Commit 0c8c0f03e3a2 ("x86/fpu, sched: Dynamically allocate 'struct fpu'")
moved the thread_struct to the bottom of task_struct. As a result, the
offset is now too large to be used in an immediate stfpc operation on s390,
resulting in the following compile error.

arch/s390/kernel/traps.c: Assembler messages:
arch/s390/kernel/traps.c:262: Error: operand out of range
        (0x00000000000023e8 is not between 0x0000000000000000 and 
0x0000000000000fff)
arch/s390/kernel/traps.c:300: Error: operand out of range
        (0x00000000000023e8 is not between 0x0000000000000000 and 
0x0000000000000fff)

Use a local variable to store fpc to solve the problem.

Cc: Ingo Molnar <[email protected]>
Signed-off-by: Guenter Roeck <[email protected]>
---
Compile tested only.
Wonder if storing fpc in current->thread.fp_regs.fpc is necessary.

 arch/s390/kernel/traps.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/arch/s390/kernel/traps.c b/arch/s390/kernel/traps.c
index 4d96c9f53455..73bd46db1298 100644
--- a/arch/s390/kernel/traps.c
+++ b/arch/s390/kernel/traps.c
@@ -252,6 +252,7 @@ int alloc_vector_registers(struct task_struct *tsk)
 void vector_exception(struct pt_regs *regs)
 {
        int si_code, vic;
+       __u32 fpc;
 
        if (!MACHINE_HAS_VX) {
                do_trap(regs, SIGILL, ILL_ILLOPN, "illegal operation");
@@ -259,8 +260,10 @@ void vector_exception(struct pt_regs *regs)
        }
 
        /* get vector interrupt code from fpc */
-       asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
-       vic = (current->thread.fp_regs.fpc & 0xf00) >> 8;
+       asm volatile("stfpc %0" : "=m" (fpc));
+       current->thread.fp_regs.fpc = fpc;
+       vic = (fpc & 0xf00) >> 8;
+
        switch (vic) {
        case 1: /* invalid vector operation */
                si_code = FPE_FLTINV;
@@ -294,25 +297,27 @@ void data_exception(struct pt_regs *regs)
 {
        __u16 __user *location;
        int signal = 0;
+       __u32 fpc;
 
        location = get_trap_ip(regs);
 
-       asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
+       asm volatile("stfpc %0" : "=m" (fpc));
+       current->thread.fp_regs.fpc = fpc;
        /* Check for vector register enablement */
        if (MACHINE_HAS_VX && !current->thread.vxrs &&
-           (current->thread.fp_regs.fpc & FPC_DXC_MASK) == 0xfe00) {
+           (fpc & FPC_DXC_MASK) == 0xfe00) {
                alloc_vector_registers(current);
                /* Vector data exception is suppressing, rewind psw. */
                regs->psw.addr = __rewind_psw(regs->psw, regs->int_code >> 16);
                clear_pt_regs_flag(regs, PIF_PER_TRAP);
                return;
        }
-       if (current->thread.fp_regs.fpc & FPC_DXC_MASK)
+       if (fpc & FPC_DXC_MASK)
                signal = SIGFPE;
        else
                signal = SIGILL;
        if (signal == SIGFPE)
-               do_fp_trap(regs, current->thread.fp_regs.fpc);
+               do_fp_trap(regs, fpc);
        else if (signal)
                do_trap(regs, signal, ILL_ILLOPN, "data exception");
 }
-- 
2.1.0

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