This new parameter storage_quiet_discovery defaults to 0 and behavior is
unchanged. If its set to 1 on the kernel line then sd_printk and
sdev_printk are disabled for printing. The default logging can
be re-enabled any time after boot using /etc/sysctl.conf by
setting dev.scsi.storage_quiet_discovery = 0.
systctl -w dev.scsi.storage_quiet_discovery=0 will also change it
immediately back to logging.
Users can leave it set to 1 on the kernel line and 0 in the conf
file so it changes back to default after rc.sysinit.
This solves the tough problem of systems with 1000's of storage LUNS
consuming a system and preventing it from booting due to NMI's and
timeouts.
Signed-off-by: Laurence Oberman <loberman@xxxxxxxxxx>
---
Documentation/scsi/scsi-parameters.rst | 16 ++++++++++++++++
drivers/scsi/scsi.c | 6 ++++++
drivers/scsi/scsi_sysctl.c | 5 +++++
drivers/scsi/sd.h | 11 ++++++++---
include/scsi/scsi_device.h | 8 ++++++--
5 files changed, 41 insertions(+), 5 deletions(-)
diff --git a/Documentation/scsi/scsi-parameters.rst b/Documentation/scsi/scsi-parameters.rst
index c42c55e1e25e..3c6284ef7fd5 100644
--- a/Documentation/scsi/scsi-parameters.rst
+++ b/Documentation/scsi/scsi-parameters.rst
@@ -93,6 +93,22 @@ parameters may be changed at runtime by the command
S390-tools package, available for download at
https://github.com/ibm-s390-linux/s390-tools/blob/master/scripts/scsi_logging_level
+ scsi_mod.storage_quiet_discovery=
+ [SCSI] a parameter to control the printing from
+ sdev_printk and sd_printk for systems with large
+ amounts of LUNS.
+ Defaults to 0 so unchanged behavior.
+ If scsi_mod.storage_quiet_discovery=1 is added boot line
+ then the messages are not printed and can be enabled
+ after boot via
+ echo 0 >
+ /sys/module/scsi_mod/parameters/storage_quiet_discovery
+ Another option is using
+ sysctl -w dev.scsi.storage_quiet_discovery=0.
+ Leaving this set to 0 in /etc/sysctl.conf and setting
+ it to 1 on the kernel line will help for these large
+ LUN count configurations and ensure its back on after boot.
+
scsi_mod.scan= [SCSI] sync (default) scans SCSI busses as they are
discovered. async scans them in kernel threads,
allowing boot to proceed. none ignores them, expecting
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index 24619c3bebd5..b6b1b9ecc30e 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -86,6 +86,9 @@ unsigned int scsi_logging_level;
EXPORT_SYMBOL(scsi_logging_level);
#endif
+int storage_quiet_discovery = 0;
+EXPORT_SYMBOL(storage_quiet_discovery);
+
/*
* Domain for asynchronous system resume operations. It is marked 'exclusive'
* to avoid being included in the async_synchronize_full() that is invoked by
@@ -749,6 +752,9 @@ MODULE_LICENSE("GPL");
module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR);
MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels");
+module_param(storage_quiet_discovery, int, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(storage_quiet_discovery, "If set to 1 will silence SCSI and \
+ ALUA discovery logging on boot");
static int __init init_scsi(void)
{
diff --git a/drivers/scsi/scsi_sysctl.c b/drivers/scsi/scsi_sysctl.c
index 7259704a7f52..db9e4520ad4e 100644
--- a/drivers/scsi/scsi_sysctl.c
+++ b/drivers/scsi/scsi_sysctl.c
@@ -18,6 +18,11 @@ static struct ctl_table scsi_table[] = {
.maxlen = sizeof(scsi_logging_level),
.mode = 0644,
.proc_handler = proc_dointvec },
+ { .procname = "storage_quiet_discovery",
+ .data = &storage_quiet_discovery,
+ .maxlen = sizeof(storage_quiet_discovery),
+ .mode = 0644,
+ .proc_handler = proc_dointvec },
{ }
};
diff --git a/drivers/scsi/sd.h b/drivers/scsi/sd.h
index b59136c4125b..ede4d53a232a 100644
--- a/drivers/scsi/sd.h
+++ b/drivers/scsi/sd.h
@@ -133,11 +133,16 @@ static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
return container_of(disk->private_data, struct scsi_disk, driver);
}
+extern int storage_quiet_discovery;
+
#define sd_printk(prefix, sdsk, fmt, a...) \
- (sdsk)->disk ? \
- sdev_prefix_printk(prefix, (sdsk)->device, \
+ do { \
+ if (!storage_quiet_discovery) \
+ (sdsk)->disk ? \
+ sdev_prefix_printk(prefix, (sdsk)->device, \
(sdsk)->disk->disk_name, fmt, ##a) : \
- sdev_printk(prefix, (sdsk)->device, fmt, ##a)
+ sdev_printk(prefix, (sdsk)->device, fmt, ##a); \
+ } while (0)
#define sd_first_printk(prefix, sdsk, fmt, a...) \
do { \
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 1a5c9a3df6d6..ca71aa784d1e 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -258,8 +258,12 @@ __printf(4, 5) void
sdev_prefix_printk(const char *, const struct scsi_device *, const char *,
const char *, ...);
-#define sdev_printk(l, sdev, fmt, a...) \
- sdev_prefix_printk(l, sdev, NULL, fmt, ##a)
+extern int storage_quiet_discovery;
+
+#define sdev_printk(l, sdev, fmt, a...) ({ \
+ if (!storage_quiet_discovery) \
+ sdev_prefix_printk(l, sdev, NULL, fmt, ##a); \
+ })
__printf(3, 4) void
scmd_printk(const char *, const struct scsi_cmnd *, const char *, ...);
--
2.27.0
