Merge tag 'linus-mce-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras

[firefly-linux-kernel-4.4.55.git] / arch / tile / kernel / intvec_64.S

diff --git a/arch/tile/kernel/intvec_64.S b/arch/tile/kernel/intvec_64.S
index 79c93e10ba27b1a11c939e216233ec5956b6b11a..30ae76e50c44e458fc5b87e2d8712de3219383a5 100644 (file)
--- a/arch/tile/kernel/intvec_64.S
+++ b/arch/tile/kernel/intvec_64.S
@@ -22,6 +22,7 @@
 #include <asm/irqflags.h>
 #include <asm/asm-offsets.h>
 #include <asm/types.h>
+#include <asm/signal.h>
 #include <hv/hypervisor.h>
 #include <arch/abi.h>
 #include <arch/interrupts.h>
@@ -605,6 +606,10 @@ handle_interrupt:
  * This routine takes a boolean in r30 indicating if this is an NMI.
  * If so, we also expect a boolean in r31 indicating whether to
  * re-enable the oprofile interrupts.
+ *
+ * Note that .Lresume_userspace is jumped to directly in several
+ * places, and we need to make sure r30 is set correctly in those
+ * callers as well.
  */
 STD_ENTRY(interrupt_return)
        /* If we're resuming to kernel space, don't check thread flags. */
@@ -641,6 +646,20 @@ STD_ENTRY(interrupt_return)
 .Lresume_userspace:
        FEEDBACK_REENTER(interrupt_return)
 
+       /*
+        * Use r33 to hold whether we have already loaded the callee-saves
+        * into ptregs.  We don't want to do it twice in this loop, since
+        * then we'd clobber whatever changes are made by ptrace, etc.
+        */
+       {
+        movei  r33, 0
+        move   r32, sp
+       }
+
+       /* Get base of stack in r32. */
+       EXTRACT_THREAD_INFO(r32)
+
+.Lretry_work_pending:
        /*
         * Disable interrupts so as to make sure we don't
         * miss an interrupt that sets any of the thread flags (like
@@ -651,9 +670,6 @@ STD_ENTRY(interrupt_return)
        IRQ_DISABLE(r20, r21)
        TRACE_IRQS_OFF  /* Note: clobbers registers r0-r29 */
 
-       /* Get base of stack in r32; note r30/31 are used as arguments here. */
-       GET_THREAD_INFO(r32)
-
 
        /* Check to see if there is any work to do before returning to user. */
        {
@@ -669,16 +685,18 @@ STD_ENTRY(interrupt_return)
 
        /*
         * Make sure we have all the registers saved for signal
-        * handling or single-step.  Call out to C code to figure out
+        * handling or notify-resume.  Call out to C code to figure out
         * exactly what we need to do for each flag bit, then if
         * necessary, reload the flags and recheck.
         */
-       push_extra_callee_saves r0
        {
         PTREGS_PTR(r0, PTREGS_OFFSET_BASE)
-        jal    do_work_pending
+        bnez   r33, 1f
        }
-       bnez    r0, .Lresume_userspace
+       push_extra_callee_saves r0
+       movei   r33, 1
+1:     jal     do_work_pending
+       bnez    r0, .Lretry_work_pending
 
        /*
         * In the NMI case we
@@ -963,11 +981,16 @@ handle_syscall:
        shl16insli r20, r20, hw0(irq_stat + IRQ_CPUSTAT_SYSCALL_COUNT_OFFSET)
        add     r20, r20, tp
        ld4s    r21, r20
-       addi    r21, r21, 1
-       st4     r20, r21
+       {
+        addi   r21, r21, 1
+        move   r31, sp
+       }
+       {
+        st4    r20, r21
+        EXTRACT_THREAD_INFO(r31)
+       }
 
        /* Trace syscalls, if requested. */
-       GET_THREAD_INFO(r31)
        addi    r31, r31, THREAD_INFO_FLAGS_OFFSET
        ld      r30, r31
        andi    r30, r30, _TIF_SYSCALL_TRACE
@@ -1039,11 +1062,28 @@ handle_syscall:
 
        /* Do syscall trace again, if requested. */
        ld      r30, r31
-       andi    r30, r30, _TIF_SYSCALL_TRACE
-       beqzt   r30, 1f
+       andi    r0, r30, _TIF_SYSCALL_TRACE
+       {
+        andi    r0, r30, _TIF_SINGLESTEP
+        beqzt   r0, 1f
+       }
        jal     do_syscall_trace
        FEEDBACK_REENTER(handle_syscall)
-1:     j       .Lresume_userspace   /* jump into middle of interrupt_return */
+       andi    r0, r30, _TIF_SINGLESTEP
+
+1:     beqzt   r0, 2f
+
+       /* Single stepping -- notify ptrace. */
+       {
+        movei   r0, SIGTRAP
+        jal     ptrace_notify
+       }
+       FEEDBACK_REENTER(handle_syscall)
+
+2:     {
+        movei  r30, 0               /* not an NMI */
+        j      .Lresume_userspace   /* jump into middle of interrupt_return */
+       }
 
 .Lcompat_syscall:
        /*
@@ -1077,7 +1117,10 @@ handle_syscall:
         movei  r28, -ENOSYS
        }
        st      r29, r28
-       j       .Lresume_userspace   /* jump into middle of interrupt_return */
+       {
+        movei  r30, 0               /* not an NMI */
+        j      .Lresume_userspace   /* jump into middle of interrupt_return */
+       }
        STD_ENDPROC(handle_syscall)
 
        /* Return the address for oprofile to suppress in backtraces. */
@@ -1093,7 +1136,10 @@ STD_ENTRY(ret_from_fork)
        jal     sim_notify_fork
        jal     schedule_tail
        FEEDBACK_REENTER(ret_from_fork)
-       j       .Lresume_userspace
+       {
+        movei  r30, 0               /* not an NMI */
+        j      .Lresume_userspace   /* jump into middle of interrupt_return */
+       }
        STD_ENDPROC(ret_from_fork)
 
 /* Various stub interrupt handlers and syscall handlers */
@@ -1156,6 +1202,18 @@ int_unalign:
        push_extra_callee_saves r0
        j       do_trap
 
+/* Fill the return address stack with nonzero entries. */
+STD_ENTRY(fill_ra_stack)
+       {
+        move   r0, lr
+        jal    1f
+       }
+1:     jal     2f
+2:     jal     3f
+3:     jal     4f
+4:     jrp     r0
+       STD_ENDPROC(fill_ra_stack)
+
 /* Include .intrpt1 array of interrupt vectors */
        .section ".intrpt1", "ax"
 
@@ -1166,7 +1224,7 @@ int_unalign:
 #define do_hardwall_trap bad_intr
 #endif
 
-       int_hand     INT_MEM_ERROR, MEM_ERROR, bad_intr
+       int_hand     INT_MEM_ERROR, MEM_ERROR, do_trap
        int_hand     INT_SINGLE_STEP_3, SINGLE_STEP_3, bad_intr
 #if CONFIG_KERNEL_PL == 2
        int_hand     INT_SINGLE_STEP_2, SINGLE_STEP_2, gx_singlestep_handle