Re: [Qemu-ppc] [PATCH 1/3] linux-user: Handle ELFv2 PPC64 binaries in user mode.

[關振德]

Hi

On Thu, May 8, 2014 at 1:36 AM, Alexander Graf <address@hidden> wrote:          3

Please write bitmasks in hex.

Will fix.

 

+
  /* PowerPC relocations defined by the ABIs */
  #define R_PPC_NONE            0
  #define R_PPC_ADDR32          1       /* 32bit absolute address */
diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 995f999..b96d64a 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -777,12 +777,18 @@ static uint32_t get_elf_hwcap(void)
          NEW_AUX_ENT(AT_IGNOREPPC, AT_IGNOREPPC);        \
      } while (0)
  +static inline uint32_t get_ppc64_abi(struct image_info *infop);
+
  static inline void init_thread(struct target_pt_regs *_regs, struct image_info *infop)
  {
      _regs->gpr[1] = infop->start_stack;
  #if defined(TARGET_PPC64) && !defined(TARGET_ABI32)
-    _regs->gpr[2] = ldq_raw(infop->entry + 8) + infop->load_bias;
-    infop->entry = ldq_raw(infop->entry) + infop->load_bias;
+    if (get_ppc64_abi(infop) < 2) {
+      _regs->gpr[2] = ldq_raw(infop->entry + 8) + infop->load_bias;
+      infop->entry = ldq_raw(infop->entry) + infop->load_bias;
+    } else {
+      _regs->gpr[12] = infop->entry;  /* r12 set to global entry address */

Uli, is this correct? Also, why don't w need to adjust for the load_bias with ELFv2 anymore?

No.  This is a bug.  It was not caught by testing because load_bias is 0 I guess.

 

+    }
  #endif
      _regs->nip = infop->entry;
  }
@@ -1152,6 +1158,13 @@ static inline void init_thread(struct target_pt_regs *regs, struct image_info *i
    #include "elf.h"
  +#ifdef TARGET_PPC
+static inline uint32_t get_ppc64_abi(struct image_info *infop)
+{
+  return infop->elf_flags & EF_PPC64_ABI;
+}
+#endif

I'm not sure this is more readable than doing it inline ... :).

This is done so because the elf header is not yet included before the callee.  To eliminate this I need to move the include before ppc's init_thread.  Is that okay?

 

Thanks for the comments.

-Doug