AArch64: gdbserver: read pauth registers

[deliverable/binutils-gdb.git] / gdb / gdbserver / linux-aarch64-low.c

diff --git a/gdb/gdbserver/linux-aarch64-low.c b/gdb/gdbserver/linux-aarch64-low.c
index 1d34e319dfd5f677f7587d84ed868e95c023417e..20c75493b07c03c044258055219326c05e606128 100644 (file)
--- a/gdb/gdbserver/linux-aarch64-low.c
+++ b/gdb/gdbserver/linux-aarch64-low.c
@@ -1,7 +1,7 @@
 /* GNU/Linux/AArch64 specific low level interface, for the remote server for
    GDB.
 
-   Copyright (C) 2009-2018 Free Software Foundation, Inc.
+   Copyright (C) 2009-2019 Free Software Foundation, Inc.
    Contributed by ARM Ltd.
 
    This file is part of GDB.
@@ -84,22 +84,6 @@ is_sve_tdesc (void)
   return regcache->tdesc->reg_defs.size () == AARCH64_SVE_NUM_REGS;
 }
 
-/* Implementation of linux_target_ops method "cannot_store_register".  */
-
-static int
-aarch64_cannot_store_register (int regno)
-{
-  return regno >= AARCH64_NUM_REGS;
-}
-
-/* Implementation of linux_target_ops method "cannot_fetch_register".  */
-
-static int
-aarch64_cannot_fetch_register (int regno)
-{
-  return regno >= AARCH64_NUM_REGS;
-}
-
 static void
 aarch64_fill_gregset (struct regcache *regcache, void *buf)
 {
@@ -151,6 +135,23 @@ aarch64_store_fpregset (struct regcache *regcache, const void *buf)
   supply_register (regcache, AARCH64_FPCR_REGNUM, &regset->fpcr);
 }
 
+/* Store the pauth registers to regcache.  */
+
+static void
+aarch64_store_pauthregset (struct regcache *regcache, const void *buf)
+{
+  uint64_t *pauth_regset = (uint64_t *) buf;
+  int pauth_base = find_regno (regcache->tdesc, "pauth_dmask");
+
+  if (pauth_base == 0)
+    return;
+
+  supply_register (regcache, AARCH64_PAUTH_DMASK_REGNUM (pauth_base),
+                  &pauth_regset[0]);
+  supply_register (regcache, AARCH64_PAUTH_CMASK_REGNUM (pauth_base),
+                  &pauth_regset[1]);
+}
+
 /* Enable miscellaneous debugging output.  The name is historical - it
    was originally used to debug LinuxThreads support.  */
 extern int debug_threads;
@@ -501,6 +502,33 @@ aarch64_linux_new_fork (struct process_info *parent,
   *child->priv->arch_private = *parent->priv->arch_private;
 }
 
+/* Matches HWCAP_PACA in kernel header arch/arm64/include/uapi/asm/hwcap.h.  */
+#define AARCH64_HWCAP_PACA (1 << 30)
+
+/* Fetch the AT_HWCAP entry from the auxv vector.  */
+
+static bool
+aarch64_get_hwcap (unsigned long *valp)
+{
+  unsigned char *data = (unsigned char *) alloca (16);
+  int offset = 0;
+
+  while ((*the_target->read_auxv) (offset, data, 16) == 16)
+    {
+      unsigned long *data_p = (unsigned long *)data;
+      if (data_p[0] == AT_HWCAP)
+       {
+         *valp = data_p[1];
+         return true;
+       }
+
+      offset += 16;
+    }
+
+  *valp = 0;
+  return false;
+}
+
 /* Implementation of linux_target_ops method "arch_setup".  */
 
 static void
@@ -517,7 +545,10 @@ aarch64_arch_setup (void)
   if (is_elf64)
     {
       uint64_t vq = aarch64_sve_get_vq (tid);
-      current_process ()->tdesc = aarch64_linux_read_description (vq);
+      unsigned long hwcap = 0;
+      bool pauth_p = aarch64_get_hwcap (&hwcap) && (hwcap & AARCH64_HWCAP_PACA);
+
+      current_process ()->tdesc = aarch64_linux_read_description (vq, pauth_p);
     }
   else
     current_process ()->tdesc = tdesc_arm_with_neon;
@@ -550,6 +581,9 @@ static struct regset_info aarch64_regsets[] =
     sizeof (struct user_fpsimd_state), FP_REGS,
     aarch64_fill_fpregset, aarch64_store_fpregset
   },
+  { PTRACE_GETREGSET, PTRACE_SETREGSET, NT_ARM_PAC_MASK,
+    AARCH64_PAUTH_REGS_SIZE, OPTIONAL_REGS,
+    NULL, aarch64_store_pauthregset },
   NULL_REGSET
 };
 
@@ -576,6 +610,9 @@ static struct regset_info aarch64_sve_regsets[] =
     SVE_PT_SIZE (AARCH64_MAX_SVE_VQ, SVE_PT_REGS_SVE), EXTENDED_REGS,
     aarch64_sve_regs_copy_from_regcache, aarch64_sve_regs_copy_to_regcache
   },
+  { PTRACE_GETREGSET, PTRACE_SETREGSET, NT_ARM_PAC_MASK,
+    AARCH64_PAUTH_REGS_SIZE, OPTIONAL_REGS,
+    NULL, aarch64_store_pauthregset },
   NULL_REGSET
 };
 
@@ -3041,8 +3078,8 @@ struct linux_target_ops the_low_target =
 {
   aarch64_arch_setup,
   aarch64_regs_info,
-  aarch64_cannot_fetch_register,
-  aarch64_cannot_store_register,
+  NULL, /* cannot_fetch_register */
+  NULL, /* cannot_store_register */
   NULL, /* fetch_register */
   aarch64_get_pc,
   aarch64_set_pc,