[PATCH] arm64: Stop printing the virtual memory layout

[PATCH] arm64: Stop printing the virtual memory layout

[Laura Abbott]

Printing kernel addresses should be done in limited circumstances, mostly
for debugging purposes. Printing out the virtual memory layout at every
kernel bootup doesn't really fall into this category so delete the prints.
There are other ways to get the same information.

Signed-off-by: Laura Abbott <labbott@redhat.com>
---
Follow up to my previous proposal to switch all these to %px
---
 arch/arm64/mm/init.c | 43 -------------------------------------------
 1 file changed, 43 deletions(-)

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 5960bef0170d..672094ed7e07 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -599,49 +599,6 @@ void __init mem_init(void)
 
 	mem_init_print_info(NULL);
 
-#define MLK(b, t) b, t, ((t) - (b)) >> 10
-#define MLM(b, t) b, t, ((t) - (b)) >> 20
-#define MLG(b, t) b, t, ((t) - (b)) >> 30
-#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
-
-	pr_notice("Virtual kernel memory layout:\n");
-#ifdef CONFIG_KASAN
-	pr_notice("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
-		MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
-#endif
-	pr_notice("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
-		MLM(MODULES_VADDR, MODULES_END));
-	pr_notice("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
-		MLG(VMALLOC_START, VMALLOC_END));
-	pr_notice("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n",
-		MLK_ROUNDUP(_text, _etext));
-	pr_notice("    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n",
-		MLK_ROUNDUP(__start_rodata, __init_begin));
-	pr_notice("      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n",
-		MLK_ROUNDUP(__init_begin, __init_end));
-	pr_notice("      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
-		MLK_ROUNDUP(_sdata, _edata));
-	pr_notice("       .bss : 0x%p" " - 0x%p" "   (%6ld KB)\n",
-		MLK_ROUNDUP(__bss_start, __bss_stop));
-	pr_notice("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
-		MLK(FIXADDR_START, FIXADDR_TOP));
-	pr_notice("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
-		MLM(PCI_IO_START, PCI_IO_END));
-#ifdef CONFIG_SPARSEMEM_VMEMMAP
-	pr_notice("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
-		MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
-	pr_notice("              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_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
-		MLM(__phys_to_virt(memblock_start_of_DRAM()),
-		    (unsigned long)high_memory));
-
-#undef MLK
-#undef MLM
-#undef MLK_ROUNDUP
-
 	/*
 	 * Check boundaries twice: Some fundamental inconsistencies can be
 	 * detected at build time already.
-- 
2.14.3

[PATCH] arm64: Stop printing the virtual memory layout

[Laura Abbott]

Printing kernel addresses should be done in limited circumstances, mostly
for debugging purposes. Printing out the virtual memory layout at every
kernel bootup doesn't really fall into this category so delete the prints.
There are other ways to get the same information.

Signed-off-by: Laura Abbott <labbott@redhat.com>
---
Follow up to my previous proposal to switch all these to %px
---
 arch/arm64/mm/init.c | 43 -------------------------------------------
 1 file changed, 43 deletions(-)

diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
index 5960bef0170d..672094ed7e07 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -599,49 +599,6 @@ void __init mem_init(void)
 
 	mem_init_print_info(NULL);
 
-#define MLK(b, t) b, t, ((t) - (b)) >> 10
-#define MLM(b, t) b, t, ((t) - (b)) >> 20
-#define MLG(b, t) b, t, ((t) - (b)) >> 30
-#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
-
-	pr_notice("Virtual kernel memory layout:\n");
-#ifdef CONFIG_KASAN
-	pr_notice("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
-		MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
-#endif
-	pr_notice("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
-		MLM(MODULES_VADDR, MODULES_END));
-	pr_notice("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
-		MLG(VMALLOC_START, VMALLOC_END));
-	pr_notice("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n",
-		MLK_ROUNDUP(_text, _etext));
-	pr_notice("    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n",
-		MLK_ROUNDUP(__start_rodata, __init_begin));
-	pr_notice("      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n",
-		MLK_ROUNDUP(__init_begin, __init_end));
-	pr_notice("      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
-		MLK_ROUNDUP(_sdata, _edata));
-	pr_notice("       .bss : 0x%p" " - 0x%p" "   (%6ld KB)\n",
-		MLK_ROUNDUP(__bss_start, __bss_stop));
-	pr_notice("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
-		MLK(FIXADDR_START, FIXADDR_TOP));
-	pr_notice("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
-		MLM(PCI_IO_START, PCI_IO_END));
-#ifdef CONFIG_SPARSEMEM_VMEMMAP
-	pr_notice("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
-		MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
-	pr_notice("              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_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
-		MLM(__phys_to_virt(memblock_start_of_DRAM()),
-		    (unsigned long)high_memory));
-
-#undef MLK
-#undef MLM
-#undef MLK_ROUNDUP
-
 	/*
 	 * Check boundaries twice: Some fundamental inconsistencies can be
 	 * detected at build time already.
-- 
2.14.3

Re: [PATCH] arm64: Stop printing the virtual memory layout

[Kees Cook]

On Tue, Dec 19, 2017 at 11:28 AM, Laura Abbott <labbott@redhat.com> wrote:
> Printing kernel addresses should be done in limited circumstances, mostly
> for debugging purposes. Printing out the virtual memory layout at every
> kernel bootup doesn't really fall into this category so delete the prints.
> There are other ways to get the same information.

In looking at this patch, I wonder: is there anything listed here that
is _missing_ from CONFIG_PTDUMP? I would expect all of these to
already be listed there, but I thought I'd ask...

Regardless:

Acked-by: Kees Cook <keescook@chromium.org>

-Kees

>
> Signed-off-by: Laura Abbott <labbott@redhat.com>
> ---
> Follow up to my previous proposal to switch all these to %px
> ---
>  arch/arm64/mm/init.c | 43 -------------------------------------------
>  1 file changed, 43 deletions(-)
>
> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> index 5960bef0170d..672094ed7e07 100644
> --- a/arch/arm64/mm/init.c
> +++ b/arch/arm64/mm/init.c
> @@ -599,49 +599,6 @@ void __init mem_init(void)
>
>         mem_init_print_info(NULL);
>
> -#define MLK(b, t) b, t, ((t) - (b)) >> 10
> -#define MLM(b, t) b, t, ((t) - (b)) >> 20
> -#define MLG(b, t) b, t, ((t) - (b)) >> 30
> -#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
> -
> -       pr_notice("Virtual kernel memory layout:\n");
> -#ifdef CONFIG_KASAN
> -       pr_notice("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
> -               MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
> -#endif
> -       pr_notice("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
> -               MLM(MODULES_VADDR, MODULES_END));
> -       pr_notice("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
> -               MLG(VMALLOC_START, VMALLOC_END));
> -       pr_notice("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -               MLK_ROUNDUP(_text, _etext));
> -       pr_notice("    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -               MLK_ROUNDUP(__start_rodata, __init_begin));
> -       pr_notice("      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -               MLK_ROUNDUP(__init_begin, __init_end));
> -       pr_notice("      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -               MLK_ROUNDUP(_sdata, _edata));
> -       pr_notice("       .bss : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -               MLK_ROUNDUP(__bss_start, __bss_stop));
> -       pr_notice("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
> -               MLK(FIXADDR_START, FIXADDR_TOP));
> -       pr_notice("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
> -               MLM(PCI_IO_START, PCI_IO_END));
> -#ifdef CONFIG_SPARSEMEM_VMEMMAP
> -       pr_notice("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
> -               MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
> -       pr_notice("              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_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
> -               MLM(__phys_to_virt(memblock_start_of_DRAM()),
> -                   (unsigned long)high_memory));
> -
> -#undef MLK
> -#undef MLM
> -#undef MLK_ROUNDUP
> -
>         /*
>          * Check boundaries twice: Some fundamental inconsistencies can be
>          * detected at build time already.
> --
> 2.14.3
>



-- 
Kees Cook
Pixel Security

[PATCH] arm64: Stop printing the virtual memory layout

[Kees Cook]

On Tue, Dec 19, 2017 at 11:28 AM, Laura Abbott <labbott@redhat.com> wrote:
> Printing kernel addresses should be done in limited circumstances, mostly
> for debugging purposes. Printing out the virtual memory layout at every
> kernel bootup doesn't really fall into this category so delete the prints.
> There are other ways to get the same information.

In looking at this patch, I wonder: is there anything listed here that
is _missing_ from CONFIG_PTDUMP? I would expect all of these to
already be listed there, but I thought I'd ask...

Regardless:

Acked-by: Kees Cook <keescook@chromium.org>

-Kees

>
> Signed-off-by: Laura Abbott <labbott@redhat.com>
> ---
> Follow up to my previous proposal to switch all these to %px
> ---
>  arch/arm64/mm/init.c | 43 -------------------------------------------
>  1 file changed, 43 deletions(-)
>
> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> index 5960bef0170d..672094ed7e07 100644
> --- a/arch/arm64/mm/init.c
> +++ b/arch/arm64/mm/init.c
> @@ -599,49 +599,6 @@ void __init mem_init(void)
>
>         mem_init_print_info(NULL);
>
> -#define MLK(b, t) b, t, ((t) - (b)) >> 10
> -#define MLM(b, t) b, t, ((t) - (b)) >> 20
> -#define MLG(b, t) b, t, ((t) - (b)) >> 30
> -#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
> -
> -       pr_notice("Virtual kernel memory layout:\n");
> -#ifdef CONFIG_KASAN
> -       pr_notice("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
> -               MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
> -#endif
> -       pr_notice("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
> -               MLM(MODULES_VADDR, MODULES_END));
> -       pr_notice("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
> -               MLG(VMALLOC_START, VMALLOC_END));
> -       pr_notice("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -               MLK_ROUNDUP(_text, _etext));
> -       pr_notice("    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -               MLK_ROUNDUP(__start_rodata, __init_begin));
> -       pr_notice("      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -               MLK_ROUNDUP(__init_begin, __init_end));
> -       pr_notice("      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -               MLK_ROUNDUP(_sdata, _edata));
> -       pr_notice("       .bss : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -               MLK_ROUNDUP(__bss_start, __bss_stop));
> -       pr_notice("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
> -               MLK(FIXADDR_START, FIXADDR_TOP));
> -       pr_notice("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
> -               MLM(PCI_IO_START, PCI_IO_END));
> -#ifdef CONFIG_SPARSEMEM_VMEMMAP
> -       pr_notice("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
> -               MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
> -       pr_notice("              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_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
> -               MLM(__phys_to_virt(memblock_start_of_DRAM()),
> -                   (unsigned long)high_memory));
> -
> -#undef MLK
> -#undef MLM
> -#undef MLK_ROUNDUP
> -
>         /*
>          * Check boundaries twice: Some fundamental inconsistencies can be
>          * detected at build time already.
> --
> 2.14.3
>



-- 
Kees Cook
Pixel Security

Re: [PATCH] arm64: Stop printing the virtual memory layout

[Laura Abbott]

On 12/19/2017 01:04 PM, Kees Cook wrote:
> On Tue, Dec 19, 2017 at 11:28 AM, Laura Abbott <labbott@redhat.com> wrote:
>> Printing kernel addresses should be done in limited circumstances, mostly
>> for debugging purposes. Printing out the virtual memory layout at every
>> kernel bootup doesn't really fall into this category so delete the prints.
>> There are other ways to get the same information.
> 
> In looking at this patch, I wonder: is there anything listed here that
> is _missing_ from CONFIG_PTDUMP? I would expect all of these to
> already be listed there, but I thought I'd ask...
> 

It doesn't print the .text etc. but those can be calculated other ways.

> Regardless:
> 
> Acked-by: Kees Cook <keescook@chromium.org>
> 
> -Kees
> 
>>
>> Signed-off-by: Laura Abbott <labbott@redhat.com>
>> ---
>> Follow up to my previous proposal to switch all these to %px
>> ---
>>   arch/arm64/mm/init.c | 43 -------------------------------------------
>>   1 file changed, 43 deletions(-)
>>
>> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
>> index 5960bef0170d..672094ed7e07 100644
>> --- a/arch/arm64/mm/init.c
>> +++ b/arch/arm64/mm/init.c
>> @@ -599,49 +599,6 @@ void __init mem_init(void)
>>
>>          mem_init_print_info(NULL);
>>
>> -#define MLK(b, t) b, t, ((t) - (b)) >> 10
>> -#define MLM(b, t) b, t, ((t) - (b)) >> 20
>> -#define MLG(b, t) b, t, ((t) - (b)) >> 30
>> -#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
>> -
>> -       pr_notice("Virtual kernel memory layout:\n");
>> -#ifdef CONFIG_KASAN
>> -       pr_notice("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
>> -               MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
>> -#endif
>> -       pr_notice("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
>> -               MLM(MODULES_VADDR, MODULES_END));
>> -       pr_notice("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
>> -               MLG(VMALLOC_START, VMALLOC_END));
>> -       pr_notice("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(_text, _etext));
>> -       pr_notice("    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(__start_rodata, __init_begin));
>> -       pr_notice("      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(__init_begin, __init_end));
>> -       pr_notice("      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(_sdata, _edata));
>> -       pr_notice("       .bss : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(__bss_start, __bss_stop));
>> -       pr_notice("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
>> -               MLK(FIXADDR_START, FIXADDR_TOP));
>> -       pr_notice("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
>> -               MLM(PCI_IO_START, PCI_IO_END));
>> -#ifdef CONFIG_SPARSEMEM_VMEMMAP
>> -       pr_notice("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
>> -               MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
>> -       pr_notice("              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_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
>> -               MLM(__phys_to_virt(memblock_start_of_DRAM()),
>> -                   (unsigned long)high_memory));
>> -
>> -#undef MLK
>> -#undef MLM
>> -#undef MLK_ROUNDUP
>> -
>>          /*
>>           * Check boundaries twice: Some fundamental inconsistencies can be
>>           * detected at build time already.
>> --
>> 2.14.3
>>
> 
> 
> 

[PATCH] arm64: Stop printing the virtual memory layout

[Laura Abbott]

On 12/19/2017 01:04 PM, Kees Cook wrote:
> On Tue, Dec 19, 2017 at 11:28 AM, Laura Abbott <labbott@redhat.com> wrote:
>> Printing kernel addresses should be done in limited circumstances, mostly
>> for debugging purposes. Printing out the virtual memory layout at every
>> kernel bootup doesn't really fall into this category so delete the prints.
>> There are other ways to get the same information.
> 
> In looking at this patch, I wonder: is there anything listed here that
> is _missing_ from CONFIG_PTDUMP? I would expect all of these to
> already be listed there, but I thought I'd ask...
> 

It doesn't print the .text etc. but those can be calculated other ways.

> Regardless:
> 
> Acked-by: Kees Cook <keescook@chromium.org>
> 
> -Kees
> 
>>
>> Signed-off-by: Laura Abbott <labbott@redhat.com>
>> ---
>> Follow up to my previous proposal to switch all these to %px
>> ---
>>   arch/arm64/mm/init.c | 43 -------------------------------------------
>>   1 file changed, 43 deletions(-)
>>
>> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
>> index 5960bef0170d..672094ed7e07 100644
>> --- a/arch/arm64/mm/init.c
>> +++ b/arch/arm64/mm/init.c
>> @@ -599,49 +599,6 @@ void __init mem_init(void)
>>
>>          mem_init_print_info(NULL);
>>
>> -#define MLK(b, t) b, t, ((t) - (b)) >> 10
>> -#define MLM(b, t) b, t, ((t) - (b)) >> 20
>> -#define MLG(b, t) b, t, ((t) - (b)) >> 30
>> -#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
>> -
>> -       pr_notice("Virtual kernel memory layout:\n");
>> -#ifdef CONFIG_KASAN
>> -       pr_notice("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
>> -               MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
>> -#endif
>> -       pr_notice("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
>> -               MLM(MODULES_VADDR, MODULES_END));
>> -       pr_notice("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
>> -               MLG(VMALLOC_START, VMALLOC_END));
>> -       pr_notice("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(_text, _etext));
>> -       pr_notice("    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(__start_rodata, __init_begin));
>> -       pr_notice("      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(__init_begin, __init_end));
>> -       pr_notice("      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(_sdata, _edata));
>> -       pr_notice("       .bss : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(__bss_start, __bss_stop));
>> -       pr_notice("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
>> -               MLK(FIXADDR_START, FIXADDR_TOP));
>> -       pr_notice("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
>> -               MLM(PCI_IO_START, PCI_IO_END));
>> -#ifdef CONFIG_SPARSEMEM_VMEMMAP
>> -       pr_notice("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
>> -               MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
>> -       pr_notice("              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_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
>> -               MLM(__phys_to_virt(memblock_start_of_DRAM()),
>> -                   (unsigned long)high_memory));
>> -
>> -#undef MLK
>> -#undef MLM
>> -#undef MLK_ROUNDUP
>> -
>>          /*
>>           * Check boundaries twice: Some fundamental inconsistencies can be
>>           * detected at build time already.
>> --
>> 2.14.3
>>
> 
> 
> 

Re: [PATCH] arm64: Stop printing the virtual memory layout

[Kees Cook]

On Tue, Dec 19, 2017 at 1:04 PM, Kees Cook <keescook@chromium.org> wrote:
> On Tue, Dec 19, 2017 at 11:28 AM, Laura Abbott <labbott@redhat.com> wrote:
>> Printing kernel addresses should be done in limited circumstances, mostly
>> for debugging purposes. Printing out the virtual memory layout at every
>> kernel bootup doesn't really fall into this category so delete the prints.
>> There are other ways to get the same information.
>
> In looking at this patch, I wonder: is there anything listed here that
> is _missing_ from CONFIG_PTDUMP? I would expect all of these to
> already be listed there, but I thought I'd ask...
>
> Regardless:
>
> Acked-by: Kees Cook <keescook@chromium.org>
>
> -Kees
>
>>
>> Signed-off-by: Laura Abbott <labbott@redhat.com>

Did this patch get picked up? I don't see it in -next.

-Kees

>> ---
>> Follow up to my previous proposal to switch all these to %px
>> ---
>>  arch/arm64/mm/init.c | 43 -------------------------------------------
>>  1 file changed, 43 deletions(-)
>>
>> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
>> index 5960bef0170d..672094ed7e07 100644
>> --- a/arch/arm64/mm/init.c
>> +++ b/arch/arm64/mm/init.c
>> @@ -599,49 +599,6 @@ void __init mem_init(void)
>>
>>         mem_init_print_info(NULL);
>>
>> -#define MLK(b, t) b, t, ((t) - (b)) >> 10
>> -#define MLM(b, t) b, t, ((t) - (b)) >> 20
>> -#define MLG(b, t) b, t, ((t) - (b)) >> 30
>> -#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
>> -
>> -       pr_notice("Virtual kernel memory layout:\n");
>> -#ifdef CONFIG_KASAN
>> -       pr_notice("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
>> -               MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
>> -#endif
>> -       pr_notice("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
>> -               MLM(MODULES_VADDR, MODULES_END));
>> -       pr_notice("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
>> -               MLG(VMALLOC_START, VMALLOC_END));
>> -       pr_notice("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(_text, _etext));
>> -       pr_notice("    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(__start_rodata, __init_begin));
>> -       pr_notice("      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(__init_begin, __init_end));
>> -       pr_notice("      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(_sdata, _edata));
>> -       pr_notice("       .bss : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(__bss_start, __bss_stop));
>> -       pr_notice("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
>> -               MLK(FIXADDR_START, FIXADDR_TOP));
>> -       pr_notice("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
>> -               MLM(PCI_IO_START, PCI_IO_END));
>> -#ifdef CONFIG_SPARSEMEM_VMEMMAP
>> -       pr_notice("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
>> -               MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
>> -       pr_notice("              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_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
>> -               MLM(__phys_to_virt(memblock_start_of_DRAM()),
>> -                   (unsigned long)high_memory));
>> -
>> -#undef MLK
>> -#undef MLM
>> -#undef MLK_ROUNDUP
>> -
>>         /*
>>          * Check boundaries twice: Some fundamental inconsistencies can be
>>          * detected at build time already.
>> --
>> 2.14.3
>>
>
>
>
> --
> Kees Cook
> Pixel Security

-- 
Kees Cook
Pixel Security

[PATCH] arm64: Stop printing the virtual memory layout

[Kees Cook]

On Tue, Dec 19, 2017 at 1:04 PM, Kees Cook <keescook@chromium.org> wrote:
> On Tue, Dec 19, 2017 at 11:28 AM, Laura Abbott <labbott@redhat.com> wrote:
>> Printing kernel addresses should be done in limited circumstances, mostly
>> for debugging purposes. Printing out the virtual memory layout at every
>> kernel bootup doesn't really fall into this category so delete the prints.
>> There are other ways to get the same information.
>
> In looking at this patch, I wonder: is there anything listed here that
> is _missing_ from CONFIG_PTDUMP? I would expect all of these to
> already be listed there, but I thought I'd ask...
>
> Regardless:
>
> Acked-by: Kees Cook <keescook@chromium.org>
>
> -Kees
>
>>
>> Signed-off-by: Laura Abbott <labbott@redhat.com>

Did this patch get picked up? I don't see it in -next.

-Kees

>> ---
>> Follow up to my previous proposal to switch all these to %px
>> ---
>>  arch/arm64/mm/init.c | 43 -------------------------------------------
>>  1 file changed, 43 deletions(-)
>>
>> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
>> index 5960bef0170d..672094ed7e07 100644
>> --- a/arch/arm64/mm/init.c
>> +++ b/arch/arm64/mm/init.c
>> @@ -599,49 +599,6 @@ void __init mem_init(void)
>>
>>         mem_init_print_info(NULL);
>>
>> -#define MLK(b, t) b, t, ((t) - (b)) >> 10
>> -#define MLM(b, t) b, t, ((t) - (b)) >> 20
>> -#define MLG(b, t) b, t, ((t) - (b)) >> 30
>> -#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
>> -
>> -       pr_notice("Virtual kernel memory layout:\n");
>> -#ifdef CONFIG_KASAN
>> -       pr_notice("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
>> -               MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
>> -#endif
>> -       pr_notice("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
>> -               MLM(MODULES_VADDR, MODULES_END));
>> -       pr_notice("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
>> -               MLG(VMALLOC_START, VMALLOC_END));
>> -       pr_notice("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(_text, _etext));
>> -       pr_notice("    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(__start_rodata, __init_begin));
>> -       pr_notice("      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(__init_begin, __init_end));
>> -       pr_notice("      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(_sdata, _edata));
>> -       pr_notice("       .bss : 0x%p" " - 0x%p" "   (%6ld KB)\n",
>> -               MLK_ROUNDUP(__bss_start, __bss_stop));
>> -       pr_notice("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
>> -               MLK(FIXADDR_START, FIXADDR_TOP));
>> -       pr_notice("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
>> -               MLM(PCI_IO_START, PCI_IO_END));
>> -#ifdef CONFIG_SPARSEMEM_VMEMMAP
>> -       pr_notice("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
>> -               MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
>> -       pr_notice("              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_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
>> -               MLM(__phys_to_virt(memblock_start_of_DRAM()),
>> -                   (unsigned long)high_memory));
>> -
>> -#undef MLK
>> -#undef MLM
>> -#undef MLK_ROUNDUP
>> -
>>         /*
>>          * Check boundaries twice: Some fundamental inconsistencies can be
>>          * detected at build time already.
>> --
>> 2.14.3
>>
>
>
>
> --
> Kees Cook
> Pixel Security

-- 
Kees Cook
Pixel Security

Re: [PATCH] arm64: Stop printing the virtual memory layout

[Catalin Marinas]

On Tue, Jan 09, 2018 at 03:02:12PM -0800, Kees Cook wrote:
> On Tue, Dec 19, 2017 at 1:04 PM, Kees Cook <keescook@chromium.org> wrote:
> > On Tue, Dec 19, 2017 at 11:28 AM, Laura Abbott <labbott@redhat.com> wrote:
> >> Printing kernel addresses should be done in limited circumstances, mostly
> >> for debugging purposes. Printing out the virtual memory layout at every
> >> kernel bootup doesn't really fall into this category so delete the prints.
> >> There are other ways to get the same information.
> >
> > In looking at this patch, I wonder: is there anything listed here that
> > is _missing_ from CONFIG_PTDUMP? I would expect all of these to
> > already be listed there, but I thought I'd ask...
> >
> > Regardless:
> >
> > Acked-by: Kees Cook <keescook@chromium.org>
> >
> > -Kees
> >
> >>
> >> Signed-off-by: Laura Abbott <labbott@redhat.com>
> 
> Did this patch get picked up? I don't see it in -next.

I queued it now, should appear soon.

Thanks.

-- 
Catalin

[PATCH] arm64: Stop printing the virtual memory layout

[Catalin Marinas]

On Tue, Jan 09, 2018 at 03:02:12PM -0800, Kees Cook wrote:
> On Tue, Dec 19, 2017 at 1:04 PM, Kees Cook <keescook@chromium.org> wrote:
> > On Tue, Dec 19, 2017 at 11:28 AM, Laura Abbott <labbott@redhat.com> wrote:
> >> Printing kernel addresses should be done in limited circumstances, mostly
> >> for debugging purposes. Printing out the virtual memory layout at every
> >> kernel bootup doesn't really fall into this category so delete the prints.
> >> There are other ways to get the same information.
> >
> > In looking at this patch, I wonder: is there anything listed here that
> > is _missing_ from CONFIG_PTDUMP? I would expect all of these to
> > already be listed there, but I thought I'd ask...
> >
> > Regardless:
> >
> > Acked-by: Kees Cook <keescook@chromium.org>
> >
> > -Kees
> >
> >>
> >> Signed-off-by: Laura Abbott <labbott@redhat.com>
> 
> Did this patch get picked up? I don't see it in -next.

I queued it now, should appear soon.

Thanks.

-- 
Catalin

Re: [PATCH] arm64: Stop printing the virtual memory layout

[Kees Cook]

On Mon, Jan 15, 2018 at 10:18 AM, Catalin Marinas
<catalin.marinas@arm.com> wrote:
> On Tue, Jan 09, 2018 at 03:02:12PM -0800, Kees Cook wrote:
>> On Tue, Dec 19, 2017 at 1:04 PM, Kees Cook <keescook@chromium.org> wrote:
>> > On Tue, Dec 19, 2017 at 11:28 AM, Laura Abbott <labbott@redhat.com> wrote:
>> >> Printing kernel addresses should be done in limited circumstances, mostly
>> >> for debugging purposes. Printing out the virtual memory layout at every
>> >> kernel bootup doesn't really fall into this category so delete the prints.
>> >> There are other ways to get the same information.
>> >
>> > In looking at this patch, I wonder: is there anything listed here that
>> > is _missing_ from CONFIG_PTDUMP? I would expect all of these to
>> > already be listed there, but I thought I'd ask...
>> >
>> > Regardless:
>> >
>> > Acked-by: Kees Cook <keescook@chromium.org>
>> >
>> > -Kees
>> >
>> >>
>> >> Signed-off-by: Laura Abbott <labbott@redhat.com>
>>
>> Did this patch get picked up? I don't see it in -next.
>
> I queued it now, should appear soon.

Great, thanks!

-Kees

-- 
Kees Cook
Pixel Security

[PATCH] arm64: Stop printing the virtual memory layout

[Kees Cook]

On Mon, Jan 15, 2018 at 10:18 AM, Catalin Marinas
<catalin.marinas@arm.com> wrote:
> On Tue, Jan 09, 2018 at 03:02:12PM -0800, Kees Cook wrote:
>> On Tue, Dec 19, 2017 at 1:04 PM, Kees Cook <keescook@chromium.org> wrote:
>> > On Tue, Dec 19, 2017 at 11:28 AM, Laura Abbott <labbott@redhat.com> wrote:
>> >> Printing kernel addresses should be done in limited circumstances, mostly
>> >> for debugging purposes. Printing out the virtual memory layout at every
>> >> kernel bootup doesn't really fall into this category so delete the prints.
>> >> There are other ways to get the same information.
>> >
>> > In looking at this patch, I wonder: is there anything listed here that
>> > is _missing_ from CONFIG_PTDUMP? I would expect all of these to
>> > already be listed there, but I thought I'd ask...
>> >
>> > Regardless:
>> >
>> > Acked-by: Kees Cook <keescook@chromium.org>
>> >
>> > -Kees
>> >
>> >>
>> >> Signed-off-by: Laura Abbott <labbott@redhat.com>
>>
>> Did this patch get picked up? I don't see it in -next.
>
> I queued it now, should appear soon.

Great, thanks!

-Kees

-- 
Kees Cook
Pixel Security

Re: [PATCH] arm64: Stop printing the virtual memory layout

[Florian Fainelli]

On 12/19/2017 11:28 AM, Laura Abbott wrote:
> Printing kernel addresses should be done in limited circumstances, mostly
> for debugging purposes. Printing out the virtual memory layout at every
> kernel bootup doesn't really fall into this category so delete the prints.
> There are other ways to get the same information.

This really has some value when debugging systems, could we possibly
just hide that behind an appropriate configuration option instead of
completely removing this?

> 
> Signed-off-by: Laura Abbott <labbott@redhat.com>
> ---
> Follow up to my previous proposal to switch all these to %px
> ---
>  arch/arm64/mm/init.c | 43 -------------------------------------------
>  1 file changed, 43 deletions(-)
> 
> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> index 5960bef0170d..672094ed7e07 100644
> --- a/arch/arm64/mm/init.c
> +++ b/arch/arm64/mm/init.c
> @@ -599,49 +599,6 @@ void __init mem_init(void)
>  
>  	mem_init_print_info(NULL);
>  
> -#define MLK(b, t) b, t, ((t) - (b)) >> 10
> -#define MLM(b, t) b, t, ((t) - (b)) >> 20
> -#define MLG(b, t) b, t, ((t) - (b)) >> 30
> -#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
> -
> -	pr_notice("Virtual kernel memory layout:\n");
> -#ifdef CONFIG_KASAN
> -	pr_notice("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
> -		MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
> -#endif
> -	pr_notice("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
> -		MLM(MODULES_VADDR, MODULES_END));
> -	pr_notice("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
> -		MLG(VMALLOC_START, VMALLOC_END));
> -	pr_notice("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -		MLK_ROUNDUP(_text, _etext));
> -	pr_notice("    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -		MLK_ROUNDUP(__start_rodata, __init_begin));
> -	pr_notice("      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -		MLK_ROUNDUP(__init_begin, __init_end));
> -	pr_notice("      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -		MLK_ROUNDUP(_sdata, _edata));
> -	pr_notice("       .bss : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -		MLK_ROUNDUP(__bss_start, __bss_stop));
> -	pr_notice("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
> -		MLK(FIXADDR_START, FIXADDR_TOP));
> -	pr_notice("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
> -		MLM(PCI_IO_START, PCI_IO_END));
> -#ifdef CONFIG_SPARSEMEM_VMEMMAP
> -	pr_notice("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
> -		MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
> -	pr_notice("              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_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
> -		MLM(__phys_to_virt(memblock_start_of_DRAM()),
> -		    (unsigned long)high_memory));
> -
> -#undef MLK
> -#undef MLM
> -#undef MLK_ROUNDUP
> -
>  	/*
>  	 * Check boundaries twice: Some fundamental inconsistencies can be
>  	 * detected at build time already.
> 


-- 
Florian

[PATCH] arm64: Stop printing the virtual memory layout

[Florian Fainelli]

On 12/19/2017 11:28 AM, Laura Abbott wrote:
> Printing kernel addresses should be done in limited circumstances, mostly
> for debugging purposes. Printing out the virtual memory layout at every
> kernel bootup doesn't really fall into this category so delete the prints.
> There are other ways to get the same information.

This really has some value when debugging systems, could we possibly
just hide that behind an appropriate configuration option instead of
completely removing this?

> 
> Signed-off-by: Laura Abbott <labbott@redhat.com>
> ---
> Follow up to my previous proposal to switch all these to %px
> ---
>  arch/arm64/mm/init.c | 43 -------------------------------------------
>  1 file changed, 43 deletions(-)
> 
> diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c
> index 5960bef0170d..672094ed7e07 100644
> --- a/arch/arm64/mm/init.c
> +++ b/arch/arm64/mm/init.c
> @@ -599,49 +599,6 @@ void __init mem_init(void)
>  
>  	mem_init_print_info(NULL);
>  
> -#define MLK(b, t) b, t, ((t) - (b)) >> 10
> -#define MLM(b, t) b, t, ((t) - (b)) >> 20
> -#define MLG(b, t) b, t, ((t) - (b)) >> 30
> -#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
> -
> -	pr_notice("Virtual kernel memory layout:\n");
> -#ifdef CONFIG_KASAN
> -	pr_notice("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
> -		MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
> -#endif
> -	pr_notice("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
> -		MLM(MODULES_VADDR, MODULES_END));
> -	pr_notice("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
> -		MLG(VMALLOC_START, VMALLOC_END));
> -	pr_notice("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -		MLK_ROUNDUP(_text, _etext));
> -	pr_notice("    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -		MLK_ROUNDUP(__start_rodata, __init_begin));
> -	pr_notice("      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -		MLK_ROUNDUP(__init_begin, __init_end));
> -	pr_notice("      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -		MLK_ROUNDUP(_sdata, _edata));
> -	pr_notice("       .bss : 0x%p" " - 0x%p" "   (%6ld KB)\n",
> -		MLK_ROUNDUP(__bss_start, __bss_stop));
> -	pr_notice("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
> -		MLK(FIXADDR_START, FIXADDR_TOP));
> -	pr_notice("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
> -		MLM(PCI_IO_START, PCI_IO_END));
> -#ifdef CONFIG_SPARSEMEM_VMEMMAP
> -	pr_notice("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
> -		MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
> -	pr_notice("              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_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
> -		MLM(__phys_to_virt(memblock_start_of_DRAM()),
> -		    (unsigned long)high_memory));
> -
> -#undef MLK
> -#undef MLM
> -#undef MLK_ROUNDUP
> -
>  	/*
>  	 * Check boundaries twice: Some fundamental inconsistencies can be
>  	 * detected at build time already.
> 


-- 
Florian

Re: [PATCH] arm64: Stop printing the virtual memory layout

[Russell King - ARM Linux]

On Thu, Jan 18, 2018 at 12:01:31PM -0800, Florian Fainelli wrote:
> On 12/19/2017 11:28 AM, Laura Abbott wrote:
> > Printing kernel addresses should be done in limited circumstances, mostly
> > for debugging purposes. Printing out the virtual memory layout at every
> > kernel bootup doesn't really fall into this category so delete the prints.
> > There are other ways to get the same information.
> 
> This really has some value when debugging systems, could we possibly
> just hide that behind an appropriate configuration option instead of
> completely removing this?

I've already ended up having to revert the vsprintf() change nobbling
%p for that very reason when debugging the BPF code.  It's easier to
do that while debugging than remember about the %px thing - and lets
face it, probably less error prone if it leaks out.

Otherwise we'll just end up with everyone spelling %p as %px in their
debug statements... or using %lx and casting to unsigned long.

So yes, I do think a Kconfig option (defaulting to obscuring kernel
addresses of course) would have been very sensible for this.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up
According to speedtest.net: 8.21Mbps down 510kbps up

[PATCH] arm64: Stop printing the virtual memory layout

[Russell King - ARM Linux]

On Thu, Jan 18, 2018 at 12:01:31PM -0800, Florian Fainelli wrote:
> On 12/19/2017 11:28 AM, Laura Abbott wrote:
> > Printing kernel addresses should be done in limited circumstances, mostly
> > for debugging purposes. Printing out the virtual memory layout at every
> > kernel bootup doesn't really fall into this category so delete the prints.
> > There are other ways to get the same information.
> 
> This really has some value when debugging systems, could we possibly
> just hide that behind an appropriate configuration option instead of
> completely removing this?

I've already ended up having to revert the vsprintf() change nobbling
%p for that very reason when debugging the BPF code.  It's easier to
do that while debugging than remember about the %px thing - and lets
face it, probably less error prone if it leaks out.

Otherwise we'll just end up with everyone spelling %p as %px in their
debug statements... or using %lx and casting to unsigned long.

So yes, I do think a Kconfig option (defaulting to obscuring kernel
addresses of course) would have been very sensible for this.

-- 
RMK's Patch system: http://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 8.8Mbps down 630kbps up
According to speedtest.net: 8.21Mbps down 510kbps up