[PATCH net-next 1/2] rxrpc: Fix use of changed alignment param to page_frag_alloc_align()

From: David Howells
Date: Tue Mar 12 2024 - 19:37:56 EST


Commit 411c5f36805c ("mm/page_alloc: modify page_frag_alloc_align() to
accept align as an argument") changed the way page_frag_alloc_align()
worked, but it didn't fix AF_RXRPC as that use of that allocator function
hadn't been merged yet at the time. Now, when the AFS filesystem is used,
this results in:

WARNING: CPU: 4 PID: 379 at include/linux/gfp.h:323 rxrpc_alloc_data_txbuf+0x9d/0x2b0 [rxrpc]

Fix this by using __page_frag_alloc_align() instead.

Note that it might be better to use an order-based alignment rather than a
mask-based alignment.

Fixes: 49489bb03a50 ("rxrpc: Do zerocopy using MSG_SPLICE_PAGES and page frags")
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Reported-by: Marc Dionne <marc.dionne@xxxxxxxxxxxx>
cc: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
cc: Alexander Duyck <alexander.duyck@xxxxxxxxx>
cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
cc: Eric Dumazet <edumazet@xxxxxxxxxx>
cc: Jakub Kicinski <kuba@xxxxxxxxxx>
cc: Paolo Abeni <pabeni@xxxxxxxxxx>
cc: linux-afs@xxxxxxxxxxxxxxxxxxx
cc: netdev@xxxxxxxxxxxxxxx
---
net/rxrpc/txbuf.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/rxrpc/txbuf.c b/net/rxrpc/txbuf.c
index b2a82ab756c2..e0679658d9de 100644
--- a/net/rxrpc/txbuf.c
+++ b/net/rxrpc/txbuf.c
@@ -33,8 +33,8 @@ struct rxrpc_txbuf *rxrpc_alloc_data_txbuf(struct rxrpc_call *call, size_t data_
total = hoff + sizeof(*whdr) + data_size;

mutex_lock(&call->conn->tx_data_alloc_lock);
- buf = page_frag_alloc_align(&call->conn->tx_data_alloc, total, gfp,
- ~(data_align - 1) & ~(L1_CACHE_BYTES - 1));
+ buf = __page_frag_alloc_align(&call->conn->tx_data_alloc, total, gfp,
+ ~(data_align - 1) & ~(L1_CACHE_BYTES - 1));
mutex_unlock(&call->conn->tx_data_alloc_lock);
if (!buf) {
kfree(txb);