From 75b7892b63107b38b27783672a9482bf08c2511d Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Thu, 14 Apr 2016 11:18:57 -0700 Subject: [PATCH] Revert "x86: remove the kernel code/data/bss resources from /proc/iomem" This reverts commit 17db9a4b4a5965a6e8bafcfb9b48d289f805ffa6. Sadly, my hope that nobody would actually use the special kernel entries in /proc/iomem were dashed by kexec. Which reads /proc/iomem explicitly to find the kernel base address. Nasty. Anyway, that means we can't do the sane and simple thing and just remove the entries, and we'll instead have to mask them out based on permissions. Reported-by: Zhengyu Zhang Reported-by: Dave Young Reported-by: Freeman Zhang Reported-by: Emrah Demir Reported-by: Baoquan He Signed-off-by: Linus Torvalds --- arch/x86/kernel/setup.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 319b08a5b6ed3..2367ae07eb76d 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -146,6 +146,31 @@ 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 = { @@ -924,6 +949,13 @@ 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); @@ -987,6 +1019,11 @@ 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 -- 2.39.5