9 files changed, 111 insertions, 48 deletions

diff --git a/arch/s390/kernel/compat_linux.c b/arch/s390/kernel/compat_linux.c
index cf84d697daed..666bb6daa148 100644
--- a/arch/s390/kernel/compat_linux.c
+++ b/arch/s390/kernel/compat_linux.c
@@ -69,6 +69,12 @@
 
 #include "compat_linux.h"
 
+long psw_user32_bits    = (PSW_BASE32_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
+                           PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
+                           PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
+long psw32_user_bits    = (PSW32_BASE_BITS | PSW32_MASK_DAT | PSW32_ASC_HOME |
+                           PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
+                           PSW32_MASK_PSTATE);
  
 /* For this source file, we want overflow handling. */
 
diff --git a/arch/s390/kernel/compat_linux.h b/arch/s390/kernel/compat_linux.h
index 1a18e29668ef..e89f8c0c42a0 100644
--- a/arch/s390/kernel/compat_linux.h
+++ b/arch/s390/kernel/compat_linux.h
@@ -115,37 +115,6 @@ typedef struct
         __u32   addr;
 } _psw_t32 __attribute__ ((aligned(8)));
 
-#define PSW32_MASK_PER          0x40000000UL
-#define PSW32_MASK_DAT          0x04000000UL
-#define PSW32_MASK_IO           0x02000000UL
-#define PSW32_MASK_EXT          0x01000000UL
-#define PSW32_MASK_KEY          0x00F00000UL
-#define PSW32_MASK_MCHECK       0x00040000UL
-#define PSW32_MASK_WAIT         0x00020000UL
-#define PSW32_MASK_PSTATE       0x00010000UL
-#define PSW32_MASK_ASC          0x0000C000UL
-#define PSW32_MASK_CC           0x00003000UL
-#define PSW32_MASK_PM           0x00000f00UL
-
-#define PSW32_ADDR_AMODE31      0x80000000UL
-#define PSW32_ADDR_INSN         0x7FFFFFFFUL
-
-#define PSW32_BASE_BITS         0x00080000UL
-
-#define PSW32_ASC_PRIMARY       0x00000000UL
-#define PSW32_ASC_ACCREG        0x00004000UL
-#define PSW32_ASC_SECONDARY     0x00008000UL
-#define PSW32_ASC_HOME          0x0000C000UL
-
-#define PSW32_USER_BITS (PSW32_BASE_BITS | PSW32_MASK_DAT | PSW32_ASC_HOME | \
-                         PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK | \
-                         PSW32_MASK_PSTATE)
-
-#define PSW32_MASK_MERGE(CURRENT,NEW) \
-        (((CURRENT) & ~(PSW32_MASK_CC|PSW32_MASK_PM)) | \
-         ((NEW) & (PSW32_MASK_CC|PSW32_MASK_PM)))
-
-
 typedef struct
 {
         _psw_t32        psw;
diff --git a/arch/s390/kernel/compat_signal.c b/arch/s390/kernel/compat_signal.c
index 8d17b2ab6f21..887a9881d0d0 100644
--- a/arch/s390/kernel/compat_signal.c
+++ b/arch/s390/kernel/compat_signal.c
@@ -298,7 +298,7 @@ static int save_sigregs32(struct pt_regs *regs, _sigregs32 __user *sregs)
         _s390_regs_common32 regs32;
         int err, i;
 
-        regs32.psw.mask = PSW32_MASK_MERGE(PSW32_USER_BITS,
+        regs32.psw.mask = PSW32_MASK_MERGE(psw32_user_bits,
                                            (__u32)(regs->psw.mask >> 32));
         regs32.psw.addr = PSW32_ADDR_AMODE31 | (__u32) regs->psw.addr;
         for (i = 0; i < NUM_GPRS; i++)
diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c
index 9e9972e8a52b..2c91226e1d40 100644
--- a/arch/s390/kernel/ipl.c
+++ b/arch/s390/kernel/ipl.c
@@ -1016,12 +1016,12 @@ void s390_reset_system(void)
         __ctl_clear_bit(0,28);
 
         /* Set new machine check handler */
-        S390_lowcore.mcck_new_psw.mask = PSW_KERNEL_BITS & ~PSW_MASK_MCHECK;
+        S390_lowcore.mcck_new_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
         S390_lowcore.mcck_new_psw.addr =
                 PSW_ADDR_AMODE | (unsigned long) &reset_mcck_handler;
 
         /* Set new program check handler */
-        S390_lowcore.program_new_psw.mask = PSW_KERNEL_BITS & ~PSW_MASK_MCHECK;
+        S390_lowcore.program_new_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
         S390_lowcore.program_new_psw.addr =
                 PSW_ADDR_AMODE | (unsigned long) &reset_pgm_handler;
 
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 6603fbb41d07..5acfac654f9d 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -144,7 +144,7 @@ static void default_idle(void)
 
         trace_hardirqs_on();
         /* Wait for external, I/O or machine check interrupt. */
-        __load_psw_mask(PSW_KERNEL_BITS | PSW_MASK_WAIT |
+        __load_psw_mask(psw_kernel_bits | PSW_MASK_WAIT |
                         PSW_MASK_IO | PSW_MASK_EXT);
 }
 
@@ -190,7 +190,7 @@ int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
         struct pt_regs regs;
 
         memset(&regs, 0, sizeof(regs));
-        regs.psw.mask = PSW_KERNEL_BITS | PSW_MASK_IO | PSW_MASK_EXT;
+        regs.psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
         regs.psw.addr = (unsigned long) kernel_thread_starter | PSW_ADDR_AMODE;
         regs.gprs[9] = (unsigned long) fn;
         regs.gprs[10] = (unsigned long) arg;
diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index 29fde70090fe..2a8f0872ea8b 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -230,9 +230,9 @@ poke_user(struct task_struct *child, addr_t addr, addr_t data)
                  */
                 if (addr == (addr_t) &dummy->regs.psw.mask &&
 #ifdef CONFIG_COMPAT
-                    data != PSW_MASK_MERGE(PSW_USER32_BITS, data) &&
+                    data != PSW_MASK_MERGE(psw_user32_bits, data) &&
 #endif
-                    data != PSW_MASK_MERGE(PSW_USER_BITS, data))
+                    data != PSW_MASK_MERGE(psw_user_bits, data))
                         /* Invalid psw mask. */
                         return -EINVAL;
 #ifndef CONFIG_64BIT
@@ -393,7 +393,7 @@ peek_user_emu31(struct task_struct *child, addr_t addr, addr_t data)
                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
                         /* Fake a 31 bit psw mask. */
                         tmp = (__u32)(task_pt_regs(child)->psw.mask >> 32);
-                        tmp = PSW32_MASK_MERGE(PSW32_USER_BITS, tmp);
+                        tmp = PSW32_MASK_MERGE(psw32_user_bits, tmp);
                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
                         /* Fake a 31 bit psw address. */
                         tmp = (__u32) task_pt_regs(child)->psw.addr |
@@ -468,11 +468,11 @@ poke_user_emu31(struct task_struct *child, addr_t addr, addr_t data)
                  */
                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
                         /* Build a 64 bit psw mask from 31 bit mask. */
-                        if (tmp != PSW32_MASK_MERGE(PSW32_USER_BITS, tmp))
+                        if (tmp != PSW32_MASK_MERGE(psw32_user_bits, tmp))
                                 /* Invalid psw mask. */
                                 return -EINVAL;
                         task_pt_regs(child)->psw.mask =
-                                PSW_MASK_MERGE(PSW_USER32_BITS, (__u64) tmp << 32);
+                                PSW_MASK_MERGE(psw_user32_bits, (__u64) tmp << 32);
                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
                         /* Build a 64 bit psw address from 31 bit address. */
                         task_pt_regs(child)->psw.addr =
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 25bf7277d311..b1b9a931237d 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -50,6 +50,13 @@
 #include <asm/page.h>
 #include <asm/ptrace.h>
 #include <asm/sections.h>
+#include <asm/compat.h>
+
+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.
@@ -383,6 +390,84 @@ static int __init early_parse_ipldelay(char *p)
 }
 early_param("ipldelay", early_parse_ipldelay);
 
+#ifdef CONFIG_S390_SWITCH_AMODE
+unsigned int switch_amode = 0;
+EXPORT_SYMBOL_GPL(switch_amode);
+
+static inline void set_amode_and_uaccess(unsigned long user_amode,
+                                         unsigned long user32_amode)
+{
+        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) {
+                printk("mvcos available.\n");
+                memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
+        } else {
+                printk("mvcos not available.\n");
+                memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
+        }
+}
+
+/*
+ * Switch kernel/user addressing modes?
+ */
+static int __init early_parse_switch_amode(char *p)
+{
+        switch_amode = 1;
+        return 0;
+}
+early_param("switch_amode", early_parse_switch_amode);
+
+#else /* CONFIG_S390_SWITCH_AMODE */
+static inline void set_amode_and_uaccess(unsigned long user_amode,
+                                         unsigned long user32_amode)
+{
+}
+#endif /* CONFIG_S390_SWITCH_AMODE */
+
+#ifdef CONFIG_S390_EXEC_PROTECT
+unsigned int s390_noexec = 0;
+EXPORT_SYMBOL_GPL(s390_noexec);
+
+/*
+ * Enable execute protection?
+ */
+static int __init early_parse_noexec(char *p)
+{
+        if (!strncmp(p, "off", 3))
+                return 0;
+        switch_amode = 1;
+        s390_noexec = 1;
+        return 0;
+}
+early_param("noexec", early_parse_noexec);
+#endif /* CONFIG_S390_EXEC_PROTECT */
+
+static void setup_addressing_mode(void)
+{
+        if (s390_noexec) {
+                printk("S390 execute protection active, ");
+                set_amode_and_uaccess(PSW_ASC_SECONDARY, PSW32_ASC_SECONDARY);
+                return;
+        }
+        if (switch_amode) {
+                printk("S390 address spaces switched, ");
+                set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY);
+        }
+}
+
 static void __init
 setup_lowcore(void)
 {
@@ -399,19 +484,21 @@ setup_lowcore(void)
         lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
         lc->restart_psw.addr =
                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
-        lc->external_new_psw.mask = PSW_KERNEL_BITS;
+        if (switch_amode)
+                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;
-        lc->svc_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_IO | PSW_MASK_EXT;
+        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;
-        lc->program_new_psw.mask = PSW_KERNEL_BITS;
+        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 =
-                PSW_KERNEL_BITS & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
+                psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
         lc->mcck_new_psw.addr =
                 PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
-        lc->io_new_psw.mask = PSW_KERNEL_BITS;
+        lc->io_new_psw.mask = psw_kernel_bits;
         lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
         lc->ipl_device = S390_lowcore.ipl_device;
         lc->jiffy_timer = -1LL;
@@ -645,6 +732,7 @@ setup_arch(char **cmdline_p)
         parse_early_param();
 
         setup_memory_end();
+        setup_addressing_mode();
         setup_memory();
         setup_resources();
         setup_lowcore();
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index 4c8a7954ef48..554f9cf7499c 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -119,7 +119,7 @@ static int save_sigregs(struct pt_regs *regs, _sigregs __user *sregs)
 
         /* Copy a 'clean' PSW mask to the user to avoid leaking
            information about whether PER is currently on.  */
-        user_sregs.regs.psw.mask = PSW_MASK_MERGE(PSW_USER_BITS, regs->psw.mask);
+        user_sregs.regs.psw.mask = PSW_MASK_MERGE(psw_user_bits, regs->psw.mask);
         user_sregs.regs.psw.addr = regs->psw.addr;
         memcpy(&user_sregs.regs.gprs, &regs->gprs, sizeof(sregs->regs.gprs));
         memcpy(&user_sregs.regs.acrs, current->thread.acrs,
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 3cb7e1032072..cb155d9fd749 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -244,7 +244,7 @@ static inline void do_wait_for_stop(void)
 void smp_send_stop(void)
 {
         /* Disable all interrupts/machine checks */
-        __load_psw_mask(PSW_KERNEL_BITS & ~PSW_MASK_MCHECK);
+        __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK);
 
         /* write magic number to zero page (absolute 0) */
         lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC;