[PATCH v3 5/8] arm64: dump: Make kernel page table dumper dynamic again

Steve Capper steve.capper at arm.com
Thu May 10 09:23:44 PDT 2018


The kernel page table dumper assumes that the placement of VA regions is
constant and determined at compile time. As we are about to introduce
variable VA logic, we need to be able to determine certain regions at
boot time.

This patch adds logic to the kernel page table dumper s.t. these regions
can be computed at boot time.

Signed-off-by: Steve Capper <steve.capper at arm.com>
---
 arch/arm64/mm/dump.c | 58 ++++++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 47 insertions(+), 11 deletions(-)

diff --git a/arch/arm64/mm/dump.c b/arch/arm64/mm/dump.c
index 76e8857b2baf..c1030b3ca3c7 100644
--- a/arch/arm64/mm/dump.c
+++ b/arch/arm64/mm/dump.c
@@ -29,23 +29,45 @@
 #include <asm/pgtable-hwdef.h>
 #include <asm/ptdump.h>
 
-static const struct addr_marker address_markers[] = {
-	{ PAGE_OFFSET,			"Linear Mapping start" },
-	{ VA_START,			"Linear Mapping end" },
+
+enum address_markers_idx {
+	PAGE_OFFSET_NR = 0,
+	VA_START_NR,
+#ifdef CONFIG_KASAN
+	KASAN_START_NR,
+	KASAN_END_NR,
+#endif
+	MODULES_START_NR,
+	MODULES_END_NR,
+	VMALLOC_START_NR,
+	VMALLOC_END_NR,
+	FIXADDR_START_NR,
+	FIXADDR_END_NR,
+	PCI_START_NR,
+	PCI_END_NR,
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+	VMEMMAP_START_NR,
+#endif
+	END_NR
+};
+
+static struct addr_marker address_markers[] = {
+	{ 0 /* PAGE_OFFSET */,		"Linear Mapping start" },
+	{ 0 /* VA_START */,		"Linear Mapping end" },
 #ifdef CONFIG_KASAN
-	{ KASAN_SHADOW_START,		"Kasan shadow start" },
+	{ 0 /* KASAN_SHADOW_START */,	"Kasan shadow start" },
 	{ KASAN_SHADOW_END,		"Kasan shadow end" },
 #endif
 	{ MODULES_VADDR,		"Modules start" },
 	{ MODULES_END,			"Modules end" },
 	{ VMALLOC_START,		"vmalloc() Area" },
-	{ VMALLOC_END,			"vmalloc() End" },
-	{ FIXADDR_START,		"Fixmap start" },
-	{ FIXADDR_TOP,			"Fixmap end" },
-	{ PCI_IO_START,			"PCI I/O start" },
-	{ PCI_IO_END,			"PCI I/O end" },
+	{ 0 /* VMALLOC_END */,		"vmalloc() End" },
+	{ 0 /* FIXADDR_START */,	"Fixmap start" },
+	{ 0 /* FIXADDR_TOP */,		"Fixmap end" },
+	{ 0 /* PCI_IO_START */,		"PCI I/O start" },
+	{ 0 /* PCI_IO_END */,		"PCI I/O end" },
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
-	{ VMEMMAP_START,		"vmemmap" },
+	{ 0 /* VMEMMAP_START */,	"vmemmap" },
 #endif
 	{ -1,				NULL },
 };
@@ -381,7 +403,6 @@ static void ptdump_initialize(void)
 static struct ptdump_info kernel_ptdump_info = {
 	.mm		= &init_mm,
 	.markers	= address_markers,
-	.base_addr	= PAGE_OFFSET,
 };
 
 void ptdump_check_wx(void)
@@ -407,6 +428,21 @@ void ptdump_check_wx(void)
 static int ptdump_init(void)
 {
 	ptdump_initialize();
+	kernel_ptdump_info.base_addr = PAGE_OFFSET;
+	address_markers[PAGE_OFFSET_NR].start_address = PAGE_OFFSET;
+	address_markers[VA_START_NR].start_address = VA_START;
+#ifdef CONFIG_KASAN
+	address_markers[KASAN_START_NR].start_address = KASAN_SHADOW_START;
+#endif
+	address_markers[VMALLOC_END_NR].start_address = VMALLOC_END;
+	address_markers[FIXADDR_START_NR].start_address = FIXADDR_START;
+	address_markers[FIXADDR_END_NR].start_address = FIXADDR_TOP;
+	address_markers[PCI_START_NR].start_address = PCI_IO_START;
+	address_markers[PCI_END_NR].start_address = PCI_IO_END;
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+	address_markers[VMEMMAP_START_NR].start_address = VMEMMAP_START;
+#endif
+
 	return ptdump_debugfs_register(&kernel_ptdump_info,
 					"kernel_page_tables");
 }
-- 
2.11.0




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