Merge tag 'sysctl-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux

Pull sysctl updates from Luis Chamberlain:
"To help make the move of sysctls out of kernel/sysctl.c not incur a
size penalty sysctl has been changed to allow us to not require the
sentinel, the final empty element on the sysctl array. Joel Granados
has been doing all this work. On the v6.6 kernel we got the major
infrastructure changes required to support this. For v6.7-rc1 we have
all arch/ and drivers/ modified to remove the sentinel. Both arch and
driver changes have been on linux-next for a bit less than a month. It
is worth re-iterating the value:

- this helps reduce the overall build time size of the kernel and run
time memory consumed by the kernel by about ~64 bytes per array

- the extra 64-byte penalty is no longer inncurred now when we move
sysctls out from kernel/sysctl.c to their own files

For v6.8-rc1 expect removal of all the sentinels and also then the
unneeded check for procname == NULL.

The last two patches are fixes recently merged by Krister Johansen
which allow us again to use softlockup_panic early on boot. This used
to work but the alias work broke it. This is useful for folks who want
to detect softlockups super early rather than wait and spend money on
cloud solutions with nothing but an eventual hung kernel. Although
this hadn't gone through linux-next it's also a stable fix, so we
might as well roll through the fixes now"

* tag 'sysctl-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (23 commits)
watchdog: move softlockup_panic back to early_param
proc: sysctl: prevent aliased sysctls from getting passed to init
intel drm: Remove now superfluous sentinel element from ctl_table array
Drivers: hv: Remove now superfluous sentinel element from ctl_table array
raid: Remove now superfluous sentinel element from ctl_table array
fw loader: Remove the now superfluous sentinel element from ctl_table array
sgi-xp: Remove the now superfluous sentinel element from ctl_table array
vrf: Remove the now superfluous sentinel element from ctl_table array
char-misc: Remove the now superfluous sentinel element from ctl_table array
infiniband: Remove the now superfluous sentinel element from ctl_table array
macintosh: Remove the now superfluous sentinel element from ctl_table array
parport: Remove the now superfluous sentinel element from ctl_table array
scsi: Remove now superfluous sentinel element from ctl_table array
tty: Remove now superfluous sentinel element from ctl_table array
xen: Remove now superfluous sentinel element from ctl_table array
hpet: Remove now superfluous sentinel element from ctl_table array
c-sky: Remove now superfluous sentinel element from ctl_talbe array
powerpc: Remove now superfluous sentinel element from ctl_table arrays
riscv: Remove now superfluous sentinel element from ctl_table array
x86/vdso: Remove now superfluous sentinel element from ctl_table array
...

arch/arm/kernel/isa.c

···
 
 static unsigned int isa_membase, isa_portbase, isa_portshift;
 
-static struct ctl_table ctl_isa_vars[4] = {
+static struct ctl_table ctl_isa_vars[] = {
 	{
 		.procname	= "membase",
 		.data		= &isa_membase, 
···
 		.maxlen		= sizeof(isa_portshift),
 		.mode		= 0444,
 		.proc_handler	= proc_dointvec,
-	}, {}
+	},
 };
 
 static struct ctl_table_header *isa_sysctl_header;

arch/arm64/kernel/armv8_deprecated.c

···
 	int min;
 	int max;
 
-	/*
-	 * sysctl for this emulation + a sentinal entry.
-	 */
-	struct ctl_table sysctl[2];
+	/* sysctl for this emulation */
+	struct ctl_table sysctl;
 };
 
 #define ARM_OPCODE_CONDTEST_FAIL   0
···
 	update_insn_emulation_mode(insn, INSN_UNDEF);
 
 	if (insn->status != INSN_UNAVAILABLE) {
-		sysctl = &insn->sysctl[0];
+		sysctl = &insn->sysctl;
 
 		sysctl->mode = 0644;
 		sysctl->maxlen = sizeof(int);

arch/arm64/kernel/fpsimd.c

···
 		.proc_handler	= vec_proc_do_default_vl,
 		.extra1		= &vl_info[ARM64_VEC_SVE],
 	},
-	{ }
 };
 
 static int __init sve_sysctl_init(void)
···
 		.proc_handler	= vec_proc_do_default_vl,
 		.extra1		= &vl_info[ARM64_VEC_SME],
 	},
-	{ }
 };
 
 static int __init sme_sysctl_init(void)

arch/arm64/kernel/process.c

···
 		.extra1		= SYSCTL_ZERO,
 		.extra2		= SYSCTL_ONE,
 	},
-	{ }
 };
 
 static int __init tagged_addr_init(void)

arch/csky/abiv1/alignment.c

···
 		.mode = 0666,
 		.proc_handler = &proc_dointvec
 	},
-	{}
 };
 
 static int __init csky_alignment_init(void)

arch/powerpc/kernel/idle.c

···
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec,
 	},
-	{}
 };
 
 static int __init

arch/powerpc/platforms/pseries/mobility.c

···
 		.mode		= 0644,
 		.proc_handler	= proc_douintvec_minmax,
 	},
-	{}
 };
 
 static int __init register_nmi_wd_lpm_factor_sysctl(void)

arch/riscv/kernel/vector.c

···
 		.mode		= 0644,
 		.proc_handler	= proc_dobool,
 	},
-	{ }
 };
 
 static int __init riscv_v_sysctl_init(void)

arch/s390/appldata/appldata_base.c

···
 		.mode		= S_IRUGO | S_IWUSR,
 		.proc_handler	= appldata_interval_handler,
 	},
-	{ },
 };
 
 /*
···
 	if (ops->size > APPLDATA_MAX_REC_SIZE)
 		return -EINVAL;
 
-	/* The last entry must be an empty one */
-	ops->ctl_table = kcalloc(2, sizeof(struct ctl_table), GFP_KERNEL);
+	ops->ctl_table = kcalloc(1, sizeof(struct ctl_table), GFP_KERNEL);
 	if (!ops->ctl_table)
 		return -ENOMEM;
 

arch/s390/kernel/debug.c

···
 		.mode		= S_IRUGO | S_IWUSR,
 		.proc_handler	= s390dbf_procactive,
 	},
-	{ }
 };
 
 static struct ctl_table_header *s390dbf_sysctl_header;

arch/s390/kernel/topology.c

···
 		.mode		= 0644,
 		.proc_handler	= topology_ctl_handler,
 	},
-	{ },
 };
 
 static int __init topology_init(void)

arch/s390/mm/cmm.c

···
 		.mode		= 0644,
 		.proc_handler	= cmm_timeout_handler,
 	},
-	{ }
 };
 
 #ifdef CONFIG_CMM_IUCV

arch/s390/mm/pgalloc.c

···
 		.extra1		= SYSCTL_ZERO,
 		.extra2		= SYSCTL_ONE,
 	},
-	{ }
 };
 
 static int __init page_table_register_sysctl(void)

arch/x86/entry/vdso/vdso32-setup.c

···
 		.extra1		= SYSCTL_ZERO,
 		.extra2		= SYSCTL_ONE,
 	},
-	{}
 };
 
 static __init int ia32_binfmt_init(void)

arch/x86/kernel/cpu/intel.c

···
 		.extra1         = SYSCTL_ZERO,
 		.extra2         = SYSCTL_ONE,
 	},
-	{}
 };
 
 static int __init sld_mitigate_sysctl_init(void)

arch/x86/kernel/itmt.c

···
 		.extra1		= SYSCTL_ZERO,
 		.extra2		= SYSCTL_ONE,
 	},
-	{}
 };
 
 static struct ctl_table_header *itmt_sysctl_header;

drivers/base/firmware_loader/fallback_table.c

···
 		.extra1		= SYSCTL_ZERO,
 		.extra2		= SYSCTL_ONE,
 	},
-	{ }
 };
 
 static struct ctl_table_header *firmware_config_sysct_table_header;

drivers/char/hpet.c

···
 	 .mode = 0644,
 	 .proc_handler = proc_dointvec,
 	 },
-	{}
 };
 
 static struct ctl_table_header *sysctl_header;

drivers/char/ipmi/ipmi_poweroff.c

···
 	  .maxlen	= sizeof(poweroff_powercycle),
 	  .mode		= 0644,
 	  .proc_handler	= proc_dointvec },
-	{ }
 };
 
 static struct ctl_table_header *ipmi_table_header;

drivers/char/random.c

···
 		.mode		= 0444,
 		.proc_handler	= proc_do_uuid,
 	},
-	{ }
 };
 
 /*

drivers/gpu/drm/i915/i915_perf.c

···
 	 .extra1 = SYSCTL_ZERO,
 	 .extra2 = &oa_sample_rate_hard_limit,
 	 },
-	{}
 };
 
 static u32 num_perf_groups_per_gt(struct intel_gt *gt)

drivers/hv/hv_common.c

···
 		.extra1		= SYSCTL_ZERO,
 		.extra2		= SYSCTL_ONE
 	},
-	{}
 };
 
 static int hv_die_panic_notify_crash(struct notifier_block *self,

drivers/infiniband/core/iwcm.c

···
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec,
 	},
-	{ }
 };
 
 /*

drivers/infiniband/core/ucma.c

···
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec,
 	},
-	{ }
 };
 
 struct ucma_file {

drivers/macintosh/mac_hid.c

···
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec,
 	},
-	{ }
 };
 
 static struct ctl_table_header *mac_hid_sysctl_header;

drivers/md/md.c

···
 		.mode		= S_IRUGO|S_IWUSR,
 		.proc_handler	= proc_dointvec,
 	},
-	{ }
 };
 
 static int start_readonly;

drivers/misc/sgi-xp/xpc_main.c

···
 	 .proc_handler = proc_dointvec_minmax,
 	 .extra1 = &xpc_hb_check_min_interval,
 	 .extra2 = &xpc_hb_check_max_interval},
-	{}
 };
 static struct ctl_table xpc_sys_xpc[] = {
 	{
···
 	 .proc_handler = proc_dointvec_minmax,
 	 .extra1 = &xpc_disengage_min_timelimit,
 	 .extra2 = &xpc_disengage_max_timelimit},
-	{}
 };
 
 static struct ctl_table_header *xpc_sysctl;

drivers/net/vrf.c

···
 		/* set by the vrf_netns_init */
 		.extra1		= NULL,
 	},
-	{ },
 };
 
 static int vrf_netns_init_sysctl(struct net *net, struct netns_vrf *nn_vrf)

drivers/parport/procfs.c

···
 struct parport_sysctl_table {
 	struct ctl_table_header *port_header;
 	struct ctl_table_header *devices_header;
-	struct ctl_table vars[12];
-	struct ctl_table device_dir[2];
+#ifdef CONFIG_PARPORT_1284
+	struct ctl_table vars[10];
+#else
+	struct ctl_table vars[5];
+#endif /* IEEE 1284 support */
+	struct ctl_table device_dir[1];
 };
 
 static const struct parport_sysctl_table parport_sysctl_template = {
···
 			.proc_handler	= do_autoprobe
 		},
 #endif /* IEEE 1284 support */
-		{}
 	},
 	{
 		{
···
 			.mode		= 0444,
 			.proc_handler	= do_active_device
 		},
-		{}
 	},
 };
 
 struct parport_device_sysctl_table
 {
 	struct ctl_table_header *sysctl_header;
-	struct ctl_table vars[2];
-	struct ctl_table device_dir[2];
-	struct ctl_table devices_root_dir[2];
-	struct ctl_table port_dir[2];
-	struct ctl_table parport_dir[2];
-	struct ctl_table dev_dir[2];
+	struct ctl_table vars[1];
+	struct ctl_table device_dir[1];
 };
 
 static const struct parport_device_sysctl_table
···
 			.extra1		= (void*) &parport_min_timeslice_value,
 			.extra2		= (void*) &parport_max_timeslice_value
 		},
-		{}
 	},
 	{
 		{
···
 			.maxlen		= 0,
 			.mode		= 0555,
 		},
-		{}
 	}
 };
 
 struct parport_default_sysctl_table
 {
 	struct ctl_table_header *sysctl_header;
-	struct ctl_table vars[3];
-	struct ctl_table default_dir[2];
-	struct ctl_table parport_dir[2];
-	struct ctl_table dev_dir[2];
+	struct ctl_table vars[2];
 };
 
 static struct parport_default_sysctl_table
···
 			.extra1		= (void*) &parport_min_spintime_value,
 			.extra2		= (void*) &parport_max_spintime_value
 		},
-		{}
 	}
 };
 
···
 	t->vars[0].data = &port->spintime;
 	for (i = 0; i < 5; i++) {
 		t->vars[i].extra1 = port;
+#ifdef CONFIG_PARPORT_1284
 		t->vars[5 + i].extra2 = &port->probe_info[i];
+#endif /* IEEE 1284 support */
 	}
 
 	port_name_len = strnlen(port->name, PARPORT_NAME_MAX_LEN);

drivers/perf/arm_pmuv3.c

···
 		.extra1		= SYSCTL_ZERO,
 		.extra2		= SYSCTL_ONE,
 	},
-	{ }
 };
 
 static void armv8_pmu_register_sysctl_table(void)

drivers/scsi/scsi_sysctl.c

···
 	  .maxlen	= sizeof(scsi_logging_level),
 	  .mode		= 0644,
 	  .proc_handler	= proc_dointvec },
-	{ }
 };
 
 static struct ctl_table_header *scsi_table_header;

drivers/scsi/sg.c

···
 		.mode		= 0444,
 		.proc_handler	= proc_dointvec,
 	},
-	{}
 };
 
 static struct ctl_table_header *hdr;

drivers/tty/tty_io.c

···
 		.extra1		= SYSCTL_ZERO,
 		.extra2		= SYSCTL_ONE,
 	},
-	{ }
 };
 
 /*

drivers/xen/balloon.c

···
 		.extra1         = SYSCTL_ZERO,
 		.extra2         = SYSCTL_ONE,
 	},
-	{ }
 };
 
 #else

fs/proc/proc_sysctl.c

···
 	{"hung_task_panic",			"kernel.hung_task_panic" },
 	{"numa_zonelist_order",			"vm.numa_zonelist_order" },
 	{"softlockup_all_cpu_backtrace",	"kernel.softlockup_all_cpu_backtrace" },
-	{"softlockup_panic",			"kernel.softlockup_panic" },
 	{ }
 };
 
···
 	}
 
 	return NULL;
+}
+
+bool sysctl_is_alias(char *param)
+{
+	const char *alias = sysctl_find_alias(param);
+
+	return alias != NULL;
 }
 
 /* Set sysctl value passed on kernel command line. */

include/linux/sysctl.h

···
 extern struct ctl_table_header *register_sysctl_mount_point(const char *path);
 
 void do_sysctl_args(void);
+bool sysctl_is_alias(char *param);
 int do_proc_douintvec(struct ctl_table *table, int write,
 		      void *buffer, size_t *lenp, loff_t *ppos,
 		      int (*conv)(unsigned long *lvalp,
···
 
 static inline void do_sysctl_args(void)
 {
+}
+
+static inline bool sysctl_is_alias(char *param)
+{
+	return false;
 }
 #endif /* CONFIG_SYSCTL */
 

init/main.c

···
 {
 	size_t len = strlen(param);
 
+	/* Handle params aliased to sysctls */
+	if (sysctl_is_alias(param))
+		return 0;
+
 	repair_env_string(param, val);
 
 	/* Handle obsolete-style parameters */

kernel/watchdog.c

···
 static DEFINE_PER_CPU(bool, softlockup_touch_sync);
 static unsigned long soft_lockup_nmi_warn;
 
+static int __init softlockup_panic_setup(char *str)
+{
+	softlockup_panic = simple_strtoul(str, NULL, 0);
+	return 1;
+}
+__setup("softlockup_panic=", softlockup_panic_setup);
+
 static int __init nowatchdog_setup(char *str)
 {
 	watchdog_user_enabled = 0;