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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /lib/sys_info.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'lib/sys_info.c')
-rw-r--r--lib/sys_info.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/lib/sys_info.c b/lib/sys_info.c
new file mode 100644
index 000000000..f32a06ec9
--- /dev/null
+++ b/lib/sys_info.c
@@ -0,0 +1,166 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/array_size.h>
+#include <linux/bitops.h>
+#include <linux/cleanup.h>
+#include <linux/console.h>
+#include <linux/log2.h>
+#include <linux/kernel.h>
+#include <linux/ftrace.h>
+#include <linux/nmi.h>
+#include <linux/sched/debug.h>
+#include <linux/string.h>
+#include <linux/sysctl.h>
+
+#include <linux/sys_info.h>
+
+static const char * const si_names[] = {
+ [ilog2(SYS_INFO_TASKS)] = "tasks",
+ [ilog2(SYS_INFO_MEM)] = "mem",
+ [ilog2(SYS_INFO_TIMERS)] = "timers",
+ [ilog2(SYS_INFO_LOCKS)] = "locks",
+ [ilog2(SYS_INFO_FTRACE)] = "ftrace",
+ [ilog2(SYS_INFO_PANIC_CONSOLE_REPLAY)] = "",
+ [ilog2(SYS_INFO_ALL_BT)] = "all_bt",
+ [ilog2(SYS_INFO_BLOCKED_TASKS)] = "blocked_tasks",
+};
+
+/*
+ * Default kernel sys_info mask.
+ * If a kernel module calls sys_info() with "parameter == 0", then
+ * this mask will be used.
+ */
+static unsigned long kernel_si_mask;
+
+/* Expecting string like "xxx_sys_info=tasks,mem,timers,locks,ftrace,..." */
+unsigned long sys_info_parse_param(char *str)
+{
+ unsigned long si_bits = 0;
+ char *s, *name;
+ int i;
+
+ s = str;
+ while ((name = strsep(&s, ",")) && *name) {
+ i = match_string(si_names, ARRAY_SIZE(si_names), name);
+ if (i >= 0)
+ __set_bit(i, &si_bits);
+ }
+
+ return si_bits;
+}
+
+#ifdef CONFIG_SYSCTL
+
+static int sys_info_write_handler(const struct ctl_table *table,
+ void *buffer, size_t *lenp, loff_t *ppos,
+ unsigned long *si_bits_global)
+{
+ unsigned long si_bits;
+ int ret;
+
+ ret = proc_dostring(table, 1, buffer, lenp, ppos);
+ if (ret)
+ return ret;
+
+ si_bits = sys_info_parse_param(table->data);
+
+ /* The access to the global value is not synchronized. */
+ WRITE_ONCE(*si_bits_global, si_bits);
+
+ return 0;
+}
+
+static int sys_info_read_handler(const struct ctl_table *table,
+ void *buffer, size_t *lenp, loff_t *ppos,
+ unsigned long *si_bits_global)
+{
+ unsigned long si_bits;
+ unsigned int len = 0;
+ char *delim = "";
+ unsigned int i;
+
+ /* The access to the global value is not synchronized. */
+ si_bits = READ_ONCE(*si_bits_global);
+
+ for_each_set_bit(i, &si_bits, ARRAY_SIZE(si_names)) {
+ if (*si_names[i]) {
+ len += scnprintf(table->data + len, table->maxlen - len,
+ "%s%s", delim, si_names[i]);
+ delim = ",";
+ }
+ }
+
+ return proc_dostring(table, 0, buffer, lenp, ppos);
+}
+
+int sysctl_sys_info_handler(const struct ctl_table *ro_table, int write,
+ void *buffer, size_t *lenp,
+ loff_t *ppos)
+{
+ struct ctl_table table;
+ unsigned int i;
+ size_t maxlen;
+
+ maxlen = 0;
+ for (i = 0; i < ARRAY_SIZE(si_names); i++)
+ maxlen += strlen(si_names[i]) + 1;
+
+ char *names __free(kfree) = kzalloc(maxlen, GFP_KERNEL);
+ if (!names)
+ return -ENOMEM;
+
+ table = *ro_table;
+ table.data = names;
+ table.maxlen = maxlen;
+
+ if (write)
+ return sys_info_write_handler(&table, buffer, lenp, ppos, ro_table->data);
+ else
+ return sys_info_read_handler(&table, buffer, lenp, ppos, ro_table->data);
+}
+
+static const struct ctl_table sys_info_sysctls[] = {
+ {
+ .procname = "kernel_sys_info",
+ .data = &kernel_si_mask,
+ .maxlen = sizeof(kernel_si_mask),
+ .mode = 0644,
+ .proc_handler = sysctl_sys_info_handler,
+ },
+};
+
+static int __init sys_info_sysctl_init(void)
+{
+ register_sysctl_init("kernel", sys_info_sysctls);
+ return 0;
+}
+subsys_initcall(sys_info_sysctl_init);
+#endif
+
+static void __sys_info(unsigned long si_mask)
+{
+ if (si_mask & SYS_INFO_TASKS)
+ show_state();
+
+ if (si_mask & SYS_INFO_MEM)
+ show_mem();
+
+ if (si_mask & SYS_INFO_TIMERS)
+ sysrq_timer_list_show();
+
+ if (si_mask & SYS_INFO_LOCKS)
+ debug_show_all_locks();
+
+ if (si_mask & SYS_INFO_FTRACE)
+ ftrace_dump(DUMP_ALL);
+
+ if (si_mask & SYS_INFO_ALL_BT)
+ trigger_all_cpu_backtrace();
+
+ if (si_mask & SYS_INFO_BLOCKED_TASKS)
+ show_state_filter(TASK_UNINTERRUPTIBLE);
+}
+
+void sys_info(unsigned long si_mask)
+{
+ __sys_info(si_mask ? : kernel_si_mask);
+}