sparc64: Don't clibber fixed registers in __multi4.

%g4 and %g5 are fixed registers used by the kernel for the thread
pointer and the per-cpu offset.  Use %o4 and %g7 instead.

Diagnosis by Anthony Yznaga.

Fixes: 1b4af13ff2cc ("sparc64: Add __multi3 for gcc 7.x and later.")
Reported-by: Anatoly Pugachev <matorola@gmail.com>
Tested-by: Anatoly Pugachev <matorola@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/arch/sparc/lib/multi3.S b/arch/sparc/lib/multi3.S
index d6b6c97fe3c73061f911737a5da23ab41a3eab77..703127aaf4a5015ee4a1099e6129735f7162222b 100644 (file)
--- a/arch/sparc/lib/multi3.S
+++ b/arch/sparc/lib/multi3.S
@@ -5,26 +5,26 @@
        .align  4
 ENTRY(__multi3) /* %o0 = u, %o1 = v */
        mov     %o1, %g1
-       srl     %o3, 0, %g4
-       mulx    %g4, %g1, %o1
+       srl     %o3, 0, %o4
+       mulx    %o4, %g1, %o1
        srlx    %g1, 0x20, %g3
-       mulx    %g3, %g4, %g5
-       sllx    %g5, 0x20, %o5
-       srl     %g1, 0, %g4
+       mulx    %g3, %o4, %g7
+       sllx    %g7, 0x20, %o5
+       srl     %g1, 0, %o4
        sub     %o1, %o5, %o5
        srlx    %o5, 0x20, %o5
-       addcc   %g5, %o5, %g5
+       addcc   %g7, %o5, %g7
        srlx    %o3, 0x20, %o5
-       mulx    %g4, %o5, %g4
+       mulx    %o4, %o5, %o4
        mulx    %g3, %o5, %o5
        sethi   %hi(0x80000000), %g3
-       addcc   %g5, %g4, %g5
-       srlx    %g5, 0x20, %g5
+       addcc   %g7, %o4, %g7
+       srlx    %g7, 0x20, %g7
        add     %g3, %g3, %g3
        movcc   %xcc, %g0, %g3
-       addcc   %o5, %g5, %o5
-       sllx    %g4, 0x20, %g4
-       add     %o1, %g4, %o1
+       addcc   %o5, %g7, %o5
+       sllx    %o4, 0x20, %o4
+       add     %o1, %o4, %o1
        add     %o5, %g3, %g2
        mulx    %g1, %o2, %g1
        add     %g1, %g2, %g1