linux/arch/s390/kernel/setup.c

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/*
* arch/s390/kernel/setup.c
*
* S390 version
* Copyright (C) IBM Corp. 1999,2010
* Author(s): Hartmut Penner (hp@de.ibm.com),
* Martin Schwidefsky (schwidefsky@de.ibm.com)
*
* Derived from "arch/i386/kernel/setup.c"
* Copyright (C) 1995, Linus Torvalds
*/
/*
* This file handles the architecture-dependent parts of initialization
*/
#define KMSG_COMPONENT "setup"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/tty.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/initrd.h>
#include <linux/bootmem.h>
#include <linux/root_dev.h>
#include <linux/console.h>
#include <linux/kernel_stat.h>
#include <linux/device.h>
#include <linux/notifier.h>
#include <linux/pfn.h>
#include <linux/ctype.h>
#include <linux/reboot.h>
#include <linux/topology.h>
#include <linux/ftrace.h>
#include <asm/ipl.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/smp.h>
#include <asm/mmu_context.h>
#include <asm/cpcmd.h>
#include <asm/lowcore.h>
#include <asm/irq.h>
#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/sections.h>
#include <asm/ebcdic.h>
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
#include <asm/compat.h>
#include <asm/kvm_virtio.h>
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
long psw_kernel_bits = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
long psw_user_bits = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
/*
* User copy operations.
*/
struct uaccess_ops uaccess;
EXPORT_SYMBOL(uaccess);
/*
* Machine setup..
*/
unsigned int console_mode = 0;
EXPORT_SYMBOL(console_mode);
unsigned int console_devno = -1;
EXPORT_SYMBOL(console_devno);
unsigned int console_irq = -1;
EXPORT_SYMBOL(console_irq);
unsigned long elf_hwcap = 0;
char elf_platform[ELF_PLATFORM_SIZE];
struct mem_chunk __initdata memory_chunk[MEMORY_CHUNKS];
int __initdata memory_end_set;
unsigned long __initdata memory_end;
/* An array with a pointer to the lowcore of every CPU. */
struct _lowcore *lowcore_ptr[NR_CPUS];
EXPORT_SYMBOL(lowcore_ptr);
/*
* This is set up by the setup-routine at boot-time
* for S390 need to find out, what we have to setup
* using address 0x10400 ...
*/
#include <asm/setup.h>
static struct resource code_resource = {
.name = "Kernel code",
.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
};
static struct resource data_resource = {
.name = "Kernel data",
.flags = IORESOURCE_BUSY | IORESOURCE_MEM,
};
/*
* condev= and conmode= setup parameter.
*/
static int __init condev_setup(char *str)
{
int vdev;
vdev = simple_strtoul(str, &str, 0);
if (vdev >= 0 && vdev < 65536) {
console_devno = vdev;
console_irq = -1;
}
return 1;
}
__setup("condev=", condev_setup);
static void __init set_preferred_console(void)
{
if (MACHINE_IS_KVM)
add_preferred_console("hvc", 0, NULL);
else if (CONSOLE_IS_3215 || CONSOLE_IS_SCLP)
add_preferred_console("ttyS", 0, NULL);
else if (CONSOLE_IS_3270)
add_preferred_console("tty3270", 0, NULL);
}
static int __init conmode_setup(char *str)
{
#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
if (strncmp(str, "hwc", 4) == 0 || strncmp(str, "sclp", 5) == 0)
SET_CONSOLE_SCLP;
#endif
#if defined(CONFIG_TN3215_CONSOLE)
if (strncmp(str, "3215", 5) == 0)
SET_CONSOLE_3215;
#endif
#if defined(CONFIG_TN3270_CONSOLE)
if (strncmp(str, "3270", 5) == 0)
SET_CONSOLE_3270;
#endif
set_preferred_console();
return 1;
}
__setup("conmode=", conmode_setup);
static void __init conmode_default(void)
{
char query_buffer[1024];
char *ptr;
if (MACHINE_IS_VM) {
cpcmd("QUERY CONSOLE", query_buffer, 1024, NULL);
console_devno = simple_strtoul(query_buffer + 5, NULL, 16);
ptr = strstr(query_buffer, "SUBCHANNEL =");
console_irq = simple_strtoul(ptr + 13, NULL, 16);
cpcmd("QUERY TERM", query_buffer, 1024, NULL);
ptr = strstr(query_buffer, "CONMODE");
/*
* Set the conmode to 3215 so that the device recognition
* will set the cu_type of the console to 3215. If the
* conmode is 3270 and we don't set it back then both
* 3215 and the 3270 driver will try to access the console
* device (3215 as console and 3270 as normal tty).
*/
cpcmd("TERM CONMODE 3215", NULL, 0, NULL);
if (ptr == NULL) {
#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
SET_CONSOLE_SCLP;
#endif
return;
}
if (strncmp(ptr + 8, "3270", 4) == 0) {
#if defined(CONFIG_TN3270_CONSOLE)
SET_CONSOLE_3270;
#elif defined(CONFIG_TN3215_CONSOLE)
SET_CONSOLE_3215;
#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
SET_CONSOLE_SCLP;
#endif
} else if (strncmp(ptr + 8, "3215", 4) == 0) {
#if defined(CONFIG_TN3215_CONSOLE)
SET_CONSOLE_3215;
#elif defined(CONFIG_TN3270_CONSOLE)
SET_CONSOLE_3270;
#elif defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
SET_CONSOLE_SCLP;
#endif
}
} else {
#if defined(CONFIG_SCLP_CONSOLE) || defined(CONFIG_SCLP_VT220_CONSOLE)
SET_CONSOLE_SCLP;
#endif
}
}
#ifdef CONFIG_ZFCPDUMP
static void __init setup_zfcpdump(unsigned int console_devno)
{
static char str[41];
if (ipl_info.type != IPL_TYPE_FCP_DUMP)
return;
if (console_devno != -1)
sprintf(str, " cio_ignore=all,!0.0.%04x,!0.0.%04x",
ipl_info.data.fcp.dev_id.devno, console_devno);
else
sprintf(str, " cio_ignore=all,!0.0.%04x",
ipl_info.data.fcp.dev_id.devno);
strcat(boot_command_line, str);
console_loglevel = 2;
}
#else
static inline void setup_zfcpdump(unsigned int console_devno) {}
#endif /* CONFIG_ZFCPDUMP */
/*
* Reboot, halt and power_off stubs. They just call _machine_restart,
* _machine_halt or _machine_power_off.
*/
void machine_restart(char *command)
{
[S390] magic sysrq: check for in_atomic before doing an console_unblank When doing an magic sysrq reboot on s390 the following bug message appears: SysRq : Resetting BUG: sleeping function called from invalid context at include/asm/semaphore.h:61 in_atomic():1, irqs_disabled():0 07000000004002a8 000000000fe6bc48 0000000000000002 0000000000000000 000000000fe6bce8 000000000fe6bc60 000000000fe6bc60 000000000012a79a 0000000000000000 07000000004002a8 0000000000000006 0000000000000000 0000000000000000 000000000fe6bc48 000000000000000d 000000000fe6bcb8 00000000004000c8 0000000000103234 000000000fe6bc48 000000000fe6bc90 Call Trace: (¬<00000000001031b2>| show_trace+0x12e/0x148) ¬<000000000011ffca>| __might_sleep+0x10a/0x118 ¬<0000000000129fba>| acquire_console_sem+0x92/0xf4 ¬<000000000012a2ca>| console_unblank+0xc2/0xc8 ¬<0000000000107bb4>| machine_restart+0x54/0x6c ¬<000000000028e806>| sysrq_handle_reboot+0x26/0x30 ¬<000000000028e52a>| __handle_sysrq+0xa6/0x180 ¬<0000000000140134>| run_workqueue+0xcc/0x18c ¬<000000000014029a>| worker_thread+0xa6/0x108 ¬<00000000001458e4>| kthread+0x64/0x9c ¬<0000000000106f0e>| kernel_thread_starter+0x6/0xc ¬<0000000000106f08>| kernel_thread_starter+0x0/0xc The only reason for doing a console_unblank on s390 is to flush the log buffer. We have to check for in_atomic before doing a console_unblank as the console is otherwise filled with an unrelated bug message. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-11-20 10:13:31 +00:00
if ((!in_interrupt() && !in_atomic()) || oops_in_progress)
/*
* Only unblank the console if we are called in enabled
* context or a bust_spinlocks cleared the way for us.
*/
console_unblank();
_machine_restart(command);
}
void machine_halt(void)
{
if (!in_interrupt() || oops_in_progress)
/*
* Only unblank the console if we are called in enabled
* context or a bust_spinlocks cleared the way for us.
*/
console_unblank();
_machine_halt();
}
void machine_power_off(void)
{
if (!in_interrupt() || oops_in_progress)
/*
* Only unblank the console if we are called in enabled
* context or a bust_spinlocks cleared the way for us.
*/
console_unblank();
_machine_power_off();
}
/*
* Dummy power off function.
*/
void (*pm_power_off)(void) = machine_power_off;
static int __init early_parse_mem(char *p)
{
memory_end = memparse(p, &p);
memory_end_set = 1;
return 0;
}
early_param("mem", early_parse_mem);
unsigned int user_mode = HOME_SPACE_MODE;
EXPORT_SYMBOL_GPL(user_mode);
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
static int set_amode_and_uaccess(unsigned long user_amode,
unsigned long user32_amode)
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
{
psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
#ifdef CONFIG_COMPAT
psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
PSW32_MASK_PSTATE;
#endif
psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
if (MACHINE_HAS_MVCOS) {
memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
return 1;
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
} else {
memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
return 0;
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
}
}
/*
* Switch kernel/user addressing modes?
*/
static int __init early_parse_switch_amode(char *p)
{
if (user_mode != SECONDARY_SPACE_MODE)
user_mode = PRIMARY_SPACE_MODE;
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
return 0;
}
early_param("switch_amode", early_parse_switch_amode);
static int __init early_parse_user_mode(char *p)
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
{
if (p && strcmp(p, "primary") == 0)
user_mode = PRIMARY_SPACE_MODE;
#ifdef CONFIG_S390_EXEC_PROTECT
else if (p && strcmp(p, "secondary") == 0)
user_mode = SECONDARY_SPACE_MODE;
#endif
else if (!p || strcmp(p, "home") == 0)
user_mode = HOME_SPACE_MODE;
else
return 1;
return 0;
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
}
early_param("user_mode", early_parse_user_mode);
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
#ifdef CONFIG_S390_EXEC_PROTECT
/*
* Enable execute protection?
*/
static int __init early_parse_noexec(char *p)
{
if (!strncmp(p, "off", 3))
return 0;
user_mode = SECONDARY_SPACE_MODE;
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
return 0;
}
early_param("noexec", early_parse_noexec);
#endif /* CONFIG_S390_EXEC_PROTECT */
static void setup_addressing_mode(void)
{
if (user_mode == SECONDARY_SPACE_MODE) {
if (set_amode_and_uaccess(PSW_ASC_SECONDARY,
PSW32_ASC_SECONDARY))
pr_info("Execute protection active, "
"mvcos available\n");
else
pr_info("Execute protection active, "
"mvcos not available\n");
} else if (user_mode == PRIMARY_SPACE_MODE) {
if (set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY))
pr_info("Address spaces switched, "
"mvcos available\n");
else
pr_info("Address spaces switched, "
"mvcos not available\n");
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
}
}
static void __init
setup_lowcore(void)
{
struct _lowcore *lc;
/*
* Setup lowcore for boot cpu
*/
BUILD_BUG_ON(sizeof(struct _lowcore) != LC_PAGES * 4096);
lc = __alloc_bootmem_low(LC_PAGES * PAGE_SIZE, LC_PAGES * PAGE_SIZE, 0);
lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
lc->restart_psw.addr =
PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
if (user_mode != HOME_SPACE_MODE)
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
lc->restart_psw.mask |= PSW_ASC_HOME;
lc->external_new_psw.mask = psw_kernel_bits;
lc->external_new_psw.addr =
PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
lc->program_new_psw.mask = psw_kernel_bits;
lc->program_new_psw.addr =
PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
lc->mcck_new_psw.mask =
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
lc->mcck_new_psw.addr =
PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
lc->io_new_psw.mask = psw_kernel_bits;
lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
lc->clock_comparator = -1ULL;
lc->kernel_stack = ((unsigned long) &init_thread_union) + THREAD_SIZE;
lc->async_stack = (unsigned long)
__alloc_bootmem(ASYNC_SIZE, ASYNC_SIZE, 0) + ASYNC_SIZE;
lc->panic_stack = (unsigned long)
__alloc_bootmem(PAGE_SIZE, PAGE_SIZE, 0) + PAGE_SIZE;
lc->current_task = (unsigned long) init_thread_union.thread_info.task;
lc->thread_info = (unsigned long) &init_thread_union;
lc->machine_flags = S390_lowcore.machine_flags;
#ifndef CONFIG_64BIT
if (MACHINE_HAS_IEEE) {
lc->extended_save_area_addr = (__u32)
__alloc_bootmem_low(PAGE_SIZE, PAGE_SIZE, 0);
/* enable extended save area */
__ctl_set_bit(14, 29);
}
#else
lc->cmf_hpp = -1ULL;
lc->vdso_per_cpu_data = (unsigned long) &lc->paste[0];
#endif
lc->sync_enter_timer = S390_lowcore.sync_enter_timer;
lc->async_enter_timer = S390_lowcore.async_enter_timer;
lc->exit_timer = S390_lowcore.exit_timer;
lc->user_timer = S390_lowcore.user_timer;
lc->system_timer = S390_lowcore.system_timer;
lc->steal_timer = S390_lowcore.steal_timer;
lc->last_update_timer = S390_lowcore.last_update_timer;
lc->last_update_clock = S390_lowcore.last_update_clock;
lc->ftrace_func = S390_lowcore.ftrace_func;
set_prefix((u32)(unsigned long) lc);
lowcore_ptr[0] = lc;
}
static void __init
setup_resources(void)
{
struct resource *res, *sub_res;
int i;
code_resource.start = (unsigned long) &_text;
code_resource.end = (unsigned long) &_etext - 1;
data_resource.start = (unsigned long) &_etext;
data_resource.end = (unsigned long) &_edata - 1;
for (i = 0; i < MEMORY_CHUNKS; i++) {
if (!memory_chunk[i].size)
continue;
res = alloc_bootmem_low(sizeof(struct resource));
res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
switch (memory_chunk[i].type) {
case CHUNK_READ_WRITE:
res->name = "System RAM";
break;
case CHUNK_READ_ONLY:
res->name = "System ROM";
res->flags |= IORESOURCE_READONLY;
break;
default:
res->name = "reserved";
}
res->start = memory_chunk[i].addr;
res->end = memory_chunk[i].addr + memory_chunk[i].size - 1;
request_resource(&iomem_resource, res);
if (code_resource.start >= res->start &&
code_resource.start <= res->end &&
code_resource.end > res->end) {
sub_res = alloc_bootmem_low(sizeof(struct resource));
memcpy(sub_res, &code_resource,
sizeof(struct resource));
sub_res->end = res->end;
code_resource.start = res->end + 1;
request_resource(res, sub_res);
}
if (code_resource.start >= res->start &&
code_resource.start <= res->end &&
code_resource.end <= res->end)
request_resource(res, &code_resource);
if (data_resource.start >= res->start &&
data_resource.start <= res->end &&
data_resource.end > res->end) {
sub_res = alloc_bootmem_low(sizeof(struct resource));
memcpy(sub_res, &data_resource,
sizeof(struct resource));
sub_res->end = res->end;
data_resource.start = res->end + 1;
request_resource(res, sub_res);
}
if (data_resource.start >= res->start &&
data_resource.start <= res->end &&
data_resource.end <= res->end)
request_resource(res, &data_resource);
}
}
unsigned long real_memory_size;
EXPORT_SYMBOL_GPL(real_memory_size);
static void __init setup_memory_end(void)
{
unsigned long memory_size;
unsigned long max_mem;
int i;
#ifdef CONFIG_ZFCPDUMP
if (ipl_info.type == IPL_TYPE_FCP_DUMP) {
memory_end = ZFCPDUMP_HSA_SIZE;
memory_end_set = 1;
}
#endif
memory_size = 0;
memory_end &= PAGE_MASK;
max_mem = memory_end ? min(VMEM_MAX_PHYS, memory_end) : VMEM_MAX_PHYS;
memory_end = min(max_mem, memory_end);
/*
* Make sure all chunks are MAX_ORDER aligned so we don't need the
* extra checks that HOLES_IN_ZONE would require.
*/
for (i = 0; i < MEMORY_CHUNKS; i++) {
unsigned long start, end;
struct mem_chunk *chunk;
unsigned long align;
chunk = &memory_chunk[i];
align = 1UL << (MAX_ORDER + PAGE_SHIFT - 1);
start = (chunk->addr + align - 1) & ~(align - 1);
end = (chunk->addr + chunk->size) & ~(align - 1);
if (start >= end)
memset(chunk, 0, sizeof(*chunk));
else {
chunk->addr = start;
chunk->size = end - start;
}
}
for (i = 0; i < MEMORY_CHUNKS; i++) {
struct mem_chunk *chunk = &memory_chunk[i];
real_memory_size = max(real_memory_size,
chunk->addr + chunk->size);
if (chunk->addr >= max_mem) {
memset(chunk, 0, sizeof(*chunk));
continue;
}
if (chunk->addr + chunk->size > max_mem)
chunk->size = max_mem - chunk->addr;
memory_size = max(memory_size, chunk->addr + chunk->size);
}
if (!memory_end)
memory_end = memory_size;
}
static void __init
setup_memory(void)
{
unsigned long bootmap_size;
unsigned long start_pfn, end_pfn;
int i;
/*
* partially used pages are not usable - thus
* we are rounding upwards:
*/
start_pfn = PFN_UP(__pa(&_end));
end_pfn = max_pfn = PFN_DOWN(memory_end);
#ifdef CONFIG_BLK_DEV_INITRD
/*
* Move the initrd in case the bitmap of the bootmem allocater
* would overwrite it.
*/
if (INITRD_START && INITRD_SIZE) {
unsigned long bmap_size;
unsigned long start;
bmap_size = bootmem_bootmap_pages(end_pfn - start_pfn + 1);
bmap_size = PFN_PHYS(bmap_size);
if (PFN_PHYS(start_pfn) + bmap_size > INITRD_START) {
start = PFN_PHYS(start_pfn) + bmap_size + PAGE_SIZE;
if (start + INITRD_SIZE > memory_end) {
pr_err("initrd extends beyond end of "
"memory (0x%08lx > 0x%08lx) "
"disabling initrd\n",
start + INITRD_SIZE, memory_end);
INITRD_START = INITRD_SIZE = 0;
} else {
pr_info("Moving initrd (0x%08lx -> "
"0x%08lx, size: %ld)\n",
INITRD_START, start, INITRD_SIZE);
memmove((void *) start, (void *) INITRD_START,
INITRD_SIZE);
INITRD_START = start;
}
}
}
#endif
/*
* Initialize the boot-time allocator
*/
bootmap_size = init_bootmem(start_pfn, end_pfn);
/*
* Register RAM areas with the bootmem allocator.
*/
for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
unsigned long start_chunk, end_chunk, pfn;
if (memory_chunk[i].type != CHUNK_READ_WRITE)
continue;
start_chunk = PFN_DOWN(memory_chunk[i].addr);
end_chunk = start_chunk + PFN_DOWN(memory_chunk[i].size);
end_chunk = min(end_chunk, end_pfn);
if (start_chunk >= end_chunk)
continue;
add_active_range(0, start_chunk, end_chunk);
pfn = max(start_chunk, start_pfn);
for (; pfn < end_chunk; pfn++)
page_set_storage_key(PFN_PHYS(pfn), PAGE_DEFAULT_KEY);
}
psw_set_key(PAGE_DEFAULT_KEY);
free_bootmem_with_active_regions(0, max_pfn);
/*
* Reserve memory used for lowcore/command line/kernel image.
*/
reserve_bootmem(0, (unsigned long)_ehead, BOOTMEM_DEFAULT);
reserve_bootmem((unsigned long)_stext,
PFN_PHYS(start_pfn) - (unsigned long)_stext,
BOOTMEM_DEFAULT);
/*
* Reserve the bootmem bitmap itself as well. We do this in two
* steps (first step was init_bootmem()) because this catches
* the (very unlikely) case of us accidentally initializing the
* bootmem allocator with an invalid RAM area.
*/
reserve_bootmem(start_pfn << PAGE_SHIFT, bootmap_size,
BOOTMEM_DEFAULT);
#ifdef CONFIG_BLK_DEV_INITRD
if (INITRD_START && INITRD_SIZE) {
if (INITRD_START + INITRD_SIZE <= memory_end) {
reserve_bootmem(INITRD_START, INITRD_SIZE,
BOOTMEM_DEFAULT);
initrd_start = INITRD_START;
initrd_end = initrd_start + INITRD_SIZE;
} else {
pr_err("initrd extends beyond end of "
"memory (0x%08lx > 0x%08lx) "
"disabling initrd\n",
initrd_start + INITRD_SIZE, memory_end);
initrd_start = initrd_end = 0;
}
}
#endif
}
/*
* Setup hardware capabilities.
*/
static void __init setup_hwcaps(void)
{
static const int stfl_bits[6] = { 0, 2, 7, 17, 19, 21 };
unsigned long long facility_list_extended;
unsigned int facility_list;
struct cpuid cpu_id;
int i;
facility_list = stfl();
/*
* The store facility list bits numbers as found in the principles
* of operation are numbered with bit 1UL<<31 as number 0 to
* bit 1UL<<0 as number 31.
* Bit 0: instructions named N3, "backported" to esa-mode
* Bit 2: z/Architecture mode is active
* Bit 7: the store-facility-list-extended facility is installed
* Bit 17: the message-security assist is installed
* Bit 19: the long-displacement facility is installed
* Bit 21: the extended-immediate facility is installed
* Bit 22: extended-translation facility 3 is installed
* Bit 30: extended-translation facility 3 enhancement facility
* These get translated to:
* HWCAP_S390_ESAN3 bit 0, HWCAP_S390_ZARCH bit 1,
* HWCAP_S390_STFLE bit 2, HWCAP_S390_MSA bit 3,
* HWCAP_S390_LDISP bit 4, HWCAP_S390_EIMM bit 5 and
* HWCAP_S390_ETF3EH bit 8 (22 && 30).
*/
for (i = 0; i < 6; i++)
if (facility_list & (1UL << (31 - stfl_bits[i])))
elf_hwcap |= 1UL << i;
if ((facility_list & (1UL << (31 - 22)))
&& (facility_list & (1UL << (31 - 30))))
elf_hwcap |= HWCAP_S390_ETF3EH;
/*
* Check for additional facilities with store-facility-list-extended.
* stfle stores doublewords (8 byte) with bit 1ULL<<63 as bit 0
* and 1ULL<<0 as bit 63. Bits 0-31 contain the same information
* as stored by stfl, bits 32-xxx contain additional facilities.
* How many facility words are stored depends on the number of
* doublewords passed to the instruction. The additional facilites
* are:
* Bit 42: decimal floating point facility is installed
* Bit 44: perform floating point operation facility is installed
* translated to:
* HWCAP_S390_DFP bit 6 (42 && 44).
*/
if ((elf_hwcap & (1UL << 2)) &&
__stfle(&facility_list_extended, 1) > 0) {
if ((facility_list_extended & (1ULL << (63 - 42)))
&& (facility_list_extended & (1ULL << (63 - 44))))
elf_hwcap |= HWCAP_S390_DFP;
}
/*
* Huge page support HWCAP_S390_HPAGE is bit 7.
*/
if (MACHINE_HAS_HPAGE)
elf_hwcap |= HWCAP_S390_HPAGE;
/*
* 64-bit register support for 31-bit processes
* HWCAP_S390_HIGH_GPRS is bit 9.
*/
elf_hwcap |= HWCAP_S390_HIGH_GPRS;
get_cpu_id(&cpu_id);
switch (cpu_id.machine) {
case 0x9672:
#if !defined(CONFIG_64BIT)
default: /* Use "g5" as default for 31 bit kernels. */
#endif
strcpy(elf_platform, "g5");
break;
case 0x2064:
case 0x2066:
#if defined(CONFIG_64BIT)
default: /* Use "z900" as default for 64 bit kernels. */
#endif
strcpy(elf_platform, "z900");
break;
case 0x2084:
case 0x2086:
strcpy(elf_platform, "z990");
break;
case 0x2094:
case 0x2096:
strcpy(elf_platform, "z9-109");
break;
case 0x2097:
case 0x2098:
strcpy(elf_platform, "z10");
break;
}
}
/*
* Setup function called from init/main.c just after the banner
* was printed.
*/
void __init
setup_arch(char **cmdline_p)
{
/*
* print what head.S has found out about the machine
*/
#ifndef CONFIG_64BIT
if (MACHINE_IS_VM)
pr_info("Linux is running as a z/VM "
"guest operating system in 31-bit mode\n");
else if (MACHINE_IS_LPAR)
pr_info("Linux is running natively in 31-bit mode\n");
if (MACHINE_HAS_IEEE)
pr_info("The hardware system has IEEE compatible "
"floating point units\n");
else
pr_info("The hardware system has no IEEE compatible "
"floating point units\n");
#else /* CONFIG_64BIT */
if (MACHINE_IS_VM)
pr_info("Linux is running as a z/VM "
"guest operating system in 64-bit mode\n");
else if (MACHINE_IS_KVM)
pr_info("Linux is running under KVM in 64-bit mode\n");
else if (MACHINE_IS_LPAR)
pr_info("Linux is running natively in 64-bit mode\n");
#endif /* CONFIG_64BIT */
/* Have one command line that is parsed and saved in /proc/cmdline */
/* boot_command_line has been already set up in early.c */
*cmdline_p = boot_command_line;
ROOT_DEV = Root_RAM0;
init_mm.start_code = PAGE_OFFSET;
init_mm.end_code = (unsigned long) &_etext;
init_mm.end_data = (unsigned long) &_edata;
init_mm.brk = (unsigned long) &_end;
if (MACHINE_HAS_MVCOS)
memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
else
memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
parse_early_param();
setup_ipl();
setup_memory_end();
[S390] noexec protection This provides a noexec protection on s390 hardware. Our hardware does not have any bits left in the pte for a hw noexec bit, so this is a different approach using shadow page tables and a special addressing mode that allows separate address spaces for code and data. As a special feature of our "secondary-space" addressing mode, separate page tables can be specified for the translation of data addresses (storage operands) and instruction addresses. The shadow page table is used for the instruction addresses and the standard page table for the data addresses. The shadow page table is linked to the standard page table by a pointer in page->lru.next of the struct page corresponding to the page that contains the standard page table (since page->private is not really private with the pte_lock and the page table pages are not in the LRU list). Depending on the software bits of a pte, it is either inserted into both page tables or just into the standard (data) page table. Pages of a vma that does not have the VM_EXEC bit set get mapped only in the data address space. Any try to execute code on such a page will cause a page translation exception. The standard reaction to this is a SIGSEGV with two exceptions: the two system call opcodes 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) are allowed. They are stored by the kernel to the signal stack frame. Unfortunately, the signal return mechanism cannot be modified to use an SA_RESTORER because the exception unwinding code depends on the system call opcode stored behind the signal stack frame. This feature requires that user space is executed in secondary-space mode and the kernel in home-space mode, which means that the addressing modes need to be switched and that the noexec protection only works for user space. After switching the addressing modes, we cannot use the mvcp/mvcs instructions anymore to copy between kernel and user space. A new mvcos instruction has been added to the z9 EC/BC hardware which allows to copy between arbitrary address spaces, but on older hardware the page tables need to be walked manually. Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-02-05 20:18:17 +00:00
setup_addressing_mode();
setup_memory();
setup_resources();
setup_lowcore();
cpu_init();
s390_init_cpu_topology();
/*
* Setup capabilities (ELF_HWCAP & ELF_PLATFORM).
*/
setup_hwcaps();
/*
* Create kernel page tables and switch to virtual addressing.
*/
paging_init();
/* Setup default console */
conmode_default();
set_preferred_console();
/* Setup zfcpdump support */
setup_zfcpdump(console_devno);
}