Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc

Pull powerpc LE updates from Ben Herrenschmidt:
 "With my previous pull request I mentioned some remaining Little Endian
  patches, notably support for our new ABI, which I was sitting on
  making sure it was all finalized.

  The toolchain folks confirmed it now, the new ABI is stable and merged
  with gcc, so we are all good.  Oh and we actually missed the actual
  Kconfig switch for LE so here it is, along with a couple more bug
  fixes.

  I have more fixes but not related to LE so I'll send them as a
  separate pull request tomorrow, let's get this one out of the way.

  Note that this supports running user space binaries using the new ABI,
  but the kernel itself still needs to be built with the old one.  We'll
  bring fixes for that after -rc1.

  Here's Anton log that goes with this series:

     This patch series adds support for the new ABI, LPAR support for
     H_SET_MODE and finally adds a kconfig option and defconfig.

     ABIv2 support was recently committed to binutils and gcc, and should
     be merged into glibc soon.  There are a number of very nice
     improvements including the removal of function descriptors.  Rusty's
     kernel patches allow binaries of either ABI to work, easing the
     transition"

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
  powerpc: Wrong DWARF CFI in the kernel vdso for little-endian / ELFv2
  powerpc: Add pseries_le_defconfig
  powerpc: Add CONFIG_CPU_LITTLE_ENDIAN kernel config option.
  powerpc: Don't use ELFv2 ABI to build the kernel
  powerpc: ELF2 binaries signal handling
  powerpc: ELF2 binaries launched directly.
  powerpc: Set eflags correctly for ELF ABIv2 core dumps.
  powerpc: Add TIF_ELF2ABI flag.
  pseries: Add H_SET_MODE to change exception endianness
  powerpc/pseries: Fix endian issues in pseries EEH code

3 files changed, 66 insertions, 25 deletions

diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 75c2d1009985..0650e18169f8 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -1086,25 +1086,45 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp)
         regs->msr = MSR_USER;
 #else
         if (!is_32bit_task()) {
-                unsigned long entry, toc;
+                unsigned long entry;
 
-                /* start is a relocated pointer to the function descriptor for
-                 * the elf _start routine.  The first entry in the function
-                 * descriptor is the entry address of _start and the second
-                 * entry is the TOC value we need to use.
-                 */
-                __get_user(entry, (unsigned long __user *)start);
-                __get_user(toc, (unsigned long __user *)start+1);
+                if (is_elf2_task()) {
+                        /* Look ma, no function descriptors! */
+                        entry = start;
 
-                /* Check whether the e_entry function descriptor entries
-                 * need to be relocated before we can use them.
-                 */
-                if (load_addr != 0) {
-                        entry += load_addr;
-                        toc   += load_addr;
+                        /*
+                         * Ulrich says:
+                         *   The latest iteration of the ABI requires that when
+                         *   calling a function (at its global entry point),
+                         *   the caller must ensure r12 holds the entry point
+                         *   address (so that the function can quickly
+                         *   establish addressability).
+                         */
+                        regs->gpr[12] = start;
+                        /* Make sure that's restored on entry to userspace. */
+                        set_thread_flag(TIF_RESTOREALL);
+                } else {
+                        unsigned long toc;
+
+                        /* start is a relocated pointer to the function
+                         * descriptor for the elf _start routine.  The first
+                         * entry in the function descriptor is the entry
+                         * address of _start and the second entry is the TOC
+                         * value we need to use.
+                         */
+                        __get_user(entry, (unsigned long __user *)start);
+                        __get_user(toc, (unsigned long __user *)start+1);
+
+                        /* Check whether the e_entry function descriptor entries
+                         * need to be relocated before we can use them.
+                         */
+                        if (load_addr != 0) {
+                                entry += load_addr;
+                                toc   += load_addr;
+                        }
+                        regs->gpr[2] = toc;
                 }
                 regs->nip = entry;
-                regs->gpr[2] = toc;
                 regs->msr = MSR_USER64;
         } else {
                 regs->nip = start;
diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index b3c615764c9b..e66f67b8b9e6 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -701,12 +701,6 @@ badframe:
 int handle_rt_signal64(int signr, struct k_sigaction *ka, siginfo_t *info,
                 sigset_t *set, struct pt_regs *regs)
 {
-        /* Handler is *really* a pointer to the function descriptor for
-         * the signal routine.  The first entry in the function
-         * descriptor is the entry address of signal and the second
-         * entry is the TOC value we need to use.
-         */
-        func_descr_t __user *funct_desc_ptr;
         struct rt_sigframe __user *frame;
         unsigned long newsp = 0;
         long err = 0;
@@ -766,19 +760,32 @@ int handle_rt_signal64(int signr, struct k_sigaction *ka, siginfo_t *info,
                         goto badframe;
                 regs->link = (unsigned long) &frame->tramp[0];
         }
-        funct_desc_ptr = (func_descr_t __user *) ka->sa.sa_handler;
 
         /* Allocate a dummy caller frame for the signal handler. */
         newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
         err |= put_user(regs->gpr[1], (unsigned long __user *)newsp);
 
         /* Set up "regs" so we "return" to the signal handler. */
-        err |= get_user(regs->nip, &funct_desc_ptr->entry);
+        if (is_elf2_task()) {
+                regs->nip = (unsigned long) ka->sa.sa_handler;
+                regs->gpr[12] = regs->nip;
+        } else {
+                /* Handler is *really* a pointer to the function descriptor for
+                 * the signal routine.  The first entry in the function
+                 * descriptor is the entry address of signal and the second
+                 * entry is the TOC value we need to use.
+                 */
+                func_descr_t __user *funct_desc_ptr =
+                        (func_descr_t __user *) ka->sa.sa_handler;
+
+                err |= get_user(regs->nip, &funct_desc_ptr->entry);
+                err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
+        }
+
         /* enter the signal handler in native-endian mode */
         regs->msr &= ~MSR_LE;
         regs->msr |= (MSR_KERNEL & MSR_LE);
         regs->gpr[1] = newsp;
-        err |= get_user(regs->gpr[2], &funct_desc_ptr->toc);
         regs->gpr[3] = signr;
         regs->result = 0;
         if (ka->sa.sa_flags & SA_SIGINFO) {
diff --git a/arch/powerpc/kernel/vdso64/sigtramp.S b/arch/powerpc/kernel/vdso64/sigtramp.S
index 45ea281e9a21..542c6f422e4d 100644
--- a/arch/powerpc/kernel/vdso64/sigtramp.S
+++ b/arch/powerpc/kernel/vdso64/sigtramp.S
@@ -142,6 +142,13 @@ V_FUNCTION_END(__kernel_sigtramp_rt64)
 /* Size of CR reg in DWARF unwind info. */
 #define CRSIZE  4
 
+/* Offset of CR reg within a full word. */
+#ifdef __LITTLE_ENDIAN__
+#define CROFF 0
+#else
+#define CROFF (RSIZE - CRSIZE)
+#endif
+
 /* This is the offset of the VMX reg pointer.  */
 #define VREGS   48*RSIZE+33*8
 
@@ -181,7 +188,14 @@ V_FUNCTION_END(__kernel_sigtramp_rt64)
   rsave (31, 31*RSIZE);                                                 \
   rsave (67, 32*RSIZE);         /* ap, used as temp for nip */          \
   rsave (65, 36*RSIZE);         /* lr */                                \
-  rsave (70, 38*RSIZE + (RSIZE - CRSIZE)) /* cr */
+  rsave (68, 38*RSIZE + CROFF); /* cr fields */                         \
+  rsave (69, 38*RSIZE + CROFF);                                         \
+  rsave (70, 38*RSIZE + CROFF);                                         \
+  rsave (71, 38*RSIZE + CROFF);                                         \
+  rsave (72, 38*RSIZE + CROFF);                                         \
+  rsave (73, 38*RSIZE + CROFF);                                         \
+  rsave (74, 38*RSIZE + CROFF);                                         \
+  rsave (75, 38*RSIZE + CROFF)
 
 /* Describe where the FP regs are saved.  */
 #define EH_FRAME_FP \