6.13-stable review patch. If anyone has any objections, please let me know.
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From: Jens Axboe axboe@kernel.dk
[ Upstream commit a23ad06bfee5e51cd9e51aebf11401e7b4b5d00a ]
A previous commit changed all of the migration from the old to the new ring for resizing to use READ/WRITE_ONCE. However, ->sq_flags is an atomic_t, and while most archs won't complain on this, some will indeed flag this:
io_uring/register.c:554:9: sparse: sparse: cast to non-scalar io_uring/register.c:554:9: sparse: sparse: cast from non-scalar
Just use atomic_set/atomic_read for handling this case.
Reported-by: kernel test robot lkp@intel.com Closes: https://lore.kernel.org/oe-kbuild-all/202501242000.A2sKqaCL-lkp@intel.com/ Fixes: 2c5aae129f42 ("io_uring/register: document io_register_resize_rings() shared mem usage") Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- io_uring/register.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/io_uring/register.c b/io_uring/register.c index 371aec87e078c..14ece7754e4ca 100644 --- a/io_uring/register.c +++ b/io_uring/register.c @@ -553,7 +553,7 @@ static int io_register_resize_rings(struct io_ring_ctx *ctx, void __user *arg) ctx->cqe_cached = ctx->cqe_sentinel = NULL;
WRITE_ONCE(n.rings->sq_dropped, READ_ONCE(o.rings->sq_dropped)); - WRITE_ONCE(n.rings->sq_flags, READ_ONCE(o.rings->sq_flags)); + atomic_set(&n.rings->sq_flags, atomic_read(&o.rings->sq_flags)); WRITE_ONCE(n.rings->cq_flags, READ_ONCE(o.rings->cq_flags)); WRITE_ONCE(n.rings->cq_overflow, READ_ONCE(o.rings->cq_overflow));