Commit cbcf7214 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: return locked and pinned page accounting 



Locked and pinned memory accounting in io_{,un}account_mem() depends on
having ->sqo_mm, which is NULL after a recent change for non SQPOLL'ed
io_ring. That disables the accounting.

Return ->sqo_mm initialisation back, and do __io_sq_thread_acquire_mm()
based on IORING_SETUP_SQPOLL flag.

Fixes: 8eb06d7e ("io_uring: fix missing ->mm on exit")
Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 5dbcad51

fs/io_uring.c

+5 −4
Original line number Original line Diff line number Diff line
@@ -981,7 +981,8 @@ static void io_sq_thread_drop_mm(void) 
static int __io_sq_thread_acquire_mm(struct io_ring_ctx *ctx)

static int __io_sq_thread_acquire_mm(struct io_ring_ctx *ctx)

{

{

	if (!current->mm) {

	if (!current->mm) {

		if (unlikely(!ctx->sqo_mm || !mmget_not_zero(ctx->sqo_mm)))

		if (unlikely(!(ctx->flags & IORING_SETUP_SQPOLL) ||

			     !mmget_not_zero(ctx->sqo_mm)))

			return -EFAULT;

			return -EFAULT;

		kthread_use_mm(ctx->sqo_mm);

		kthread_use_mm(ctx->sqo_mm);

	}

	}
@@ -7259,10 +7260,10 @@ static int io_sq_offload_start(struct io_ring_ctx *ctx, 
{

{

	int ret;

	int ret;





	if (ctx->flags & IORING_SETUP_SQPOLL) {

	mmgrab(current->mm);

	mmgrab(current->mm);

	ctx->sqo_mm = current->mm;

	ctx->sqo_mm = current->mm;





	if (ctx->flags & IORING_SETUP_SQPOLL) {

		ret = -EPERM;

		ret = -EPERM;

		if (!capable(CAP_SYS_ADMIN))

		if (!capable(CAP_SYS_ADMIN))

			goto err;

			goto err;