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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 /arch/arm/mm/dump.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 'arch/arm/mm/dump.c')
-rw-r--r--arch/arm/mm/dump.c479
1 files changed, 479 insertions, 0 deletions
diff --git a/arch/arm/mm/dump.c b/arch/arm/mm/dump.c
new file mode 100644
index 000000000..cd032522d
--- /dev/null
+++ b/arch/arm/mm/dump.c
@@ -0,0 +1,479 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Debug helper to dump the current kernel pagetables of the system
+ * so that we can see what the various memory ranges are set to.
+ *
+ * Derived from x86 implementation:
+ * (C) Copyright 2008 Intel Corporation
+ *
+ * Author: Arjan van de Ven <arjan@linux.intel.com>
+ */
+#include <linux/debugfs.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/seq_file.h>
+
+#include <asm/domain.h>
+#include <asm/fixmap.h>
+#include <asm/page.h>
+#include <asm/ptdump.h>
+
+static struct addr_marker address_markers[] = {
+#ifdef CONFIG_KASAN
+ { KASAN_SHADOW_START, "Kasan shadow start"},
+ { KASAN_SHADOW_END, "Kasan shadow end"},
+#endif
+ { MODULES_VADDR, "Modules" },
+ { PAGE_OFFSET, "Kernel Mapping" },
+ { 0, "vmalloc() Area" },
+ { FDT_FIXED_BASE, "FDT Area" },
+ { FIXADDR_START, "Fixmap Area" },
+ { VECTORS_BASE, "Vectors" },
+ { VECTORS_BASE + PAGE_SIZE * 2, "Vectors End" },
+ { -1, NULL },
+};
+
+#define pt_dump_seq_printf(m, fmt, args...) \
+({ \
+ if (m) \
+ seq_printf(m, fmt, ##args); \
+})
+
+#define pt_dump_seq_puts(m, fmt) \
+({ \
+ if (m) \
+ seq_printf(m, fmt); \
+})
+
+struct pg_state {
+ struct seq_file *seq;
+ const struct addr_marker *marker;
+ unsigned long start_address;
+ unsigned level;
+ u64 current_prot;
+ bool check_wx;
+ unsigned long wx_pages;
+ const char *current_domain;
+};
+
+struct prot_bits {
+ u64 mask;
+ u64 val;
+ const char *set;
+ const char *clear;
+ bool ro_bit;
+ bool nx_bit;
+};
+
+static const struct prot_bits pte_bits[] = {
+ {
+ .mask = L_PTE_USER,
+ .val = L_PTE_USER,
+ .set = "USR",
+ .clear = " ",
+ }, {
+ .mask = L_PTE_RDONLY,
+ .val = L_PTE_RDONLY,
+ .set = "ro",
+ .clear = "RW",
+ .ro_bit = true,
+ }, {
+ .mask = L_PTE_XN,
+ .val = L_PTE_XN,
+ .set = "NX",
+ .clear = "x ",
+ .nx_bit = true,
+ }, {
+ .mask = L_PTE_SHARED,
+ .val = L_PTE_SHARED,
+ .set = "SHD",
+ .clear = " ",
+ }, {
+ .mask = L_PTE_MT_MASK,
+ .val = L_PTE_MT_UNCACHED,
+ .set = "SO/UNCACHED",
+ }, {
+ .mask = L_PTE_MT_MASK,
+ .val = L_PTE_MT_BUFFERABLE,
+ .set = "MEM/BUFFERABLE/WC",
+ }, {
+ .mask = L_PTE_MT_MASK,
+ .val = L_PTE_MT_WRITETHROUGH,
+ .set = "MEM/CACHED/WT",
+ }, {
+ .mask = L_PTE_MT_MASK,
+ .val = L_PTE_MT_WRITEBACK,
+ .set = "MEM/CACHED/WBRA",
+#ifndef CONFIG_ARM_LPAE
+ }, {
+ .mask = L_PTE_MT_MASK,
+ .val = L_PTE_MT_MINICACHE,
+ .set = "MEM/MINICACHE",
+#endif
+ }, {
+ .mask = L_PTE_MT_MASK,
+ .val = L_PTE_MT_WRITEALLOC,
+ .set = "MEM/CACHED/WBWA",
+ }, {
+ .mask = L_PTE_MT_MASK,
+ .val = L_PTE_MT_DEV_SHARED,
+ .set = "DEV/SHARED",
+#ifndef CONFIG_ARM_LPAE
+ }, {
+ .mask = L_PTE_MT_MASK,
+ .val = L_PTE_MT_DEV_NONSHARED,
+ .set = "DEV/NONSHARED",
+#endif
+ }, {
+ .mask = L_PTE_MT_MASK,
+ .val = L_PTE_MT_DEV_WC,
+ .set = "DEV/WC",
+ }, {
+ .mask = L_PTE_MT_MASK,
+ .val = L_PTE_MT_DEV_CACHED,
+ .set = "DEV/CACHED",
+ },
+};
+
+static const struct prot_bits section_bits[] = {
+#ifdef CONFIG_ARM_LPAE
+ {
+ .mask = PMD_SECT_USER,
+ .val = PMD_SECT_USER,
+ .set = "USR",
+ }, {
+ .mask = L_PMD_SECT_RDONLY | PMD_SECT_AP2,
+ .val = L_PMD_SECT_RDONLY | PMD_SECT_AP2,
+ .set = "ro",
+ .clear = "RW",
+ .ro_bit = true,
+#elif __LINUX_ARM_ARCH__ >= 6
+ {
+ .mask = PMD_SECT_APX | PMD_SECT_AP_READ | PMD_SECT_AP_WRITE,
+ .val = PMD_SECT_APX | PMD_SECT_AP_WRITE,
+ .set = " ro",
+ .ro_bit = true,
+ }, {
+ .mask = PMD_SECT_APX | PMD_SECT_AP_READ | PMD_SECT_AP_WRITE,
+ .val = PMD_SECT_AP_WRITE,
+ .set = " RW",
+ }, {
+ .mask = PMD_SECT_APX | PMD_SECT_AP_READ | PMD_SECT_AP_WRITE,
+ .val = PMD_SECT_AP_READ,
+ .set = "USR ro",
+ }, {
+ .mask = PMD_SECT_APX | PMD_SECT_AP_READ | PMD_SECT_AP_WRITE,
+ .val = PMD_SECT_AP_READ | PMD_SECT_AP_WRITE,
+ .set = "USR RW",
+#else /* ARMv4/ARMv5 */
+ /* These are approximate */
+ {
+ .mask = PMD_SECT_AP_READ | PMD_SECT_AP_WRITE,
+ .val = 0,
+ .set = " ro",
+ .ro_bit = true,
+ }, {
+ .mask = PMD_SECT_AP_READ | PMD_SECT_AP_WRITE,
+ .val = PMD_SECT_AP_WRITE,
+ .set = " RW",
+ }, {
+ .mask = PMD_SECT_AP_READ | PMD_SECT_AP_WRITE,
+ .val = PMD_SECT_AP_READ,
+ .set = "USR ro",
+ }, {
+ .mask = PMD_SECT_AP_READ | PMD_SECT_AP_WRITE,
+ .val = PMD_SECT_AP_READ | PMD_SECT_AP_WRITE,
+ .set = "USR RW",
+#endif
+ }, {
+ .mask = PMD_SECT_XN,
+ .val = PMD_SECT_XN,
+ .set = "NX",
+ .clear = "x ",
+ .nx_bit = true,
+ }, {
+ .mask = PMD_SECT_S,
+ .val = PMD_SECT_S,
+ .set = "SHD",
+ .clear = " ",
+ },
+};
+
+struct pg_level {
+ const char *name;
+ const struct prot_bits *bits;
+ size_t num;
+ u64 mask;
+ const struct prot_bits *ro_bit;
+ const struct prot_bits *nx_bit;
+};
+
+static struct pg_level pg_level[] = {
+ {
+ }, { /* pgd */
+ }, { /* p4d */
+ }, { /* pud */
+ }, { /* pmd */
+ .name = (CONFIG_PGTABLE_LEVELS > 2) ? "PMD" : "PGD",
+ .bits = section_bits,
+ .num = ARRAY_SIZE(section_bits),
+ }, { /* pte */
+ .name = "PTE",
+ .bits = pte_bits,
+ .num = ARRAY_SIZE(pte_bits),
+ },
+};
+
+static void dump_prot(struct pg_state *st, const struct prot_bits *bits, size_t num)
+{
+ unsigned i;
+
+ for (i = 0; i < num; i++, bits++) {
+ const char *s;
+
+ if ((st->current_prot & bits->mask) == bits->val)
+ s = bits->set;
+ else
+ s = bits->clear;
+
+ if (s)
+ pt_dump_seq_printf(st->seq, " %s", s);
+ }
+}
+
+static void note_prot_wx(struct pg_state *st, unsigned long addr)
+{
+ if (!st->check_wx)
+ return;
+ if ((st->current_prot & pg_level[st->level].ro_bit->mask) ==
+ pg_level[st->level].ro_bit->val)
+ return;
+ if ((st->current_prot & pg_level[st->level].nx_bit->mask) ==
+ pg_level[st->level].nx_bit->val)
+ return;
+
+ WARN_ONCE(1, "arm/mm: Found insecure W+X mapping at address %pS\n",
+ (void *)st->start_address);
+
+ st->wx_pages += (addr - st->start_address) / PAGE_SIZE;
+}
+
+static void note_page(struct pg_state *st, unsigned long addr,
+ unsigned int level, u64 val, const char *domain)
+{
+ static const char units[] = "KMGTPE";
+ u64 prot = val & pg_level[level].mask;
+
+ if (!st->level) {
+ st->level = level;
+ st->current_prot = prot;
+ st->current_domain = domain;
+ pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name);
+ } else if (prot != st->current_prot || level != st->level ||
+ domain != st->current_domain ||
+ addr >= st->marker[1].start_address) {
+ const char *unit = units;
+ unsigned long delta;
+
+ if (st->current_prot) {
+ note_prot_wx(st, addr);
+ pt_dump_seq_printf(st->seq, "0x%08lx-0x%08lx ",
+ st->start_address, addr);
+
+ delta = (addr - st->start_address) >> 10;
+ while (!(delta & 1023) && unit[1]) {
+ delta >>= 10;
+ unit++;
+ }
+ pt_dump_seq_printf(st->seq, "%9lu%c %s", delta, *unit,
+ pg_level[st->level].name);
+ if (st->current_domain)
+ pt_dump_seq_printf(st->seq, " %s",
+ st->current_domain);
+ if (pg_level[st->level].bits)
+ dump_prot(st, pg_level[st->level].bits, pg_level[st->level].num);
+ pt_dump_seq_printf(st->seq, "\n");
+ }
+
+ if (addr >= st->marker[1].start_address) {
+ st->marker++;
+ pt_dump_seq_printf(st->seq, "---[ %s ]---\n",
+ st->marker->name);
+ }
+ st->start_address = addr;
+ st->current_prot = prot;
+ st->current_domain = domain;
+ st->level = level;
+ }
+}
+
+static void walk_pte(struct pg_state *st, pmd_t *pmd, unsigned long start,
+ const char *domain)
+{
+ pte_t *pte = pte_offset_kernel(pmd, 0);
+ unsigned long addr;
+ unsigned i;
+
+ for (i = 0; i < PTRS_PER_PTE; i++, pte++) {
+ addr = start + i * PAGE_SIZE;
+ note_page(st, addr, 5, pte_val(*pte), domain);
+ }
+}
+
+static const char *get_domain_name(pmd_t *pmd)
+{
+#ifndef CONFIG_ARM_LPAE
+ switch (pmd_val(*pmd) & PMD_DOMAIN_MASK) {
+ case PMD_DOMAIN(DOMAIN_KERNEL):
+ return "KERNEL ";
+ case PMD_DOMAIN(DOMAIN_USER):
+ return "USER ";
+ case PMD_DOMAIN(DOMAIN_IO):
+ return "IO ";
+ case PMD_DOMAIN(DOMAIN_VECTORS):
+ return "VECTORS";
+ default:
+ return "unknown";
+ }
+#endif
+ return NULL;
+}
+
+static void walk_pmd(struct pg_state *st, pud_t *pud, unsigned long start)
+{
+ pmd_t *pmd = pmd_offset(pud, 0);
+ unsigned long addr;
+ unsigned i;
+ const char *domain;
+
+ for (i = 0; i < PTRS_PER_PMD; i++, pmd++) {
+ addr = start + i * PMD_SIZE;
+ domain = get_domain_name(pmd);
+ if (pmd_none(*pmd) || pmd_leaf(*pmd) || !pmd_present(*pmd))
+ note_page(st, addr, 4, pmd_val(*pmd), domain);
+ else
+ walk_pte(st, pmd, addr, domain);
+
+ if (SECTION_SIZE < PMD_SIZE && pmd_leaf(pmd[1])) {
+ addr += SECTION_SIZE;
+ pmd++;
+ domain = get_domain_name(pmd);
+ note_page(st, addr, 4, pmd_val(*pmd), domain);
+ }
+ }
+}
+
+static void walk_pud(struct pg_state *st, p4d_t *p4d, unsigned long start)
+{
+ pud_t *pud = pud_offset(p4d, 0);
+ unsigned long addr;
+ unsigned i;
+
+ for (i = 0; i < PTRS_PER_PUD; i++, pud++) {
+ addr = start + i * PUD_SIZE;
+ if (!pud_none(*pud)) {
+ walk_pmd(st, pud, addr);
+ } else {
+ note_page(st, addr, 3, pud_val(*pud), NULL);
+ }
+ }
+}
+
+static void walk_p4d(struct pg_state *st, pgd_t *pgd, unsigned long start)
+{
+ p4d_t *p4d = p4d_offset(pgd, 0);
+ unsigned long addr;
+ unsigned i;
+
+ for (i = 0; i < PTRS_PER_P4D; i++, p4d++) {
+ addr = start + i * P4D_SIZE;
+ if (!p4d_none(*p4d)) {
+ walk_pud(st, p4d, addr);
+ } else {
+ note_page(st, addr, 2, p4d_val(*p4d), NULL);
+ }
+ }
+}
+
+static void walk_pgd(struct pg_state *st, struct mm_struct *mm,
+ unsigned long start)
+{
+ pgd_t *pgd = pgd_offset(mm, 0UL);
+ unsigned i;
+ unsigned long addr;
+
+ for (i = 0; i < PTRS_PER_PGD; i++, pgd++) {
+ addr = start + i * PGDIR_SIZE;
+ if (!pgd_none(*pgd)) {
+ walk_p4d(st, pgd, addr);
+ } else {
+ note_page(st, addr, 1, pgd_val(*pgd), NULL);
+ }
+ }
+}
+
+void ptdump_walk_pgd(struct seq_file *m, struct ptdump_info *info)
+{
+ struct pg_state st = {
+ .seq = m,
+ .marker = info->markers,
+ .check_wx = false,
+ };
+
+ walk_pgd(&st, info->mm, info->base_addr);
+ note_page(&st, 0, 0, 0, NULL);
+}
+
+static void __init ptdump_initialize(void)
+{
+ unsigned i, j;
+
+ for (i = 0; i < ARRAY_SIZE(pg_level); i++)
+ if (pg_level[i].bits)
+ for (j = 0; j < pg_level[i].num; j++) {
+ pg_level[i].mask |= pg_level[i].bits[j].mask;
+ if (pg_level[i].bits[j].ro_bit)
+ pg_level[i].ro_bit = &pg_level[i].bits[j];
+ if (pg_level[i].bits[j].nx_bit)
+ pg_level[i].nx_bit = &pg_level[i].bits[j];
+ }
+#ifdef CONFIG_KASAN
+ address_markers[4].start_address = VMALLOC_START;
+#else
+ address_markers[2].start_address = VMALLOC_START;
+#endif
+}
+
+static struct ptdump_info kernel_ptdump_info = {
+ .mm = &init_mm,
+ .markers = address_markers,
+ .base_addr = 0,
+};
+
+void ptdump_check_wx(void)
+{
+ struct pg_state st = {
+ .seq = NULL,
+ .marker = (struct addr_marker[]) {
+ { 0, NULL},
+ { -1, NULL},
+ },
+ .check_wx = true,
+ };
+
+ walk_pgd(&st, &init_mm, 0);
+ note_page(&st, 0, 0, 0, NULL);
+ if (st.wx_pages)
+ pr_warn("Checked W+X mappings: FAILED, %lu W+X pages found\n",
+ st.wx_pages);
+ else
+ pr_info("Checked W+X mappings: passed, no W+X pages found\n");
+}
+
+static int __init ptdump_init(void)
+{
+ ptdump_initialize();
+ ptdump_debugfs_register(&kernel_ptdump_info, "kernel_page_tables");
+ return 0;
+}
+__initcall(ptdump_init);