diff options
-rw-r--r-- | arch/i386/kernel/vmlinux.lds.S | 4 | ||||
-rw-r--r-- | arch/i386/mm/init.c | 25 | ||||
-rw-r--r-- | arch/x86_64/kernel/head.S | 1 | ||||
-rw-r--r-- | arch/x86_64/kernel/vmlinux.lds.S | 5 | ||||
-rw-r--r-- | arch/x86_64/mm/init.c | 25 | ||||
-rw-r--r-- | include/linux/poison.h | 3 |
6 files changed, 40 insertions, 23 deletions
diff --git a/arch/i386/kernel/vmlinux.lds.S b/arch/i386/kernel/vmlinux.lds.S index 6f38f818380..f4ec7223183 100644 --- a/arch/i386/kernel/vmlinux.lds.S +++ b/arch/i386/kernel/vmlinux.lds.S @@ -61,8 +61,6 @@ SECTIONS __stop___ex_table = .; } - RODATA - BUG_TABLE . = ALIGN(4); @@ -72,6 +70,8 @@ SECTIONS __tracedata_end = .; } + RODATA + /* writeable */ . = ALIGN(4096); .data : AT(ADDR(.data) - LOAD_OFFSET) { /* Data */ diff --git a/arch/i386/mm/init.c b/arch/i386/mm/init.c index 23be1b0aafa..bd5ef371850 100644 --- a/arch/i386/mm/init.c +++ b/arch/i386/mm/init.c @@ -22,6 +22,7 @@ #include <linux/init.h> #include <linux/highmem.h> #include <linux/pagemap.h> +#include <linux/pfn.h> #include <linux/poison.h> #include <linux/bootmem.h> #include <linux/slab.h> @@ -751,13 +752,25 @@ static int noinline do_test_wp_bit(void) void mark_rodata_ro(void) { - unsigned long addr = (unsigned long)__start_rodata; + unsigned long start = PFN_ALIGN(_text); + unsigned long size = PFN_ALIGN(_etext) - start; - for (; addr < (unsigned long)__end_rodata; addr += PAGE_SIZE) - change_page_attr(virt_to_page(addr), 1, PAGE_KERNEL_RO); +#ifdef CONFIG_HOTPLUG_CPU + /* It must still be possible to apply SMP alternatives. */ + if (num_possible_cpus() <= 1) +#endif + { + change_page_attr(virt_to_page(start), + size >> PAGE_SHIFT, PAGE_KERNEL_RX); + printk("Write protecting the kernel text: %luk\n", size >> 10); + } - printk("Write protecting the kernel read-only data: %uk\n", - (__end_rodata - __start_rodata) >> 10); + start += size; + size = (unsigned long)__end_rodata - start; + change_page_attr(virt_to_page(start), + size >> PAGE_SHIFT, PAGE_KERNEL_RO); + printk("Write protecting the kernel read-only data: %luk\n", + size >> 10); /* * change_page_attr() requires a global_flush_tlb() call after it. @@ -781,7 +794,7 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end) __free_page(page); totalram_pages++; } - printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); + printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10); } void free_initmem(void) diff --git a/arch/x86_64/kernel/head.S b/arch/x86_64/kernel/head.S index 36aa98a6d15..fd9fdfdd143 100644 --- a/arch/x86_64/kernel/head.S +++ b/arch/x86_64/kernel/head.S @@ -280,7 +280,6 @@ early_idt_ripmsg: .balign PAGE_SIZE ENTRY(stext) -ENTRY(_stext) #define NEXT_PAGE(name) \ .balign PAGE_SIZE; \ diff --git a/arch/x86_64/kernel/vmlinux.lds.S b/arch/x86_64/kernel/vmlinux.lds.S index 5176ecf006e..3bdeb88d28f 100644 --- a/arch/x86_64/kernel/vmlinux.lds.S +++ b/arch/x86_64/kernel/vmlinux.lds.S @@ -29,6 +29,7 @@ SECTIONS .text : AT(ADDR(.text) - LOAD_OFFSET) { /* First the code that has to be first for bootstrapping */ *(.bootstrap.text) + _stext = .; /* Then all the functions that are "hot" in profiles, to group them onto the same hugetlb entry */ #include "functionlist" @@ -50,10 +51,10 @@ SECTIONS __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) { *(__ex_table) } __stop___ex_table = .; - RODATA - BUG_TABLE + RODATA + . = ALIGN(PAGE_SIZE); /* Align data segment to page size boundary */ /* Data */ .data : AT(ADDR(.data) - LOAD_OFFSET) { diff --git a/arch/x86_64/mm/init.c b/arch/x86_64/mm/init.c index 69e22d3c923..e3134bc9a4f 100644 --- a/arch/x86_64/mm/init.c +++ b/arch/x86_64/mm/init.c @@ -22,6 +22,7 @@ #include <linux/bootmem.h> #include <linux/proc_fs.h> #include <linux/pci.h> +#include <linux/pfn.h> #include <linux/poison.h> #include <linux/dma-mapping.h> #include <linux/module.h> @@ -563,21 +564,23 @@ void free_init_pages(char *what, unsigned long begin, unsigned long end) if (begin >= end) return; - printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10); + printk(KERN_INFO "Freeing %s: %luk freed\n", what, (end - begin) >> 10); for (addr = begin; addr < end; addr += PAGE_SIZE) { struct page *page = pfn_to_page(addr >> PAGE_SHIFT); ClearPageReserved(page); init_page_count(page); memset(page_address(page), POISON_FREE_INITMEM, PAGE_SIZE); + if (addr >= __START_KERNEL_map) + change_page_attr_addr(addr, 1, __pgprot(0)); __free_page(page); totalram_pages++; } + if (addr > __START_KERNEL_map) + global_flush_tlb(); } void free_initmem(void) { - memset(__initdata_begin, POISON_FREE_INITDATA, - __initdata_end - __initdata_begin); free_init_pages("unused kernel memory", __pa_symbol(&__init_begin), __pa_symbol(&__init_end)); @@ -587,14 +590,18 @@ void free_initmem(void) void mark_rodata_ro(void) { - unsigned long addr = (unsigned long)__va(__pa_symbol(&__start_rodata)); - unsigned long end = (unsigned long)__va(__pa_symbol(&__end_rodata)); + unsigned long start = PFN_ALIGN(__va(__pa_symbol(&_stext))), size; - for (; addr < end; addr += PAGE_SIZE) - change_page_attr_addr(addr, 1, PAGE_KERNEL_RO); +#ifdef CONFIG_HOTPLUG_CPU + /* It must still be possible to apply SMP alternatives. */ + if (num_possible_cpus() > 1) + start = PFN_ALIGN(__va(__pa_symbol(&_etext))); +#endif + size = (unsigned long)__va(__pa_symbol(&__end_rodata)) - start; + change_page_attr_addr(start, size >> PAGE_SHIFT, PAGE_KERNEL_RO); - printk ("Write protecting the kernel read-only data: %luk\n", - (__end_rodata - __start_rodata) >> 10); + printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n", + size >> 10); /* * change_page_attr_addr() requires a global_flush_tlb() call after it. diff --git a/include/linux/poison.h b/include/linux/poison.h index 3e628f990fd..89580b76495 100644 --- a/include/linux/poison.h +++ b/include/linux/poison.h @@ -26,9 +26,6 @@ /********** arch/$ARCH/mm/init.c **********/ #define POISON_FREE_INITMEM 0xcc -/********** arch/x86_64/mm/init.c **********/ -#define POISON_FREE_INITDATA 0xba - /********** arch/ia64/hp/common/sba_iommu.c **********/ /* * arch/ia64/hp/common/sba_iommu.c uses a 16-byte poison string with a |