On 2023/9/28 9:13, Douglas Gilbert wrote:
On 2023-09-22 05:28, Wenchao Hao wrote:Create directory scsi_debug in the root of the debugfs filesystem. Prepare to add interface for manage error injection. Acked-by: Douglas Gilbert <dgilbert@xxxxxxxxxxxx> Signed-off-by: Wenchao Hao <haowenchao2@xxxxxxxxxx> --- drivers/scsi/scsi_debug.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 9c0af50501f9..35c336271b13 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -41,6 +41,7 @@ #include <linux/random.h> #include <linux/xarray.h> #include <linux/prefetch.h> +#include <linux/debugfs.h> #include <net/checksum.h> @@ -862,6 +863,8 @@ static const int device_qfull_result = static const int condition_met_result = SAM_STAT_CONDITION_MET; +static struct dentry *sdebug_debugfs_root; + /* Only do the extra work involved in logical block provisioning if one or * more of the lbpu, lbpws or lbpws10 parameters are given and we are doing @@ -7011,6 +7014,8 @@ static int __init scsi_debug_init(void) goto driver_unreg; } + sdebug_debugfs_root = debugfs_create_dir("scsi_debug", NULL);debugfs_create_dir() can fail and return NULL. Looking at other drivers, most seem to assume it will work. Since the scsi_debug driver is often used to test abnormal situations, perhaps adding something like: if (!sdebug_debugfs_root) pr_info("%s: failed to create initial debugfs directory\n", __func__); might save someone a bit of time if a NULL dereference on sdebug_debugfs_root follows later. That is what the mpt3sas driver does.
Yes, I would fix it by checking return value of debugfs related call after your review suggestions for other patches.
Doug Gilbert+ for (k = 0; k < hosts_to_add; k++) { if (want_store && k == 0) { ret = sdebug_add_host_helper(idx); @@ -7057,6 +7062,7 @@ static void __exit scsi_debug_exit(void) sdebug_erase_all_stores(false); xa_destroy(per_store_ap); + debugfs_remove(sdebug_debugfs_root); } device_initcall(scsi_debug_init);
