x86: remove the kernel code/data/bss resources from /proc/iomem
authorLinus Torvalds <torvalds@linux-foundation.org>
Wed, 6 Apr 2016 20:45:07 +0000 (13:45 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 6 Apr 2016 20:45:07 +0000 (13:45 -0700)
Let's see if anybody even notices.  I doubt anybody uses this, and it
does expose addresses that should be randomized, so let's just remove
the code.  It's old and traditional, and it used to be cute, but we
should have removed this long ago.

If it turns out anybody notices and this breaks something, we'll have to
revert this, and maybe we'll end up using other approaches instead
(using %pK or similar).  But removing unnecessary code is always the
preferred option.

Noted-by: Emrah Demir <ed@abdsec.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/x86/kernel/setup.c

index 2367ae0..319b08a 100644 (file)
@@ -146,31 +146,6 @@ int default_check_phys_apicid_present(int phys_apicid)
 
 struct boot_params boot_params;
 
-/*
- * Machine setup..
- */
-static struct resource data_resource = {
-       .name   = "Kernel data",
-       .start  = 0,
-       .end    = 0,
-       .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
-};
-
-static struct resource code_resource = {
-       .name   = "Kernel code",
-       .start  = 0,
-       .end    = 0,
-       .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
-};
-
-static struct resource bss_resource = {
-       .name   = "Kernel bss",
-       .start  = 0,
-       .end    = 0,
-       .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
-};
-
-
 #ifdef CONFIG_X86_32
 /* cpu data as detected by the assembly code in head.S */
 struct cpuinfo_x86 new_cpu_data = {
@@ -949,13 +924,6 @@ void __init setup_arch(char **cmdline_p)
 
        mpx_mm_init(&init_mm);
 
-       code_resource.start = __pa_symbol(_text);
-       code_resource.end = __pa_symbol(_etext)-1;
-       data_resource.start = __pa_symbol(_etext);
-       data_resource.end = __pa_symbol(_edata)-1;
-       bss_resource.start = __pa_symbol(__bss_start);
-       bss_resource.end = __pa_symbol(__bss_stop)-1;
-
 #ifdef CONFIG_CMDLINE_BOOL
 #ifdef CONFIG_CMDLINE_OVERRIDE
        strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
@@ -1019,11 +987,6 @@ void __init setup_arch(char **cmdline_p)
 
        x86_init.resources.probe_roms();
 
-       /* after parse_early_param, so could debug it */
-       insert_resource(&iomem_resource, &code_resource);
-       insert_resource(&iomem_resource, &data_resource);
-       insert_resource(&iomem_resource, &bss_resource);
-
        e820_add_kernel_range();
        trim_bios_range();
 #ifdef CONFIG_X86_32