[PATCH] arm64: mm: Enhance Virtual kernel memory layout

[Kefeng Wang]

1) Show kernel excetion vector region and bss segment information.
2) Only show modules and PCI I/O with corresponding config enabled.
3) Each line with single pr_cont, or lead to anomalous print in dmesg.

Signed-off-by: Kefeng Wang <wangkefeng.wang at huawei.com>
---
With this patch,

[    0.000000] Virtual kernel memory layout:
[    0.000000]      vector : 0xffffff8008084800 - 0xffffff8008084f80   (     1 KB)
[    0.000000]     modules : 0xffffff8000000000 - 0xffffff8008000000   (   128 MB)
[    0.000000]     vmalloc : 0xffffff8008000000 - 0xffffffbdbfff0000   (   246 GB)
[    0.000000]       .text : 0xffffff8008080000 - 0xffffff8008753000   (  6988 KB)
[    0.000000]     .rodata : 0xffffff8008753000 - 0xffffff8008a3a000   (  2972 KB)
[    0.000000]       .init : 0xffffff8008a3a000 - 0xffffff8008b06000   (   816 KB)
[    0.000000]       .data : 0xffffff8008b06000 - 0xffffff8008ba2400   (   625 KB)
[    0.000000]        .bss : 0xffffff8008ba2400 - 0xffffff8008bdf738   (   245 KB)
[    0.000000]     vmemmap : 0xffffffbdc0000000 - 0xffffffbfc0000000   (     8 GB maximum)
[    0.000000]               0xffffffbdc0000000 - 0xffffffbdc8000000   (   128 MB actual)
[    0.000000]     fixed   : 0xffffffbffe7fd000 - 0xffffffbffec00000   (  4108 KB)
[    0.000000]     PCI I/O : 0xffffffbffee00000 - 0xffffffbfffe00000   (    16 MB)
[    0.000000]     memory  : 0xffffffc000000000 - 0xffffffc200000000   (  8192 MB)

Before,

[    0.000000] Virtual kernel memory layout:
[    0.000000]     modules : 0xffffff8000000000 - 0xffffff8008000000   (   128 MB)
[    0.000000]     vmalloc : 0xffffff8008000000 - 0xffffffbdbfff0000   (   246 GB)
[    0.000000]       .text : 0xffffff8008080000 - 0xffffff8008753000   (  6988 KB)
    .rodata : 0xffffff8008753000 - 0xffffff8008a3a000   (  2972 KB)
      .init : 0xffffff8008a3a000 - 0xffffff8008b06000   (   816 KB)
      .data : 0xffffff8008b06000 - 0xffffff8008ba2400   (   625 KB)
[    0.000000]     vmemmap : 0xffffffbdc0000000 - 0xffffffbfc0000000   (     8 GB maximum)
              0xffffffbdc0000000 - 0xffffffbdc8000000   (   128 MB actual)
[    0.000000]     fixed   : 0xffffffbffe7fd000 - 0xffffffbffec00000   (  4108 KB)
[    0.000000]     PCI I/O : 0xffffffbffee00000 - 0xffffffbfffe00000   (    16 MB)
[    0.000000]     memory  : 0xffffffc000000000 - 0xffffffc200000000   (  8192 MB)

 arch/arm64/mm/init.c | 32 +++++++++++++++++++++-----------
 1 file changed, 21 insertions(+), 11 deletions(-)

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index ea989d8..c6bcaa7 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -345,6 +345,9 @@ static void __init free_unused_memmap(void)
  */
 void __init mem_init(void)
 {
+	/* kernel exception vectors, 16 entries and each one with 128bytes */
+	extern char vectors[];
+
 	swiotlb_init(1);
 
 	set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
@@ -363,34 +366,41 @@ void __init mem_init(void)
 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
 
 	pr_notice("Virtual kernel memory layout:\n");
+	pr_cont("     vector : 0x%p - 0x%p   (%6ld KB)\n",
+		MLK(vectors, vectors + 0x780));
 #ifdef CONFIG_KASAN
 	pr_cont("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
 		MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
 #endif
+#ifdef CONFIG_MODULES
 	pr_cont("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
 		MLM(MODULES_VADDR, MODULES_END));
+#endif
 	pr_cont("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
 		MLG(VMALLOC_START, VMALLOC_END));
-	pr_cont("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n"
-		"    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n"
-		"      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n"
-		"      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
-		MLK_ROUNDUP(_text, __start_rodata),
-		MLK_ROUNDUP(__start_rodata, _etext),
-		MLK_ROUNDUP(__init_begin, __init_end),
+	pr_cont("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n",
+		MLK_ROUNDUP(_text, __start_rodata));
+	pr_cont("    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n",
+		MLK_ROUNDUP(__start_rodata, _etext));
+	pr_cont("      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n",
+		MLK_ROUNDUP(__init_begin, __init_end));
+	pr_cont("      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
 		MLK_ROUNDUP(_sdata, _edata));
+	pr_cont("       .bss : 0x%p" " - 0x%p" "   (%6ld KB)\n",
+		MLK_ROUNDUP(__bss_start, __bss_stop));
 #ifdef CONFIG_SPARSEMEM_VMEMMAP
-	pr_cont("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n"
-		"              0x%16lx - 0x%16lx   (%6ld MB actual)\n",
-		MLG(VMEMMAP_START,
-		    VMEMMAP_START + VMEMMAP_SIZE),
+	pr_cont("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
+		MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
+	pr_cont("              0x%16lx - 0x%16lx   (%6ld MB actual)\n",
 		MLM((unsigned long)phys_to_page(memblock_start_of_DRAM()),
 		    (unsigned long)virt_to_page(high_memory)));
 #endif
 	pr_cont("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
 		MLK(FIXADDR_START, FIXADDR_TOP));
+#ifdef CONFIG_PCI
 	pr_cont("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
 		MLM(PCI_IO_START, PCI_IO_END));
+#endif
 	pr_cont("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
 		MLM(__phys_to_virt(memblock_start_of_DRAM()),
 		    (unsigned long)high_memory));
-- 
2.6.0.GIT