xtensa: make DoubleExceptionVector literals fit the gap

Manually load references to exc_table from the explicit literal in order
to fit DoubleExceptionVector.literals into the available 16-byte gap
before DoubleExceptionVector.text in the absence of link time
relaxation. Without this fix DoubleExceptionVector.literal section
overlaps DoubleExceptionVector.text section in the linked vmlinux image.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>

diff --git a/arch/xtensa/kernel/vectors.S b/arch/xtensa/kernel/vectors.S
index 4462c1e..3a57c15 100644 (file)
--- a/arch/xtensa/kernel/vectors.S
+++ b/arch/xtensa/kernel/vectors.S
@@ -225,7 +225,13 @@ ENTRY(_DoubleExceptionVector)
        /* Window overflow/underflow exception. Get stack pointer. */
 
        mov     a3, a2
-       movi    a2, exc_table
+       /* This explicit literal and the following references to it are made
+        * in order to fit DoubleExceptionVector.literals into the available
+        * 16-byte gap before DoubleExceptionVector.text in the absence of
+        * link time relaxation. See kernel/vmlinux.lds.S
+        */
+       .literal .Lexc_table, exc_table
+       l32r    a2, .Lexc_table
        l32i    a2, a2, EXC_TABLE_KSTK
 
        /* Check for overflow/underflow exception, jump if overflow. */
@@ -255,7 +261,7 @@ ENTRY(_DoubleExceptionVector)
        s32i    a0, a2, PT_AREG0
 
        wsr     a3, excsave1            # save a3
-       movi    a3, exc_table
+       l32r    a3, .Lexc_table
 
        rsr     a0, exccause
        s32i    a0, a2, PT_DEPC         # mark it as a regular exception
@@ -267,7 +273,7 @@ ENTRY(_DoubleExceptionVector)
 
        /* a0: depc, a1: a1, a2: a2, a3: trashed, depc: a0, excsave1: a3 */
 
-       movi    a3, exc_table
+       l32r    a3, .Lexc_table
        s32i    a2, a3, EXC_TABLE_DOUBLE_SAVE   # temporary variable
 
        /* Enter critical section. */
@@ -296,7 +302,7 @@ ENTRY(_DoubleExceptionVector)
 
        /* a0: avail, a1: a1, a2: kstk, a3: avail, depc: a2, excsave: a3 */
 
-       movi    a3, exc_table
+       l32r    a3, .Lexc_table
        rsr     a0, exccause
        addx4   a0, a0, a3
        l32i    a0, a0, EXC_TABLE_FAST_USER