7 files changed, 96 insertions, 27 deletions

diff --git a/arch/ia64/kernel/acpi.c b/arch/ia64/kernel/acpi.c
index 19709a079635..853d1f11be00 100644
--- a/arch/ia64/kernel/acpi.c
+++ b/arch/ia64/kernel/acpi.c
@@ -117,7 +117,10 @@ acpi_get_sysname(void)
         if (!strcmp(hdr->oem_id, "HP")) {
                 return "hpzx1";
         } else if (!strcmp(hdr->oem_id, "SGI")) {
-                return "sn2";
+                if (!strcmp(hdr->oem_table_id + 4, "UV"))
+                        return "uv";
+                else
+                        return "sn2";
         }
 
         return "dig";
@@ -130,6 +133,8 @@ acpi_get_sysname(void)
         return "hpzx1_swiotlb";
 # elif defined (CONFIG_IA64_SGI_SN2)
         return "sn2";
+# elif defined (CONFIG_IA64_SGI_UV)
+        return "uv";
 # elif defined (CONFIG_IA64_DIG)
         return "dig";
 # else
@@ -622,6 +627,9 @@ void acpi_unregister_gsi(u32 gsi)
         if (acpi_irq_model == ACPI_IRQ_MODEL_PLATFORM)
                 return;
 
+        if (has_8259 && gsi < 16)
+                return;
+
         iosapic_unregister_intr(gsi);
 }
 
diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S
index e49ad8c5dc69..ca2bb95726de 100644
--- a/arch/ia64/kernel/entry.S
+++ b/arch/ia64/kernel/entry.S
@@ -1156,6 +1156,9 @@ skip_rbs_switch:
          *      r31 = current->thread_info->flags
          * On exit:
          *      p6 = TRUE if work-pending-check needs to be redone
+         *
+         * Interrupts are disabled on entry, reenabled depend on work, and
+         * disabled on exit.
          */
 .work_pending_syscall:
         add r2=-8,r2
@@ -1164,16 +1167,16 @@ skip_rbs_switch:
         st8 [r2]=r8
         st8 [r3]=r10
 .work_pending:
-        tbit.z p6,p0=r31,TIF_NEED_RESCHED               // current_thread_info()->need_resched==0?
+        tbit.z p6,p0=r31,TIF_NEED_RESCHED       // is resched not needed?
 (p6)    br.cond.sptk.few .notify
 #ifdef CONFIG_PREEMPT
 (pKStk) dep r21=-1,r0,PREEMPT_ACTIVE_BIT,1
         ;;
 (pKStk) st4 [r20]=r21
-        ssm psr.i               // enable interrupts
 #endif
+        ssm psr.i               // enable interrupts
         br.call.spnt.many rp=schedule
-.ret9:  cmp.eq p6,p0=r0,r0                              // p6 <- 1
+.ret9:  cmp.eq p6,p0=r0,r0      // p6 <- 1 (re-check)
         rsm psr.i               // disable interrupts
         ;;
 #ifdef CONFIG_PREEMPT
@@ -1182,13 +1185,13 @@ skip_rbs_switch:
 (pKStk) st4 [r20]=r0            // preempt_count() <- 0
 #endif
 (pLvSys)br.cond.sptk.few  .work_pending_syscall_end
-        br.cond.sptk.many .work_processed_kernel        // re-check
+        br.cond.sptk.many .work_processed_kernel
 
 .notify:
 (pUStk) br.call.spnt.many rp=notify_resume_user
-.ret10: cmp.ne p6,p0=r0,r0                              // p6 <- 0
+.ret10: cmp.ne p6,p0=r0,r0      // p6 <- 0 (don't re-check)
 (pLvSys)br.cond.sptk.few  .work_pending_syscall_end
-        br.cond.sptk.many .work_processed_kernel        // don't re-check
+        br.cond.sptk.many .work_processed_kernel
 
 .work_pending_syscall_end:
         adds r2=PT(R8)+16,r12
@@ -1196,7 +1199,7 @@ skip_rbs_switch:
         ;;
         ld8 r8=[r2]
         ld8 r10=[r3]
-        br.cond.sptk.many .work_processed_syscall       // re-check
+        br.cond.sptk.many .work_processed_syscall
 
 END(ia64_leave_kernel)
 
@@ -1234,9 +1237,12 @@ GLOBAL_ENTRY(ia64_invoke_schedule_tail)
 END(ia64_invoke_schedule_tail)
 
         /*
-         * Setup stack and call do_notify_resume_user().  Note that pSys and pNonSys need to
-         * be set up by the caller.  We declare 8 input registers so the system call
-         * args get preserved, in case we need to restart a system call.
+         * Setup stack and call do_notify_resume_user(), keeping interrupts
+         * disabled.
+         *
+         * Note that pSys and pNonSys need to be set up by the caller.
+         * We declare 8 input registers so the system call args get preserved,
+         * in case we need to restart a system call.
          */
 ENTRY(notify_resume_user)
         .prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
diff --git a/arch/ia64/kernel/palinfo.c b/arch/ia64/kernel/palinfo.c
index 4547a2092af9..9dc00f7fe10e 100644
--- a/arch/ia64/kernel/palinfo.c
+++ b/arch/ia64/kernel/palinfo.c
@@ -900,12 +900,6 @@ static void
 palinfo_smp_call(void *info)
 {
         palinfo_smp_data_t *data = (palinfo_smp_data_t *)info;
-        if (data == NULL) {
-                printk(KERN_ERR "palinfo: data pointer is NULL\n");
-                data->ret = 0; /* no output */
-                return;
-        }
-        /* does this actual call */
         data->ret = (*data->func)(data->page);
 }
 
diff --git a/arch/ia64/kernel/perfmon.c b/arch/ia64/kernel/perfmon.c
index c1ad27de2dd2..71d05133f556 100644
--- a/arch/ia64/kernel/perfmon.c
+++ b/arch/ia64/kernel/perfmon.c
@@ -5013,12 +5013,13 @@ pfm_context_force_terminate(pfm_context_t *ctx, struct pt_regs *regs)
 }
 
 static int pfm_ovfl_notify_user(pfm_context_t *ctx, unsigned long ovfl_pmds);
+
  /*
   * pfm_handle_work() can be called with interrupts enabled
   * (TIF_NEED_RESCHED) or disabled. The down_interruptible
   * call may sleep, therefore we must re-enable interrupts
   * to avoid deadlocks. It is safe to do so because this function
-  * is called ONLY when returning to user level (PUStk=1), in which case
+  * is called ONLY when returning to user level (pUStk=1), in which case
   * there is no risk of kernel stack overflow due to deep
   * interrupt nesting.
   */
@@ -5034,7 +5035,8 @@ pfm_handle_work(void)
 
         ctx = PFM_GET_CTX(current);
         if (ctx == NULL) {
-                printk(KERN_ERR "perfmon: [%d] has no PFM context\n", task_pid_nr(current));
+                printk(KERN_ERR "perfmon: [%d] has no PFM context\n",
+                        task_pid_nr(current));
                 return;
         }
 
@@ -5058,11 +5060,12 @@ pfm_handle_work(void)
         /*
          * must be done before we check for simple-reset mode
          */
-        if (ctx->ctx_fl_going_zombie || ctx->ctx_state == PFM_CTX_ZOMBIE) goto do_zombie;
-
+        if (ctx->ctx_fl_going_zombie || ctx->ctx_state == PFM_CTX_ZOMBIE)
+                goto do_zombie;
 
         //if (CTX_OVFL_NOBLOCK(ctx)) goto skip_blocking;
-        if (reason == PFM_TRAP_REASON_RESET) goto skip_blocking;
+        if (reason == PFM_TRAP_REASON_RESET)
+                goto skip_blocking;
 
         /*
          * restore interrupt mask to what it was on entry.
@@ -5110,7 +5113,8 @@ do_zombie:
         /*
          * in case of interruption of down() we don't restart anything
          */
-        if (ret < 0) goto nothing_to_do;
+        if (ret < 0)
+                goto nothing_to_do;
 
 skip_blocking:
         pfm_resume_after_ovfl(ctx, ovfl_regs, regs);
diff --git a/arch/ia64/kernel/process.c b/arch/ia64/kernel/process.c
index 58dcfac5ea88..a3a34b4eb038 100644
--- a/arch/ia64/kernel/process.c
+++ b/arch/ia64/kernel/process.c
@@ -167,11 +167,18 @@ void tsk_clear_notify_resume(struct task_struct *tsk)
         clear_ti_thread_flag(task_thread_info(tsk), TIF_NOTIFY_RESUME);
 }
 
+/*
+ * do_notify_resume_user():
+ *      Called from notify_resume_user at entry.S, with interrupts disabled.
+ */
 void
-do_notify_resume_user (sigset_t *unused, struct sigscratch *scr, long in_syscall)
+do_notify_resume_user(sigset_t *unused, struct sigscratch *scr, long in_syscall)
 {
         if (fsys_mode(current, &scr->pt)) {
-                /* defer signal-handling etc. until we return to privilege-level 0.  */
+                /*
+                 * defer signal-handling etc. until we return to
+                 * privilege-level 0.
+                 */
                 if (!ia64_psr(&scr->pt)->lp)
                         ia64_psr(&scr->pt)->lp = 1;
                 return;
@@ -179,16 +186,26 @@ do_notify_resume_user (sigset_t *unused, struct sigscratch *scr, long in_syscall
 
 #ifdef CONFIG_PERFMON
         if (current->thread.pfm_needs_checking)
+                /*
+                 * Note: pfm_handle_work() allow us to call it with interrupts
+                 * disabled, and may enable interrupts within the function.
+                 */
                 pfm_handle_work();
 #endif
 
         /* deal with pending signal delivery */
-        if (test_thread_flag(TIF_SIGPENDING))
+        if (test_thread_flag(TIF_SIGPENDING)) {
+                local_irq_enable();     /* force interrupt enable */
                 ia64_do_signal(scr, in_syscall);
+        }
 
         /* copy user rbs to kernel rbs */
-        if (unlikely(test_thread_flag(TIF_RESTORE_RSE)))
+        if (unlikely(test_thread_flag(TIF_RESTORE_RSE))) {
+                local_irq_enable();     /* force interrupt enable */
                 ia64_sync_krbs();
+        }
+
+        local_irq_disable();    /* force interrupt disable */
 }
 
 static int pal_halt        = 1;
diff --git a/arch/ia64/kernel/sal.c b/arch/ia64/kernel/sal.c
index a3022dc48ef8..7e0259709c04 100644
--- a/arch/ia64/kernel/sal.c
+++ b/arch/ia64/kernel/sal.c
@@ -229,6 +229,14 @@ static void __init sal_desc_ap_wakeup(void *p) { }
  */
 static int sal_cache_flush_drops_interrupts;
 
+static int __init
+force_pal_cache_flush(char *str)
+{
+        sal_cache_flush_drops_interrupts = 1;
+        return 0;
+}
+early_param("force_pal_cache_flush", force_pal_cache_flush);
+
 void __init
 check_sal_cache_flush (void)
 {
@@ -237,6 +245,9 @@ check_sal_cache_flush (void)
         u64 vector, cache_type = 3;
         struct ia64_sal_retval isrv;
 
+        if (sal_cache_flush_drops_interrupts)
+                return;
+
         cpu = get_cpu();
         local_irq_save(flags);
 
diff --git a/arch/ia64/kernel/setup.c b/arch/ia64/kernel/setup.c
index 5015ca1275ca..e9596cd0cdab 100644
--- a/arch/ia64/kernel/setup.c
+++ b/arch/ia64/kernel/setup.c
@@ -239,6 +239,25 @@ __initcall(register_memory);
 
 
 #ifdef CONFIG_KEXEC
+
+/*
+ * This function checks if the reserved crashkernel is allowed on the specific
+ * IA64 machine flavour. Machines without an IO TLB use swiotlb and require
+ * some memory below 4 GB (i.e. in 32 bit area), see the implementation of
+ * lib/swiotlb.c. The hpzx1 architecture has an IO TLB but cannot use that
+ * in kdump case. See the comment in sba_init() in sba_iommu.c.
+ *
+ * So, the only machvec that really supports loading the kdump kernel
+ * over 4 GB is "sn2".
+ */
+static int __init check_crashkernel_memory(unsigned long pbase, size_t size)
+{
+        if (ia64_platform_is("sn2") || ia64_platform_is("uv"))
+                return 1;
+        else
+                return pbase < (1UL << 32);
+}
+
 static void __init setup_crashkernel(unsigned long total, int *n)
 {
         unsigned long long base = 0, size = 0;
@@ -252,6 +271,16 @@ static void __init setup_crashkernel(unsigned long total, int *n)
                         base = kdump_find_rsvd_region(size,
                                         rsvd_region, *n);
                 }
+
+                if (!check_crashkernel_memory(base, size)) {
+                        pr_warning("crashkernel: There would be kdump memory "
+                                "at %ld GB but this is unusable because it "
+                                "must\nbe below 4 GB. Change the memory "
+                                "configuration of the machine.\n",
+                                (unsigned long)(base >> 30));
+                        return;
+                }
+
                 if (base != ~0UL) {
                         printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
                                         "for crashkernel (System RAM: %ldMB)\n",