Merge branch 'for-5.10/core' into for-linus

- nonblocking read semantics fix for hid-debug

1 files changed, 10 insertions, 1 deletions

diff --git a/fs/buffer.c b/fs/buffer.c
index 061dd202979d..50bbc99e3d96 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -1958,7 +1958,7 @@ iomap_to_bh(struct inode *inode, sector_t block, struct buffer_head *bh,
 		 */
 		set_buffer_new(bh);
 		set_buffer_unwritten(bh);
-		/* FALLTHRU */
+		fallthrough;
 	case IOMAP_MAPPED:
 		if ((iomap->flags & IOMAP_F_NEW) ||
 		    offset >= i_size_read(inode))
@@ -3157,6 +3157,15 @@ int __sync_dirty_buffer(struct buffer_head *bh, int op_flags)
 	WARN_ON(atomic_read(&bh->b_count) < 1);
 	lock_buffer(bh);
 	if (test_clear_buffer_dirty(bh)) {
+		/*
+		 * The bh should be mapped, but it might not be if the
+		 * device was hot-removed. Not much we can do but fail the I/O.
+		 */
+		if (!buffer_mapped(bh)) {
+			unlock_buffer(bh);
+			return -EIO;
+		}
+
 		get_bh(bh);
 		bh->b_end_io = end_buffer_write_sync;
 		ret = submit_bh(REQ_OP_WRITE, op_flags, bh);