5 files changed, 53 insertions, 21 deletions

diff --git a/arch/ia64/kernel/cyclone.c b/arch/ia64/kernel/cyclone.c
index 6ade3790ce07..e00b21514f7c 100644
--- a/arch/ia64/kernel/cyclone.c
+++ b/arch/ia64/kernel/cyclone.c
@@ -36,7 +36,7 @@ int __init init_cyclone_clock(void)
         u32* volatile cyclone_timer;    /* Cyclone MPMC0 register */
 
         if (!use_cyclone)
-                return -ENODEV;
+                return 0;
 
         printk(KERN_INFO "Summit chipset: Starting Cyclone Counter.\n");
 
diff --git a/arch/ia64/kernel/fsys.S b/arch/ia64/kernel/fsys.S
index ac6055c83115..7a05b1cb2ad5 100644
--- a/arch/ia64/kernel/fsys.S
+++ b/arch/ia64/kernel/fsys.S
@@ -878,8 +878,7 @@ fsyscall_table:
         data8 0                         // timer_delete
         data8 0                         // clock_settime
         data8 fsys_clock_gettime        // clock_gettime
-        #define __NR_syscall_last       1255
 
-        .space 8*(NR_syscalls + 1024 - __NR_syscall_last), 0
-
-        .org fsyscall_table + 8*NR_syscalls     // guard against failures to increase NR_syscalls
+        // fill in zeros for the remaining entries
+        .zero:
+        .space fsyscall_table + 8*NR_syscalls - .zero, 0
diff --git a/arch/ia64/kernel/ivt.S b/arch/ia64/kernel/ivt.S
index 301f2e9d262e..dcd906fe5749 100644
--- a/arch/ia64/kernel/ivt.S
+++ b/arch/ia64/kernel/ivt.S
@@ -561,11 +561,12 @@ ENTRY(dirty_bit)
         ;;                                      // avoid RAW on r18
         mov ar.ccv=r18                          // set compare value for cmpxchg
         or r25=_PAGE_D|_PAGE_A,r18              // set the dirty and accessed bits
+        tbit.z p7,p6 = r18,_PAGE_P_BIT          // Check present bit
         ;;
-        cmpxchg8.acq r26=[r17],r25,ar.ccv
+(p6)    cmpxchg8.acq r26=[r17],r25,ar.ccv       // Only update if page is present
         mov r24=PAGE_SHIFT<<2
         ;;
-        cmp.eq p6,p7=r26,r18
+(p6)    cmp.eq p6,p7=r26,r18                    // Only compare if page is present
         ;;
 (p6)    itc.d r25                               // install updated PTE
         ;;
@@ -626,11 +627,12 @@ ENTRY(iaccess_bit)
         ;;
         mov ar.ccv=r18                          // set compare value for cmpxchg
         or r25=_PAGE_A,r18                      // set the accessed bit
+        tbit.z p7,p6 = r18,_PAGE_P_BIT          // Check present bit
         ;;
-        cmpxchg8.acq r26=[r17],r25,ar.ccv
+(p6)    cmpxchg8.acq r26=[r17],r25,ar.ccv       // Only if page present
         mov r24=PAGE_SHIFT<<2
         ;;
-        cmp.eq p6,p7=r26,r18
+(p6)    cmp.eq p6,p7=r26,r18                    // Only if page present
         ;;
 (p6)    itc.i r25                               // install updated PTE
         ;;
@@ -680,11 +682,12 @@ ENTRY(daccess_bit)
         ;;                                      // avoid RAW on r18
         mov ar.ccv=r18                          // set compare value for cmpxchg
         or r25=_PAGE_A,r18                      // set the dirty bit
+        tbit.z p7,p6 = r18,_PAGE_P_BIT          // Check present bit
         ;;
-        cmpxchg8.acq r26=[r17],r25,ar.ccv
+(p6)    cmpxchg8.acq r26=[r17],r25,ar.ccv       // Only if page is present
         mov r24=PAGE_SHIFT<<2
         ;;
-        cmp.eq p6,p7=r26,r18
+(p6)    cmp.eq p6,p7=r26,r18                    // Only if page is present
         ;;
 (p6)    itc.d r25                               // install updated PTE
         /*
@@ -1362,7 +1365,6 @@ END(debug_vector)
 // 0x5a00 Entry 30 (size 16 bundles) Unaligned Reference (57)
 ENTRY(unaligned_access)
         DBG_FAULT(30)
-        mov r16=cr.ipsr
         mov r31=pr              // prepare to save predicates
         ;;
         br.sptk.many dispatch_unaligned_handler
diff --git a/arch/ia64/kernel/mca_drv.c b/arch/ia64/kernel/mca_drv.c
index 8fd93afa75a7..e883d85906db 100644
--- a/arch/ia64/kernel/mca_drv.c
+++ b/arch/ia64/kernel/mca_drv.c
@@ -123,8 +123,9 @@ mca_page_isolate(unsigned long paddr)
 void
 mca_handler_bh(unsigned long paddr)
 {
-        printk(KERN_DEBUG "OS_MCA: process [pid: %d](%s) encounters MCA.\n",
-                current->pid, current->comm);
+        printk(KERN_ERR
+                "OS_MCA: process [pid: %d](%s) encounters MCA (paddr=%lx)\n",
+                current->pid, current->comm, paddr);
 
         spin_lock(&mca_bh_lock);
         switch (mca_page_isolate(paddr)) {
@@ -132,7 +133,7 @@ mca_handler_bh(unsigned long paddr)
                 printk(KERN_DEBUG "Page isolation: ( %lx ) success.\n", paddr);
                 break;
         case ISOLATE_NG:
-                printk(KERN_DEBUG "Page isolation: ( %lx ) failure.\n", paddr);
+                printk(KERN_CRIT "Page isolation: ( %lx ) failure.\n", paddr);
                 break;
         default:
                 break;
@@ -567,10 +568,15 @@ recover_from_processor_error(int platform, slidx_table_t *slidx,
                 return 0;
 
         /*
-         * If there is no bus error, record is weird but we need not to recover.
+         * The cache check and bus check bits have four possible states
+         *   cc bc
+         *    0  0      Weird record, not recovered
+         *    1  0      Cache error, not recovered
+         *    0  1      I/O error, attempt recovery
+         *    1  1      Memory error, attempt recovery
          */
         if (psp->bc == 0 || pbci == NULL)
-                return 1;
+                return 0;
 
         /*
          * Sorry, we cannot handle so many.
diff --git a/arch/ia64/kernel/unaligned.c b/arch/ia64/kernel/unaligned.c
index f9e0ae936d1a..1e357550c776 100644
--- a/arch/ia64/kernel/unaligned.c
+++ b/arch/ia64/kernel/unaligned.c
@@ -24,7 +24,7 @@
 #include <asm/uaccess.h>
 #include <asm/unaligned.h>
 
-extern void die_if_kernel(char *str, struct pt_regs *regs, long err) __attribute__ ((noreturn));
+extern void die_if_kernel(char *str, struct pt_regs *regs, long err);
 
 #undef DEBUG_UNALIGNED_TRAP
 
@@ -53,6 +53,15 @@ dump (const char *str, void *vp, size_t len)
 #define SIGN_EXT9               0xffffffffffffff00ul
 
 /*
+ *  sysctl settable hook which tells the kernel whether to honor the
+ *  IA64_THREAD_UAC_NOPRINT prctl.  Because this is user settable, we want
+ *  to allow the super user to enable/disable this for security reasons
+ *  (i.e. don't allow attacker to fill up logs with unaligned accesses).
+ */
+int no_unaligned_warning;
+static int noprint_warning;
+
+/*
  * For M-unit:
  *
  *  opcode |   m  |   x6    |
@@ -1324,8 +1333,9 @@ ia64_handle_unaligned (unsigned long ifa, struct pt_regs *regs)
                 if ((current->thread.flags & IA64_THREAD_UAC_SIGBUS) != 0)
                         goto force_sigbus;
 
-                if (!(current->thread.flags & IA64_THREAD_UAC_NOPRINT)
-                    && within_logging_rate_limit())
+                if (!no_unaligned_warning &&
+                    !(current->thread.flags & IA64_THREAD_UAC_NOPRINT) &&
+                    within_logging_rate_limit())
                 {
                         char buf[200];  /* comm[] is at most 16 bytes... */
                         size_t len;
@@ -1340,7 +1350,22 @@ ia64_handle_unaligned (unsigned long ifa, struct pt_regs *regs)
                         if (user_mode(regs))
                                 tty_write_message(current->signal->tty, buf);
                         buf[len-1] = '\0';      /* drop '\r' */
-                        printk(KERN_WARNING "%s", buf); /* watch for command names containing %s */
+                        /* watch for command names containing %s */
+                        printk(KERN_WARNING "%s", buf);
+                } else {
+                        if (no_unaligned_warning && !noprint_warning) {
+                                noprint_warning = 1;
+                                printk(KERN_WARNING "%s(%d) encountered an "
+                                       "unaligned exception which required\n"
+                                       "kernel assistance, which degrades "
+                                       "the performance of the application.\n"
+                                       "Unaligned exception warnings have "
+                                       "been disabled by the system "
+                                       "administrator\n"
+                                       "echo 0 > /proc/sys/kernel/ignore-"
+                                       "unaligned-usertrap to re-enable\n",
+                                       current->comm, current->pid);
+                        }
                 }
         } else {
                 if (within_logging_rate_limit())