&xas, flags);
+		xas_load(&xas);
+		xas_clear_mark(&xas, PAGECACHE_TAG_TOWRITE);
+		xas_unlock_irqrestore(&xas, flags);
+	}
 	spin_unlock_irqrestore(&bfs->lock, flags);
 }