spi: spidev: remove debug messages that access spidev->spi without locking

stable inclusion
from stable-v5.10.166
commit 300da569a12808adb7acd0dc798f0437a8423fa7
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7TH9O

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=300da569a12808adb7acd0dc798f0437a8423fa7

--------------------------------

[ Upstream commit 6b35b173 ]

The two debug messages in spidev_open() dereference spidev->spi without
taking the lock and without checking if it's not null. This can lead to
a crash. Drop the messages as they're not needed - the user-space will
get informed about ENOMEM with the syscall return value.
Signed-off-by: NBartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20230106100719.196243-2-brgl@bgdev.plSigned-off-by: NMark Brown <broonie@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: Nsanglipeng <sanglipeng1@jd.com>

drivers/spi/spidev.c

@@ -592,7 +592,6 @@ static int spidev_open(struct inode *inode, struct file *filp)
 	if (!spidev->tx_buffer) {
 		spidev->tx_buffer = kmalloc(bufsiz, GFP_KERNEL);
 		if (!spidev->tx_buffer) {
-			dev_dbg(&spidev->spi->dev, "open/ENOMEM\n");
 			status = -ENOMEM;
 			goto err_find_dev;
 		}
@@ -601,7 +600,6 @@ static int spidev_open(struct inode *inode, struct file *filp)
 	if (!spidev->rx_buffer) {
 		spidev->rx_buffer = kmalloc(bufsiz, GFP_KERNEL);
 		if (!spidev->rx_buffer) {
-			dev_dbg(&spidev->spi->dev, "open/ENOMEM\n");
 			status = -ENOMEM;
 			goto err_alloc_rx_buf;
 		}