The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y git checkout FETCH_HEAD git cherry-pick -x e56d4b633fffea9510db468085bed0799cba4ecd # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2024061852-peroxide-reverb-11a5@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..

Possible dependencies:

e56d4b633fff ("nbd: Fix signal handling") 2a6751e052ab ("nbd: Improve the documentation of the locking assumptions") 3123ac779233 ("nbd: factor out a helper to get nbd_config without holding 'config_lock'") 1b59860540a4 ("nbd: fold nbd config initialization into nbd_alloc_config()") d32e2bf83791 ("block: pass a gendisk to ->open") 444aa2c58cb3 ("block: pass a gendisk on bdev_check_media_change") 48a905198024 ("ublk_drv: only allow owner to open unprivileged disk") 4093cb5a0634 ("ublk_drv: add mechanism for supporting unprivileged ublk device") bfbcef036396 ("ublk_drv: move ublk_get_device_from_id into ublk_ctrl_uring_cmd") 4b83e99ee709 ("Revert "pktcdvd: remove driver."") ce8a79d5601a ("Merge tag 'for-6.2/block-2022-12-08' of git://git.kernel.dk/linux")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From e56d4b633fffea9510db468085bed0799cba4ecd Mon Sep 17 00:00:00 2001 From: Bart Van Assche bvanassche@acm.org Date: Fri, 10 May 2024 13:23:13 -0700 Subject: [PATCH] nbd: Fix signal handling

Both nbd_send_cmd() and nbd_handle_cmd() return either a negative error number or a positive blk_status_t value. nbd_queue_rq() converts these return values into a blk_status_t value. There is a bug in the conversion code: if nbd_send_cmd() returns BLK_STS_RESOURCE, nbd_queue_rq() should return BLK_STS_RESOURCE instead of BLK_STS_OK. Fix this, move the conversion code into nbd_handle_cmd() and fix the remaining sparse warnings.

This patch fixes the following sparse warnings:

drivers/block/nbd.c:673:32: warning: incorrect type in return expression (different base types) drivers/block/nbd.c:673:32: expected int drivers/block/nbd.c:673:32: got restricted blk_status_t [usertype] drivers/block/nbd.c:714:48: warning: incorrect type in return expression (different base types) drivers/block/nbd.c:714:48: expected int drivers/block/nbd.c:714:48: got restricted blk_status_t [usertype] drivers/block/nbd.c:1120:21: warning: incorrect type in assignment (different base types) drivers/block/nbd.c:1120:21: expected int [assigned] ret drivers/block/nbd.c:1120:21: got restricted blk_status_t [usertype] drivers/block/nbd.c:1125:16: warning: incorrect type in return expression (different base types) drivers/block/nbd.c:1125:16: expected restricted blk_status_t drivers/block/nbd.c:1125:16: got int [assigned] ret

Cc: Christoph Hellwig hch@lst.de Cc: Josef Bacik jbacik@fb.com Cc: Yu Kuai yukuai3@huawei.com Cc: Markus Pargmann mpa@pengutronix.de Fixes: fc17b6534eb8 ("blk-mq: switch ->queue_rq return value to blk_status_t") Cc: stable@vger.kernel.org Signed-off-by: Bart Van Assche bvanassche@acm.org Link: https://lore.kernel.org/r/20240510202313.25209-6-bvanassche@acm.org Signed-off-by: Jens Axboe axboe@kernel.dk

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 29e43ab1650c..22a79a62cc4e 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -588,6 +588,10 @@ static inline int was_interrupted(int result) return result == -ERESTARTSYS || result == -EINTR; }

+/* + * Returns BLK_STS_RESOURCE if the caller should retry after a delay. Returns + * -EAGAIN if the caller should requeue @cmd. Returns -EIO if sending failed. + */ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index) { struct request *req = blk_mq_rq_from_pdu(cmd); @@ -670,7 +674,7 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index) nsock->sent = sent; } set_bit(NBD_CMD_REQUEUED, &cmd->flags); - return BLK_STS_RESOURCE; + return (__force int)BLK_STS_RESOURCE; } dev_err_ratelimited(disk_to_dev(nbd->disk), "Send control failed (result %d)\n", result); @@ -711,7 +715,7 @@ static int nbd_send_cmd(struct nbd_device *nbd, struct nbd_cmd *cmd, int index) nsock->pending = req; nsock->sent = sent; set_bit(NBD_CMD_REQUEUED, &cmd->flags); - return BLK_STS_RESOURCE; + return (__force int)BLK_STS_RESOURCE; } dev_err(disk_to_dev(nbd->disk), "Send data failed (result %d)\n", @@ -1008,7 +1012,7 @@ static int wait_for_reconnect(struct nbd_device *nbd) return !test_bit(NBD_RT_DISCONNECTED, &config->runtime_flags); }

-static int nbd_handle_cmd(struct nbd_cmd *cmd, int index) +static blk_status_t nbd_handle_cmd(struct nbd_cmd *cmd, int index) { struct request *req = blk_mq_rq_from_pdu(cmd); struct nbd_device *nbd = cmd->nbd; @@ -1022,14 +1026,14 @@ static int nbd_handle_cmd(struct nbd_cmd *cmd, int index) if (!config) { dev_err_ratelimited(disk_to_dev(nbd->disk), "Socks array is empty\n"); - return -EINVAL; + return BLK_STS_IOERR; }

if (index >= config->num_connections) { dev_err_ratelimited(disk_to_dev(nbd->disk), "Attempted send on invalid socket\n"); nbd_config_put(nbd); - return -EINVAL; + return BLK_STS_IOERR; } cmd->status = BLK_STS_OK; again: @@ -1052,7 +1056,7 @@ static int nbd_handle_cmd(struct nbd_cmd *cmd, int index) */ sock_shutdown(nbd); nbd_config_put(nbd); - return -EIO; + return BLK_STS_IOERR; } goto again; } @@ -1065,7 +1069,7 @@ static int nbd_handle_cmd(struct nbd_cmd *cmd, int index) blk_mq_start_request(req); if (unlikely(nsock->pending && nsock->pending != req)) { nbd_requeue_cmd(cmd); - ret = 0; + ret = BLK_STS_OK; goto out; } /* @@ -1084,19 +1088,19 @@ static int nbd_handle_cmd(struct nbd_cmd *cmd, int index) "Request send failed, requeueing\n"); nbd_mark_nsock_dead(nbd, nsock, 1); nbd_requeue_cmd(cmd); - ret = 0; + ret = BLK_STS_OK; } out: mutex_unlock(&nsock->tx_lock); nbd_config_put(nbd); - return ret; + return ret < 0 ? BLK_STS_IOERR : (__force blk_status_t)ret; }

static blk_status_t nbd_queue_rq(struct blk_mq_hw_ctx *hctx, const struct blk_mq_queue_data *bd) { struct nbd_cmd *cmd = blk_mq_rq_to_pdu(bd->rq); - int ret; + blk_status_t ret;

/* * Since we look at the bio's to send the request over the network we @@ -1116,10 +1120,6 @@ static blk_status_t nbd_queue_rq(struct blk_mq_hw_ctx *hctx, * appropriate. */ ret = nbd_handle_cmd(cmd, hctx->queue_num); - if (ret < 0) - ret = BLK_STS_IOERR; - else if (!ret) - ret = BLK_STS_OK; mutex_unlock(&cmd->lock);

return ret;